A Martian aurora, how the universe fades away, Heisenberg on holiday, physics of fake coins

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Hello, and welcome to the Physics World weekly

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podcast. I'm Hamish Johnston.

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In this episode, I'm joined by my colleagues

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Margaret Harris and Matin Durrani to talk about

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what's new in the world of physics.

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So first up, we've got Margaret who's going

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to take us to Mars

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and talk about the first observation

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of an aurora

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from the surface

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of the red planet. Hi, Margaret.

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Hi, Hamish.

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So Margaret, can you

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first remind us what an aurora is? I

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mean, people have been seeing lots of them

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here on Earth,

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over the over the past few months. But

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what what are people seeing?

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Well, what you're seeing is the

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manifestation

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of an interaction between our planet's magnetosphere

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and the solar wind. Okay. So what's the

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magnetosphere?

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The magnetosphere

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is sort of an envelope that surrounds Earth,

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and it's caused by the Earth being,

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basically, a big gigantic magnet. So there's a

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magnetic dynamo in the center of the Earth.

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It's probably due to the fact that we

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have a liquid iron core,

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creating a magnetic field.

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And so this is great. This is great

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because it protects us from the solar wind,

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which is a stream of charged particles

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coming from the sun.

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And when that stream of charged particles from

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the sun slams into our planet's magnetosphere,

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it it it produces the aurora borealis if

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the if you're in the Northern Hemisphere and

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or the aurora australis if you're down south.

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Okay. And and so what what has been

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seen on Mars? I think we when we

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were first discussing this paper a few weeks

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ago, we were really hoping that there was

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going to be a fantastic

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image of, you know, the classic

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shimmering

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red and green lights,

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above the Martian surface.

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Is that essentially

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what

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what what has been seen

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on Mars?

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Okay. Well, so first things, in order to

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see something really

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shimmering and gorgeous, you need a couple things.

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One, you need a solar storm that's big

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enough because not every time,

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not every solar storm is big enough to

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create the, you know, tremendous

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sort of light show that we've been seeing

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recently here on Earth because,

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we're at a solar maximum, as in the

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maximum of

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So first off, the solar storm that produced

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the aurora that was seen on Mars was

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a really minor one. It may have turned

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the sky just sort of, like, faintly greenish.

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So that's hard to detect even for for

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for the naked eye. It's hard even to

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detect for cameras. And the other thing is

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that this was seen on the surface of

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Mars by the Perseverance rover.

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And the Perseverance rover is a great little

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instrument, but it's mostly designed to be looking

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down.

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It's designed to do geology on Mars and

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to do all sorts of fantastic stuff associated

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with, you know, trying to work out whether

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life ever existed on Mars.

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It's not really designed to look up.

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And it's not designed to do observations in

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the dark. You don't do much geology in

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the dark.

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So

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the cameras there were not really optimized to

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pick up, you know, a really fantastic aurora,

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but they did pick up something. They picked

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up the fact that the sky turned from

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being its normal subdark color to being sort

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of vaguely grayish green. And that's important because

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we'd never seen an aurora from the surface

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of another world before.

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We'd seen auroras

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from orbits

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on all sorts of of planets in the

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in the solar system, any any,

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planet that has a magnetosphere,

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which interestingly, Mars doesn't really have its magnetosphere

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in the same sense that Earth does, but

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it does have a weak magnetosphere.

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It's called a hybrid magnetosphere

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that's generated not by this in interior planetary

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dynamo, but by some weakly, residually magnetic rocks,

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I believe in its southern hemisphere,

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and by just the fact that Mars is

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a big object.

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And so it tends to sort of warp

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the solar wind into and the magnetic fields

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that come from there sort of get warped

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around it and kinda gathered around it like

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a like a sort of gauzy summer shawl.

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So it has this very, very weak magnetic

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field. It's although it's not strong enough to

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protect,

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objects on the surface of Mars from intense

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radiation, from the cosmic rays, and from the

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solar wind, it is strong enough to produce

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an aurora. And that's what Perseverance saw.

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I see. And, I mean, it sounds to

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me that this was was was this sort

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of an accidental

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or a serendipitous

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observation that I don't know. They they just

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happened to leave the cameras on at night

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and, and and they caught this, you know,

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this is sort of the equivalent of the

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of the doorbell cam here on Earth or

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or,

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were they actually looking for it? Oh, they

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were definitely looking for it. They were definitely

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looking very hard for it. And the thing

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is that, you know, Perseverance is a busy

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little dude. You know? It can't just keep

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its cameras looking up just in case there

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might be an aurora up there. Mhmm. They

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had to have some really good predictions

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of

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when this to first for actually, first, go

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back a little bit. First, they had to

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see the solar storm

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that produced the aurora,

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and then they had to, work with some

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scientists at NASA's Goddard flight Space Flight Center

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to,

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understand when that aurora was gonna hit Mars.

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It takes about three days, but they can

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kinda predict it to within a few hours.

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And then they had to make a decision,

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like, is this aurora big enough that,

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Perseverance is not very optimized for looking at

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the sky cameras could see something. And then

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they had to request time and Perseverance, get

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it to stop doing whatever else it was

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doing and to look up at the sky.

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And then they had to be lucky, basically.

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They had to

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have all those things happen at just the

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right time. And I think it took him

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about,

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I think it took him about four goes

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before they managed to actually capture an aurora

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on Mars. But this is important. It's the

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first one to be done, and it's also

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the first aurora to be seen

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anywhere other than the Earth that's been measured

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in visible

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light wavelength rather than in UV light.

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And that's important because visible light cameras are

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a lot cheaper

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than UV cameras.

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So if we can do these observations with

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nice cheap cameras,

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then we should be able to do do

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more of them, essentially.

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Right. And, it is I mean, it does

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seem to be a very good time here

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on Earth to be to be out looking

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for Aurora. I mean, I've seen reports

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in North America where, you know, even this

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time of year,

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aurora have been spotted,

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further south than forty five degrees north, which

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is, you know, that's closer to the Equator

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than the North Pole, which, you know, is

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is pretty impressive. And I'm guessing that has

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to do with some increased solar activity

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at the time. So,

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are

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the the people who who use Perseverance,

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are are they geared up for more observations?

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And I'm guessing they're probably looking for time

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when they know there's gonna be a big

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solar storm,

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that that to to turn

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the the the rover's cam cameras skyward. Is

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that is that the sort of thing that

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that's going to be next

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for, for people there?

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I think they certainly want to do that.

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Whether they'll be able to get time on

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on perseverance is, you know, another question. It

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it's as I said, it has lots of

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other priorities.

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But, definitely, this is probably gonna be hopefully

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the first of many detections of aurora,

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by robots that are

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by robots that are exploring,

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the surfaces and the atmospheres by the planets.

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Oh, that's great. That's really interesting.

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And staying in space, but sort of looking

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into the far, far future,

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you've also got an update for us about

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the ultimate fate of the universe

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and the news that it might

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not be as long lived as previously expected.

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And I think this has something to do

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with white dwarf stars,

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which are expected to persist

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for an extraordinarily

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long time.

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And

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when I say extraordinarily long, I think we're

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talking about ten to the

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thousands or even tens of thousands of years.

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So so why are white dwarfs

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important

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when it comes to understanding the the future

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of the universe?

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Okay. So white dwarfs are lower mass stars

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in the final stage of their lives. They

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weren't massive enough to collapse into a neutron

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star star or a black hole. They're just

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kinda hanging out, gently glowing from the residual

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heat. They're not doing any thermonuclear fusion or

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anything exciting.

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And that means that as long as they

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don't get cannibalized by a companion star or

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fall into a black hole or something weird

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and, also, I should say, as long as

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our universe doesn't undergo some sort of big

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crunch, this is not this this story is

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not to do with the sort of grand

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scale cosmology. It's really about white dwarf stars,

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the physics of white dwarf stars. So as

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long as those things don't happen, they can

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last a really long time.

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But crucially, a really long time is not

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the same thing as forever. There is a

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few things that could make a white dwarf

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star disappear.

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So one of them is if protons decay.

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Various theories predict that protons should decay,

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00:10:18,699 --> 00:10:21,100
but nobody's ever seen that happen, and it's

273
00:10:21,100 --> 00:10:22,779
not for lack of trying. There were several

274
00:10:22,779 --> 00:10:24,860
experiments looking for proton decay, I think, in

275
00:10:24,860 --> 00:10:26,559
the nineteen eighties and nineteen nineties.

276
00:10:27,835 --> 00:10:29,355
But the best we can say that if

277
00:10:29,355 --> 00:10:30,815
if protons do decay,

278
00:10:31,434 --> 00:10:33,115
they do it on a time scale that's

279
00:10:33,115 --> 00:10:35,514
longer than our experiments so far have been

280
00:10:35,514 --> 00:10:38,335
able to measure. Okay. That's proton decay.

281
00:10:39,035 --> 00:10:40,980
The other way of making a white dwarf

282
00:10:41,059 --> 00:10:43,879
star disappear is via process called piconuclear

283
00:10:44,259 --> 00:10:44,759
fusion.

284
00:10:45,299 --> 00:10:46,820
I had never heard of this before I

285
00:10:46,820 --> 00:10:48,740
saw this story, but it's derived from the

286
00:10:48,740 --> 00:10:50,759
Greek word pyknos, meaning dense.

287
00:10:51,220 --> 00:10:52,360
So piconuclear

288
00:10:52,740 --> 00:10:55,379
fusion is nuclear fusion that only happens in

289
00:10:55,379 --> 00:10:56,679
extremely dense material

290
00:10:57,514 --> 00:10:59,615
like you get inside a white dwarf star.

291
00:11:00,315 --> 00:11:02,875
And it's kind of a complicated process, but,

292
00:11:02,875 --> 00:11:05,514
essentially, what's happening is that the nuclei inside

293
00:11:05,514 --> 00:11:08,715
white dwarfs are oscillating around their zero point

294
00:11:08,715 --> 00:11:09,179
energy.

295
00:11:09,899 --> 00:11:12,620
And sometimes these oscillations are actually enough to

296
00:11:12,620 --> 00:11:14,940
allow them to fuse. There's some quantum tunneling

297
00:11:14,940 --> 00:11:15,440
involved.

298
00:11:15,980 --> 00:11:17,980
And if that happened to matter under normal

299
00:11:17,980 --> 00:11:18,480
conditions,

300
00:11:18,860 --> 00:11:20,700
like, stuff would be fusing all over the

301
00:11:20,700 --> 00:11:22,795
place. But fortunately, that doesn't happen. It only

302
00:11:22,795 --> 00:11:25,355
happens really in inside white dwarf stars, or

303
00:11:25,355 --> 00:11:28,154
it's only important, let's say, inside white dwarf

304
00:11:28,154 --> 00:11:28,654
stars.

305
00:11:29,514 --> 00:11:30,014
And

306
00:11:30,955 --> 00:11:33,274
the consequence of pyronuclear fusion is that it

307
00:11:33,274 --> 00:11:35,774
turns the carbon and white dwarf star cores

308
00:11:36,269 --> 00:11:39,230
into nickel, which then decays to, I think

309
00:11:39,230 --> 00:11:41,709
it's iron 56. Don't quote me on that.

310
00:11:41,709 --> 00:11:43,169
I think it's iron 56

311
00:11:43,309 --> 00:11:44,529
by emitting a positron.

312
00:11:45,389 --> 00:11:47,230
And once you've got that iron core, you've

313
00:11:47,230 --> 00:11:48,990
no longer got a white dwarf star. You've

314
00:11:48,990 --> 00:11:50,315
got a black dwarf star,

315
00:11:50,695 --> 00:11:53,014
which is a theoretical object that's never before

316
00:11:53,014 --> 00:11:53,754
been seen,

317
00:11:54,134 --> 00:11:56,634
not just because it's dark, but because

318
00:11:57,095 --> 00:11:59,115
the time required for that to happen

319
00:11:59,575 --> 00:12:01,414
is actually longer than the lifetime of the

320
00:12:01,414 --> 00:12:02,634
universe so far.

321
00:12:03,014 --> 00:12:05,095
So even if it's possible, it hasn't happened

322
00:12:05,095 --> 00:12:05,340
yet.

323
00:12:06,779 --> 00:12:08,940
I see. And and so the idea here

324
00:12:08,940 --> 00:12:10,879
is that the the end of the universe

325
00:12:11,019 --> 00:12:13,980
that we're talking about is when all is

326
00:12:13,980 --> 00:12:16,399
when these white dwarf stars go

327
00:12:17,100 --> 00:12:19,019
that they don't produce any more light. They

328
00:12:19,019 --> 00:12:19,759
go dark.

329
00:12:20,095 --> 00:12:22,495
It's even weirder than that because so while

330
00:12:22,495 --> 00:12:23,615
we're going out on a out on a

331
00:12:23,615 --> 00:12:27,695
speculative limb here, turning carbon into iron leads

332
00:12:27,695 --> 00:12:29,634
to a loss of electron degeneracy

333
00:12:30,014 --> 00:12:31,475
pressure, which is what's keeping

334
00:12:31,855 --> 00:12:34,289
the black door from collapsing in on itself.

335
00:12:35,089 --> 00:12:37,649
And eventually I mean, we're talking very, very

336
00:12:37,649 --> 00:12:38,149
eventually.

337
00:12:38,929 --> 00:12:41,190
That will reduce the maximum mass

338
00:12:41,570 --> 00:12:44,049
that the black dwarf star can have before

339
00:12:44,049 --> 00:12:44,629
it collapses.

340
00:12:45,250 --> 00:12:46,470
It's called the Chandrasekhar

341
00:12:46,929 --> 00:12:47,429
limit.

342
00:12:47,754 --> 00:12:49,434
Right. And so that will actually make the

343
00:12:49,434 --> 00:12:50,894
black dwarf star unstable.

344
00:12:51,914 --> 00:12:53,595
So this is the other process that could

345
00:12:53,595 --> 00:12:56,574
cause otherwise stable white dwarf stars to disappear,

346
00:12:56,875 --> 00:12:59,294
and it's it's really slow. It's you mentioned

347
00:12:59,674 --> 00:13:02,074
it would take somewhere between ten to the

348
00:13:02,074 --> 00:13:03,360
eleven hundred years

349
00:13:03,839 --> 00:13:06,339
and ten to the thirty two thousand years

350
00:13:06,959 --> 00:13:09,059
depending on the mass of the black dwarf.

351
00:13:09,120 --> 00:13:10,879
So higher masses would be quicker because they

352
00:13:10,879 --> 00:13:12,899
would reach the Chandrasekhar limit quicker.

353
00:13:13,600 --> 00:13:16,019
Right. Okay. And that that is a very

354
00:13:16,079 --> 00:13:17,759
long time. That is a very long time.

355
00:13:17,759 --> 00:13:19,875
So those those are the so,

356
00:13:21,295 --> 00:13:23,535
proton decay, if it happens, is actually relatively

357
00:13:23,535 --> 00:13:26,254
quick. If you're if protons don't decay and

358
00:13:26,254 --> 00:13:28,654
piconuclear fusion is your only mechanism, that's really,

359
00:13:28,654 --> 00:13:29,475
really slow.

360
00:13:30,014 --> 00:13:30,514
Right.

361
00:13:31,055 --> 00:13:32,995
But there's some new research now,

362
00:13:33,950 --> 00:13:36,850
where some physicists have looked at a process,

363
00:13:37,789 --> 00:13:40,370
or a phenomenon called Hawking radiation.

364
00:13:41,309 --> 00:13:41,629
And,

365
00:13:42,269 --> 00:13:45,950
they've they've applied this to, white dwarf stars

366
00:13:45,950 --> 00:13:48,294
in the in the far future, and and

367
00:13:48,294 --> 00:13:50,615
they've come up with a a much, much,

368
00:13:50,615 --> 00:13:51,115
much

369
00:13:51,495 --> 00:13:51,995
shorter

370
00:13:52,375 --> 00:13:53,915
lifetime. Still very long,

371
00:13:54,375 --> 00:13:56,455
but much, much shorter. So so what is

372
00:13:56,455 --> 00:13:59,335
Hawking radiation? How does it fit in to,

373
00:13:59,815 --> 00:14:02,634
to the life's lifetime of, of these stars?

374
00:14:03,460 --> 00:14:06,100
Okay. So if you've heard of Hawking radiation,

375
00:14:06,100 --> 00:14:08,500
it's probably in the context of black holes

376
00:14:08,500 --> 00:14:10,899
because that's where it was first formulated by

377
00:14:10,899 --> 00:14:11,720
Stephen Hawking,

378
00:14:12,419 --> 00:14:14,740
building on some ideas of another theorist called

379
00:14:14,740 --> 00:14:15,559
Jacob Bekenstein.

380
00:14:16,855 --> 00:14:20,134
The idea is that particle antiparticle pairs are

381
00:14:20,134 --> 00:14:22,295
popping in and out of the quantum vacuum

382
00:14:22,295 --> 00:14:24,934
all the time. They borrow energy from the

383
00:14:24,934 --> 00:14:27,254
vacuum to to appear, and then they almost

384
00:14:27,254 --> 00:14:29,754
immediately give it back again because they annihilate

385
00:14:29,815 --> 00:14:30,450
and they disappear.

386
00:14:31,649 --> 00:14:32,149
However,

387
00:14:33,090 --> 00:14:35,490
if one half of that pair happens to

388
00:14:35,490 --> 00:14:38,070
drop over a black hole's event horizon

389
00:14:38,610 --> 00:14:41,190
in that brief period between coming into existence

390
00:14:41,490 --> 00:14:42,230
and annihilating,

391
00:14:42,850 --> 00:14:44,690
then it won't ever be able to recombine

392
00:14:44,690 --> 00:14:46,975
with its partner, so it'll take away some

393
00:14:46,975 --> 00:14:49,214
energy. And this is the mechanism by which

394
00:14:49,214 --> 00:14:51,955
black holes radiate away their mass energy

395
00:14:52,334 --> 00:14:53,154
and shrink

396
00:14:53,455 --> 00:14:54,995
rather than continually growing.

397
00:14:56,014 --> 00:14:58,199
But, obviously, a black hole is not the

398
00:14:58,199 --> 00:14:59,500
same thing as a white dwarf.

399
00:14:59,879 --> 00:15:02,600
But the kicker is that Hawking radiation doesn't

400
00:15:02,600 --> 00:15:04,299
just happen to black holes.

401
00:15:05,720 --> 00:15:07,399
A couple of years ago, the black hole

402
00:15:07,399 --> 00:15:11,579
expert Heino Falke, quantum physicist Michael von Drac,

403
00:15:11,735 --> 00:15:14,855
and mathematician Walter von Sudekum. Apologies. Their Dutch

404
00:15:14,855 --> 00:15:16,335
names I don't know speak Dutch. So if

405
00:15:16,335 --> 00:15:18,215
I pronounce those incorrectly, I'm very sorry. Don't

406
00:15:18,215 --> 00:15:20,555
even try, Margaret. Don't even try. Try.

407
00:15:20,935 --> 00:15:22,455
I'll do my best. I'll do my best.

408
00:15:23,175 --> 00:15:25,570
So they worked out that this whole particle

409
00:15:25,570 --> 00:15:27,590
falling over the event horizon scenario

410
00:15:28,129 --> 00:15:30,710
is really just an extreme case of particles

411
00:15:30,769 --> 00:15:33,889
not being able to annihilate because gravitational tidal

412
00:15:33,889 --> 00:15:35,970
forces have pulled them far away from each

413
00:15:35,970 --> 00:15:36,470
other.

414
00:15:37,009 --> 00:15:37,909
And in principle,

415
00:15:38,725 --> 00:15:39,544
that kind of

416
00:15:40,004 --> 00:15:41,705
gravitational tidal force separation

417
00:15:42,565 --> 00:15:44,664
can happen at least some of the time

418
00:15:45,125 --> 00:15:47,125
in the vicinity of any object with a

419
00:15:47,125 --> 00:15:48,345
gravitational field,

420
00:15:48,725 --> 00:15:51,284
and that includes white dwarf stars. In fact,

421
00:15:51,284 --> 00:15:52,350
it includes humans

422
00:15:52,829 --> 00:15:54,589
because you and I, we also have a

423
00:15:54,589 --> 00:15:57,250
gravitational field. It's very tiny, but it exists.

424
00:15:57,949 --> 00:15:58,449
And

425
00:15:59,230 --> 00:15:59,730
so

426
00:16:00,190 --> 00:16:02,350
this trio worked out it would take a

427
00:16:02,350 --> 00:16:04,909
white dwarf star around ten to the seventy

428
00:16:04,909 --> 00:16:05,569
eight years

429
00:16:05,949 --> 00:16:07,889
to dissipate via Hawking radiation,

430
00:16:08,804 --> 00:16:10,325
which is it's a hell of a long

431
00:16:10,325 --> 00:16:11,845
time, but it's a lot shorter than ten

432
00:16:11,845 --> 00:16:13,764
to eleven to the eleven hundred years or

433
00:16:13,764 --> 00:16:15,285
ten to the thirty two thousand years you

434
00:16:15,285 --> 00:16:17,065
get with piconuclear fusion reactions.

435
00:16:18,165 --> 00:16:20,264
And as a side note, they also calculated,

436
00:16:20,325 --> 00:16:21,945
you know, somewhat tongue in cheek,

437
00:16:22,325 --> 00:16:22,919
that if

438
00:16:23,559 --> 00:16:26,039
Hawking radiation was the only process involved, you

439
00:16:26,039 --> 00:16:27,639
know, you got rid of all of chemistry

440
00:16:27,639 --> 00:16:30,039
and biology and all sort of various physical

441
00:16:30,039 --> 00:16:30,919
events that could,

442
00:16:31,480 --> 00:16:33,259
cause them interrupt this process,

443
00:16:33,959 --> 00:16:34,459
then

444
00:16:34,759 --> 00:16:35,980
it would take a human,

445
00:16:36,785 --> 00:16:38,384
which is obviously less dense than a white

446
00:16:38,384 --> 00:16:39,125
dwarf star,

447
00:16:39,504 --> 00:16:42,245
around ten to the ninety years to

448
00:16:42,625 --> 00:16:45,125
dissipate entirely via Hawking radiation.

449
00:16:45,665 --> 00:16:47,985
Now I don't think that's there's gonna be

450
00:16:47,985 --> 00:16:50,610
much of an interesting universe around in ten

451
00:16:50,610 --> 00:16:52,129
to the ninety years. After all, we've just

452
00:16:52,129 --> 00:16:54,290
shown that white dwarf stars, even white dwarf

453
00:16:54,290 --> 00:16:55,990
stars, will have winked out of existence

454
00:16:56,450 --> 00:16:59,090
in, ten to the seventy eight years. But

455
00:16:59,090 --> 00:16:59,750
in principle,

456
00:17:00,210 --> 00:17:02,389
that is how long a a a human

457
00:17:02,529 --> 00:17:04,690
could or a human sized object made of

458
00:17:04,690 --> 00:17:07,304
water, let's say, could, could last in the

459
00:17:07,304 --> 00:17:07,804
universe.

460
00:17:08,505 --> 00:17:10,585
And, of course, that that doesn't take into

461
00:17:10,585 --> 00:17:11,085
consideration

462
00:17:11,384 --> 00:17:12,684
these sort of cosmological

463
00:17:13,304 --> 00:17:15,704
Oh, yeah. Issues Yeah. Yeah. About whether whether

464
00:17:15,704 --> 00:17:17,644
the universe is going to keep on

465
00:17:17,960 --> 00:17:20,519
keep on expanding or if it's going to

466
00:17:20,519 --> 00:17:22,759
sort of bounce back or this is just

467
00:17:22,759 --> 00:17:23,500
how long

468
00:17:24,279 --> 00:17:26,299
stuff in the universe can actually

469
00:17:26,680 --> 00:17:29,720
exist. Yeah. Exactly. Exactly. Yeah. Which is still

470
00:17:29,720 --> 00:17:31,815
interesting to think about. I mean Oh, yeah.

471
00:17:31,815 --> 00:17:34,054
Yeah. Yeah. Well, I mean, it is very

472
00:17:34,054 --> 00:17:36,694
interesting because, you know, I'm guessing that by

473
00:17:36,694 --> 00:17:39,035
doing these calculations on Hawking radiation,

474
00:17:39,815 --> 00:17:42,474
they're, you know, sort of moving our knowledge

475
00:17:42,535 --> 00:17:43,035
forward

476
00:17:43,559 --> 00:17:44,059
of,

477
00:17:45,000 --> 00:17:47,179
you know, the sort of the interplay between

478
00:17:47,480 --> 00:17:48,919
quantum mechanics and,

479
00:17:50,200 --> 00:17:51,339
and general relativity

480
00:17:51,799 --> 00:17:54,440
Yeah. Which is always very interesting. Well, thanks,

481
00:17:54,440 --> 00:17:56,779
Margaret. Thanks for coming on and talking about

482
00:17:57,325 --> 00:18:00,845
about Aurora on Mars and the age of,

483
00:18:01,244 --> 00:18:03,744
objects in the universe. And you can find,

484
00:18:04,445 --> 00:18:07,005
both of those articles written by Margaret. They're

485
00:18:07,005 --> 00:18:09,005
both written by you, Margaret. Is that right?

486
00:18:09,005 --> 00:18:11,565
Yep. Yeah. Both articles written by Margaret about

487
00:18:11,565 --> 00:18:12,065
these,

488
00:18:12,730 --> 00:18:15,710
subjects on the Physics World website. Thanks.

489
00:18:16,490 --> 00:18:17,309
Thanks, Hamish.

490
00:18:25,210 --> 00:18:27,609
Now let's move from the future to the

491
00:18:27,609 --> 00:18:29,224
past and an important

492
00:18:29,525 --> 00:18:31,464
moment in physics history.

493
00:18:32,085 --> 00:18:34,505
Matin, you'll soon be traveling to the German

494
00:18:34,565 --> 00:18:35,785
island of Helgoland

495
00:18:36,484 --> 00:18:38,105
for a hundredth anniversary

496
00:18:38,644 --> 00:18:39,144
celebration.

497
00:18:39,924 --> 00:18:41,545
What happened in Helgoland

498
00:18:42,190 --> 00:18:44,049
back in 1925?

499
00:18:44,750 --> 00:18:47,630
Well, it was in June 1925 that Werner

500
00:18:47,630 --> 00:18:48,130
Heisenberg,

501
00:18:48,430 --> 00:18:50,609
who at the time was a young postdoc

502
00:18:50,670 --> 00:18:51,970
at the University of Gottingen,

503
00:18:52,590 --> 00:18:54,750
he suffered from a really bad bout of

504
00:18:54,750 --> 00:18:55,570
hay fever.

505
00:18:55,904 --> 00:18:58,945
But he famously asked his supervisor, Max Born,

506
00:18:58,945 --> 00:19:00,865
if he could go to this island for

507
00:19:00,865 --> 00:19:02,565
two weeks to recover

508
00:19:03,345 --> 00:19:05,184
from the allergies that he had because it's

509
00:19:05,184 --> 00:19:06,805
an island in the North Sea.

510
00:19:07,184 --> 00:19:09,420
I've looked on Google Maps. It's probably about,

511
00:19:09,900 --> 00:19:11,980
an hour off the coast of Germany. And,

512
00:19:11,980 --> 00:19:13,119
you know, it's very windswept,

513
00:19:13,500 --> 00:19:14,799
and it's very isolated.

514
00:19:15,180 --> 00:19:17,500
There's no trees in the sea, so no

515
00:19:17,500 --> 00:19:18,000
pollen.

516
00:19:18,460 --> 00:19:20,539
Exactly. Yeah. Yeah. So he went he went

517
00:19:20,539 --> 00:19:22,539
there, and it was on this island in

518
00:19:22,539 --> 00:19:24,285
June 1925 that

519
00:19:24,845 --> 00:19:25,345
he,

520
00:19:25,884 --> 00:19:26,684
had this,

521
00:19:27,085 --> 00:19:29,325
amazing insights. His ideas that he'd been working

522
00:19:29,325 --> 00:19:31,505
on came together, and he formulated

523
00:19:31,805 --> 00:19:33,664
the ideas of quantum mechanics,

524
00:19:34,205 --> 00:19:36,539
you know, proper mathematical framework for

525
00:19:37,100 --> 00:19:39,180
all these weird quantum effects that people were

526
00:19:39,180 --> 00:19:39,680
seeing.

527
00:19:40,779 --> 00:19:42,220
And so, yeah, that was a hundred years

528
00:19:42,220 --> 00:19:42,720
ago.

529
00:19:43,259 --> 00:19:45,500
So a very famous moment in history of

530
00:19:45,500 --> 00:19:47,980
physics that is being celebrated this year. That's

531
00:19:47,980 --> 00:19:50,480
right. In the the international year the UN's

532
00:19:50,539 --> 00:19:53,005
international year. UNESCO, is it? Yeah.

533
00:19:53,545 --> 00:19:55,085
UNESCO, which is a UN agency,

534
00:19:55,465 --> 00:19:58,684
the International Year of Quantum Science and Technology.

535
00:19:59,384 --> 00:20:02,025
And and so this was matrix mechanics that

536
00:20:02,025 --> 00:20:04,345
he came up with. This is this this

537
00:20:04,345 --> 00:20:05,865
idea of, of,

538
00:20:08,259 --> 00:20:08,759
representing,

539
00:20:09,940 --> 00:20:11,299
reality in terms of,

540
00:20:11,940 --> 00:20:15,320
vectors and and matrices and multiplying them together

541
00:20:15,380 --> 00:20:17,299
and, and all that sort of stuff that

542
00:20:17,299 --> 00:20:19,400
you learn, I suppose, as an undergraduate.

543
00:20:20,054 --> 00:20:20,294
And,

544
00:20:20,855 --> 00:20:22,214
and and that was a big deal, wasn't

545
00:20:22,214 --> 00:20:25,014
it? Because before that, wasn't there the, I

546
00:20:25,014 --> 00:20:26,855
mean, I might have the the lingo wrong,

547
00:20:26,855 --> 00:20:30,375
but the old quantum mechanics where people didn't

548
00:20:30,375 --> 00:20:32,855
really understand what was going on. They knew

549
00:20:32,855 --> 00:20:35,470
that physics was really weird. And it was

550
00:20:35,470 --> 00:20:37,470
only when Heisenberg sort of wrote down this

551
00:20:37,470 --> 00:20:39,089
matrix mechanics that,

552
00:20:39,950 --> 00:20:42,369
it all start started to make sense or

553
00:20:42,509 --> 00:20:44,750
well, started to make sense. It still doesn't

554
00:20:44,750 --> 00:20:46,769
make sense, does it? Quantum mechanics,

555
00:20:47,149 --> 00:20:47,649
famously.

556
00:20:48,029 --> 00:20:49,964
If you think you understand it, you don't.

557
00:20:50,924 --> 00:20:53,585
But, yeah. So so a very, very exciting,

558
00:20:54,845 --> 00:20:55,744
a very exciting,

559
00:20:56,365 --> 00:20:57,884
time, 1925

560
00:20:57,884 --> 00:21:00,865
in Helgoland. So Helgoland is it's an island.

561
00:21:01,325 --> 00:21:03,484
It's off the the West Coast Of Germany,

562
00:21:03,484 --> 00:21:05,505
so it's in the North Sea.

563
00:21:06,690 --> 00:21:07,009
And,

564
00:21:07,490 --> 00:21:08,230
so you're

565
00:21:08,609 --> 00:21:11,509
you're going there, very exciting, to this conference,

566
00:21:12,049 --> 00:21:13,190
that's been organized

567
00:21:13,569 --> 00:21:14,309
in Helgoland

568
00:21:14,609 --> 00:21:15,910
to commemorate this.

569
00:21:16,609 --> 00:21:18,690
But you're starting in Hamburg, is that right?

570
00:21:18,690 --> 00:21:20,150
Which I suppose is the nearest

571
00:21:20,674 --> 00:21:23,714
big city to Helgoland. So what's going to

572
00:21:23,714 --> 00:21:24,615
happen in Hamburg,

573
00:21:25,554 --> 00:21:27,335
the the preconference event?

574
00:21:27,875 --> 00:21:29,634
So on the Monday so it's the it's

575
00:21:29,634 --> 00:21:31,474
quite soon, coming up soon. So it's Monday,

576
00:21:31,474 --> 00:21:31,974
the,

577
00:21:32,914 --> 00:21:35,734
June 9. There's a preconference

578
00:21:36,490 --> 00:21:39,149
banquet dinner at a hotel in in Hamburg,

579
00:21:39,609 --> 00:21:41,609
and there are three speakers talking about the

580
00:21:41,609 --> 00:21:42,669
history of,

581
00:21:43,529 --> 00:21:45,450
the subject. And one of them is actually

582
00:21:45,450 --> 00:21:47,690
Phil Ball, Philip Ball, who's an old friend,

583
00:21:47,690 --> 00:21:50,250
dare I say, Physics World. Listeners may remember

584
00:21:50,250 --> 00:21:51,644
he's written quite a lot for us,

585
00:21:52,205 --> 00:21:54,045
and, he's a bit of an expert in

586
00:21:54,045 --> 00:21:55,424
the history of quantum mechanics.

587
00:21:56,445 --> 00:21:58,365
And he's one of those unusual journalists who's

588
00:21:58,365 --> 00:22:00,924
kind of reached almost, like, the status of

589
00:22:00,924 --> 00:22:02,924
a knowledgeable expert in this area. He's at

590
00:22:02,924 --> 00:22:05,404
that really a crossover between being a journalist,

591
00:22:05,404 --> 00:22:07,570
science journalist, and the sort of experts on

592
00:22:07,570 --> 00:22:09,170
this area. So he's doing one of the

593
00:22:09,170 --> 00:22:11,029
talks at the conference dinner

594
00:22:11,650 --> 00:22:13,809
on the Monday. And then the next day,

595
00:22:13,809 --> 00:22:16,609
we get this ferry, which takes about four

596
00:22:16,609 --> 00:22:18,789
hours to get. You go up the Elbe.

597
00:22:19,009 --> 00:22:20,769
That's right. Yeah. Because Hamburg is actually a

598
00:22:20,769 --> 00:22:22,464
long way from the sea. It is. It's

599
00:22:22,464 --> 00:22:24,085
on a big river called the Elbe.

600
00:22:24,384 --> 00:22:26,144
And then so you go out the Elbe,

601
00:22:26,144 --> 00:22:27,825
and then do you turn right? Or does

602
00:22:27,825 --> 00:22:29,684
it turn left? You turn

603
00:22:31,024 --> 00:22:32,944
up up. I'm sure I'm sure the captain

604
00:22:32,944 --> 00:22:34,565
will know which way to go to Helgoland.

605
00:22:34,784 --> 00:22:36,304
So the Elbe, it's a Hamburg is a

606
00:22:36,304 --> 00:22:38,930
seaport and very, you know, important for Germany,

607
00:22:38,930 --> 00:22:40,470
but, it's quite a way

608
00:22:40,850 --> 00:22:42,289
inland. And so you go up the Elbe

609
00:22:42,289 --> 00:22:44,690
and then turn right, I think, as you

610
00:22:44,690 --> 00:22:46,309
say, and then you get to Helgoland

611
00:22:46,610 --> 00:22:49,269
after about four hours. Right. And and Helgoland

612
00:22:49,410 --> 00:22:51,509
itself, we're we're talking about this yesterday.

613
00:22:51,944 --> 00:22:53,865
And you said it's it's about the same

614
00:22:53,865 --> 00:22:56,204
size as the Bristol suburb of Clifton,

615
00:22:56,825 --> 00:22:58,505
which is not very big. It's not very

616
00:22:58,505 --> 00:23:00,345
big. I think it's about there's about 1,500

617
00:23:00,345 --> 00:23:01,865
people live on it. So suddenly, at this

618
00:23:01,865 --> 00:23:04,284
conference, there are gonna be 300 physicists

619
00:23:05,190 --> 00:23:07,429
turning up. So the population will increase by,

620
00:23:07,909 --> 00:23:09,049
is that 20%?

621
00:23:10,149 --> 00:23:12,869
And, yes, about one it's about 1.7 kilometers

622
00:23:12,869 --> 00:23:14,549
long and maybe a kilometer wide. There's actually

623
00:23:14,549 --> 00:23:16,250
a second island next to it,

624
00:23:16,630 --> 00:23:17,849
so not very big.

625
00:23:18,984 --> 00:23:21,325
These days, it's a kind of holiday resort,

626
00:23:21,384 --> 00:23:22,764
and there are a lot of beach

627
00:23:23,384 --> 00:23:25,884
villas and cottages and that sort of thing.

628
00:23:25,944 --> 00:23:28,664
Right. So I suppose it hasn't changed much

629
00:23:28,664 --> 00:23:31,750
because Heisenberg was on holiday there. So,

630
00:23:32,470 --> 00:23:34,390
Well, there is that famous story that after

631
00:23:34,390 --> 00:23:36,390
the second World War, the British ally and

632
00:23:36,390 --> 00:23:39,130
the allies, they collected all their unexploded bombs

633
00:23:39,269 --> 00:23:41,589
and put them on Helgoland. Oh, dear. Practically

634
00:23:41,589 --> 00:23:42,730
blew the island up.

635
00:23:43,029 --> 00:23:45,029
So that didn't do much for tourism. No.

636
00:23:45,029 --> 00:23:47,954
So anything that is connected with where Heisenberg

637
00:23:48,014 --> 00:23:50,254
stayed doesn't exist anymore. All the all the

638
00:23:50,254 --> 00:23:52,595
housing was blown up. So there's no sort

639
00:23:53,214 --> 00:23:55,214
of this is the room that Heisenberg stayed

640
00:23:55,214 --> 00:23:56,835
in that you can see, I don't think.

641
00:23:57,134 --> 00:23:59,714
Okay. Although there is a, a little

642
00:24:00,839 --> 00:24:02,299
sculpture statue thing,

643
00:24:03,319 --> 00:24:04,960
in honor of Heisenberg, so I'll make sure

644
00:24:04,960 --> 00:24:06,039
I have a look at that. Oh, yeah.

645
00:24:06,039 --> 00:24:08,440
I'll get some pictures. Definitely. Yeah. And and

646
00:24:08,440 --> 00:24:11,259
one of the big worries about going is

647
00:24:12,679 --> 00:24:13,179
accommodation.

648
00:24:14,204 --> 00:24:14,444
And,

649
00:24:15,005 --> 00:24:16,684
I I think am I right in thinking

650
00:24:16,684 --> 00:24:19,744
that you've you've sort of got a somebody

651
00:24:19,884 --> 00:24:22,365
probably canceled and you've got a last minute

652
00:24:22,365 --> 00:24:22,865
booking,

653
00:24:23,644 --> 00:24:25,404
so you're actually lucky enough to be able

654
00:24:25,404 --> 00:24:26,944
to go out to Halgo Land,

655
00:24:27,619 --> 00:24:30,180
where I'm guessing accommodation is pretty scarce. Yeah.

656
00:24:30,180 --> 00:24:32,019
There was instructions for anyone who wanted to

657
00:24:32,019 --> 00:24:33,539
go to, you might have to camp on

658
00:24:33,539 --> 00:24:34,119
the beach.

659
00:24:34,900 --> 00:24:37,700
I didn't really fancy doing that. And, luckily,

660
00:24:37,700 --> 00:24:38,600
there is a

661
00:24:39,795 --> 00:24:41,394
a, yeah, a place that I'll be staying

662
00:24:41,394 --> 00:24:43,634
in, which is very, very fortunate. But, yeah,

663
00:24:43,634 --> 00:24:44,934
all the hotels are booked

664
00:24:45,235 --> 00:24:47,414
out, have been for quite some time,

665
00:24:47,795 --> 00:24:50,035
like I say, with these 300 physicists turning

666
00:24:50,035 --> 00:24:51,955
up. So, yeah, it should be, and then,

667
00:24:51,955 --> 00:24:53,980
yeah, it's four days on the island. Yeah.

668
00:24:53,980 --> 00:24:55,980
And then come back to Hamburg. So it's

669
00:24:55,980 --> 00:24:57,440
a really unusual event,

670
00:24:57,819 --> 00:24:59,339
and there are some, you know, big big

671
00:24:59,339 --> 00:25:01,099
names going on. Am I am I right

672
00:25:01,099 --> 00:25:03,419
in thinking speaking of big names that Bob

673
00:25:03,419 --> 00:25:03,919
Kreese,

674
00:25:05,349 --> 00:25:05,849
longtime

675
00:25:06,445 --> 00:25:09,484
Physics World, contributor. Is he is he speaking

676
00:25:09,484 --> 00:25:11,325
there? I know he's written about how Golang

677
00:25:11,325 --> 00:25:11,825
Forest.

678
00:25:12,285 --> 00:25:14,525
He no. He is not going, but there

679
00:25:14,525 --> 00:25:18,125
are, some eminent people going, including I think

680
00:25:18,125 --> 00:25:19,265
I've counted four

681
00:25:19,990 --> 00:25:21,049
Nobel Prize winners,

682
00:25:22,710 --> 00:25:24,230
and I think all the Nobel Prize winners

683
00:25:24,230 --> 00:25:26,230
get must get tons of invitations, but there

684
00:25:26,230 --> 00:25:27,929
are four on the list there. Mhmm.

685
00:25:28,390 --> 00:25:29,210
Serge Haroche,

686
00:25:29,509 --> 00:25:30,409
Anton Sailinger,

687
00:25:31,109 --> 00:25:33,369
David Wineland, and Alan Aspect.

688
00:25:33,704 --> 00:25:36,184
Wow. So so some pretty strong connections to

689
00:25:36,184 --> 00:25:38,585
quantum physics there as well. Yeah. And then

690
00:25:38,585 --> 00:25:40,345
the rest of the people is it is

691
00:25:40,345 --> 00:25:41,944
a kind of who's who. I mentioned Phil

692
00:25:41,944 --> 00:25:44,265
Ball. There's people like Charles Bennett who came

693
00:25:44,265 --> 00:25:45,644
up with one of the algorithms.

694
00:25:47,789 --> 00:25:49,329
Michelle Simmons from Australia,

695
00:25:50,029 --> 00:25:50,849
Carla Ravelli,

696
00:25:52,109 --> 00:25:54,829
Michelle Lukin who won the Yeah. Yeah. Our

697
00:25:54,829 --> 00:25:57,230
favorite is on the podcast Exactly. Not too

698
00:25:57,230 --> 00:26:00,349
long ago. Yeah. And there's also Elisa Krill

699
00:26:00,349 --> 00:26:02,505
who's appearing in, Physics World.

700
00:26:03,545 --> 00:26:06,105
Oh, that's right. Yeah. She's a philosopher. Yeah.

701
00:26:06,105 --> 00:26:07,785
So so there will be a philosopher. It

702
00:26:07,785 --> 00:26:10,025
won't be Bob. Yeah. Not him. Right. There'll

703
00:26:10,025 --> 00:26:11,644
be a New York based philosopher.

704
00:26:12,505 --> 00:26:14,744
That's what you need at every conference. Yeah.

705
00:26:14,744 --> 00:26:16,678
Right. So, So, yeah, it's, you know, it's

706
00:26:16,678 --> 00:26:18,726
a real who's who. And there's other people

707
00:26:18,726 --> 00:26:21,849
like John Preskill Oh, right. Yeah. Sandhu Pippescu

708
00:26:21,910 --> 00:26:24,309
from the University of Bristol, Janeway Pan is

709
00:26:24,309 --> 00:26:24,809
invited,

710
00:26:25,509 --> 00:26:26,490
Nicholas Guissaint

711
00:26:27,109 --> 00:26:28,009
from Geneva,

712
00:26:29,029 --> 00:26:29,930
Bill Unruh,

713
00:26:30,295 --> 00:26:32,315
Canadian Yeah. Yeah. Person.

714
00:26:32,855 --> 00:26:33,755
Peter Zola.

715
00:26:35,095 --> 00:26:36,454
You know, if you're if you're into your

716
00:26:36,454 --> 00:26:38,535
quantum physics, this list of people I'm just

717
00:26:38,535 --> 00:26:40,335
looking at So it's a who's who, definitely.

718
00:26:40,695 --> 00:26:43,095
Pretty, yeah, you know, some big big shots,

719
00:26:43,095 --> 00:26:44,634
dare I say. Big big cheeses.

720
00:26:44,934 --> 00:26:47,630
Right. Okay. Well, that's that's great. And, you

721
00:26:47,630 --> 00:26:49,710
know, I mean, normally, I would say try

722
00:26:49,710 --> 00:26:51,950
to make it try to go there, dear

723
00:26:51,950 --> 00:26:54,190
listener, yourself, but I think unless you wanna

724
00:26:54,190 --> 00:26:55,329
camp out on the beach.

725
00:26:55,789 --> 00:26:58,190
And, and we have had some lovely weather

726
00:26:58,190 --> 00:27:00,345
recently, but, you know, it is in the

727
00:27:00,345 --> 00:27:01,164
North Sea,

728
00:27:01,785 --> 00:27:03,704
Northern Germany, so it could be a bit

729
00:27:03,704 --> 00:27:04,605
a bit chilly.

730
00:27:04,984 --> 00:27:06,105
Right. And,

731
00:27:06,585 --> 00:27:08,105
I mean, we have we have been doing

732
00:27:08,105 --> 00:27:10,184
lots of coverage of the International Year of

733
00:27:10,184 --> 00:27:11,565
Quantum Science and Technology

734
00:27:12,130 --> 00:27:13,349
in physics world.

735
00:27:13,730 --> 00:27:16,929
And, one thing that we've, that we've published

736
00:27:16,929 --> 00:27:18,769
very recently is a,

737
00:27:19,650 --> 00:27:20,869
a quantum briefing,

738
00:27:21,250 --> 00:27:23,990
which is chock full of some fantastic articles

739
00:27:24,690 --> 00:27:25,190
about,

740
00:27:25,809 --> 00:27:26,869
quantum physics.

741
00:27:27,375 --> 00:27:29,855
And it it has some flash fiction in

742
00:27:29,855 --> 00:27:31,855
it as well. It's a short story by,

743
00:27:32,414 --> 00:27:35,234
Kevlin Henney, who is a Bristol based, author

744
00:27:35,375 --> 00:27:36,914
amongst many other things.

745
00:27:37,615 --> 00:27:40,434
And he's he's looked at this famous voyage

746
00:27:40,575 --> 00:27:42,869
that, Heisenberg made to Helgoland,

747
00:27:43,170 --> 00:27:45,109
and he's come up with an alternative

748
00:27:46,609 --> 00:27:47,589
universe in which,

749
00:27:47,970 --> 00:27:49,670
Heisenberg didn't go there.

750
00:27:50,450 --> 00:27:52,369
And, you know, I suppose in in the

751
00:27:52,369 --> 00:27:53,430
spirit of the multiverse,

752
00:27:54,224 --> 00:27:55,984
has written about that. So can can you

753
00:27:55,984 --> 00:27:58,545
give us just a little preview of that

754
00:27:58,545 --> 00:28:01,184
story? Obviously, we want people to go and

755
00:28:01,184 --> 00:28:04,305
and read it. But, what what's Kevlin's premise

756
00:28:04,305 --> 00:28:04,964
on that?

757
00:28:05,505 --> 00:28:07,759
So so Kevlin is someone who is a

758
00:28:07,759 --> 00:28:09,920
physicist by training but works in the IT

759
00:28:09,920 --> 00:28:11,599
sector. And he was actually on our Physics

760
00:28:11,599 --> 00:28:13,279
World Stories podcast, so you can find out

761
00:28:13,279 --> 00:28:14,000
more from,

762
00:28:15,039 --> 00:28:17,140
last month. But, yeah, he

763
00:28:18,394 --> 00:28:21,115
is enjoys writing flash fiction, so he came

764
00:28:21,115 --> 00:28:22,514
up with this idea. I can't remember who

765
00:28:22,514 --> 00:28:24,095
it was, whether it was me or Tushner,

766
00:28:24,154 --> 00:28:26,234
our colleague, or him. This idea of an

767
00:28:26,234 --> 00:28:29,034
alternative universe where if Heisenberg hadn't been allowed

768
00:28:29,034 --> 00:28:30,414
to go to Helgorand

769
00:28:30,714 --> 00:28:32,335
and was had to stay in Gottingen,

770
00:28:33,130 --> 00:28:36,250
would that great event of discovering quantum mechanics

771
00:28:36,250 --> 00:28:38,089
have happened? So what he's he took took

772
00:28:38,089 --> 00:28:39,609
the idea and he's written it as a

773
00:28:39,609 --> 00:28:40,109
diary.

774
00:28:40,490 --> 00:28:42,490
So on the left hand side, he's got

775
00:28:42,490 --> 00:28:44,569
a diary, an imagined diary of what he'll

776
00:28:45,210 --> 00:28:46,190
Heisenberg did in Helgoland

777
00:28:46,595 --> 00:28:49,154
day by day. And on the right, he's

778
00:28:49,154 --> 00:28:51,555
kind of written a parallel diary of him

779
00:28:51,555 --> 00:28:54,195
staying at home and imagining him being frustrated

780
00:28:54,195 --> 00:28:55,575
and not being able to go.

781
00:28:56,355 --> 00:28:58,375
I did email Phil Ball and mention

782
00:28:58,674 --> 00:29:00,434
this to him, and he did actually say

783
00:29:00,434 --> 00:29:02,309
that he was interested in this idea of

784
00:29:02,309 --> 00:29:04,470
what we've done, but actually, he slightly poured

785
00:29:04,470 --> 00:29:06,390
cold water on it. He kind of thinks

786
00:29:06,390 --> 00:29:08,329
even if Heisenberg had never gone to Helgoland,

787
00:29:09,109 --> 00:29:11,029
he probably would have done this work anyway,

788
00:29:11,029 --> 00:29:12,009
just not on Helgoland.

789
00:29:12,470 --> 00:29:13,690
So it wasn't the magical

790
00:29:13,990 --> 00:29:15,930
Well hole in free sea air

791
00:29:16,294 --> 00:29:18,214
of Helgoland that Well, I think that's what

792
00:29:18,214 --> 00:29:19,654
he was implying in the email that he

793
00:29:19,654 --> 00:29:21,414
sent me that this would've it would've happened

794
00:29:21,414 --> 00:29:23,255
anyway. It would've been maybe would've been somewhere

795
00:29:23,255 --> 00:29:24,794
else or maybe a while later.

796
00:29:26,375 --> 00:29:27,894
But, yeah, it's a great little idea that

797
00:29:27,894 --> 00:29:29,320
he came up with of this. And so

798
00:29:29,320 --> 00:29:31,559
we've imagined it as if as if Kevlin

799
00:29:31,559 --> 00:29:33,640
Henney has discovered these notebooks. I mean, there

800
00:29:33,640 --> 00:29:35,420
there are no notebooks, but we've we've

801
00:29:35,799 --> 00:29:38,359
we've in the article, we've we've, laid it

802
00:29:38,359 --> 00:29:40,299
out as if it's a notebook.

803
00:29:40,920 --> 00:29:43,115
So it looks it looks quite realistic. It

804
00:29:43,115 --> 00:29:44,954
looks quite fun. So so, yeah, a clever

805
00:29:44,954 --> 00:29:47,134
little idea and, just a bit of fun,

806
00:29:48,075 --> 00:29:49,214
to sort of twist

807
00:29:50,394 --> 00:29:52,414
on old history, I think it's called.

808
00:29:52,954 --> 00:29:54,961
So, yeah, keep an eye out for that.

809
00:29:54,961 --> 00:29:57,574
Yeah. And and that is it's it's available

810
00:29:57,574 --> 00:29:59,897
for reading. The the quantum briefing can be

811
00:29:59,897 --> 00:30:02,220
found on the Physics World website, and I'll

812
00:30:02,220 --> 00:30:05,123
put an a link to it, in the

813
00:30:05,123 --> 00:30:07,965
notes for this podcast. It also, has an

814
00:30:07,965 --> 00:30:10,525
article by Margaret, a feature length article by

815
00:30:10,525 --> 00:30:11,025
Margaret

816
00:30:11,404 --> 00:30:13,585
about the quantum Zeno effect,

817
00:30:14,045 --> 00:30:14,605
which is,

818
00:30:15,164 --> 00:30:16,384
a sort of a fascinating

819
00:30:17,085 --> 00:30:18,144
quantum thing.

820
00:30:18,630 --> 00:30:21,269
And that that's actually the first quantum briefing,

821
00:30:21,269 --> 00:30:23,210
isn't it? There's there's gonna be a second

822
00:30:23,829 --> 00:30:26,230
quantum briefing that's going to be Not not

823
00:30:26,230 --> 00:30:28,070
quite a second we're gonna update this one

824
00:30:28,070 --> 00:30:29,210
with some extra articles.

825
00:30:29,990 --> 00:30:31,820
So this is a a digital magazine that

826
00:30:32,070 --> 00:30:34,125
so it's quite ease well, relatively easy to

827
00:30:34,125 --> 00:30:36,144
add in extra stuff. Right. Okay.

828
00:30:36,845 --> 00:30:38,764
There there were there are some limited printed

829
00:30:38,764 --> 00:30:40,524
copies in fact. We I'm gonna take a

830
00:30:40,524 --> 00:30:41,024
hundred

831
00:30:41,325 --> 00:30:43,404
in my suitcase. That's a hell go land.

832
00:30:43,404 --> 00:30:45,244
So anyone anyone listening, you know, get your

833
00:30:45,244 --> 00:30:47,005
hands on those. I'll be wandering around with

834
00:30:47,005 --> 00:30:49,380
these boxes with my suitcase trundling around the

835
00:30:49,380 --> 00:30:50,679
island, handing them out.

836
00:30:51,460 --> 00:30:53,220
But yeah. And also, yeah, the before we

837
00:30:53,220 --> 00:30:55,380
forget, there's the really great cover that we've

838
00:30:55,380 --> 00:30:56,099
got for it,

839
00:30:56,819 --> 00:30:58,179
which I know you were gonna come on

840
00:30:58,179 --> 00:30:59,240
to, which is by

841
00:31:00,964 --> 00:31:01,865
Tushner commissioned

842
00:31:02,244 --> 00:31:05,684
Felicity Inkpen, who's a scientist and artist who

843
00:31:05,684 --> 00:31:07,545
used to work So an artist called Inkpen.

844
00:31:07,765 --> 00:31:09,305
What what's that called? Nominative

845
00:31:10,005 --> 00:31:10,505
determinism?

846
00:31:10,884 --> 00:31:12,404
I think so. Yeah. Mind me out that

847
00:31:12,404 --> 00:31:14,244
wrong. Felicity. Yeah. It is a lovely it

848
00:31:14,244 --> 00:31:15,384
is a lovely cover.

849
00:31:15,710 --> 00:31:17,650
So what she's done is she

850
00:31:18,269 --> 00:31:20,430
it's called the the the painting is called

851
00:31:20,430 --> 00:31:20,930
Cubitt's

852
00:31:21,710 --> 00:31:22,210
Duality.

853
00:31:23,069 --> 00:31:25,150
So she it's a sort of, what she

854
00:31:25,150 --> 00:31:27,170
did is she took a tank of water

855
00:31:27,549 --> 00:31:30,075
and poured some colored dyes in and took

856
00:31:30,075 --> 00:31:32,894
lots of photographs and inspired from those pictures.

857
00:31:33,274 --> 00:31:35,755
She then painted an oil painting, and it

858
00:31:35,755 --> 00:31:36,974
kind of meant to symbolize

859
00:31:37,755 --> 00:31:39,054
wave particle duality.

860
00:31:40,154 --> 00:31:41,595
And we did that for the cover because

861
00:31:41,595 --> 00:31:43,274
I think we wanted something a bit different

862
00:31:43,274 --> 00:31:45,529
that's special for us and not just the

863
00:31:45,529 --> 00:31:46,029
usual

864
00:31:46,650 --> 00:31:48,569
standard stock pictures that,

865
00:31:49,529 --> 00:31:52,170
wouldn't perhaps have done the content justice. Yeah.

866
00:31:52,170 --> 00:31:54,170
Yeah. No. It it it really looks nice.

867
00:31:54,170 --> 00:31:57,404
Yeah. So, yeah, definitely look out for that.

868
00:31:57,565 --> 00:31:59,265
And if you happen to be on Helgoland,

869
00:32:00,045 --> 00:32:01,904
ask Matin for a for a copy.

870
00:32:02,205 --> 00:32:03,744
Now, Hamish, before we finish,

871
00:32:04,924 --> 00:32:07,404
you have been writing something quite interesting, a

872
00:32:07,404 --> 00:32:08,785
research update about

873
00:32:09,085 --> 00:32:09,585
neutrons

874
00:32:10,549 --> 00:32:13,750
and, which obviously these are subatomic particles without

875
00:32:13,750 --> 00:32:14,250
charge,

876
00:32:14,789 --> 00:32:16,470
but using it in a very unusual way

877
00:32:16,470 --> 00:32:18,490
to differentiate between counterfeit

878
00:32:19,429 --> 00:32:20,809
and genuine antique

879
00:32:21,109 --> 00:32:23,585
coins. So what are these coins, Hamish? Well,

880
00:32:23,585 --> 00:32:26,704
they're, they're Korean coins from the early nineteenth

881
00:32:26,704 --> 00:32:27,204
century.

882
00:32:27,664 --> 00:32:28,945
And, you know, if you if you're sort

883
00:32:28,945 --> 00:32:31,105
of familiar with old coins, they're that that

884
00:32:31,105 --> 00:32:32,085
sort of classic

885
00:32:32,625 --> 00:32:35,184
round coin with a square hole in the

886
00:32:35,184 --> 00:32:37,269
middle of it. You know, you that seems

887
00:32:37,269 --> 00:32:39,029
to be a common Didn't the Danish used

888
00:32:39,029 --> 00:32:41,109
to have coins like that? Oh, maybe they

889
00:32:41,109 --> 00:32:43,190
did. Maybe you'll find some on Helgoland Oh,

890
00:32:43,190 --> 00:32:43,669
yeah.

891
00:32:44,150 --> 00:32:45,750
Washing up on the beach. But the these

892
00:32:45,750 --> 00:32:47,049
are from Korea.

893
00:32:47,750 --> 00:32:49,369
And, yeah, some researchers

894
00:32:49,670 --> 00:32:52,089
in Korea and also in The US

895
00:32:52,555 --> 00:32:53,355
have used,

896
00:32:53,674 --> 00:32:55,615
a a a sort of a a novel

897
00:32:56,555 --> 00:32:59,914
technique using neutron scattering to tell the fake

898
00:32:59,914 --> 00:33:02,414
ones from the real ones. Yeah.

899
00:33:03,434 --> 00:33:05,934
And, well, how did they do that? Well,

900
00:33:06,910 --> 00:33:08,430
the the the they used two techniques. But

901
00:33:08,430 --> 00:33:10,109
the the technique that I found,

902
00:33:10,590 --> 00:33:11,490
most interesting

903
00:33:12,109 --> 00:33:12,609
is,

904
00:33:13,309 --> 00:33:15,809
they used the presence of hydrogen

905
00:33:16,269 --> 00:33:17,090
in the coins,

906
00:33:18,109 --> 00:33:19,650
to tell the difference between,

907
00:33:19,950 --> 00:33:22,545
an a genuine antique one and a sort

908
00:33:22,545 --> 00:33:25,424
of a more modern fake one that has

909
00:33:25,424 --> 00:33:26,164
just been

910
00:33:26,785 --> 00:33:29,125
chemically treated to look old. So the fakes,

911
00:33:29,345 --> 00:33:31,265
modern fakes pretending to look old. They weren't

912
00:33:31,265 --> 00:33:32,785
fakes from the time. Yeah. Yeah. They're yeah.

913
00:33:32,785 --> 00:33:34,704
They're modern fakes. They were people trying to

914
00:33:34,704 --> 00:33:35,765
sort of, Exactly.

915
00:33:36,660 --> 00:33:38,740
No. No. No. No. No. No. No. These

916
00:33:38,740 --> 00:33:40,740
are modern fakes. I suppose these coins are

917
00:33:40,740 --> 00:33:41,240
collectible.

918
00:33:41,700 --> 00:33:43,700
And it's it's interest I I found it

919
00:33:43,700 --> 00:33:45,720
interesting. I do have love for neutrons.

920
00:33:46,180 --> 00:33:48,580
And I I found it interesting because it's

921
00:33:48,580 --> 00:33:50,580
sort of a twist on how neutrons are

922
00:33:50,580 --> 00:33:51,640
normally used

923
00:33:52,075 --> 00:33:53,295
to study materials.

924
00:33:54,475 --> 00:33:56,234
Usually, you take a a beam and you

925
00:33:56,234 --> 00:33:59,535
scatter them from a sample, and the resulting

926
00:33:59,595 --> 00:34:01,375
diffraction pattern tells you

927
00:34:01,674 --> 00:34:03,914
about the structure of the sample. That's a

928
00:34:03,914 --> 00:34:04,654
very straightforward

929
00:34:05,500 --> 00:34:07,819
use of neutrons and Nobel prizes have been

930
00:34:07,819 --> 00:34:08,800
won for developing,

931
00:34:09,900 --> 00:34:11,119
those sort of techniques.

932
00:34:11,820 --> 00:34:13,980
But the thing about hydrogen is that it's

933
00:34:13,980 --> 00:34:16,400
a bad thing when it comes to neutrons.

934
00:34:16,780 --> 00:34:19,679
Hydrogen messes up this process because the proton

935
00:34:20,065 --> 00:34:22,405
that, you know, the nucleus within a hydrogen,

936
00:34:23,425 --> 00:34:25,045
is a very good incoherent

937
00:34:25,505 --> 00:34:29,204
scatterer of neutrons. And essentially, that means that,

938
00:34:29,824 --> 00:34:32,005
if there's lots of hydrogen in your sample,

939
00:34:32,065 --> 00:34:35,204
it blurs these patterns that you're looking for.

940
00:34:35,699 --> 00:34:36,199
And,

941
00:34:37,219 --> 00:34:39,859
in order to do neutron scattering experiments on

942
00:34:39,859 --> 00:34:41,400
hydrogen rich samples,

943
00:34:41,699 --> 00:34:44,280
researchers actually replace the hydrogen

944
00:34:44,739 --> 00:34:45,719
with deuterium.

945
00:34:46,019 --> 00:34:47,239
They call this deuteration.

946
00:34:48,824 --> 00:34:51,485
And they do that because deuterium, which is,

947
00:34:52,025 --> 00:34:55,164
a proton with a neutron, so helium hydrogen

948
00:34:55,224 --> 00:34:55,724
two,

949
00:34:56,425 --> 00:34:58,125
is not a good incoherent

950
00:34:58,425 --> 00:35:00,585
scatterer. So in the world of neutrons, you

951
00:35:00,585 --> 00:35:01,965
want to avoid hydrogen,

952
00:35:02,809 --> 00:35:03,789
at all cost.

953
00:35:04,730 --> 00:35:07,289
But in this new work, which was led

954
00:35:07,289 --> 00:35:08,510
by Youngju Kim

955
00:35:08,809 --> 00:35:11,929
and Daniel Hussey at, NIST, at the National

956
00:35:11,929 --> 00:35:14,684
Institute of Standards and Technology, and

957
00:35:15,085 --> 00:35:16,224
presence of hydrogen

958
00:35:16,525 --> 00:35:17,344
in coins

959
00:35:17,724 --> 00:35:20,204
was detected by, you know, sort of looking

960
00:35:20,204 --> 00:35:20,704
for

961
00:35:21,005 --> 00:35:22,144
this incoherent

962
00:35:22,445 --> 00:35:23,744
scattering of neutrons.

963
00:35:25,485 --> 00:35:26,925
So how did that work? I guess the

964
00:35:26,925 --> 00:35:29,085
neutrons travel through the coins, do they? And

965
00:35:29,085 --> 00:35:32,179
maybe the does the hydrogen block the neutrons

966
00:35:32,239 --> 00:35:33,119
more than the,

967
00:35:33,519 --> 00:35:35,940
the other ones? Yeah. That's exactly what happens.

968
00:35:36,719 --> 00:35:38,960
Beauty of neutrons is that they can travel

969
00:35:38,960 --> 00:35:41,300
through a lot of materials very easily.

970
00:35:41,840 --> 00:35:42,559
And so,

971
00:35:42,960 --> 00:35:45,039
the the the neutrons can travel through the

972
00:35:45,039 --> 00:35:45,539
metal

973
00:35:45,945 --> 00:35:48,585
of the coin very easily, but they're actually

974
00:35:48,585 --> 00:35:50,684
blocked, as you say, by by hydrogen.

975
00:35:51,224 --> 00:35:53,965
And this hydrogen is in inclusions

976
00:35:54,265 --> 00:35:55,724
of hydrogen rich

977
00:35:56,105 --> 00:35:58,364
materials that are created by corrosion.

978
00:35:59,199 --> 00:36:01,199
And it turns out that because the real

979
00:36:01,199 --> 00:36:02,420
coins are older,

980
00:36:03,119 --> 00:36:05,140
they have much deeper corrosion

981
00:36:05,599 --> 00:36:06,099
inclusions

982
00:36:06,800 --> 00:36:07,699
than the fakes.

983
00:36:08,000 --> 00:36:10,340
And though that much deeper corrosion

984
00:36:10,719 --> 00:36:11,840
is what,

985
00:36:12,565 --> 00:36:13,385
is revealed

986
00:36:13,765 --> 00:36:16,724
by the, by the neutron experiment. So even

987
00:36:16,724 --> 00:36:19,125
though the fakes have been corroded to look

988
00:36:19,125 --> 00:36:21,864
old, they they don't have these deep inclusions

989
00:36:21,925 --> 00:36:23,224
because that takes time.

990
00:36:23,765 --> 00:36:25,925
And, Oh, I see. So they actually corrode

991
00:36:25,925 --> 00:36:27,289
the fakes to make them look old, but

992
00:36:27,530 --> 00:36:29,849
Exactly. The real the real stuff has deeper.

993
00:36:29,849 --> 00:36:32,889
Has deeper deeper inclusions. Yeah. That's right. So

994
00:36:32,889 --> 00:36:34,250
that Hang on. Now they know what to

995
00:36:34,250 --> 00:36:36,170
do. So they're Well, yeah. That's the problem

996
00:36:36,170 --> 00:36:37,530
is that if, you know, if you if

997
00:36:37,530 --> 00:36:39,070
you make fake Korean coins

998
00:36:39,444 --> 00:36:40,105
and you

999
00:36:40,405 --> 00:36:43,364
read missed press releases or physics world, you're

1000
00:36:43,364 --> 00:36:44,744
you're you're on your way.

1001
00:36:45,125 --> 00:36:46,804
And Hang on. Is there a big market

1002
00:36:46,804 --> 00:36:48,804
for these fake coins? Is that Well, I

1003
00:36:48,804 --> 00:36:51,125
would imagine. I mean, you know, people do

1004
00:36:51,125 --> 00:36:52,424
like to collect coins.

1005
00:36:52,724 --> 00:36:53,704
So yeah.

1006
00:36:54,579 --> 00:36:56,760
Yeah. And and they they also used

1007
00:36:57,059 --> 00:36:59,780
another technique to look at at these coins,

1008
00:36:59,780 --> 00:37:01,400
and that's a a sophisticated

1009
00:37:01,699 --> 00:37:04,440
version of something called small angle scattering.

1010
00:37:04,900 --> 00:37:07,380
And small angle scattering is something that allows

1011
00:37:07,380 --> 00:37:08,519
you to look at

1012
00:37:08,894 --> 00:37:10,114
fairly big things

1013
00:37:10,414 --> 00:37:12,894
in a sample, so not the atomic structure,

1014
00:37:12,894 --> 00:37:14,515
but bigger structures

1015
00:37:14,894 --> 00:37:15,875
within a sample.

1016
00:37:16,414 --> 00:37:18,414
And what they did is they used the

1017
00:37:18,414 --> 00:37:19,554
small angle scattering

1018
00:37:19,934 --> 00:37:22,434
to look at tiny pores on the surfaces

1019
00:37:23,019 --> 00:37:25,579
of the coins. And these pores occur as

1020
00:37:25,579 --> 00:37:27,820
the coins age, you know, they they interact

1021
00:37:27,820 --> 00:37:28,720
with their environment.

1022
00:37:29,099 --> 00:37:31,260
Material is removed from the surface of the

1023
00:37:31,260 --> 00:37:31,760
coin.

1024
00:37:32,619 --> 00:37:33,519
And counterintuitively,

1025
00:37:34,140 --> 00:37:35,920
what they found is that the genuine

1026
00:37:36,539 --> 00:37:37,360
older coins

1027
00:37:37,815 --> 00:37:39,114
had smaller pores

1028
00:37:39,734 --> 00:37:42,214
than the fake coins. Fake coins had pores,

1029
00:37:42,214 --> 00:37:43,755
but the pores were much bigger.

1030
00:37:44,375 --> 00:37:46,375
Now you might not expect that to happen,

1031
00:37:46,375 --> 00:37:46,875
but

1032
00:37:47,734 --> 00:37:50,375
they believe the researchers believe that the reason

1033
00:37:50,375 --> 00:37:51,835
this happened is that

1034
00:37:52,349 --> 00:37:54,750
because the old coins have been buried actually,

1035
00:37:54,750 --> 00:37:56,530
I think in this case, they've been underwater

1036
00:37:57,150 --> 00:37:58,289
for a long time.

1037
00:38:00,269 --> 00:38:02,110
The the pores are produced, but then they

1038
00:38:02,110 --> 00:38:03,410
start to fill in

1039
00:38:03,869 --> 00:38:05,809
through other chemical processes.

1040
00:38:06,215 --> 00:38:07,275
And so the genuine

1041
00:38:07,655 --> 00:38:08,474
old coins

1042
00:38:09,175 --> 00:38:09,675
have,

1043
00:38:10,295 --> 00:38:11,675
have much smaller pores

1044
00:38:11,974 --> 00:38:13,735
than the new coins, which have been sort

1045
00:38:13,735 --> 00:38:14,394
of artificially

1046
00:38:15,494 --> 00:38:16,795
corroded or aged.

1047
00:38:17,094 --> 00:38:19,094
And so in in a sense, the neutrons

1048
00:38:19,094 --> 00:38:19,755
have revealed

1049
00:38:20,135 --> 00:38:20,635
two

1050
00:38:21,094 --> 00:38:21,594
signatures

1051
00:38:22,210 --> 00:38:23,349
of old coins.

1052
00:38:23,969 --> 00:38:24,849
And so now,

1053
00:38:25,250 --> 00:38:27,570
now these researchers are they're they're going back

1054
00:38:27,570 --> 00:38:29,670
and they're gonna look at a broader

1055
00:38:30,610 --> 00:38:33,329
sample of fake and real coins and and

1056
00:38:33,329 --> 00:38:35,954
and see if they can confirm this. But,

1057
00:38:36,195 --> 00:38:38,215
yeah, I thought this was a really interesting

1058
00:38:38,755 --> 00:38:40,375
use of neutron scattering.

1059
00:38:41,315 --> 00:38:43,155
You you I mean, you know, I I

1060
00:38:43,155 --> 00:38:44,994
I had the privilege of of working at

1061
00:38:44,994 --> 00:38:47,655
a a reactor where they did neutron scattering.

1062
00:38:47,760 --> 00:38:49,119
And, yeah, of course, you know, they were

1063
00:38:49,119 --> 00:38:52,079
looking at new magnetic materials and things like

1064
00:38:52,079 --> 00:38:54,960
that, but they're also very interested in,

1065
00:38:56,320 --> 00:38:58,099
you know, sort of industrial applications.

1066
00:38:59,039 --> 00:39:01,059
You know, they would look at bits of

1067
00:39:02,264 --> 00:39:04,444
a jet engine to look for

1068
00:39:05,144 --> 00:39:05,644
cracks

1069
00:39:06,105 --> 00:39:06,744
within the,

1070
00:39:07,704 --> 00:39:10,344
the turbine blades that are not evident from

1071
00:39:10,344 --> 00:39:11,005
the surface.

1072
00:39:11,304 --> 00:39:13,864
So, you know, neutron scattering is, you know,

1073
00:39:13,864 --> 00:39:16,424
there's lots of really interesting applications, and one

1074
00:39:16,424 --> 00:39:17,579
of them, I suppose, is

1075
00:39:17,980 --> 00:39:20,300
looking at, you know, antiquities and,

1076
00:39:20,860 --> 00:39:21,760
spotting fakes.

1077
00:39:22,619 --> 00:39:24,140
So yeah. But I was just trying to

1078
00:39:24,140 --> 00:39:25,820
imagine to to imagine if someone offers you

1079
00:39:25,820 --> 00:39:27,420
a fake Korean coin. You go, hang on

1080
00:39:27,420 --> 00:39:28,780
a minute. Let me just go down to

1081
00:39:28,780 --> 00:39:30,079
the, NIST in Colorado,

1082
00:39:30,695 --> 00:39:32,614
check check with these neutron people. Can can

1083
00:39:32,614 --> 00:39:34,454
I take my coin along to check it?

1084
00:39:34,454 --> 00:39:36,535
Yeah. Yeah. Yeah. Or or or will I

1085
00:39:36,614 --> 00:39:38,695
It's just in Maryland. Maryland. Or will I've

1086
00:39:38,695 --> 00:39:40,015
already bought it? And maybe I've already bought

1087
00:39:40,015 --> 00:39:41,255
it, and then I wasted my money. And

1088
00:39:41,255 --> 00:39:43,094
then I then I'm gonna be really disappointed

1089
00:39:43,094 --> 00:39:44,476
I'm gonna take it, and it works out

1090
00:39:44,476 --> 00:39:46,769
as Yeah. I mean, I think what these

1091
00:39:46,769 --> 00:39:49,250
researchers say in their papers that it's probably

1092
00:39:49,250 --> 00:39:52,710
more useful for people who do historical research.

1093
00:39:53,170 --> 00:39:53,670
Because,

1094
00:39:54,050 --> 00:39:55,750
you know, a lot of our understanding

1095
00:39:56,289 --> 00:39:59,329
of history comes from coins, and where coins

1096
00:39:59,329 --> 00:39:59,990
are found.

1097
00:40:00,965 --> 00:40:02,344
And so it'll allow,

1098
00:40:02,804 --> 00:40:03,304
historians

1099
00:40:04,005 --> 00:40:05,144
and I suppose archaeologists

1100
00:40:05,765 --> 00:40:06,585
to verify,

1101
00:40:07,844 --> 00:40:10,005
finds of coins and and and that sort

1102
00:40:10,005 --> 00:40:11,605
of thing. Yeah. So Do you know what?

1103
00:40:11,605 --> 00:40:12,965
I've been reminded of that feature we had.

1104
00:40:12,965 --> 00:40:14,585
Do you remember a few years ago about

1105
00:40:15,199 --> 00:40:16,739
studying Chinese porcelain

1106
00:40:17,359 --> 00:40:19,839
using optical microscopy to look for the inclusions

1107
00:40:19,839 --> 00:40:22,400
in the, glazing? Oh, right. Yeah. And that

1108
00:40:22,400 --> 00:40:25,440
again was for spotting fake fake Chinese vases,

1109
00:40:25,440 --> 00:40:27,119
which is a, you know, huge market for

1110
00:40:27,119 --> 00:40:28,019
that. Yeah.

1111
00:40:28,625 --> 00:40:30,464
Yeah. It is interesting. And I I suppose

1112
00:40:30,464 --> 00:40:32,164
at the end of the day, okay,

1113
00:40:32,625 --> 00:40:33,444
these counterfeiters,

1114
00:40:33,824 --> 00:40:34,804
they might know

1115
00:40:35,505 --> 00:40:38,304
that they need to put these inclusions in.

1116
00:40:38,304 --> 00:40:40,484
But unless they've got a neutral facility,

1117
00:40:41,585 --> 00:40:43,444
they won't know if they've done it properly.

1118
00:40:43,960 --> 00:40:46,119
So I suppose in principle, they could they

1119
00:40:46,119 --> 00:40:47,500
could improve their fakes.

1120
00:40:47,880 --> 00:40:48,280
But,

1121
00:40:48,760 --> 00:40:51,160
it it would be very difficult to, you

1122
00:40:51,160 --> 00:40:52,519
know, they might try to slip in a

1123
00:40:52,519 --> 00:40:53,500
research proposal

1124
00:40:55,239 --> 00:40:57,579
to, you know, to that mist reactor.

1125
00:40:57,960 --> 00:40:59,744
Hopefully, somebody would spot it.

1126
00:41:00,385 --> 00:41:03,345
Yeah. So that's neutrons and fake coins. And

1127
00:41:03,345 --> 00:41:05,265
you can find find out more about this

1128
00:41:05,265 --> 00:41:07,184
on the Physics World website. Just look for

1129
00:41:07,184 --> 00:41:07,845
the headline,

1130
00:41:08,305 --> 00:41:08,805
neutrons

1131
00:41:09,265 --> 00:41:09,765
differentiate

1132
00:41:10,224 --> 00:41:14,400
between real and fake antique coins. Thanks, Matin.

1133
00:41:14,780 --> 00:41:15,599
Thanks, Hamish.

1134
00:41:23,260 --> 00:41:25,019
I'm afraid that's all the time we have

1135
00:41:25,019 --> 00:41:26,320
for this week's podcast.

1136
00:41:26,735 --> 00:41:29,855
Thanks to Margaret Harris and Matin Durrani for

1137
00:41:29,855 --> 00:41:30,994
joining me today.

1138
00:41:31,375 --> 00:41:34,175
And a special thanks to our producer, Fred

1139
00:41:34,175 --> 00:41:34,675
Ailes.

1140
00:41:35,215 --> 00:41:37,155
We'll be back again next week.