Better coffee, easier parking and more: the fascinating physics of daily life
It is book week here at Physics World and over the course of three days we are presenting conversations with the authors of three fascinating and fun books about physics. First up is my Physics World colleague Michael Banks, whose book Physics Around the Clock: Adventures in the Science of Everyday Living starts with your morning coffee and ends with a formula for making your evening television viewing more satisfying.
As well as the rich physics of coffee, we chat about strategies for finding the best parking spot and the efficient boarding of aeroplanes. If you have ever wondered why a runner’s ponytail swings from side-to-side when they reach a certain speed – we have the answer for you.
Other daily mysteries that we explore include how a hard steel razor blade can be dulled by cutting relatively soft hairs and why quasiparticles called “jamitons” are helping physicists understand the spontaneous appearance of traffic jams. And a warning for squeamish listeners, we do talk about the amazing virus-spreading capabilities of a flushing toilet.
This episode is supported by the APS Global Physics Summit, which takes place on 15–20 March, 2026, in Denver, Colorado, and online.
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1 00:00:07,919 --> 00:00:10,719 Hello, and welcome to the Physics World weekly 2 00:00:10,719 --> 00:00:12,660 podcast. I'm Hamish Johnston. 3 00:00:13,205 --> 00:00:15,925 It's book week here at Physics World. And 4 00:00:15,925 --> 00:00:18,505 over the course of three days, we're presenting 5 00:00:18,804 --> 00:00:20,425 conversations with the authors 6 00:00:20,725 --> 00:00:24,664 of three fascinating and fun books about physics. 7 00:00:25,379 --> 00:00:28,339 First up is my Physics World colleague, Michael 8 00:00:28,339 --> 00:00:31,800 Banks, whose book Physics Around the Clock, 9 00:00:32,179 --> 00:00:35,320 Adventures in the Science of Everyday Living, 10 00:00:35,859 --> 00:00:38,895 starts with your morning coffee and ends with 11 00:00:38,895 --> 00:00:42,755 a formula for making your evening television viewing 12 00:00:43,135 --> 00:00:44,115 more satisfying. 13 00:00:45,375 --> 00:00:47,875 This episode is supported by the APS 14 00:00:48,495 --> 00:00:49,979 Global Physics Summit, 15 00:00:50,460 --> 00:00:54,189 which takes place on March 16 00:00:54,189 --> 00:00:56,320 2026 17 00:00:56,539 --> 00:00:58,000 in Denver, Colorado 18 00:00:58,700 --> 00:00:59,840 and online. 19 00:01:00,780 --> 00:01:03,759 At the largest physics meeting in the world, 20 00:01:04,155 --> 00:01:06,334 you can join thousands of physicists, 21 00:01:06,875 --> 00:01:10,234 students, and policy leaders for a week of 22 00:01:10,234 --> 00:01:11,614 connection and collaboration. 23 00:01:12,954 --> 00:01:16,314 Immerse yourself in the cutting edge science that's 24 00:01:16,314 --> 00:01:18,255 shaping our shared future, 25 00:01:18,609 --> 00:01:21,090 and be a part of the global physics 26 00:01:21,090 --> 00:01:21,590 community 27 00:01:22,369 --> 00:01:23,590 driving innovation 28 00:01:23,890 --> 00:01:24,390 forward. 29 00:01:25,170 --> 00:01:29,829 Explore the meeting at summit.aps.org. 30 00:01:31,114 --> 00:01:34,234 Why do Cheerios tend to stick together when 31 00:01:34,234 --> 00:01:36,174 floating in a bowl of milk? 32 00:01:36,715 --> 00:01:39,594 Why does a runner's ponytail swing back and 33 00:01:39,594 --> 00:01:40,094 forth 34 00:01:40,395 --> 00:01:41,935 rather than up and down? 35 00:01:42,474 --> 00:01:44,974 These might not be the most pressing questions 36 00:01:45,034 --> 00:01:45,775 in physics, 37 00:01:46,200 --> 00:01:48,700 but getting to the answers is both fun 38 00:01:48,920 --> 00:01:50,379 and provides insights 39 00:01:50,680 --> 00:01:51,579 into important 40 00:01:52,040 --> 00:01:53,260 scientific concepts. 41 00:01:54,119 --> 00:01:55,739 These are just two examples 42 00:01:56,200 --> 00:01:59,659 of everyday physics that Michael Banks explores 43 00:01:59,959 --> 00:02:01,259 in his new book, 44 00:02:01,604 --> 00:02:04,084 And he joins me here in the Physics 45 00:02:04,084 --> 00:02:04,984 World studio. 46 00:02:05,604 --> 00:02:06,344 Hi, Michael. 47 00:02:06,724 --> 00:02:08,025 Welcome to the podcast. 48 00:02:08,805 --> 00:02:09,544 Hi, Hamish. 49 00:02:09,925 --> 00:02:12,724 So, Michael, before we explore your book, and 50 00:02:12,724 --> 00:02:14,504 some of the amazing anecdotes, 51 00:02:14,884 --> 00:02:17,500 physics anecdotes that you've got in there, I 52 00:02:17,500 --> 00:02:18,780 thought I'd ask you about, 53 00:02:19,900 --> 00:02:23,019 the the the book itself. What motivated you? 54 00:02:23,019 --> 00:02:25,439 What inspired you to write the book? 55 00:02:26,300 --> 00:02:27,900 Yeah. So the book is about the the 56 00:02:27,900 --> 00:02:29,979 physics of everyday life. So this is kind 57 00:02:29,979 --> 00:02:31,819 of physics you might come across in your 58 00:02:31,819 --> 00:02:33,875 daily routine, you know, starting off, you know, 59 00:02:33,875 --> 00:02:34,375 breakfast, 60 00:02:35,074 --> 00:02:36,215 all the way to bed. 61 00:02:36,754 --> 00:02:39,074 And I've always enjoyed writing about topics that 62 00:02:39,074 --> 00:02:41,555 you might call everyday science. You know, this 63 00:02:41,555 --> 00:02:44,115 is, research about topics that you kind of 64 00:02:44,115 --> 00:02:46,650 might come across, whether it's a Cheerios effect 65 00:02:46,650 --> 00:02:48,669 at breakfast or the dribbling teapot 66 00:02:49,209 --> 00:02:50,009 or things like that. 67 00:02:51,050 --> 00:02:52,810 And so those kind of topics have always 68 00:02:52,810 --> 00:02:54,889 kind of excited me and I've enjoyed writing 69 00:02:54,889 --> 00:02:57,465 about. And actually regular readers of Physics World, 70 00:02:58,425 --> 00:03:01,705 will may well recognize the regular column called 71 00:03:01,705 --> 00:03:03,864 Quanta, you know, which features these kind of, 72 00:03:04,344 --> 00:03:07,305 research stories, you know, about everyday life. Yeah. 73 00:03:07,305 --> 00:03:09,405 I thought some of them looked very familiar. 74 00:03:10,185 --> 00:03:11,004 That's right. Yeah. 75 00:03:11,680 --> 00:03:13,760 The actual the book itself is organized into 76 00:03:13,760 --> 00:03:14,580 12 chapters, 77 00:03:15,120 --> 00:03:16,560 and that takes you all the way from 78 00:03:16,560 --> 00:03:18,800 breakfast to breakfast itself when you look at 79 00:03:18,800 --> 00:03:20,319 things like, you know, how the physics of 80 00:03:20,400 --> 00:03:22,180 even the physics of eggs, cooking, 81 00:03:22,879 --> 00:03:24,879 as I mentioned, the Cheerios effect, the Brazil 82 00:03:24,879 --> 00:03:26,844 nut effect, Physics of Coffee as well. You 83 00:03:26,844 --> 00:03:30,205 know, coffee is a favourite of, physicists, definitely 84 00:03:30,205 --> 00:03:31,745 a physicist's favourite beverage. 85 00:03:32,444 --> 00:03:34,125 So it starts off with the morning routine 86 00:03:34,125 --> 00:03:35,645 looking at, you know, you take your dog 87 00:03:35,645 --> 00:03:36,625 out for a walk, 88 00:03:37,004 --> 00:03:38,444 when it gets wet and it carries out 89 00:03:38,444 --> 00:03:39,724 a wet dog shake, you know, how it 90 00:03:39,724 --> 00:03:41,759 manages to expel all that water 91 00:03:42,139 --> 00:03:44,159 and, you know, help itself dry off. 92 00:03:44,459 --> 00:03:46,780 Then it moves into the daytime, so certain 93 00:03:46,780 --> 00:03:48,780 kind of daytime activities you might carry out. 94 00:03:48,780 --> 00:03:50,780 So say, you know, physics of you might 95 00:03:50,780 --> 00:03:52,000 come across in the garden. 96 00:03:53,034 --> 00:03:55,114 If you're playing sports, for example, you know, 97 00:03:55,114 --> 00:03:57,775 things like the Magnus effect or spinning balls. 98 00:03:58,314 --> 00:04:00,074 And then it kind of finishes off then 99 00:04:00,074 --> 00:04:01,914 into the evening. So looking at some of 100 00:04:01,914 --> 00:04:04,254 the physics that you, come across, 101 00:04:04,794 --> 00:04:06,814 your favorite takeaways, like pizzas, 102 00:04:07,200 --> 00:04:09,700 physics of pasta. Pastas are definitely a big, 103 00:04:10,159 --> 00:04:12,260 another big area of research that physicists, 104 00:04:13,439 --> 00:04:15,920 work on. Physics of champagne, that might not 105 00:04:15,920 --> 00:04:17,680 be a daily occurrence of champagne, but, you 106 00:04:17,680 --> 00:04:20,480 know, the physics of, bubbles in certain beverages, 107 00:04:20,480 --> 00:04:22,319 there's a lot of interesting physics that goes 108 00:04:22,319 --> 00:04:22,935 on there. 109 00:04:23,574 --> 00:04:25,095 And then, yeah, so then it basically goes, 110 00:04:25,095 --> 00:04:26,694 you know, from breakfast to bed all the 111 00:04:26,694 --> 00:04:29,035 way across. And it was really, you know, 112 00:04:30,615 --> 00:04:32,855 interesting. And also, you know, writing the book, 113 00:04:32,855 --> 00:04:34,294 it was, a lot I had a lot 114 00:04:34,294 --> 00:04:35,574 of fun writing it because there's a lot 115 00:04:35,574 --> 00:04:38,189 of, like, fun anecdotes in there about researchers 116 00:04:38,189 --> 00:04:40,610 who come across all these different different ideas, 117 00:04:41,069 --> 00:04:42,290 in their daily research. 118 00:04:42,990 --> 00:04:44,670 Yeah. I mean, it really sort of, 119 00:04:46,430 --> 00:04:48,110 touched a note with me. I mean, right 120 00:04:48,110 --> 00:04:50,350 from the beginning because, you know, like a 121 00:04:50,350 --> 00:04:52,189 lot of people, I'm pretty useless in the 122 00:04:52,189 --> 00:04:52,689 morning, 123 00:04:53,384 --> 00:04:55,785 without my first cup of coffee. Well, actually, 124 00:04:55,785 --> 00:04:58,264 without my first two cups of coffee. You 125 00:04:58,264 --> 00:05:00,504 know, as you pointed out, coffee is is 126 00:05:00,504 --> 00:05:03,064 is a fascinating thing. You know, there's some 127 00:05:03,384 --> 00:05:05,245 it's it's a granular material, 128 00:05:05,779 --> 00:05:08,180 and you're you're sort of forcing hot water 129 00:05:08,180 --> 00:05:10,020 or steam through it. There's a lot of 130 00:05:10,020 --> 00:05:10,920 physics there. 131 00:05:11,540 --> 00:05:13,460 I've got a steam kettle at home, and 132 00:05:13,460 --> 00:05:14,900 I think you touch on, 133 00:05:15,699 --> 00:05:18,340 on the physics of of the whistles in 134 00:05:18,340 --> 00:05:20,545 a in a steam kettle, which I thought 135 00:05:20,545 --> 00:05:22,464 was very interesting. But so so of all 136 00:05:22,464 --> 00:05:24,064 the things that you've written about quite a 137 00:05:24,064 --> 00:05:26,225 few aspects of of the physics of coffee, 138 00:05:26,225 --> 00:05:27,665 what what do you think is the most 139 00:05:27,665 --> 00:05:28,165 interesting 140 00:05:28,705 --> 00:05:30,785 little tidbit that you've got in the book 141 00:05:30,785 --> 00:05:31,524 about coffee? 142 00:05:32,050 --> 00:05:33,970 One of the interesting aspects is actually when 143 00:05:33,970 --> 00:05:35,030 you grind coffee. 144 00:05:35,889 --> 00:05:37,670 Some some of us, if we have, 145 00:05:38,129 --> 00:05:39,910 you know, like a bean bean to 146 00:05:40,210 --> 00:05:42,370 cup type of machinery, you'll kind of put 147 00:05:42,370 --> 00:05:44,685 the beans in, they'll grind, and then the 148 00:05:44,685 --> 00:05:47,324 hot water presses through. I've got some people 149 00:05:47,324 --> 00:05:49,345 just like to grind beans anyway. 150 00:05:50,204 --> 00:05:52,044 But one interesting thing though is about, 151 00:05:52,524 --> 00:05:55,884 the static electricity that's produced during the grinding 152 00:05:55,884 --> 00:05:56,865 process itself. 153 00:05:57,949 --> 00:06:00,189 So, actually, some researchers studied this in in 154 00:06:00,189 --> 00:06:00,990 details. There's a, 155 00:06:02,110 --> 00:06:03,250 Christopher Hendon, 156 00:06:03,949 --> 00:06:06,269 a researcher, a geochemist in The US. He 157 00:06:06,269 --> 00:06:08,370 was doing demonstrations at his university. 158 00:06:09,149 --> 00:06:09,550 And, 159 00:06:10,944 --> 00:06:13,205 some volcanologists, so people who study volcanoes, 160 00:06:13,824 --> 00:06:16,225 were kind of intrigued by this demonstration of, 161 00:06:16,785 --> 00:06:18,485 coffee grinding that he was doing. 162 00:06:19,024 --> 00:06:20,705 And they kind of asked him, oh, yeah. 163 00:06:20,705 --> 00:06:21,985 What do you what do you think about, 164 00:06:21,985 --> 00:06:23,665 you know, teaming up to to look at 165 00:06:23,665 --> 00:06:26,100 what happens when you actually grind the coffee 166 00:06:26,100 --> 00:06:28,819 beans themselves, what's what the process that's, occurring 167 00:06:28,819 --> 00:06:31,240 there. So we teamed up with these, researchers 168 00:06:31,300 --> 00:06:33,099 and they they actually discovered that there's actually 169 00:06:33,099 --> 00:06:35,300 a lot of static electricity that was produced 170 00:06:35,300 --> 00:06:37,540 during the process itself. That's, like, kind of, 171 00:06:37,540 --> 00:06:38,120 the metal 172 00:06:38,985 --> 00:06:41,064 blade grinding up the beans at, you know, 173 00:06:41,064 --> 00:06:42,365 incredibly high speed. 174 00:06:42,745 --> 00:06:45,225 And what this actually happens then is basically 175 00:06:45,225 --> 00:06:45,964 the coffee 176 00:06:46,345 --> 00:06:47,485 actually clumps together. 177 00:06:48,105 --> 00:06:50,024 So you kind of, you get the, obviously, 178 00:06:50,024 --> 00:06:51,865 the very little kind of minuscule grains, but 179 00:06:51,865 --> 00:06:53,550 then you also get kind of bigger clumps 180 00:06:53,629 --> 00:06:55,409 due to this kind of static electricity. 181 00:06:56,669 --> 00:06:59,470 But the actual implication of that is that 182 00:06:59,470 --> 00:07:02,189 then the water doesn't pass fully through the 183 00:07:02,189 --> 00:07:04,449 grinds properly because of this clumping. 184 00:07:05,069 --> 00:07:05,970 And that actually 185 00:07:06,349 --> 00:07:07,409 results in a weaker 186 00:07:07,949 --> 00:07:08,449 brew. 187 00:07:09,064 --> 00:07:12,204 So basically, by this static electricity from happening, 188 00:07:12,344 --> 00:07:13,784 the water's kind of like looking for an 189 00:07:13,784 --> 00:07:15,865 easy escape route through the beans, which or 190 00:07:15,865 --> 00:07:17,164 through the through the grounds, 191 00:07:17,625 --> 00:07:20,185 which it then can manage to do if 192 00:07:20,185 --> 00:07:21,805 lots of it is clumped together. 193 00:07:22,769 --> 00:07:25,509 So one technique actually, which is happens in 194 00:07:25,810 --> 00:07:27,649 the coffee industry itself, is to add a 195 00:07:27,649 --> 00:07:30,050 little bit of just a little touch of 196 00:07:30,050 --> 00:07:30,550 water 197 00:07:31,490 --> 00:07:32,709 to the beans themselves. 198 00:07:33,649 --> 00:07:35,430 And when they're in then being ground, 199 00:07:35,884 --> 00:07:37,324 they don't clump so much. So then it 200 00:07:37,324 --> 00:07:39,245 kind of, like, can negate the statics in 201 00:07:39,245 --> 00:07:41,324 some way. So Hendon and colleagues, they then 202 00:07:41,324 --> 00:07:44,125 carried out experiments where they added some water 203 00:07:44,125 --> 00:07:45,884 to it and then to then measure the 204 00:07:45,884 --> 00:07:47,964 resulting static, and they found, yeah, there wasn't 205 00:07:47,964 --> 00:07:50,370 very much static at all. But actually, when 206 00:07:50,370 --> 00:07:52,129 they then looked at how much kind of 207 00:07:52,129 --> 00:07:52,629 coffee, 208 00:07:54,449 --> 00:07:56,290 kind of dissolved into the into the water 209 00:07:56,290 --> 00:07:58,289 itself, they found actually there was much more 210 00:07:58,289 --> 00:07:58,789 consistent 211 00:07:59,250 --> 00:08:01,410 and a lot stronger brew than that resulted. 212 00:08:01,410 --> 00:08:03,845 So so if you do actually manage to, 213 00:08:04,464 --> 00:08:06,545 grind your beans at home, if you just 214 00:08:06,545 --> 00:08:08,064 add a little kind of splash, just a 215 00:08:08,064 --> 00:08:09,904 drop or so of water, you know, you 216 00:08:09,904 --> 00:08:11,185 may find that, 217 00:08:11,985 --> 00:08:13,584 that, you know, that the coffee is much 218 00:08:13,584 --> 00:08:15,345 more consistent as a result. And of course, 219 00:08:15,345 --> 00:08:16,084 like coffee 220 00:08:16,520 --> 00:08:19,240 is it is a very experimental beverage. You 221 00:08:19,240 --> 00:08:21,560 know, there's lots of different parameters you can 222 00:08:21,560 --> 00:08:23,180 change. You know, you can change the 223 00:08:23,960 --> 00:08:25,259 size of the coffee grounds, 224 00:08:27,000 --> 00:08:28,139 the amount of water, 225 00:08:28,884 --> 00:08:29,705 the temperature. 226 00:08:30,324 --> 00:08:32,264 There's lots of different things you can, 227 00:08:32,725 --> 00:08:34,245 change. So actually when I had a chat 228 00:08:34,245 --> 00:08:34,565 with, 229 00:08:35,524 --> 00:08:36,345 Christopher Hendon, 230 00:08:37,605 --> 00:08:40,504 about, you know, about how to improve your 231 00:08:40,899 --> 00:08:43,059 coffee extracting technique. You know, he was saying 232 00:08:43,059 --> 00:08:44,740 that it's very difficult because there are so 233 00:08:44,740 --> 00:08:47,059 many parameters to change. That basically is a 234 00:08:47,059 --> 00:08:48,580 way of just, you know, you kind of 235 00:08:48,580 --> 00:08:49,940 almost have to test it out yourself, you 236 00:08:49,940 --> 00:08:51,159 know, you change one of the parameters, 237 00:08:51,539 --> 00:08:52,519 see what the resulting 238 00:08:53,379 --> 00:08:55,139 brew is like, the output is like, you 239 00:08:55,139 --> 00:08:56,695 know, and then if it is something to 240 00:08:56,695 --> 00:08:58,054 your taste, then, you know, maybe you can 241 00:08:58,054 --> 00:08:59,575 tweak something else. You know, so it's kind 242 00:08:59,575 --> 00:09:01,754 of about playing around a little bit. Yeah. 243 00:09:02,215 --> 00:09:04,855 Yeah. I mean, one interesting thing about coffee, 244 00:09:04,855 --> 00:09:06,534 and I suppose you allude to it in 245 00:09:06,534 --> 00:09:08,695 the book, is that there's also different types 246 00:09:08,695 --> 00:09:11,419 of coffee makers, isn't there? And they all 247 00:09:11,419 --> 00:09:13,820 seem to work in in different ways. You 248 00:09:13,820 --> 00:09:15,980 know, for example, I'm a big fan of 249 00:09:15,980 --> 00:09:18,000 the, you know, the classic Melita 250 00:09:18,539 --> 00:09:19,039 filter, 251 00:09:19,500 --> 00:09:21,179 where you stick the filter on top of 252 00:09:21,179 --> 00:09:23,019 the cup and you pour in your boiling 253 00:09:23,019 --> 00:09:23,519 water, 254 00:09:23,985 --> 00:09:26,384 and you get your coffee. And I think 255 00:09:26,384 --> 00:09:28,544 I think I read somewhere that that's how, 256 00:09:28,544 --> 00:09:31,365 you know, professional coffee tasters, that's how they 257 00:09:31,904 --> 00:09:33,345 judge a coffee. They use, 258 00:09:33,904 --> 00:09:36,304 like a traditional paper filter. But then you've 259 00:09:36,304 --> 00:09:36,784 got, 260 00:09:37,460 --> 00:09:39,539 you know, you've got your your the the 261 00:09:39,539 --> 00:09:41,539 sort of espresso maker that you have at 262 00:09:41,539 --> 00:09:44,200 a cafe where the the steam is forced 263 00:09:44,259 --> 00:09:44,759 downwards 264 00:09:45,460 --> 00:09:48,100 into the coffee. But then you've got the, 265 00:09:48,100 --> 00:09:49,960 you know, the the classic stovetop. 266 00:09:50,475 --> 00:09:52,794 Is it called a mocha? Moka pot. Moka 267 00:09:52,794 --> 00:09:54,654 pot. Where the steam comes up. 268 00:09:55,194 --> 00:09:57,914 And, you know, it's and then you've got 269 00:09:57,914 --> 00:09:58,235 other 270 00:09:59,115 --> 00:10:01,514 well, the press and all these other sort 271 00:10:01,514 --> 00:10:03,754 of crazy ways of making coffee. And, I 272 00:10:03,754 --> 00:10:05,294 mean, it sounds to me like, 273 00:10:05,990 --> 00:10:08,250 you know, in a sense, if I know 274 00:10:08,870 --> 00:10:10,409 how I like the coffee, 275 00:10:10,949 --> 00:10:13,209 I'm not I'm not sort of being 276 00:10:13,829 --> 00:10:17,029 fusty or frumpy or picky about how I 277 00:10:17,029 --> 00:10:19,049 make it because there's so many different variables 278 00:10:19,110 --> 00:10:19,610 that 279 00:10:19,955 --> 00:10:22,195 I know how I like it, and I 280 00:10:22,195 --> 00:10:24,115 know the coffee that I use, and the 281 00:10:24,115 --> 00:10:25,815 the filter gives me the best 282 00:10:26,434 --> 00:10:27,414 coffee possible. 283 00:10:28,195 --> 00:10:30,355 Yeah. That's right. I mean, actually, Christopher Hendon, 284 00:10:30,355 --> 00:10:32,595 he actually uses the, filter as well. That 285 00:10:32,595 --> 00:10:34,754 was his actually preferred way of, so maybe 286 00:10:34,754 --> 00:10:36,329 there is something in that. But when you 287 00:10:36,329 --> 00:10:37,610 talk about the yeah. The moka pot is 288 00:10:37,610 --> 00:10:38,909 an interesting one because 289 00:10:39,370 --> 00:10:41,449 it's actually quite the physics that happens in 290 00:10:41,449 --> 00:10:43,069 a moka pot is actually really complex, 291 00:10:43,449 --> 00:10:45,389 because you have this kind of different, 292 00:10:46,329 --> 00:10:47,929 you got the temperature of the water, but 293 00:10:47,929 --> 00:10:49,595 then you got the the steam the pre 294 00:10:49,674 --> 00:10:51,434 the pressure of the steam, kind of the 295 00:10:51,434 --> 00:10:53,355 vapor pressure of the steam pushing the water 296 00:10:53,355 --> 00:10:55,754 up. But then it actually changes that kind 297 00:10:55,754 --> 00:10:58,394 of the granular nature of the coffee bed 298 00:10:58,394 --> 00:10:58,894 itself. 299 00:10:59,514 --> 00:11:02,394 So, actually, researchers have also studied, the moka 300 00:11:02,394 --> 00:11:04,414 pot in in various detail. 301 00:11:05,250 --> 00:11:07,649 One interesting thing about it was that when 302 00:11:07,649 --> 00:11:08,149 they 303 00:11:08,769 --> 00:11:10,610 so when they put cold water in the 304 00:11:10,610 --> 00:11:12,370 in the bottom compartment and then put it 305 00:11:12,370 --> 00:11:15,330 on the stove, then heated it, and then, 306 00:11:15,730 --> 00:11:17,595 obviously what kind of the output was, 307 00:11:18,554 --> 00:11:20,814 when they actually took the temperature of the 308 00:11:20,954 --> 00:11:22,714 the output, it was only about the output 309 00:11:22,714 --> 00:11:23,855 water as a coffee. 310 00:11:24,475 --> 00:11:26,314 It was actually on it wasn't actually very 311 00:11:26,314 --> 00:11:28,334 high in terms of the actual temperature itself. 312 00:11:29,434 --> 00:11:31,694 And then they reflect on that that maybe 313 00:11:31,754 --> 00:11:33,879 it wasn't extracting as much of the coffee 314 00:11:33,879 --> 00:11:35,720 as it could have done. So instead, what 315 00:11:35,720 --> 00:11:38,279 they did was they heated the temperature, the 316 00:11:38,279 --> 00:11:40,679 initial temperature. So instead of putting cold water 317 00:11:40,679 --> 00:11:42,460 in, they put kind of, you know, 318 00:11:43,559 --> 00:11:46,220 temperature water of about 40 degrees or so. 319 00:11:46,365 --> 00:11:48,044 And then they actually found that a lot 320 00:11:48,044 --> 00:11:50,284 more coffee was dissolved if they did it 321 00:11:50,284 --> 00:11:50,865 that way. 322 00:11:51,644 --> 00:11:54,125 So one tip could be to actually don't 323 00:11:54,125 --> 00:11:55,565 use cold water in a mock up, but 324 00:11:55,565 --> 00:11:57,105 actually use, you know, 325 00:11:58,125 --> 00:12:00,205 like lukewarm water or something like that. I 326 00:12:00,205 --> 00:12:02,459 I could find it very difficult to convince 327 00:12:02,459 --> 00:12:03,199 some people 328 00:12:03,659 --> 00:12:04,480 about that. 329 00:12:05,579 --> 00:12:07,980 Actually, you know, moving right along to tea. 330 00:12:07,980 --> 00:12:08,879 And of course, 331 00:12:09,259 --> 00:12:11,259 you know, I think, a lot of people 332 00:12:11,259 --> 00:12:14,059 would be outraged if you put hot water 333 00:12:14,059 --> 00:12:16,065 into your kettle to make a cup of 334 00:12:16,065 --> 00:12:18,964 tea. You you also look at the teapot 335 00:12:19,105 --> 00:12:20,884 effect, which is sort of a dribble 336 00:12:21,345 --> 00:12:23,904 of of liquid that comes down the spout 337 00:12:23,904 --> 00:12:25,125 and, you know, annoyingly 338 00:12:25,745 --> 00:12:28,704 goes onto your countertop or tablecloth or or 339 00:12:28,704 --> 00:12:29,204 whatever. 340 00:12:30,289 --> 00:12:31,589 And and 341 00:12:31,889 --> 00:12:34,549 one of the takeaways from from that anecdote 342 00:12:34,850 --> 00:12:35,509 is that 343 00:12:35,889 --> 00:12:37,509 gravity is not a factor 344 00:12:38,129 --> 00:12:40,690 in the production of this dribble, and it 345 00:12:40,690 --> 00:12:41,350 would happen 346 00:12:41,730 --> 00:12:43,845 in outer space. I suppose, you know, the 347 00:12:43,845 --> 00:12:45,225 the the English, 348 00:12:45,845 --> 00:12:47,764 astronaut Tim Peake, when he has his cup 349 00:12:47,764 --> 00:12:48,644 of tea, would, 350 00:12:49,284 --> 00:12:51,524 would produce a dribble. And and so so 351 00:12:51,524 --> 00:12:53,444 why is I I I find it difficult 352 00:12:53,684 --> 00:12:56,644 hard to understand why gravity isn't involved in 353 00:12:56,644 --> 00:13:00,309 this dribbling process. Apparently, with the teapot effect, 354 00:13:01,490 --> 00:13:02,950 the way gravity actually 355 00:13:04,210 --> 00:13:06,290 affects the teapot effect is where it actually 356 00:13:06,290 --> 00:13:07,509 detaches from 357 00:13:07,889 --> 00:13:09,970 the the spout itself. So it's not effect 358 00:13:10,050 --> 00:13:11,884 it's not an effect of actually the teapot 359 00:13:11,884 --> 00:13:14,205 effect in terms of dribbling down. It's more 360 00:13:14,205 --> 00:13:16,445 about where it might detach from the underside 361 00:13:16,445 --> 00:13:18,144 of the spout and then dribble down. 362 00:13:19,245 --> 00:13:20,924 But, yeah, the teapot effect is something I 363 00:13:20,924 --> 00:13:22,845 think it was like the nineteen fifties where 364 00:13:22,845 --> 00:13:24,870 researchers started working on that. 365 00:13:25,589 --> 00:13:27,450 And they discovered then it was various 366 00:13:27,830 --> 00:13:30,649 effects such as, like, surface tension, etcetera, 367 00:13:31,350 --> 00:13:32,389 that was behind it. 368 00:13:33,110 --> 00:13:34,870 But it's only anti in recent years, I 369 00:13:34,870 --> 00:13:36,649 think in the February 370 00:13:36,710 --> 00:13:37,210 where, 371 00:13:38,295 --> 00:13:39,975 I remember seeing the paper itself actually when 372 00:13:39,975 --> 00:13:41,894 it was released where it said researchers have 373 00:13:41,894 --> 00:13:43,894 come up with an ideal version of the 374 00:13:43,894 --> 00:13:45,995 teapot effect where they've solved it at last. 375 00:13:46,934 --> 00:13:49,375 And basically that what they found was this 376 00:13:49,575 --> 00:13:51,175 the teapot effect is not so much about 377 00:13:51,175 --> 00:13:52,634 gravity, but it's more about 378 00:13:52,959 --> 00:13:55,279 surface tension, actually the capillary effect as well, 379 00:13:55,279 --> 00:13:57,440 like another way. But, actually, the physics of 380 00:13:57,440 --> 00:13:58,980 the teapot effect is actually 381 00:13:59,360 --> 00:14:01,120 quite complicated, and it's, 382 00:14:01,600 --> 00:14:03,519 quite involved in terms of what the actual 383 00:14:03,519 --> 00:14:05,894 process processes are going on. But the but 384 00:14:05,894 --> 00:14:07,975 that that they effectively found that this was 385 00:14:07,975 --> 00:14:09,514 a a universal theorem 386 00:14:10,134 --> 00:14:11,815 of the teapot effect and now the, 387 00:14:12,455 --> 00:14:15,014 teapot effect is solved. But as you mentioned 388 00:14:15,014 --> 00:14:15,735 before about, 389 00:14:16,455 --> 00:14:18,389 you know, the kettles, one of the 390 00:14:18,870 --> 00:14:20,889 one of the interesting aspects of the the 391 00:14:21,110 --> 00:14:23,190 the noise the kettle whistle. So the noise 392 00:14:23,190 --> 00:14:25,509 that's produced during the boiling during a kettle, 393 00:14:25,509 --> 00:14:27,830 which is quite an interesting area. And that 394 00:14:27,830 --> 00:14:28,070 was, 395 00:14:29,269 --> 00:14:31,350 that was a a researcher in Cambridge, actually, 396 00:14:31,350 --> 00:14:33,450 who just who who found out 397 00:14:33,845 --> 00:14:36,105 that basically no one had really ever studied 398 00:14:37,045 --> 00:14:40,085 how the noise in the teapot whistle was 399 00:14:40,085 --> 00:14:41,285 produced. You know, it was like one of 400 00:14:41,285 --> 00:14:42,725 these things that, you know, people just heard 401 00:14:42,804 --> 00:14:45,045 have heard it for decades, but no one 402 00:14:45,045 --> 00:14:46,884 really knew how it was actually produced. So 403 00:14:46,884 --> 00:14:48,644 he looked at it in great detail with, 404 00:14:48,644 --> 00:14:49,139 you know, 405 00:14:49,700 --> 00:14:50,200 various, 406 00:14:50,820 --> 00:14:52,360 microphones and cameras, etcetera. 407 00:14:52,899 --> 00:14:56,580 And what they discovered actually was that basically 408 00:14:56,580 --> 00:14:59,000 when this this kind of stream of steam 409 00:14:59,059 --> 00:15:01,080 goes through the teapot whistle, 410 00:15:02,195 --> 00:15:04,375 It enters the first so the teapot whistle 411 00:15:04,435 --> 00:15:06,915 is basically two plates with a small circular 412 00:15:06,915 --> 00:15:08,134 hole in each of the plate. 413 00:15:08,995 --> 00:15:11,235 So that kind of steam initially goes through 414 00:15:11,235 --> 00:15:13,095 that little hole, and then 415 00:15:14,149 --> 00:15:16,070 it kind of enters into a jet basically 416 00:15:16,070 --> 00:15:18,070 when he goes through this first hole. But 417 00:15:18,070 --> 00:15:20,550 that's not actually the the actual sound that's 418 00:15:20,550 --> 00:15:22,470 produced that you hear isn't produced in that 419 00:15:22,470 --> 00:15:22,970 cavity. 420 00:15:23,509 --> 00:15:25,269 What they actually found is that that when 421 00:15:25,269 --> 00:15:27,190 the steam then goes through the second hole, 422 00:15:27,190 --> 00:15:29,050 it kind of then turns into vortices. 423 00:15:29,504 --> 00:15:30,725 So this kind of jet 424 00:15:31,665 --> 00:15:34,144 powers out of the second hole, produces these 425 00:15:34,144 --> 00:15:36,384 kind of vortices, and that is actually where 426 00:15:36,384 --> 00:15:38,004 the noise is actually produced. 427 00:15:38,384 --> 00:15:40,565 And that's a technique called vortex shedding. 428 00:15:41,184 --> 00:15:42,725 So it's actually the same physics 429 00:15:43,105 --> 00:15:43,470 that 430 00:15:43,949 --> 00:15:46,509 happens when you have, like, telegraph wires in 431 00:15:46,509 --> 00:15:47,169 the wind. 432 00:15:47,549 --> 00:15:48,669 They're kind of, like, moving in the wind, 433 00:15:48,669 --> 00:15:50,350 and they might be, like, producing a noise. 434 00:15:50,350 --> 00:15:51,169 Oh, yeah. 435 00:15:51,549 --> 00:15:53,709 So I checked exactly the same effect as 436 00:15:53,709 --> 00:15:55,089 what's happening in the teapot, 437 00:15:55,709 --> 00:15:56,209 whistle. 438 00:15:56,574 --> 00:15:58,095 And it's the same thing that you might 439 00:15:58,095 --> 00:15:59,214 hear, like, you know, if you're driving a 440 00:15:59,214 --> 00:16:00,894 little motorway and you have roof bars on 441 00:16:00,894 --> 00:16:02,654 top of your car, and it produces that 442 00:16:02,654 --> 00:16:05,134 characteristic whistling noise from the roof bars. It's 443 00:16:05,134 --> 00:16:07,454 the same, like vortex shedding. So where this 444 00:16:07,454 --> 00:16:10,095 kind of kind of wind is passing over 445 00:16:10,095 --> 00:16:12,179 a certain object and they're producing these kind 446 00:16:12,179 --> 00:16:12,759 of vortices 447 00:16:13,379 --> 00:16:14,659 that produce a noise. But it's, yeah, it's 448 00:16:14,659 --> 00:16:16,899 just really fascinating kind of research. You know, 449 00:16:16,899 --> 00:16:18,980 that's kind of a classic example of this 450 00:16:18,980 --> 00:16:19,799 kind of everyday, 451 00:16:20,339 --> 00:16:22,259 you know, phenomena. And then you kind of, 452 00:16:22,259 --> 00:16:24,259 like, find new things about, you know, how 453 00:16:24,259 --> 00:16:26,375 to build things like that. And and sort 454 00:16:26,375 --> 00:16:27,115 of moving 455 00:16:27,495 --> 00:16:30,235 on, into I suppose you've had your breakfast 456 00:16:30,615 --> 00:16:30,934 and, 457 00:16:32,535 --> 00:16:34,774 you know, you're moving on to shave. I 458 00:16:34,774 --> 00:16:37,014 don't know. Either your face or your legs 459 00:16:37,014 --> 00:16:37,754 or both. 460 00:16:38,990 --> 00:16:39,490 And 461 00:16:39,790 --> 00:16:40,769 you've got something 462 00:16:41,309 --> 00:16:43,710 about razors. And I I can remember when 463 00:16:43,710 --> 00:16:44,450 this story, 464 00:16:45,389 --> 00:16:45,889 appeared, 465 00:16:46,350 --> 00:16:48,590 on the Physics World website, so it made 466 00:16:48,590 --> 00:16:50,769 me laugh to see it again. And, 467 00:16:51,565 --> 00:16:53,644 basically, the question is, well, you know, a 468 00:16:53,644 --> 00:16:56,065 razor is made out of a very hard 469 00:16:56,285 --> 00:16:57,185 piece of steel. 470 00:16:57,644 --> 00:17:00,945 And so how on earth do fairly soft 471 00:17:01,004 --> 00:17:01,504 whiskers 472 00:17:02,125 --> 00:17:02,865 or hairs 473 00:17:03,325 --> 00:17:06,410 dull the razor? And I I can remember 474 00:17:06,410 --> 00:17:08,890 when this story went up on the on 475 00:17:08,890 --> 00:17:09,630 the on the website. 476 00:17:10,009 --> 00:17:11,789 And at that time, we had comments 477 00:17:12,410 --> 00:17:14,109 on the website. We don't anymore. 478 00:17:14,650 --> 00:17:14,970 But, 479 00:17:15,450 --> 00:17:17,210 you know, I remember this story went up, 480 00:17:17,210 --> 00:17:18,589 and it gave this wonderful 481 00:17:19,375 --> 00:17:19,875 explanation. 482 00:17:20,494 --> 00:17:22,654 And somebody wrote in and said, oh, you're 483 00:17:22,654 --> 00:17:23,554 you're being dozy. 484 00:17:23,855 --> 00:17:25,615 The reason they get dull is so they 485 00:17:25,615 --> 00:17:26,914 can sell more razors. 486 00:17:27,214 --> 00:17:29,855 Exactly. And I thought, okay. I can't argue 487 00:17:29,855 --> 00:17:30,914 with that. So, 488 00:17:31,529 --> 00:17:33,450 yeah, I suppose there might be some truth 489 00:17:33,450 --> 00:17:35,690 to that. But why why on earth does 490 00:17:35,690 --> 00:17:36,990 a a very, very sharp, 491 00:17:37,850 --> 00:17:38,570 and and, 492 00:17:39,130 --> 00:17:40,590 hard piece of metal 493 00:17:41,049 --> 00:17:44,009 get dulled by, you know, a fairly soft 494 00:17:44,009 --> 00:17:44,984 piece of hair? 495 00:17:45,464 --> 00:17:46,904 Yeah. So that's what another one of these 496 00:17:46,904 --> 00:17:48,444 life's mysteries, isn't it? 497 00:17:49,065 --> 00:17:50,204 Yes. A razor blade's, 498 00:17:50,744 --> 00:17:53,144 mostly made of steel. And, of course, the 499 00:17:53,144 --> 00:17:55,704 actual hairs on your face, they're around 50 500 00:17:55,704 --> 00:17:56,765 times softer 501 00:17:57,384 --> 00:17:59,704 than the materials of razor blade itself. So 502 00:17:59,704 --> 00:18:02,619 you might think, how on earth does something 503 00:18:02,619 --> 00:18:04,400 that's 50 times softer end 504 00:18:04,700 --> 00:18:05,279 up blunting, 505 00:18:06,059 --> 00:18:07,740 you know, something that's so hard such as 506 00:18:07,740 --> 00:18:08,640 a razor blade? 507 00:18:09,100 --> 00:18:11,440 And that's what these researchers at at MIT, 508 00:18:11,980 --> 00:18:12,859 in The US, 509 00:18:13,674 --> 00:18:15,375 were very keen to understand. 510 00:18:16,555 --> 00:18:17,375 So they actually, 511 00:18:17,674 --> 00:18:19,775 carried out a number of experiments, 512 00:18:20,954 --> 00:18:22,255 in which, you know, 513 00:18:22,555 --> 00:18:23,055 kind, 514 00:18:23,674 --> 00:18:24,974 students plucked 515 00:18:25,595 --> 00:18:26,734 individual hers 516 00:18:27,035 --> 00:18:29,669 from their face, and then they got this 517 00:18:29,669 --> 00:18:31,529 blade basically to cut, 518 00:18:32,069 --> 00:18:33,669 just a single or very few, you know, 519 00:18:33,669 --> 00:18:35,929 very few strands of of hair itself. 520 00:18:36,789 --> 00:18:39,029 And they looked under that at that process 521 00:18:39,029 --> 00:18:41,450 under a microscope, you know, very powerful microscope. 522 00:18:42,149 --> 00:18:44,825 But they were amazed to discover that even 523 00:18:44,825 --> 00:18:47,724 single hairs like that could actually end up, 524 00:18:48,265 --> 00:18:48,765 chipping, 525 00:18:49,464 --> 00:18:51,224 the blades themselves when you look under, you 526 00:18:51,224 --> 00:18:51,884 know, very, 527 00:18:52,705 --> 00:18:53,724 you know, very, 528 00:18:54,184 --> 00:18:55,085 powerful microscope. 529 00:18:56,025 --> 00:18:57,325 So that kind of really 530 00:18:57,839 --> 00:18:59,519 surprised them about how on earth, you know, 531 00:18:59,519 --> 00:19:02,179 what is the process that's happening to, you 532 00:19:02,319 --> 00:19:04,339 know, such that a hair can actually blunt 533 00:19:04,720 --> 00:19:05,299 a blade. 534 00:19:06,160 --> 00:19:07,359 So they looked at it in much more 535 00:19:07,359 --> 00:19:09,440 detail. They got, did a lot more experiments 536 00:19:09,440 --> 00:19:12,015 on it. And they actually discovered there was 537 00:19:12,015 --> 00:19:13,875 kind of three different types, 538 00:19:15,214 --> 00:19:17,214 of process that was happening when a when 539 00:19:17,214 --> 00:19:18,355 a hair was being cut. 540 00:19:18,894 --> 00:19:20,755 So one example is, 541 00:19:21,535 --> 00:19:22,174 where the hair 542 00:19:22,859 --> 00:19:24,960 basically there's like, there may be small imperfections 543 00:19:25,339 --> 00:19:27,660 in the blade itself during the manufacturing process 544 00:19:27,660 --> 00:19:29,339 where you have little cracks, so it's kind 545 00:19:29,339 --> 00:19:31,500 of really unavoidable that you've got these kind 546 00:19:31,500 --> 00:19:33,200 of small imperfections. 547 00:19:33,660 --> 00:19:35,119 So if a hair kind of then 548 00:19:35,420 --> 00:19:37,904 slightly hits one was a crack, it's like 549 00:19:37,984 --> 00:19:40,325 kind of slightly hits one side of it, 550 00:19:40,544 --> 00:19:43,424 that is enough to eventually kind of chip 551 00:19:43,424 --> 00:19:44,944 the blade if it hits if it is 552 00:19:44,944 --> 00:19:46,005 a side of a crack. 553 00:19:46,464 --> 00:19:46,964 Another 554 00:19:47,505 --> 00:19:50,625 possibility is that in the angle itself, so 555 00:19:50,625 --> 00:19:51,265 if a 556 00:19:51,829 --> 00:19:54,470 if the blade is kind of perpendicular to 557 00:19:54,470 --> 00:19:55,769 the hair, it should generally 558 00:19:56,150 --> 00:19:57,210 avoid cracking 559 00:19:57,910 --> 00:19:58,569 or chipping. 560 00:19:59,269 --> 00:20:01,349 But if the angle is actually an if 561 00:20:01,349 --> 00:20:01,849 the, 562 00:20:02,470 --> 00:20:04,569 blade is an angle to the hair 563 00:20:04,984 --> 00:20:07,025 itself, then that can actually that also could 564 00:20:07,144 --> 00:20:08,984 they found it could also result in in 565 00:20:08,984 --> 00:20:09,484 chipping. 566 00:20:09,865 --> 00:20:10,605 And another, 567 00:20:10,904 --> 00:20:11,945 the third option, 568 00:20:12,345 --> 00:20:14,424 that they that they discovered was actually kind 569 00:20:14,424 --> 00:20:15,565 of, inconsistencies 570 00:20:15,945 --> 00:20:18,045 in the material itself. So in in homogeneities 571 00:20:18,505 --> 00:20:19,484 basically where 572 00:20:19,960 --> 00:20:22,440 the material was kind of softer, say, in 573 00:20:22,440 --> 00:20:24,059 one part than it was in the other. 574 00:20:24,440 --> 00:20:26,200 So if, again, if the hair was then 575 00:20:26,440 --> 00:20:28,840 if the hair hit that softer part, it 576 00:20:28,840 --> 00:20:30,700 would then basically end up chipping, 577 00:20:31,400 --> 00:20:32,059 the blade. 578 00:20:33,005 --> 00:20:34,764 So that's what they discovered. They discovered these 579 00:20:34,764 --> 00:20:35,264 three, 580 00:20:36,284 --> 00:20:38,464 these three kind of processes that are happening. 581 00:20:38,684 --> 00:20:41,005 But when it comes to, as you mentioned 582 00:20:41,005 --> 00:20:43,484 before about, you know, does the actual industry 583 00:20:43,484 --> 00:20:44,784 want this to kind of happen, 584 00:20:45,990 --> 00:20:48,309 one way of getting around it is to 585 00:20:48,309 --> 00:20:50,590 have is to produce a material that's more 586 00:20:50,710 --> 00:20:52,869 much more consistent. So it doesn't have those 587 00:20:52,869 --> 00:20:55,430 certain kind of softer and harder regions. You 588 00:20:55,430 --> 00:20:56,330 know, it's more, 589 00:20:57,109 --> 00:20:58,650 more, I mean, homogeneous, 590 00:20:59,975 --> 00:21:01,975 so that the that those kind of chips 591 00:21:01,975 --> 00:21:04,855 won't happen. But in terms of actually for, 592 00:21:04,855 --> 00:21:06,855 you know, stopping the chips altogether, it's gonna 593 00:21:06,855 --> 00:21:08,934 be very difficult because you will always have 594 00:21:08,934 --> 00:21:10,394 these kind of little cracks 595 00:21:11,174 --> 00:21:13,434 in the material itself, which will then 596 00:21:13,950 --> 00:21:15,950 even be even, you know, hers can end 597 00:21:15,950 --> 00:21:17,630 up chipping, you know, end up chipping those 598 00:21:17,630 --> 00:21:18,130 blades. 599 00:21:18,669 --> 00:21:20,629 But actually the researchers at MIT are actually 600 00:21:20,629 --> 00:21:22,450 at the moment, they're they're developing 601 00:21:22,829 --> 00:21:24,450 new materials, which are, 602 00:21:24,909 --> 00:21:25,724 you know, more 603 00:21:26,044 --> 00:21:26,865 more consistent, 604 00:21:27,404 --> 00:21:29,404 in the blade. And I think, from what 605 00:21:29,404 --> 00:21:30,684 I heard, anyway, is that they, you know, 606 00:21:30,684 --> 00:21:32,625 they are looking at developing products where, 607 00:21:33,565 --> 00:21:35,484 you know, blades could be more consistent, and 608 00:21:35,484 --> 00:21:37,884 that may end up, you know, increasing the 609 00:21:37,884 --> 00:21:38,384 lifetime 610 00:21:38,899 --> 00:21:40,740 of certain blades. Right. But but, of course, 611 00:21:40,740 --> 00:21:42,119 that was kind of, like, you know, disposables, 612 00:21:42,179 --> 00:21:43,480 etcetera. I mean, you could 613 00:21:43,859 --> 00:21:45,380 you could use a blade where you sharpen 614 00:21:45,380 --> 00:21:47,299 it. That's one option of getting around it, 615 00:21:47,299 --> 00:21:49,480 where you would purposely sharpen the blade. 616 00:21:50,179 --> 00:21:52,394 Like an old fashioned straight razor. Exactly. An 617 00:21:52,394 --> 00:21:54,315 old fashioned straight razor would get around that 618 00:21:54,315 --> 00:21:55,994 problem because it would then end up, you 619 00:21:55,994 --> 00:21:56,494 know, 620 00:21:56,954 --> 00:21:58,714 making it much more sharper each time. 621 00:21:59,194 --> 00:22:00,714 But yeah, that was quite an interesting, 622 00:22:01,835 --> 00:22:03,914 discovery actually, but there's kind of different ways 623 00:22:03,914 --> 00:22:04,414 of 624 00:22:04,799 --> 00:22:06,799 of firing us. And the same goes for 625 00:22:06,799 --> 00:22:09,360 things like cutting a cutting a knife through 626 00:22:09,360 --> 00:22:11,680 cheese. It's just exactly the same process, though, 627 00:22:11,680 --> 00:22:14,880 where effectively cheese itself could blunt a knife. 628 00:22:14,880 --> 00:22:16,400 And it's the same very same things, 629 00:22:16,960 --> 00:22:18,580 but these kind of small imperfections 630 00:22:18,960 --> 00:22:21,494 can result in, you know, a failure of, 631 00:22:22,055 --> 00:22:24,134 even something so hard as a a steel 632 00:22:24,134 --> 00:22:24,634 knife. 633 00:22:25,335 --> 00:22:27,335 And and sort of staying on the, on 634 00:22:27,335 --> 00:22:28,555 the subject of hair, 635 00:22:28,934 --> 00:22:31,095 you you you also look at, 636 00:22:32,055 --> 00:22:33,275 runners' ponytails. 637 00:22:34,230 --> 00:22:35,589 And I think, you you know, if you've 638 00:22:35,589 --> 00:22:37,529 seen someone with a ponytail running, 639 00:22:37,990 --> 00:22:40,789 normally the ponytail sort of swings back and 640 00:22:40,789 --> 00:22:41,289 forth. 641 00:22:42,069 --> 00:22:42,569 And 642 00:22:43,349 --> 00:22:45,269 if you think about it, a runner is 643 00:22:45,269 --> 00:22:46,890 sort of going up and down. 644 00:22:47,204 --> 00:22:49,065 So why isn't their ponytail 645 00:22:49,444 --> 00:22:49,944 oscillating 646 00:22:51,284 --> 00:22:52,105 in the horizontal 647 00:22:52,484 --> 00:22:55,565 direction rather than the the vertical direction? But 648 00:22:55,565 --> 00:22:55,924 the 649 00:22:56,404 --> 00:22:58,664 clearly, there's some sort of coupling going on 650 00:22:58,964 --> 00:22:59,464 between, 651 00:22:59,765 --> 00:23:02,089 those two degrees of freedom. So what what's 652 00:23:02,089 --> 00:23:05,289 happening there, Michael? Why do runners' ponytails go 653 00:23:05,289 --> 00:23:07,789 side to side rather than up and down? 654 00:23:08,089 --> 00:23:10,269 Yes. It's actually not only I mean, ponytails 655 00:23:10,329 --> 00:23:12,730 is one possibility, but also, like, if you 656 00:23:12,730 --> 00:23:14,490 have flight if you find you have, like, 657 00:23:14,490 --> 00:23:16,424 a hoodie on sale, which has got 658 00:23:16,805 --> 00:23:18,724 tassels, you'll find exactly the same thing. So 659 00:23:18,724 --> 00:23:19,545 if you walk 660 00:23:20,085 --> 00:23:21,865 at a at a brisk pace, 661 00:23:22,325 --> 00:23:24,105 you might find as you're walking, 662 00:23:24,404 --> 00:23:25,705 the tassels on your hoodie 663 00:23:26,644 --> 00:23:28,884 are not swinging off, like, you know, back 664 00:23:28,884 --> 00:23:30,484 and forth, but actually swinging from side to 665 00:23:30,484 --> 00:23:32,200 side. So you're kind of thinking exactly as 666 00:23:32,200 --> 00:23:32,859 you said, 667 00:23:33,400 --> 00:23:34,299 how on earth, 668 00:23:34,599 --> 00:23:35,960 when when your head is, you know, head 669 00:23:35,960 --> 00:23:37,099 is moving up and down, 670 00:23:37,400 --> 00:23:39,159 you know, why why is your your body 671 00:23:39,159 --> 00:23:41,240 moving forward, and why are the tassels moving 672 00:23:41,240 --> 00:23:43,259 from from side to side? 673 00:23:44,134 --> 00:23:46,054 And it's actually a bit of a strange 674 00:23:46,054 --> 00:23:47,254 story behind it, but it was, 675 00:23:48,855 --> 00:23:51,095 it was someone who was actually working on 676 00:23:51,095 --> 00:23:53,575 the kind of three body problem in terms 677 00:23:53,575 --> 00:23:54,154 of the, 678 00:23:55,014 --> 00:23:56,075 in terms of astronomy 679 00:23:56,500 --> 00:23:59,000 and kind of the relationship between the sun, 680 00:23:59,380 --> 00:24:01,220 the earth, and the moon. And it was, 681 00:24:01,859 --> 00:24:04,659 various kind of equations that they produce from 682 00:24:04,659 --> 00:24:05,159 that. 683 00:24:05,700 --> 00:24:07,779 And somehow that could actually then be used 684 00:24:07,779 --> 00:24:09,220 in terms of the physics of how a 685 00:24:09,220 --> 00:24:10,659 ponytail moves. And it's to do with a 686 00:24:10,659 --> 00:24:12,884 couple as you mentioned, the couplings between 687 00:24:13,265 --> 00:24:15,904 the the kind of what's swinging and then 688 00:24:15,904 --> 00:24:17,605 what's its kind of anchor point. 689 00:24:17,984 --> 00:24:20,304 So they discovered that if there's kind of 690 00:24:20,304 --> 00:24:20,704 a, 691 00:24:21,265 --> 00:24:21,924 the frequency 692 00:24:22,384 --> 00:24:22,884 is 693 00:24:23,424 --> 00:24:24,164 a doubling. 694 00:24:25,210 --> 00:24:27,049 So say if you're walking, you've got a 695 00:24:27,049 --> 00:24:28,890 certain frequency that your head is moving up 696 00:24:28,890 --> 00:24:29,710 and down, your, 697 00:24:30,809 --> 00:24:32,429 your body's moving up and down. 698 00:24:32,809 --> 00:24:34,890 If there's kind of a relationship between the 699 00:24:35,210 --> 00:24:37,049 between that length and actually the length of 700 00:24:37,049 --> 00:24:38,269 the ponytail itself, 701 00:24:38,815 --> 00:24:40,575 then basically, if it's if it's if it's 702 00:24:40,575 --> 00:24:43,154 a double wing, then basically any small 703 00:24:43,695 --> 00:24:44,195 deviation 704 00:24:45,455 --> 00:24:45,955 between 705 00:24:46,575 --> 00:24:48,494 that up and down movement and side to 706 00:24:48,494 --> 00:24:52,099 side, basically then it it expands, basically. So 707 00:24:52,099 --> 00:24:54,359 if you've got a very tiny deviation 708 00:24:55,059 --> 00:24:57,320 that you're slightly going to the side, 709 00:24:57,940 --> 00:25:00,840 what happens is that basically then expands exponentially. 710 00:25:01,940 --> 00:25:03,619 So that's what you see then, basically, is 711 00:25:03,619 --> 00:25:05,220 because, you have this kind of, 712 00:25:06,654 --> 00:25:08,974 coupling in your stride length and your between 713 00:25:08,974 --> 00:25:11,234 the actual coupling of the of the ponytail 714 00:25:11,375 --> 00:25:11,875 itself, 715 00:25:12,414 --> 00:25:15,055 it's basically then it expands and you get 716 00:25:15,055 --> 00:25:15,954 this kind of, 717 00:25:17,055 --> 00:25:19,694 exponential increase in the swinging from side to 718 00:25:19,694 --> 00:25:20,994 side. It's only a very 719 00:25:21,319 --> 00:25:23,160 small thing that then results results in something 720 00:25:23,160 --> 00:25:24,700 that you actually kind of see. 721 00:25:25,559 --> 00:25:27,400 And so is there any up and down 722 00:25:27,400 --> 00:25:28,940 motion in the ponytail? 723 00:25:29,319 --> 00:25:31,799 Or is it only moving side to side? 724 00:25:31,799 --> 00:25:33,400 Or is it there's is it much more 725 00:25:33,400 --> 00:25:36,039 complicated than just going side to side? It's 726 00:25:36,039 --> 00:25:36,599 sort of going 727 00:25:37,294 --> 00:25:39,615 well, it is going up and down. Right? 728 00:25:39,615 --> 00:25:41,454 Because your head's going up. Yeah. Exactly. Because 729 00:25:41,454 --> 00:25:43,054 your head yeah. Yeah. Because your head's going 730 00:25:43,054 --> 00:25:44,434 up and down, not the link. 731 00:25:44,734 --> 00:25:46,414 So the ponytail is going, yeah, up and 732 00:25:46,414 --> 00:25:48,194 down and side to side. Yeah. But 733 00:25:48,575 --> 00:25:50,835 it's only that because you have that very 734 00:25:50,894 --> 00:25:51,394 small, 735 00:25:52,909 --> 00:25:54,349 tweak in it going side to side that 736 00:25:54,349 --> 00:25:56,450 it kind of expands and ends up going 737 00:25:56,509 --> 00:25:59,089 way, you know, really far side to side 738 00:25:59,149 --> 00:26:01,890 because of that kind of doubling relationship between, 739 00:26:02,750 --> 00:26:04,589 the frequency of the head movement and the 740 00:26:04,589 --> 00:26:06,974 and and the lens of the ponytail. So, 741 00:26:06,974 --> 00:26:08,015 yeah, it's kind of all in the mass 742 00:26:08,015 --> 00:26:10,095 of that. But, yeah, it's quite interesting that 743 00:26:10,255 --> 00:26:12,095 yeah. Something that you see when you see 744 00:26:12,095 --> 00:26:14,095 someone walking around and they're or or going 745 00:26:14,095 --> 00:26:15,934 for a run, you see their ponytail wafting 746 00:26:15,934 --> 00:26:17,214 around. It's, you know, it is all because 747 00:26:17,214 --> 00:26:17,855 of those 748 00:26:18,815 --> 00:26:20,734 it came from the mathematics of working out 749 00:26:20,734 --> 00:26:21,474 those relationships 750 00:26:21,775 --> 00:26:22,095 between, 751 00:26:22,769 --> 00:26:23,990 the sun and the moon. 752 00:26:24,450 --> 00:26:27,090 And sort of moving on from running to 753 00:26:27,090 --> 00:26:29,509 to driving a car, I mean, I think 754 00:26:29,970 --> 00:26:33,250 one thing that's really fascinated physicists for for 755 00:26:33,250 --> 00:26:34,230 years, I suppose, 756 00:26:35,410 --> 00:26:38,204 ever since the first traffic jam occurred, I 757 00:26:38,204 --> 00:26:40,944 think physicists have been fascinated as to why 758 00:26:41,164 --> 00:26:43,244 why they occur. And then, you know, there's 759 00:26:43,244 --> 00:26:45,964 a particular kind of traffic jam that I 760 00:26:45,964 --> 00:26:48,065 think any driver is familiar with. 761 00:26:48,365 --> 00:26:50,924 You're driving along, and the traffic suddenly comes 762 00:26:50,924 --> 00:26:52,625 to a halt for no good reason. 763 00:26:53,059 --> 00:26:55,299 There's no obstruction on the road, the speed 764 00:26:55,299 --> 00:26:56,599 limit hasn't changed, 765 00:26:57,539 --> 00:27:00,019 and then the traffic jam breaks up and 766 00:27:00,019 --> 00:27:02,099 you move along for, I don't know, half 767 00:27:02,099 --> 00:27:04,819 a mile, and you slow down again. And 768 00:27:04,819 --> 00:27:07,140 there doesn't seem to be any rhyme or 769 00:27:07,140 --> 00:27:09,444 reason to this. And I think when the 770 00:27:09,444 --> 00:27:10,904 physicist looks at this, 771 00:27:11,284 --> 00:27:13,144 I think they're seeing some sort 772 00:27:13,524 --> 00:27:14,825 of emergent behavior, 773 00:27:15,605 --> 00:27:17,204 some sort of there's gotta be a phase 774 00:27:17,204 --> 00:27:20,164 transition in here and, you know, lots of 775 00:27:20,164 --> 00:27:21,304 interesting mathematics. 776 00:27:22,049 --> 00:27:23,730 And, I think you look at some of 777 00:27:23,730 --> 00:27:25,889 that in the book, don't you? Yeah. That's 778 00:27:25,889 --> 00:27:27,409 right. So one of one of the issues 779 00:27:27,409 --> 00:27:29,409 is about, you know, the annoyance that you 780 00:27:29,409 --> 00:27:31,569 have on daily life of coming up against 781 00:27:31,569 --> 00:27:33,490 traffic jams, whether it's on the motorway or 782 00:27:33,490 --> 00:27:35,409 even just, you know, out and about in 783 00:27:35,409 --> 00:27:35,909 town. 784 00:27:36,924 --> 00:27:37,805 And, but one of the, yeah, one of 785 00:27:37,805 --> 00:27:40,684 the interesting aspects is how traffic jams can 786 00:27:40,684 --> 00:27:41,184 occur. 787 00:27:41,565 --> 00:27:43,964 Even when even in the absence of, you 788 00:27:43,964 --> 00:27:46,285 know, anything that you may expect can cause 789 00:27:46,285 --> 00:27:48,464 a traffic jam, such as, you know, roadworks, 790 00:27:49,420 --> 00:27:51,039 a broken down car, for example. 791 00:27:51,980 --> 00:27:55,200 You know, traffic jams can seemingly just occur 792 00:27:56,059 --> 00:27:56,960 for no reason. 793 00:27:57,340 --> 00:27:58,799 And the kind of 794 00:27:59,180 --> 00:28:01,039 reason for it is because, 795 00:28:01,580 --> 00:28:03,945 you know, even if a driver kind 796 00:28:04,565 --> 00:28:06,005 of just takes her eye off the road 797 00:28:06,005 --> 00:28:07,845 for a split second, for example, you know, 798 00:28:07,845 --> 00:28:09,445 and then just kind of a lack of 799 00:28:09,445 --> 00:28:09,945 concentration, 800 00:28:10,644 --> 00:28:12,805 what what can basically happen is that that 801 00:28:12,805 --> 00:28:14,485 that then has a kind of a spillover 802 00:28:14,485 --> 00:28:16,424 effect. So you have someone who, 803 00:28:16,940 --> 00:28:18,220 say they lack a bit of lack of 804 00:28:18,220 --> 00:28:18,720 concentration, 805 00:28:19,339 --> 00:28:20,859 might veer off a little bit to the 806 00:28:20,859 --> 00:28:21,759 road, they break, 807 00:28:22,140 --> 00:28:24,220 then the person coming behind them then has 808 00:28:24,220 --> 00:28:26,299 to react to that, they break, you know, 809 00:28:26,299 --> 00:28:27,980 the person behind and it's basically a domino 810 00:28:27,980 --> 00:28:30,640 effect where you then you're effectively creating, 811 00:28:31,974 --> 00:28:34,375 kind of a wave within the traffic itself 812 00:28:34,375 --> 00:28:35,674 of people just breaking 813 00:28:36,054 --> 00:28:37,595 and then accelerating off. 814 00:28:38,534 --> 00:28:40,534 So yeah, physicists have studied these kinds of 815 00:28:40,534 --> 00:28:43,095 waves and the physicists call these waves, 816 00:28:43,494 --> 00:28:43,994 jamitons. 817 00:28:44,950 --> 00:28:46,950 So basically, they just kind of happen happen 818 00:28:46,950 --> 00:28:48,870 for no reason. And that was kind of 819 00:28:48,870 --> 00:28:50,870 the theory about how, you know, waves could 820 00:28:50,870 --> 00:28:52,809 actually form. But there were these researchers, 821 00:28:53,350 --> 00:28:55,370 in Japan actually, who did an actual experiment. 822 00:28:56,390 --> 00:28:57,450 Basically, they got, 823 00:28:58,035 --> 00:29:00,215 a number of cars on a circular road, 824 00:29:00,835 --> 00:29:02,595 just kind of a few 100 clump a 825 00:29:02,595 --> 00:29:03,734 few 100 metres, 826 00:29:04,595 --> 00:29:05,414 in circumference. 827 00:29:05,875 --> 00:29:07,715 And they put all they told the drivers 828 00:29:07,715 --> 00:29:10,035 is said, look. Just drive along the circular 829 00:29:10,035 --> 00:29:12,339 road and just keep going round, you know, 830 00:29:12,339 --> 00:29:13,700 as many times as you want. Just keep 831 00:29:13,700 --> 00:29:14,200 going. 832 00:29:14,579 --> 00:29:16,279 And they actually discovered that 833 00:29:17,700 --> 00:29:20,259 traffic jams just occurred naturally. So, you know, 834 00:29:20,259 --> 00:29:21,720 people would just drive along, 835 00:29:22,819 --> 00:29:23,960 and then they just, 836 00:29:24,285 --> 00:29:26,285 Basically, they probably just, you know, they just, 837 00:29:26,285 --> 00:29:27,965 some kind of something caught their eye and 838 00:29:27,965 --> 00:29:29,884 they just became distracted. They then broke and 839 00:29:29,884 --> 00:29:32,285 then basically they saw this exact kind of 840 00:29:32,285 --> 00:29:33,825 jamaton wave form. 841 00:29:34,365 --> 00:29:36,924 Even during a very, such a simple experiment 842 00:29:36,924 --> 00:29:39,184 as that way, you have basically circular road 843 00:29:39,460 --> 00:29:41,000 and cars on it. 844 00:29:41,380 --> 00:29:43,460 So that was basically the idea that, you 845 00:29:43,460 --> 00:29:44,519 know, it doesn't take 846 00:29:45,380 --> 00:29:47,619 traffic, it doesn't take a car to break 847 00:29:47,619 --> 00:29:48,680 down or, 848 00:29:49,299 --> 00:29:51,240 road works or anything like that. But even 849 00:29:51,565 --> 00:29:53,244 on a road where there's kind of a 850 00:29:53,244 --> 00:29:54,924 number once you get a certain density of 851 00:29:54,924 --> 00:29:56,445 cars on the road, then you can get 852 00:29:56,445 --> 00:29:58,465 these, jamaton waves forming. 853 00:29:59,965 --> 00:30:01,664 And, you know, that's basically, 854 00:30:03,880 --> 00:30:05,440 you know, how these waves can actually form. 855 00:30:05,440 --> 00:30:07,679 And it's, it's quite interesting research, but there's 856 00:30:07,679 --> 00:30:09,839 also, like, a lot of different aspects about 857 00:30:09,839 --> 00:30:11,039 driving around the city, 858 00:30:11,919 --> 00:30:12,819 that are interesting. 859 00:30:13,440 --> 00:30:16,079 There's one one particular interesting point that's been, 860 00:30:16,240 --> 00:30:18,134 covered in the book where I talk about 861 00:30:18,214 --> 00:30:19,515 the physics of parking 862 00:30:19,974 --> 00:30:22,214 a car on a one I mean, it's 863 00:30:22,214 --> 00:30:23,595 on a one dimensional road, 864 00:30:24,295 --> 00:30:26,134 which is, you know, a classic your classic 865 00:30:26,134 --> 00:30:26,634 physicist, 866 00:30:27,654 --> 00:30:29,414 you know, taking a problem down to its 867 00:30:29,414 --> 00:30:30,075 bare minimum. 868 00:30:30,720 --> 00:30:32,160 But then they look at, you know, how 869 00:30:32,160 --> 00:30:34,160 how you what strategy you could come up 870 00:30:34,160 --> 00:30:36,319 against. Well, if you have a one, one 871 00:30:36,480 --> 00:30:38,400 basically a single road and you want to 872 00:30:38,400 --> 00:30:38,799 get, 873 00:30:39,599 --> 00:30:41,039 you want to park in the best spot 874 00:30:41,039 --> 00:30:42,640 to get to a destination at the end 875 00:30:42,640 --> 00:30:44,319 of the road, you know, what is a 876 00:30:44,319 --> 00:30:45,855 certain strategy to do that? 877 00:30:46,414 --> 00:30:48,994 So they looked at three possibilities. One was, 878 00:30:49,855 --> 00:30:52,654 the so called meek strategy, where you basically 879 00:30:52,654 --> 00:30:54,595 just go and park in the first spot, 880 00:30:55,134 --> 00:30:55,794 end of 881 00:30:56,174 --> 00:30:57,375 you know, but the issue with that is 882 00:30:57,375 --> 00:30:58,654 that you park in the first spot, but 883 00:30:58,654 --> 00:31:00,380 then you have to then walk to the 884 00:31:00,380 --> 00:31:02,079 destination. So that takes time. 885 00:31:03,019 --> 00:31:06,059 Another option was a prudent strategy where you 886 00:31:06,059 --> 00:31:07,519 ignore that first spot. 887 00:31:07,980 --> 00:31:10,159 You then see a group of cars, 888 00:31:10,460 --> 00:31:11,899 in front of you, and maybe there's a 889 00:31:11,899 --> 00:31:12,639 spot there. 890 00:31:13,095 --> 00:31:15,015 Then you go into that spot. That's called 891 00:31:15,015 --> 00:31:16,394 the so called prudent strategy. 892 00:31:17,095 --> 00:31:19,494 And then a third strategy was called an 893 00:31:19,494 --> 00:31:21,654 optimistic one, where you basically drive all the 894 00:31:21,654 --> 00:31:22,794 way down to the, 895 00:31:23,654 --> 00:31:24,554 end of the road, 896 00:31:25,069 --> 00:31:27,150 turn back on yourself, and then go in 897 00:31:27,150 --> 00:31:29,150 the first spot. So you kind of think, 898 00:31:29,150 --> 00:31:31,789 well, surely the optimistic strategy is the best 899 00:31:31,789 --> 00:31:34,269 because you basically get it's guaranteed that you're 900 00:31:34,269 --> 00:31:35,490 gonna get the best spot. 901 00:31:36,190 --> 00:31:38,349 But when the researchers run through the various 902 00:31:38,349 --> 00:31:39,490 simulations, etcetera, 903 00:31:40,035 --> 00:31:42,355 they actually discovered that the prudent strategy was 904 00:31:42,355 --> 00:31:43,494 a better one, 905 00:31:43,875 --> 00:31:45,555 because that got you in a spot that 906 00:31:45,555 --> 00:31:48,115 maybe not was is maybe up the furthest 907 00:31:48,115 --> 00:31:48,615 away, 908 00:31:49,075 --> 00:31:50,515 but it's some kind of, you know, nearer 909 00:31:50,515 --> 00:31:52,355 to the destination, then you can walk to 910 00:31:52,355 --> 00:31:52,710 it. 911 00:31:53,429 --> 00:31:56,329 And that actually has links with, the secretary 912 00:31:56,390 --> 00:31:57,849 problem in mathematics. 913 00:31:59,190 --> 00:32:00,490 But it's kind of the optimal, 914 00:32:01,349 --> 00:32:03,349 how many how much do you kind of 915 00:32:03,349 --> 00:32:04,970 ignore before you then, 916 00:32:05,669 --> 00:32:07,305 park? So, yeah, if you're ever on a, 917 00:32:07,705 --> 00:32:09,945 basically, if you're ever on a one dimensional 918 00:32:09,945 --> 00:32:12,505 street, then the optimal solution to it is 919 00:32:12,505 --> 00:32:14,365 to kind of ignore about half the spaces 920 00:32:14,585 --> 00:32:16,025 and then park in the next in the 921 00:32:16,025 --> 00:32:17,945 next one. Right. Then you've kind of got 922 00:32:17,945 --> 00:32:20,345 about a 25 to 30% chance that you'll 923 00:32:20,345 --> 00:32:21,660 actually end in the 924 00:32:22,299 --> 00:32:23,440 best spot possible. 925 00:32:23,820 --> 00:32:26,220 Gotcha. Yeah. And now I'm trying to imagine 926 00:32:26,220 --> 00:32:27,740 how to make a u-turn on a one 927 00:32:27,740 --> 00:32:30,220 dimensional road, but I'm guessing that they don't, 928 00:32:30,460 --> 00:32:32,539 they don't they probably reverse bike, all the 929 00:32:32,539 --> 00:32:33,039 way. 930 00:32:35,575 --> 00:32:37,735 And then you've also looked at, 931 00:32:38,295 --> 00:32:40,634 at other modes of of transportation. 932 00:32:40,934 --> 00:32:43,255 And, you you know, you've got that classic 933 00:32:43,255 --> 00:32:45,434 thing, the boarding of aircraft, 934 00:32:46,215 --> 00:32:47,115 which I think, 935 00:32:47,654 --> 00:32:49,494 you know, I've been I I suppose I've 936 00:32:49,494 --> 00:32:49,994 been 937 00:32:50,600 --> 00:32:53,160 I I've I've flown on aircraft for the 938 00:32:53,160 --> 00:32:55,799 last, I don't know, four forty five years. 939 00:32:55,799 --> 00:32:56,359 And I think, 940 00:32:57,960 --> 00:33:00,940 you know, definitely the strategies that the airlines 941 00:33:01,080 --> 00:33:03,559 take have changed over the ages, and maybe 942 00:33:03,559 --> 00:33:05,340 they've refined them. Or, 943 00:33:06,825 --> 00:33:07,724 and and 944 00:33:08,265 --> 00:33:09,545 so you have a look at the at 945 00:33:09,545 --> 00:33:12,025 the various different strategies. And then there is 946 00:33:12,025 --> 00:33:14,025 a twist in the tale, isn't there? There's 947 00:33:14,025 --> 00:33:14,684 a surprise, 948 00:33:15,785 --> 00:33:17,005 at the end about, 949 00:33:18,419 --> 00:33:20,339 a technique that you might as well use 950 00:33:20,339 --> 00:33:23,000 because it's it's almost as good as, 951 00:33:24,059 --> 00:33:27,059 as the actual best technique for boarding an 952 00:33:27,059 --> 00:33:29,079 aircraft. So what what what have people 953 00:33:29,539 --> 00:33:32,099 found when they've looked done research into, 954 00:33:32,500 --> 00:33:33,720 into boarding aircraft? 955 00:33:34,384 --> 00:33:35,984 Yeah. I think they can the basically the 956 00:33:35,984 --> 00:33:36,944 bottom line is, 957 00:33:37,505 --> 00:33:39,505 the kind of the current method of boarding 958 00:33:39,505 --> 00:33:40,164 an aircraft, 959 00:33:40,625 --> 00:33:42,544 you know, usually it's kind of back to 960 00:33:42,544 --> 00:33:44,464 front boarding where you get all the people 961 00:33:44,464 --> 00:33:46,644 on the back and then they altogether 962 00:33:47,410 --> 00:33:49,329 unload, and then you get the next next 963 00:33:49,329 --> 00:33:51,009 batch in. So you, you know, you board 964 00:33:51,009 --> 00:33:52,049 it all the way to the front. 965 00:33:52,609 --> 00:33:54,930 That kind of in terms of the speed 966 00:33:54,930 --> 00:33:57,109 of boarding isn't the kind of ideal, 967 00:33:58,289 --> 00:33:59,990 way. Actually, one one 968 00:34:00,595 --> 00:34:03,095 possibility that is actually quite quick is actually 969 00:34:03,394 --> 00:34:05,315 one that you might not think, which is 970 00:34:05,315 --> 00:34:07,954 basically random. That's right. Where you basically just 971 00:34:07,954 --> 00:34:08,454 randomise 972 00:34:08,835 --> 00:34:11,974 people boarding and that actually in the simulations, 973 00:34:12,514 --> 00:34:14,355 that people have carried out, that actually is, 974 00:34:15,519 --> 00:34:16,019 quicker 975 00:34:16,720 --> 00:34:17,599 than the current, 976 00:34:18,480 --> 00:34:20,160 than the current method. But there is a 977 00:34:20,160 --> 00:34:21,940 there is a one that a researcher, 978 00:34:22,640 --> 00:34:23,920 came came up with, 979 00:34:24,320 --> 00:34:25,380 which was, 980 00:34:27,039 --> 00:34:29,119 the kind of the best tech best technique. 981 00:34:29,119 --> 00:34:30,734 And that's kind of like splitting up the 982 00:34:30,734 --> 00:34:32,255 roles itself. So you would, you know, you 983 00:34:32,255 --> 00:34:34,894 go in one one, say 12, and but 984 00:34:34,894 --> 00:34:37,375 then you don't board the next row 11, 985 00:34:37,375 --> 00:34:39,074 you kind of skip skip one. 986 00:34:39,934 --> 00:34:41,635 So it's a bit more kind of involved 987 00:34:41,775 --> 00:34:42,514 than the 988 00:34:43,135 --> 00:34:44,994 the way that airlines do at the moment. 989 00:34:45,140 --> 00:34:47,400 But that was actually found to be the 990 00:34:47,780 --> 00:34:50,420 quickest way. And they actually the researchers themselves 991 00:34:50,420 --> 00:34:53,140 actually carried out an experiment where they got 992 00:34:53,140 --> 00:34:53,880 a mock 993 00:34:54,579 --> 00:34:56,119 aircraft, an actual 994 00:34:56,420 --> 00:34:59,699 life-sized mock aircraft, and they tested out all 995 00:34:59,699 --> 00:35:00,760 these various strategies, 996 00:35:01,994 --> 00:35:04,494 including the, completely random one. 997 00:35:05,194 --> 00:35:07,194 And then they discovered that basically, you know, 998 00:35:07,194 --> 00:35:07,674 this, 999 00:35:08,554 --> 00:35:11,034 this way of kind of splitting up roles, 1000 00:35:11,034 --> 00:35:11,855 you know, 10, 1001 00:35:12,554 --> 00:35:15,054 to what say, row twelve, ten, eight, 1002 00:35:15,789 --> 00:35:16,529 was actually 1003 00:35:16,829 --> 00:35:17,650 quick. But, 1004 00:35:18,429 --> 00:35:21,069 it seems like airlines actually are beginning to 1005 00:35:21,069 --> 00:35:22,349 look at the, 1006 00:35:22,909 --> 00:35:25,230 the procedures for for doing that. I think 1007 00:35:25,230 --> 00:35:26,049 there was something 1008 00:35:26,429 --> 00:35:27,730 about United Airlines, 1009 00:35:28,190 --> 00:35:29,257 in October 1010 00:35:29,257 --> 00:35:30,164 2023. 1011 00:35:30,644 --> 00:35:32,565 So they they they announced that they would 1012 00:35:32,565 --> 00:35:33,304 start boarding, 1013 00:35:34,724 --> 00:35:38,344 economy class passengers on, this method called Wilmer, 1014 00:35:39,204 --> 00:35:40,485 which is kind of a way of just, 1015 00:35:40,485 --> 00:35:42,804 you know, splitting up people in different in 1016 00:35:42,804 --> 00:35:43,545 different roles. 1017 00:35:44,660 --> 00:35:46,579 So, yeah, maybe, you know, maybe in future, 1018 00:35:46,579 --> 00:35:47,860 we won't be boarding just from the back 1019 00:35:47,860 --> 00:35:49,460 to the front, but we'll actually be using 1020 00:35:49,460 --> 00:35:51,539 these different different ways of boarding. You know, 1021 00:35:51,539 --> 00:35:52,500 because I guess, you know, at the end 1022 00:35:52,500 --> 00:35:53,700 of the day, you know, time is money, 1023 00:35:53,700 --> 00:35:55,220 isn't it? You know? So if you can 1024 00:35:55,220 --> 00:35:57,059 get people onto an aircraft quicker, you can 1025 00:35:57,059 --> 00:35:58,500 get away quicker, you know? So it does 1026 00:35:58,500 --> 00:35:58,934 have 1027 00:35:59,494 --> 00:36:02,295 financial implications. So you would think that airlines 1028 00:36:02,295 --> 00:36:04,394 would be more interested in, 1029 00:36:04,775 --> 00:36:06,954 you know, changing those boarding methods. 1030 00:36:07,255 --> 00:36:09,494 I mean, the interesting thing about when you 1031 00:36:09,494 --> 00:36:11,355 compare the, let's say, the Wilma 1032 00:36:11,719 --> 00:36:12,619 to the random, 1033 00:36:13,319 --> 00:36:14,059 is that 1034 00:36:14,519 --> 00:36:16,519 I mean, is there really a big difference 1035 00:36:16,519 --> 00:36:18,599 between those two strategies? Because when you think 1036 00:36:18,599 --> 00:36:20,619 about it, if you're doing it randomly, 1037 00:36:21,400 --> 00:36:23,319 if it is random, then if I get 1038 00:36:23,319 --> 00:36:25,614 on the plane, chances are the person in 1039 00:36:25,614 --> 00:36:28,434 front of me and the person behind me 1040 00:36:28,734 --> 00:36:29,714 are going to be 1041 00:36:30,014 --> 00:36:32,894 separated from me on the plane. So we'll 1042 00:36:32,894 --> 00:36:35,775 all have enough space to pack our stuff 1043 00:36:35,775 --> 00:36:36,914 away and quickly 1044 00:36:37,539 --> 00:36:40,260 get into our seats. So is I mean, 1045 00:36:40,260 --> 00:36:42,659 is there is there really any benefit between 1046 00:36:42,659 --> 00:36:44,739 Wilma and the random? Because I think I 1047 00:36:44,739 --> 00:36:46,279 think in the book, you say that 1048 00:36:46,659 --> 00:36:49,059 random is almost as Is it almost as 1049 00:36:49,059 --> 00:36:49,836 good as Wilma? That's right. It's almost as 1050 00:36:49,836 --> 00:36:50,599 effective. Yeah. That's right. 1051 00:36:52,224 --> 00:36:53,764 You would think in that sense 1052 00:36:54,224 --> 00:36:56,164 that it probably is better just to go 1053 00:36:56,224 --> 00:36:57,984 just to go random. Yeah. Because, I mean, 1054 00:36:57,984 --> 00:36:59,284 Wilma seems very 1055 00:36:59,664 --> 00:37:01,505 complicated and, you know, how you you know 1056 00:37:01,505 --> 00:37:03,125 what it's like. I mean, I just flew 1057 00:37:03,264 --> 00:37:05,505 back from Toronto and, you know, you always 1058 00:37:05,505 --> 00:37:07,859 get the situation where, you know, people who 1059 00:37:07,859 --> 00:37:09,400 are last to board 1060 00:37:10,500 --> 00:37:12,119 stand at the front of the queue 1061 00:37:12,659 --> 00:37:16,039 and basically block everybody else from getting on, 1062 00:37:16,819 --> 00:37:19,219 you know, which is very annoying. Actually, once, 1063 00:37:19,219 --> 00:37:20,659 I I took a flight. It was from 1064 00:37:20,659 --> 00:37:22,744 Toronto as well. And, 1065 00:37:23,284 --> 00:37:26,005 one of the gate staff actually stood there 1066 00:37:26,005 --> 00:37:27,625 and berated people 1067 00:37:28,005 --> 00:37:29,924 and said, you, what what group are you 1068 00:37:29,924 --> 00:37:31,684 in? Five. Oh, no. No. No. This is 1069 00:37:31,684 --> 00:37:34,005 three. Get out of here. Right? You know, 1070 00:37:34,005 --> 00:37:36,500 I was thinking, this is great. You know? 1071 00:37:36,719 --> 00:37:37,219 Unfortunately, 1072 00:37:37,519 --> 00:37:39,440 the the last flight, they they didn't have 1073 00:37:39,440 --> 00:37:40,579 somebody doing that. 1074 00:37:41,039 --> 00:37:41,440 But, 1075 00:37:42,000 --> 00:37:43,920 but, yeah, that is and, you know, it 1076 00:37:43,920 --> 00:37:45,679 is interesting because when I tell people, I 1077 00:37:45,679 --> 00:37:47,460 say, well, you know, physics says 1078 00:37:48,005 --> 00:37:51,125 that random boarding is is actually a pretty 1079 00:37:51,125 --> 00:37:53,545 good way of doing it. Nobody believes you. 1080 00:37:53,765 --> 00:37:54,164 But, 1081 00:37:54,724 --> 00:37:56,644 I mean, I I I don't know if 1082 00:37:56,644 --> 00:37:59,045 it's maybe it's because I'm a physicist. I 1083 00:37:59,045 --> 00:38:01,065 have a I sort of have a great, 1084 00:38:02,109 --> 00:38:04,030 you know, I think randomness can be very 1085 00:38:04,030 --> 00:38:07,389 useful. I mean, a classic one, is stuffing 1086 00:38:07,389 --> 00:38:08,530 a sleeping bag 1087 00:38:08,909 --> 00:38:11,550 into a sack. Right? Now you'd be very 1088 00:38:11,550 --> 00:38:13,949 tempted to think the the most efficient way 1089 00:38:13,949 --> 00:38:16,075 to do that is to roll up the 1090 00:38:16,075 --> 00:38:18,795 sleeping bag. But the problem with rolling it 1091 00:38:18,795 --> 00:38:20,335 up is that you're introducing 1092 00:38:21,114 --> 00:38:21,775 a preferred 1093 00:38:22,155 --> 00:38:22,655 direction. 1094 00:38:23,355 --> 00:38:25,675 Right? And if you don't get the the 1095 00:38:25,675 --> 00:38:27,695 length of that roll correct, 1096 00:38:28,309 --> 00:38:29,510 it you're gonna have a hell of a 1097 00:38:29,510 --> 00:38:31,989 time getting it into the sack. Whereas if 1098 00:38:31,989 --> 00:38:33,369 you just stuff it in, 1099 00:38:34,710 --> 00:38:37,030 it's random. And, you know, the sleeping bag 1100 00:38:37,030 --> 00:38:39,590 can randomly fill the space. It's a bit 1101 00:38:39,590 --> 00:38:41,130 like a glass, right, 1102 00:38:41,429 --> 00:38:42,090 I suppose. 1103 00:38:43,394 --> 00:38:45,094 Anyway, that's how I think of it. 1104 00:38:45,394 --> 00:38:47,235 But, yeah, maybe it's one of those perfect 1105 00:38:47,235 --> 00:38:49,155 things where randomness is. Because you wouldn't It's 1106 00:38:49,155 --> 00:38:51,074 your friend. You wouldn't exactly. You would not 1107 00:38:51,074 --> 00:38:52,375 expect a random 1108 00:38:52,994 --> 00:38:55,089 boarding process to be. You'd think it'd be 1109 00:38:55,089 --> 00:38:57,010 chaotic. You just need to be absolutely not. 1110 00:38:57,010 --> 00:38:59,089 But, yeah, you know, the experiments say otherwise, 1111 00:38:59,089 --> 00:39:00,449 and it is actually one of the best 1112 00:39:00,449 --> 00:39:01,489 ways to do it. So 1113 00:39:02,609 --> 00:39:04,769 And the the the there's a few you 1114 00:39:04,769 --> 00:39:06,230 you you talk about health, 1115 00:39:06,849 --> 00:39:07,969 in your book. And, 1116 00:39:09,295 --> 00:39:11,054 it's interesting that a lot of the the 1117 00:39:11,054 --> 00:39:12,974 things that you mentioned were were things that 1118 00:39:12,974 --> 00:39:14,434 came up during the COVID 1119 00:39:14,894 --> 00:39:15,394 nineteen 1120 00:39:15,855 --> 00:39:18,914 pandemic, where we were obviously very, very, very 1121 00:39:19,054 --> 00:39:20,894 concerned about the spread of, 1122 00:39:21,454 --> 00:39:22,355 virus particles. 1123 00:39:23,819 --> 00:39:25,579 And the the the one thing that you 1124 00:39:25,579 --> 00:39:27,339 looked at, and, you know, I have to 1125 00:39:27,339 --> 00:39:29,819 say it's made me think of toilets in 1126 00:39:29,819 --> 00:39:33,259 a different way ever since, is how toilets 1127 00:39:33,259 --> 00:39:35,039 are actually very good at 1128 00:39:35,534 --> 00:39:36,674 spreading aerosol 1129 00:39:36,974 --> 00:39:39,694 particles. So what what what exactly happens there? 1130 00:39:39,694 --> 00:39:41,534 This is when you flush the toilet, I 1131 00:39:41,534 --> 00:39:43,295 assume. That's right. Yeah. So it's when you 1132 00:39:43,295 --> 00:39:45,375 when you flush the toilet. And and, yeah, 1133 00:39:45,375 --> 00:39:47,454 this research was one of those ones that 1134 00:39:47,454 --> 00:39:50,139 basically came out purely from the COVID, 1135 00:39:50,780 --> 00:39:52,480 pan you know, pandemic where, 1136 00:39:53,980 --> 00:39:54,880 some researchers 1137 00:39:55,179 --> 00:39:58,219 researchers contacted this, a researcher in The US 1138 00:39:58,219 --> 00:40:00,880 who was an expert in kind of imaging, 1139 00:40:02,860 --> 00:40:03,360 aerosols 1140 00:40:03,739 --> 00:40:05,519 and, you know, the spread of aerosols. 1141 00:40:06,324 --> 00:40:07,925 And they were interested in, you know, looking 1142 00:40:07,925 --> 00:40:10,565 at the aerosol that's created when you flush 1143 00:40:10,565 --> 00:40:11,144 a toilet. 1144 00:40:12,244 --> 00:40:14,005 So there had been before then, there had 1145 00:40:14,005 --> 00:40:15,844 been some theoretical work done, 1146 00:40:16,324 --> 00:40:18,164 which showed that when you basically flush a 1147 00:40:18,164 --> 00:40:20,250 toilet, you know, the the water pours in. 1148 00:40:20,250 --> 00:40:21,070 It's quite energetic 1149 00:40:21,610 --> 00:40:24,590 process, and it flows into the cistern. 1150 00:40:25,289 --> 00:40:27,210 And then it can basically create like a 1151 00:40:27,210 --> 00:40:28,110 jet where, 1152 00:40:28,730 --> 00:40:30,590 it can basically just fling 1153 00:40:30,969 --> 00:40:33,074 particles out of this chaotic 1154 00:40:33,614 --> 00:40:34,114 vortex 1155 00:40:34,494 --> 00:40:36,655 like jet in the toilet in the toilet 1156 00:40:36,655 --> 00:40:37,155 bowl. 1157 00:40:37,934 --> 00:40:39,375 But that was all of that just kind 1158 00:40:39,375 --> 00:40:42,114 of, theoretical work. So these researchers, 1159 00:40:43,055 --> 00:40:45,150 were really wanting to find out whether this 1160 00:40:45,150 --> 00:40:47,389 is the case in terms of doing actual 1161 00:40:47,389 --> 00:40:48,530 experiments. So they, 1162 00:40:49,389 --> 00:40:51,550 basically filmed this toilet set up, 1163 00:40:52,030 --> 00:40:53,389 when they have all this kind of green 1164 00:40:53,389 --> 00:40:55,329 laser light around, so they could basically 1165 00:40:55,630 --> 00:40:58,589 visualise the plume that's created without actually disturbing 1166 00:40:58,589 --> 00:41:00,925 it. It's quite important that you don't 1167 00:41:01,385 --> 00:41:03,804 disturb the plume itself when you're actually 1168 00:41:04,105 --> 00:41:05,005 looking at it. 1169 00:41:05,465 --> 00:41:07,724 And what they found, you know, they told 1170 00:41:08,505 --> 00:41:09,465 me, you know, wrote about it in the 1171 00:41:09,465 --> 00:41:12,125 book, you know, really startled them, 1172 00:41:12,505 --> 00:41:14,460 that they literally found this kind of 1173 00:41:15,179 --> 00:41:16,880 these particles just shooting out, 1174 00:41:17,339 --> 00:41:19,179 like a rocket, basically, where you know, and 1175 00:41:19,179 --> 00:41:21,420 they were going basically about a couple of 1176 00:41:21,420 --> 00:41:22,239 meters high. 1177 00:41:23,339 --> 00:41:25,260 Where presumably you could breathe them in. Well, 1178 00:41:25,260 --> 00:41:25,660 exactly. 1179 00:41:26,059 --> 00:41:26,559 Contained 1180 00:41:27,179 --> 00:41:27,659 COVID, 1181 00:41:28,114 --> 00:41:31,014 COVID nineteen virus particles or some other nasty 1182 00:41:31,234 --> 00:41:33,574 Exactly. Basically, head height for most people, 1183 00:41:34,114 --> 00:41:36,135 they they could actually reach. 1184 00:41:37,795 --> 00:41:39,875 So, yeah, basically, by the process of flushing 1185 00:41:39,875 --> 00:41:42,380 itself is so you know, energetic that it 1186 00:41:42,380 --> 00:41:44,219 can create it can throw particles out, but 1187 00:41:44,219 --> 00:41:46,480 it also can create this kind of aerosol, 1188 00:41:46,539 --> 00:41:47,039 basically. 1189 00:41:48,460 --> 00:41:49,820 You know, a bunch of particles that then 1190 00:41:49,820 --> 00:41:51,420 can kind of spread around as well because 1191 00:41:51,420 --> 00:41:53,200 they kind of move around in the air. 1192 00:41:53,739 --> 00:41:56,219 So that's actually another another piece of work 1193 00:41:56,219 --> 00:41:57,315 as well looked at, 1194 00:41:58,514 --> 00:42:01,394 you know, where this aerosol could could kind 1195 00:42:01,394 --> 00:42:02,775 of how far it could travel. 1196 00:42:03,795 --> 00:42:06,034 And they seeded the toilet itself actually with 1197 00:42:06,034 --> 00:42:07,815 kind of bacteria, e coli, etcetera. 1198 00:42:08,835 --> 00:42:10,514 And then they flushed the toilet, and then 1199 00:42:10,514 --> 00:42:11,494 they took swabs, 1200 00:42:12,159 --> 00:42:13,380 swabs around the room. 1201 00:42:13,840 --> 00:42:16,000 So they kind of took samples around and 1202 00:42:16,000 --> 00:42:18,400 they found basically that the, that the process 1203 00:42:18,400 --> 00:42:20,659 of flushing an open toilet just basically 1204 00:42:20,960 --> 00:42:23,539 put, you know, put stuff e coli everywhere, 1205 00:42:23,760 --> 00:42:25,440 basically around is on the walls, on the 1206 00:42:25,440 --> 00:42:26,820 ceiling, it was on the floors. 1207 00:42:27,795 --> 00:42:29,394 So you might think because the result's that, 1208 00:42:29,394 --> 00:42:31,474 you might think, well, that's obvious. You just 1209 00:42:31,474 --> 00:42:33,394 close the lid. That's an obvious solution. You 1210 00:42:33,394 --> 00:42:35,474 know? What what could go wrong? But when 1211 00:42:35,474 --> 00:42:37,714 they actually then decided to do that and 1212 00:42:37,714 --> 00:42:39,974 did the experiments, they actually found that, 1213 00:42:40,690 --> 00:42:42,550 you know, it didn't help at all. Basically 1214 00:42:42,610 --> 00:42:44,690 more material was put on the floor, but 1215 00:42:44,690 --> 00:42:45,590 it even reached 1216 00:42:46,050 --> 00:42:48,230 the walls and the ceiling itself. 1217 00:42:49,329 --> 00:42:50,869 So basically there is no, 1218 00:42:51,969 --> 00:42:54,309 there's no real way to get around that 1219 00:42:54,394 --> 00:42:56,635 except, you know, of course, from disinfecting your 1220 00:42:56,635 --> 00:42:58,335 toilet quite quite often. 1221 00:42:58,714 --> 00:43:00,394 It's probably the best way of getting around 1222 00:43:00,394 --> 00:43:00,894 it. 1223 00:43:01,594 --> 00:43:03,275 But the researcher who did that way, you 1224 00:43:03,275 --> 00:43:04,074 know, they said, 1225 00:43:04,554 --> 00:43:06,155 they gave me a funny quote where they 1226 00:43:06,155 --> 00:43:08,860 basically said that after they did that research, 1227 00:43:08,860 --> 00:43:10,699 you know, they basically flush the toilet and 1228 00:43:10,699 --> 00:43:11,199 run. 1229 00:43:11,739 --> 00:43:12,239 That's 1230 00:43:12,699 --> 00:43:14,539 and also a bit and also to not 1231 00:43:14,539 --> 00:43:16,460 put your toothbrush anywhere near, 1232 00:43:16,940 --> 00:43:19,019 the toilet because basically, you know, that aerosol 1233 00:43:19,019 --> 00:43:20,835 is basically just going all over it. But 1234 00:43:21,155 --> 00:43:21,655 Right. 1235 00:43:22,675 --> 00:43:24,994 On that note, let let let's move on 1236 00:43:24,994 --> 00:43:27,554 to something much more cheery, and that's the 1237 00:43:27,554 --> 00:43:28,855 physics of champagne. 1238 00:43:29,875 --> 00:43:30,195 And, 1239 00:43:30,755 --> 00:43:32,835 one little tidbit. I mean, I suppose I 1240 00:43:32,835 --> 00:43:34,855 should have known this is is the incredible 1241 00:43:34,994 --> 00:43:35,494 pressure 1242 00:43:36,239 --> 00:43:38,099 that, champagne is under 1243 00:43:38,559 --> 00:43:39,039 when, 1244 00:43:39,760 --> 00:43:42,079 inside a bottle. It's what was it twice 1245 00:43:42,079 --> 00:43:44,400 the the pressure of a a car tire? 1246 00:43:44,400 --> 00:43:46,800 Yeah. Something like that. Car tire is around 1247 00:43:46,800 --> 00:43:47,300 two 1248 00:43:47,599 --> 00:43:50,179 bar. And, yeah, the pressure in a champagne 1249 00:43:50,400 --> 00:43:52,855 so the in the neck of the champagne 1250 00:43:52,855 --> 00:43:54,934 bottle can be around, yeah, around five bar 1251 00:43:54,934 --> 00:43:55,815 or so. So quite 1252 00:43:56,614 --> 00:43:58,214 and, of course, the pressure increases with the 1253 00:43:58,214 --> 00:43:59,815 temperature. So you have a chilled bottle and 1254 00:43:59,815 --> 00:44:01,414 the temperature's a bit lower, but it's a 1255 00:44:01,414 --> 00:44:03,519 warmer bottle and it's a bit higher. So 1256 00:44:03,519 --> 00:44:04,500 it can be quite, 1257 00:44:05,119 --> 00:44:07,840 actually, yeah, opening a champagne bottle can be 1258 00:44:07,840 --> 00:44:09,680 quite a lethal process because, you know, if 1259 00:44:09,680 --> 00:44:11,519 you've got all that pressure just in that 1260 00:44:11,519 --> 00:44:12,019 headspace, 1261 00:44:12,640 --> 00:44:14,480 and then it'll, you know, impact on the 1262 00:44:14,480 --> 00:44:16,180 cork, and the cork can and actually, 1263 00:44:16,559 --> 00:44:18,545 during holiday season, holiday periods, and you have 1264 00:44:18,545 --> 00:44:19,605 a lot of injuries, 1265 00:44:20,305 --> 00:44:21,744 where people, you know, hit cork. Cork to 1266 00:44:21,744 --> 00:44:23,744 the eye. Conte. Exactly. A cork to the 1267 00:44:23,744 --> 00:44:25,425 eye. Yeah. Yeah. Which you can can be 1268 00:44:25,425 --> 00:44:27,265 actually very dangerous. It's, you know, it's a 1269 00:44:27,265 --> 00:44:27,925 lot of, 1270 00:44:29,025 --> 00:44:30,385 you know, it's a lot of pressure that's 1271 00:44:30,385 --> 00:44:32,869 kind of, you know, producing that high speed 1272 00:44:32,869 --> 00:44:34,950 cork. Yeah. Yeah. I'm sure if it went 1273 00:44:34,950 --> 00:44:36,550 in the wrong direction, it could, you know, 1274 00:44:36,550 --> 00:44:37,930 smash a window or 1275 00:44:38,309 --> 00:44:40,410 take take out your your your favorite, 1276 00:44:40,789 --> 00:44:41,289 knickknack, 1277 00:44:43,030 --> 00:44:44,090 over the fireplace. 1278 00:44:45,094 --> 00:44:45,755 And and 1279 00:44:46,135 --> 00:44:47,194 one thing that you 1280 00:44:47,815 --> 00:44:50,375 you talk about is the that sound of 1281 00:44:50,375 --> 00:44:51,994 the pop, that characteristic 1282 00:44:52,454 --> 00:44:53,275 pop. And 1283 00:44:53,894 --> 00:44:55,655 am I writing in thinking it's a bit 1284 00:44:55,655 --> 00:44:57,894 like the a sonic boom, or maybe it 1285 00:44:57,894 --> 00:45:00,289 is a sonic boom? Yeah. That's right. So, 1286 00:45:00,769 --> 00:45:02,949 when you open a bottle of champagne, 1287 00:45:04,289 --> 00:45:06,389 basically, it's the the pressure, 1288 00:45:07,010 --> 00:45:08,150 drop that happens. 1289 00:45:08,690 --> 00:45:10,289 Basically, I have a huge kind of temperature 1290 00:45:10,289 --> 00:45:13,244 drop that happens when the champagne opens itself, 1291 00:45:14,204 --> 00:45:14,704 opens. 1292 00:45:16,045 --> 00:45:17,885 And then basically what can happen though is 1293 00:45:17,885 --> 00:45:19,885 you have the creation of, like, these MAC 1294 00:45:19,885 --> 00:45:20,385 discs 1295 00:45:20,765 --> 00:45:23,244 in the due to this huge temperature pressure 1296 00:45:23,244 --> 00:45:23,744 drop. 1297 00:45:24,365 --> 00:45:26,445 In temperature up, you have this, creation of 1298 00:45:26,445 --> 00:45:27,869 MAC discs. So, basically, 1299 00:45:28,170 --> 00:45:30,969 each time you are opening a champagne bottle, 1300 00:45:30,969 --> 00:45:32,429 you are actually kind of breaking 1301 00:45:32,730 --> 00:45:34,409 the soundbar in some sense by, you know, 1302 00:45:34,409 --> 00:45:36,570 the creation of these. It tends to be 1303 00:45:36,570 --> 00:45:38,570 just a single MAC disc up produced and 1304 00:45:38,570 --> 00:45:40,329 then basically kind of then kind of moves 1305 00:45:40,329 --> 00:45:40,829 up 1306 00:45:41,684 --> 00:45:43,684 into high you know, people have done various 1307 00:45:43,684 --> 00:45:45,605 high speed imagery on it. Moves up and 1308 00:45:45,605 --> 00:45:47,045 then it kind of moves back down into 1309 00:45:47,045 --> 00:45:48,505 the into the bottle itself. 1310 00:45:49,204 --> 00:45:51,045 But there's been various yeah. Lots of kind 1311 00:45:51,045 --> 00:45:53,684 of experimental work and actually theoretical work on 1312 00:45:53,684 --> 00:45:55,789 it as well where, you know, people, 1313 00:45:56,809 --> 00:45:58,250 have calculated that. You should actually be able 1314 00:45:58,250 --> 00:45:59,690 to see a few Mach disks created. It's 1315 00:45:59,690 --> 00:46:00,670 not just one. 1316 00:46:01,369 --> 00:46:02,989 Similar to what you see in a jet 1317 00:46:03,050 --> 00:46:04,969 fighter plane, where you see the creation of, 1318 00:46:05,210 --> 00:46:07,450 Mach disks and then Mach diamonds as well 1319 00:46:07,450 --> 00:46:08,744 in the exhaust plume. 1320 00:46:09,704 --> 00:46:11,385 A similar thing is kind of via the 1321 00:46:11,385 --> 00:46:12,905 physics of it. It's very similar to what's 1322 00:46:12,905 --> 00:46:14,825 happening when you open a bottle of champagne. 1323 00:46:14,825 --> 00:46:15,565 We have the 1324 00:46:15,865 --> 00:46:17,704 creation of these Mach disks due to that, 1325 00:46:17,704 --> 00:46:18,525 you know, incredible 1326 00:46:18,825 --> 00:46:20,445 kind of pressure drop that happens. 1327 00:46:21,305 --> 00:46:23,144 And the the other thing you look at 1328 00:46:23,144 --> 00:46:23,644 is, 1329 00:46:24,969 --> 00:46:25,469 bubbles 1330 00:46:26,489 --> 00:46:26,989 and 1331 00:46:27,369 --> 00:46:30,269 the bubbles that, champagne is famous for. 1332 00:46:30,570 --> 00:46:32,809 And the the thing that that sort of 1333 00:46:32,809 --> 00:46:35,070 fascinates me about beverage bubbles 1334 00:46:35,369 --> 00:46:37,650 is that they can vary. You know, a 1335 00:46:37,650 --> 00:46:39,550 a a champagne will have these tiny 1336 00:46:40,164 --> 00:46:40,664 bubbles. 1337 00:46:41,204 --> 00:46:42,664 And, I don't know, 1338 00:46:43,125 --> 00:46:44,964 probably get in trouble for saying this, but, 1339 00:46:44,964 --> 00:46:48,344 you know, a a lesser wine like, Prosecco, 1340 00:46:49,444 --> 00:46:50,964 you know, the bubbles will be a bit 1341 00:46:50,964 --> 00:46:51,464 bigger. 1342 00:46:52,085 --> 00:46:53,605 And by the time you get to a 1343 00:46:53,605 --> 00:46:54,420 fizzy drink, 1344 00:46:55,059 --> 00:46:56,039 you know, like, 1345 00:46:56,420 --> 00:46:58,659 Coca Cola or something, the the bubbles are 1346 00:46:58,659 --> 00:46:59,159 huge. 1347 00:46:59,699 --> 00:47:01,460 And, you you know, you think, well, this 1348 00:47:01,460 --> 00:47:02,920 is just liquid with 1349 00:47:03,940 --> 00:47:04,920 carbon dioxide. 1350 00:47:05,859 --> 00:47:07,079 Why are the bubbles 1351 00:47:07,784 --> 00:47:09,944 so different in size? And, you know, why 1352 00:47:09,944 --> 00:47:13,385 do we associate a high quality beverage with 1353 00:47:13,385 --> 00:47:14,204 small bubbles 1354 00:47:14,744 --> 00:47:18,204 and, you know, pop with with large bubbles? 1355 00:47:19,065 --> 00:47:21,724 That's something that's always fascinated me about 1356 00:47:22,050 --> 00:47:23,510 about carbonated drinks. 1357 00:47:24,369 --> 00:47:26,210 Yeah. Because with champagne, for example, it tends 1358 00:47:26,210 --> 00:47:27,570 to be, you know, a sign of the 1359 00:47:27,570 --> 00:47:29,650 quality. It's kind of the little kind of 1360 00:47:29,650 --> 00:47:31,090 bubbles that you kind of feel on your 1361 00:47:31,090 --> 00:47:32,690 mouth or your tongue when you're kind of, 1362 00:47:32,690 --> 00:47:34,469 you know, when you're drinking it. 1363 00:47:35,454 --> 00:47:37,214 But one one interesting thing about the the 1364 00:47:37,214 --> 00:47:39,375 bubbles that's create that you that you see 1365 00:47:39,375 --> 00:47:41,295 in champagne as compared to, as you say, 1366 00:47:41,295 --> 00:47:42,914 different beverages like 1367 00:47:43,295 --> 00:47:44,914 beer or Coke, for example. 1368 00:47:46,255 --> 00:47:48,414 One interesting effect with champagne is you get 1369 00:47:48,414 --> 00:47:49,714 these kind of bubble trains. 1370 00:47:50,130 --> 00:47:51,269 So you get literally 1371 00:47:51,969 --> 00:47:54,069 lines of bubbles, whereas in, 1372 00:47:54,769 --> 00:47:56,369 Coke, for example, you'll get them kind of 1373 00:47:56,369 --> 00:47:58,529 moving around. You know, they'll just be wavering 1374 00:47:58,529 --> 00:47:59,750 your own to the top. 1375 00:48:01,170 --> 00:48:03,489 So, yeah, you know, people have done research 1376 00:48:03,489 --> 00:48:04,789 about what why 1377 00:48:05,514 --> 00:48:08,014 does champagne have these bubble trains and other 1378 00:48:08,234 --> 00:48:09,215 drinks don't. 1379 00:48:09,755 --> 00:48:10,894 And that actually 1380 00:48:11,434 --> 00:48:12,574 all comes down to, 1381 00:48:14,074 --> 00:48:16,155 the kind of molecular makeup of the champagne 1382 00:48:16,155 --> 00:48:17,534 itself, and it kind of contains, 1383 00:48:18,869 --> 00:48:20,569 surfactants in the champagne. 1384 00:48:21,829 --> 00:48:24,569 And people have done various experiments where they've 1385 00:48:24,630 --> 00:48:27,190 kind of produced bubbles, and then they've kind 1386 00:48:27,190 --> 00:48:30,074 of adjusted the amount of surfactant in the 1387 00:48:30,394 --> 00:48:31,534 in the drink itself. 1388 00:48:32,474 --> 00:48:33,454 And, basically, 1389 00:48:33,755 --> 00:48:35,835 it's a result of champagne having more of 1390 00:48:35,835 --> 00:48:37,775 the surfactant molecules inside it. 1391 00:48:38,074 --> 00:48:39,855 That basically then is quite complicated, 1392 00:48:40,315 --> 00:48:40,795 you know, 1393 00:48:41,275 --> 00:48:43,994 bubble physics, but, basically, that results in all 1394 00:48:43,994 --> 00:48:45,135 these bubbles magically 1395 00:48:45,434 --> 00:48:46,019 kind of 1396 00:48:46,500 --> 00:48:47,480 forming a train 1397 00:48:47,780 --> 00:48:49,320 and coming one after the other. 1398 00:48:49,699 --> 00:48:52,260 Whereas other drinks, terra- nagal. Also has something 1399 00:48:52,260 --> 00:48:53,780 to do with the size of the bubbles 1400 00:48:53,780 --> 00:48:55,699 as well. Yeah. Mhmm. That's right. Yeah. So 1401 00:48:55,699 --> 00:48:57,619 that's all too, with that surface tension and 1402 00:48:57,619 --> 00:48:58,900 all and all those things. 1403 00:48:59,539 --> 00:49:02,304 But, yeah, whereas diff other drinks don't have 1404 00:49:02,304 --> 00:49:03,985 that level of surfactant in it, 1405 00:49:04,864 --> 00:49:06,785 which then, you know, results in the kind 1406 00:49:06,785 --> 00:49:09,025 of bubbles moving a bit more kind of 1407 00:49:09,025 --> 00:49:10,244 in a wavy way. 1408 00:49:11,265 --> 00:49:12,945 But, yeah, the bubbles is also where all 1409 00:49:12,945 --> 00:49:14,065 the a lot of the flavor and the 1410 00:49:14,065 --> 00:49:15,025 taste comes from, 1411 00:49:15,590 --> 00:49:17,269 in champagne. So we've got some popping of 1412 00:49:17,269 --> 00:49:19,429 those bubbles is what gives that kind of 1413 00:49:19,429 --> 00:49:20,329 magic flavour, 1414 00:49:21,110 --> 00:49:21,929 to champagne. 1415 00:49:22,389 --> 00:49:24,710 And and finally, Michael, I wanted to talk 1416 00:49:24,710 --> 00:49:25,210 about, 1417 00:49:26,309 --> 00:49:28,550 I mean, this is, I suppose, an all 1418 00:49:28,550 --> 00:49:30,150 time classic in terms of, 1419 00:49:31,125 --> 00:49:33,204 the, you know, the physics of the real 1420 00:49:33,204 --> 00:49:36,585 world, and that's the the broken spaghetti problem. 1421 00:49:37,844 --> 00:49:39,684 And essentially, the idea here is that if 1422 00:49:39,684 --> 00:49:42,184 you take a piece of spaghetti, dried spaghetti, 1423 00:49:42,565 --> 00:49:45,059 and you hold it at either end, and 1424 00:49:45,059 --> 00:49:47,000 you bend it until it breaks, 1425 00:49:47,460 --> 00:49:49,800 it almost always will break 1426 00:49:50,180 --> 00:49:52,900 into three pieces. No. That's right. Three or 1427 00:49:52,900 --> 00:49:54,579 three or more. Yeah. That's right. Into never 1428 00:49:54,579 --> 00:49:55,880 two. Well, yeah. 1429 00:49:56,180 --> 00:49:58,715 Very rarely two. And I think, you know, 1430 00:49:59,015 --> 00:50:01,355 when when physics students are told this, 1431 00:50:01,735 --> 00:50:03,335 you know, the first thing they do is 1432 00:50:03,335 --> 00:50:04,775 they go home and they get out the 1433 00:50:04,775 --> 00:50:07,655 spaghetti, and they just keep trying and trying 1434 00:50:07,655 --> 00:50:09,515 to break it into two pieces. 1435 00:50:10,055 --> 00:50:12,869 And, it's very, very difficult to do. 1436 00:50:13,190 --> 00:50:13,690 So 1437 00:50:14,150 --> 00:50:16,730 why is that? Why does why does spaghetti 1438 00:50:17,030 --> 00:50:19,750 break into three or more pieces and not 1439 00:50:19,750 --> 00:50:20,250 two? 1440 00:50:20,630 --> 00:50:21,450 Do we know? 1441 00:50:22,070 --> 00:50:24,150 Yeah. I mean, this is actually a question 1442 00:50:24,150 --> 00:50:25,130 that even flummoxed 1443 00:50:26,204 --> 00:50:27,644 Richard Feynman. He was, 1444 00:50:27,965 --> 00:50:30,204 he I think along with his friend, William 1445 00:50:30,204 --> 00:50:33,025 Hillis, they spent apparently, they spent hours, 1446 00:50:33,885 --> 00:50:36,525 just in the kitchen breaking spaghetti and, you 1447 00:50:36,525 --> 00:50:38,525 know, to desperately try and get it into 1448 00:50:38,525 --> 00:50:40,980 two pieces. But, you know, they always found 1449 00:50:40,980 --> 00:50:42,900 that it ended up breaking into three or 1450 00:50:42,900 --> 00:50:43,400 more. 1451 00:50:44,099 --> 00:50:45,539 But they never kind of come up with 1452 00:50:45,539 --> 00:50:47,940 an explanation of what why that kind of 1453 00:50:47,940 --> 00:50:48,440 happened. 1454 00:50:49,780 --> 00:50:51,160 But then actually some researchers, 1455 00:50:51,539 --> 00:50:52,594 at MIT, 1456 00:50:53,215 --> 00:50:55,215 they decided to look into the into that 1457 00:50:55,215 --> 00:50:56,675 process in a bit more detail. 1458 00:50:57,135 --> 00:50:58,414 And then they they came up with this 1459 00:50:58,414 --> 00:51:00,574 kind of elaborate setup where they had, 1460 00:51:01,054 --> 00:51:03,454 one end they had a spaghetti strand, one 1461 00:51:03,454 --> 00:51:04,679 end that was fixed. 1462 00:51:05,639 --> 00:51:08,139 And then it would then basically move into 1463 00:51:08,359 --> 00:51:10,940 another end. So it'd be basically just slowly 1464 00:51:11,000 --> 00:51:11,500 bend. 1465 00:51:13,319 --> 00:51:15,239 And they found actually that there is a 1466 00:51:15,239 --> 00:51:16,300 way of doing it, 1467 00:51:16,839 --> 00:51:19,344 that to create just two pieces, and that's 1468 00:51:19,344 --> 00:51:21,605 if you just do it very, very slowly. 1469 00:51:21,824 --> 00:51:22,565 It sometimes 1470 00:51:23,904 --> 00:51:25,664 can actually break into just two pieces. So 1471 00:51:25,664 --> 00:51:27,025 rather than just, like, you know, getting it, 1472 00:51:27,025 --> 00:51:29,025 but I'm just snapping it. You just do 1473 00:51:29,025 --> 00:51:30,944 it very slowly. But the ultimate way of 1474 00:51:30,944 --> 00:51:31,844 doing it actually 1475 00:51:32,289 --> 00:51:33,029 is to, 1476 00:51:33,730 --> 00:51:36,069 kind of slightly twist the spaghetti strand. 1477 00:51:36,849 --> 00:51:38,929 So the explanation they come with was to 1478 00:51:38,929 --> 00:51:40,769 do with all these kind of twisting waves 1479 00:51:40,769 --> 00:51:41,429 that happen 1480 00:51:41,889 --> 00:51:44,630 that basically dampen the effect of, 1481 00:51:45,329 --> 00:51:47,775 of the spaghetti wanting to break further. 1482 00:51:48,394 --> 00:51:50,255 So these kind of torsional waves, 1483 00:51:50,715 --> 00:51:53,195 by twisting it, these torsional waves stop the 1484 00:51:53,195 --> 00:51:54,255 spaghetti breaking. 1485 00:51:54,954 --> 00:51:56,795 So it only tends to break in two. 1486 00:51:56,795 --> 00:51:58,715 So they found that, actually, if you twist 1487 00:51:58,715 --> 00:52:00,335 the spaghetti on the one end, 1488 00:52:01,962 --> 00:52:03,530 I think it was around about two seventy 1489 00:52:03,530 --> 00:52:05,849 degrees, so not quite a full revolution, but, 1490 00:52:05,849 --> 00:52:07,929 you know, not not far off. And then 1491 00:52:07,929 --> 00:52:10,329 they actually did the same experiment twisted. It 1492 00:52:10,329 --> 00:52:10,829 always 1493 00:52:11,769 --> 00:52:13,550 more or less broke in two pieces. 1494 00:52:14,409 --> 00:52:16,514 And the reason for that is it is 1495 00:52:16,674 --> 00:52:18,694 because the creation of these when it breaks, 1496 00:52:18,755 --> 00:52:21,714 these torsional waves then dampen the effect of 1497 00:52:21,714 --> 00:52:22,214 further, 1498 00:52:23,074 --> 00:52:23,574 breakages. 1499 00:52:24,355 --> 00:52:25,255 And and do 1500 00:52:25,635 --> 00:52:27,014 do they actually know 1501 00:52:27,315 --> 00:52:30,214 why it breaks into three or more pieces? 1502 00:52:30,275 --> 00:52:32,239 The because I suppose, you know, when you 1503 00:52:32,239 --> 00:52:34,639 think about it naively, you think, well, you're 1504 00:52:34,639 --> 00:52:37,539 gonna bend it, and it will break somewhere 1505 00:52:37,599 --> 00:52:38,099 first. 1506 00:52:39,359 --> 00:52:41,219 And then why would it break again? 1507 00:52:41,920 --> 00:52:42,420 Or 1508 00:52:42,974 --> 00:52:44,414 why would it what what are the odds 1509 00:52:44,414 --> 00:52:46,195 of it breaking in two places 1510 00:52:46,575 --> 00:52:48,095 at the same time? You know, both of 1511 00:52:48,095 --> 00:52:49,635 those things seem 1512 00:52:50,175 --> 00:52:50,675 unphysical. 1513 00:52:51,934 --> 00:52:52,894 So are they 1514 00:52:53,855 --> 00:52:55,855 do neither of those things happen? Is it 1515 00:52:55,855 --> 00:52:58,352 something different? So So I think what happens 1516 00:52:58,670 --> 00:53:01,537 what they say is that when so when 1517 00:53:01,537 --> 00:53:04,403 you when you bend a spaghetti strand, it 1518 00:53:04,403 --> 00:53:07,270 creates these when they call them bending waves, 1519 00:53:07,270 --> 00:53:10,136 basically. And these propagate when it when it's 1520 00:53:10,136 --> 00:53:12,454 bent, when it snaps, these bending waves then 1521 00:53:12,454 --> 00:53:14,934 propagate down the strand, and then it kind 1522 00:53:14,934 --> 00:53:16,795 of re results in more, 1523 00:53:17,414 --> 00:53:19,815 breakages because of these kind of these waves 1524 00:53:19,815 --> 00:53:22,055 are produced. But that's then what the that 1525 00:53:22,055 --> 00:53:23,894 these kind of these twisting waves or the 1526 00:53:23,894 --> 00:53:27,029 torsional waves actually counteract the bending waves. 1527 00:53:27,489 --> 00:53:29,089 So that's the way then to get around 1528 00:53:29,089 --> 00:53:29,909 it is because, 1529 00:53:31,250 --> 00:53:33,670 the bending waves are dampened by this torsional 1530 00:53:34,289 --> 00:53:36,929 waves. Yeah. It's on, but, Well, that would 1531 00:53:37,170 --> 00:53:39,489 yeah. Yeah. That's interesting because, you know, it 1532 00:53:39,489 --> 00:53:41,534 just popped into my mind that, 1533 00:53:42,174 --> 00:53:43,855 if you actually take a big bunch of 1534 00:53:43,855 --> 00:53:44,355 spaghetti 1535 00:53:45,214 --> 00:53:46,275 and break it, 1536 00:53:46,574 --> 00:53:49,214 it will break into two. Every almost every 1537 00:53:49,214 --> 00:53:51,534 strand will break into two. So I suppose 1538 00:53:51,534 --> 00:53:54,034 when you're grabbing the spaghetti and, 1539 00:53:55,219 --> 00:53:56,760 sort of squeezing it together, 1540 00:53:57,139 --> 00:53:59,780 you're probably dampening You're probably dampening those those 1541 00:53:59,780 --> 00:54:01,940 breakages. Yeah. That's that's yeah. That's probably the 1542 00:54:01,940 --> 00:54:03,699 case, actually. Yeah. So yeah. That's one way 1543 00:54:03,699 --> 00:54:05,460 you're getting around it, maybe. Get the whole 1544 00:54:05,460 --> 00:54:08,244 packet and, bend it. Yeah. Yeah. Well, that's 1545 00:54:08,324 --> 00:54:09,284 I mean, I you know, I have to 1546 00:54:09,284 --> 00:54:10,485 say I'm I'm sure this is, 1547 00:54:11,204 --> 00:54:13,925 I've I've I've I've probably insulted the Italian 1548 00:54:13,925 --> 00:54:14,824 nation again 1549 00:54:15,284 --> 00:54:17,545 by saying that when I do cook spaghetti, 1550 00:54:17,605 --> 00:54:20,164 I do break it in half and cook 1551 00:54:20,164 --> 00:54:20,664 it. 1552 00:54:21,364 --> 00:54:22,344 Yeah, I've said 1553 00:54:22,700 --> 00:54:24,460 I I was planning on going to Italy 1554 00:54:24,460 --> 00:54:26,800 next year, but maybe Maybe not anymore. 1555 00:54:27,579 --> 00:54:30,079 My visa will not be granted. Yeah. 1556 00:54:30,380 --> 00:54:33,420 Well, thanks thanks, Michael. Thanks so much. And, 1557 00:54:33,579 --> 00:54:36,860 actually, there's more about, Italian cuisine in, 1558 00:54:37,664 --> 00:54:39,344 in your book because you've got a wonderful 1559 00:54:39,344 --> 00:54:41,184 section about pizza as well and how to 1560 00:54:41,184 --> 00:54:43,585 cook a perfect pizza. But, you know, I'm 1561 00:54:43,585 --> 00:54:45,905 afraid we we just don't have time to 1562 00:54:45,905 --> 00:54:49,045 cover that. So Michael's book is called Physics 1563 00:54:49,344 --> 00:54:51,344 Around the Clock, and it's out now. Is 1564 00:54:51,344 --> 00:54:52,869 that right, Michael? Yeah. I suppose it's out 1565 00:54:52,869 --> 00:54:53,610 in The UK, 1566 00:54:54,309 --> 00:54:56,309 now, and it will be published in The 1567 00:54:56,309 --> 00:54:58,570 US in April 2026. 1568 00:54:58,630 --> 00:55:00,469 Okay. And I'll put a link, 1569 00:55:00,869 --> 00:55:02,869 at least to the to The UK version 1570 00:55:02,869 --> 00:55:04,869 in the notes for the podcast. Thanks a 1571 00:55:04,869 --> 00:55:06,789 lot for coming on and talking about, 1572 00:55:07,485 --> 00:55:10,144 some wonderful physics, Michael. Thanks, Hamish. 1573 00:55:17,644 --> 00:55:20,840 That was Physics World's Michael Banks. His latest 1574 00:55:20,840 --> 00:55:23,019 book is Physics Around the Clock, 1575 00:55:23,400 --> 00:55:26,920 Adventures in the Science of Everyday Living, and 1576 00:55:26,920 --> 00:55:29,179 it's published by the History Press. 1577 00:55:29,480 --> 00:55:31,400 I'll put a link to the book in 1578 00:55:31,400 --> 00:55:32,699 the podcast notes. 1579 00:55:33,174 --> 00:55:36,074 Thanks to Michael for joining me today and 1580 00:55:36,135 --> 00:55:38,154 to our producer Fred Ailes. 1581 00:55:38,775 --> 00:55:41,275 And thank you for listening to this podcast, 1582 00:55:41,654 --> 00:55:42,554 which is supported 1583 00:55:42,855 --> 00:55:43,914 by the APS 1584 00:55:44,454 --> 00:55:46,074 Global Physics Summit. 1585 00:55:46,579 --> 00:55:50,039 To continue advancing physics beyond this podcast, 1586 00:55:50,579 --> 00:55:54,739 participate in the APS Global Physics Summit on 1587 00:55:54,739 --> 00:55:56,829 March 1588 00:55:56,829 --> 00:55:58,920 2026 1589 00:55:59,204 --> 00:56:00,505 in Denver, Colorado, 1590 00:56:01,204 --> 00:56:02,265 and online. 1591 00:56:03,125 --> 00:56:03,625 Experience 1592 00:56:03,925 --> 00:56:04,744 high impact 1593 00:56:05,045 --> 00:56:06,184 scientific sessions, 1594 00:56:06,565 --> 00:56:07,864 networking opportunities, 1595 00:56:08,485 --> 00:56:08,985 workshops, 1596 00:56:09,364 --> 00:56:11,305 and community building events 1597 00:56:11,765 --> 00:56:14,105 designed for every career stage. 1598 00:56:15,039 --> 00:56:17,599 Learn how you can attend and shape the 1599 00:56:17,599 --> 00:56:22,659 future of physics at summit.aps.org.