Exploring this year’s best physics research in our Top 10 Breakthroughs of 2025

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Hello. I'm Matin Durrani, and welcome to a

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very special edition of the Physics World weekly

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podcast,

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where we're going to be revealing the top

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10 breakthroughs in physics for 2025.

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Every year here at Physics World, we pick

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what we think have been the biggest breakthroughs

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over the last twelve months, and we've had

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chosen some amazing successes over the years that

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include the Higgs boson,

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gravitational waves, and the shadow around a black

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hole. With last year, the top prize going

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to work on quantum error correction at Google

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and elsewhere.

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So taking you through our choices for 2025,

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I'm joined by my colleagues Margaret Harris,

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Tammy Freeman, Michael Banks, and Hamish Johnson.

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The physics world breakthrough the year 2025

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is sponsored by Reports on Progress in Physics.

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Celebrating the most significant advances across the physical

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sciences,

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this award highlights discoveries that reshape our understanding

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of the universe and inspire future innovation.

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Reports on Progress in Physics is the leading

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journal for authoritative

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research,

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connecting researchers worldwide with cutting edge insights across

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every field of physics.

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From quantum technologies to astrophysics,

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it provides the depth and clarity that drive

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scientific progress.

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Search reports on progress in physics on your

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favorite browser to explore the ideas transforming science

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today.

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So let's get cracking on the top 10

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physics world breakthroughs in physics for 2025,

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which, just to remind you, we pick based

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on three

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criteria. So in addition to having been reported

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in physics world in 2025,

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our selections have to represent a significant advance

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in knowledge or understanding,

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be important for scientific progress and or development

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of real world applications,

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and be of general interest to Physics World

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readers.

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So we're gonna start with a bit of

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astronomy, with astronomers creating what they say is

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a weather map

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for a gas giant exoplanet.

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Now it's hard enough for trying to predict

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the weather here in on Earth, although I

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know it's been a pretty dry year in

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Bristol in the Southwest corner of England where

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we are. So this sounds pretty cool to

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me. Hamish, you're gonna explain this breakthrough for

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us.

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That's right, Matin. This this first, breakthrough is

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astronomy related breakthrough, and it has to do

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with exoplanets.

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Now it's only been thirty years since the

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first exoplanet,

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orbiting a star, that's a planet orbiting a

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star other than the sun, was discovered.

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And today, astronomers know of more than 6,000

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such objects.

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And this breakthrough, it's been made by Lisa

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Nortman

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at Germany's

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University

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of Gottingen

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and colleagues,

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and they've used the European

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Southern Observatory's

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Very Large Telescope

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to create what they're saying

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is the first weather map of an exoplanet.

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Now this exoplanet is a hot Jupiter.

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It's a gas giant called WASP

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one twenty seven b,

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and it orbits very near to its star.

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So this is not something that we have

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in a in in the solar system. It's

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a very sort of exotic

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thing as far as we we're concerned. And

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what Nortman and colleagues did is they studied

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the absorption

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spectrum of starlight that had passed through the

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exoplanet's

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atmosphere.

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And

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by, looking at the Doppler shift of this,

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transmission spectrum,

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they could deduce that the winds on WASP

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one twenty seven b can reach as as

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high as 33,000

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kilometers per hour,

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which is pretty fast. That's quick. It it

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it is. Yeah. Yeah. And and what's more,

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by looking at the, sort of, the distribution

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of of how,

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the light is Doppler shifted,

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they could create a rough weather map of

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the exoplanet. Now, it's important to say that

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they weren't actually able to look at different

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points

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on the exoplanet

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and say the weather is like this there.

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What they did is they they looked at

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this distribution

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and somehow used that information to

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infer what the weather was like from the

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pole down to the Equator

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and, back again to to the other pole.

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So they were able to conclude,

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along with looking at the winds, they were

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able to conclude

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that the exoplanet's poles are cooler

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than the rest of the exoplanet,

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where,

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temperatures can exceed,

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over a thousand degrees Celsius. So, again, a

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very strange place.

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Imagine Jupiter, but it's a thousand degrees Celsius,

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sort of a weird world.

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And they also, detected water vapor in the

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atmosphere,

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and that raises the possibility of very exotic

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forms of rain on the planet.

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So rain,

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other than

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how we know it, I suppose.

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And, you know, I think we picked this

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one. Really, there's lots of really fantastic exoplanet

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research out there, thousands that have been discovered.

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But this was

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a a a really interesting,

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example of how we can we can now

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actually see the atmosphere

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of these exoplanets

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using, you know, the very latest telescopes.

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So very hot, very windy, and exotic rain.

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I don't think I wanna live there. Thanks,

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Hamish. Now from exoplanets out in space down

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to our planet here on Earth, our next

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breakthrough through of the year is a fascinating

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study

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about using the phones we all carry around

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with us to create an early warning system

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for earthquakes

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or at least using Android phones. Michael, can

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you tell us about this breakthrough, which seems

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like a great example of citizen science? Yeah.

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So this is all about using mobile phones

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to detect earthquakes. So traditional

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earthquake early warning systems usually use networks of

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seismic sensors

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that rapidly detect earthquakes in areas close to

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the epicenter.

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They also issue warnings to, people also across

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the affected region.

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Yet the issue is that building such networks

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of bulky sensors, it's expensive,

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you know, and this means that many earthquake

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prone regions do not have them. So to

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get around this problem, researchers in The US

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utilized the accelerometer housed in millions of mobile

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phones worldwide

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to create an app based Android earthquake alert

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system.

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So testing the app between 2021 and 2024

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led to the detection of an average of

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312

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earthquakes a month with magnitudes ranging from 1.9

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to 7.8 on the Richter scale.

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But what is more, the app could also

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alert people in the area. So for earthquakes

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of magnitude 4.5

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or higher,

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the system sent so called take action alerts

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to users.

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It also delivered lesser be aware alerts to

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regions expected to experience a shaking intensity of

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three or four.

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So the team now aimed to build on

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this earthquake early warning system based on Android

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mobile phones by producing maps of ground shaking

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as well.

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And this could all help assist the emergency

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response services when an earthquake occurs.

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Thanks, Michael. So from communicating with mobiles to

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communicating via the cables that make up the

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Internet,

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which is the almost invisible technology that underpins

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modern life. Now it seems the researchers have

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developed a new kind of fiber that loses

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that lose less data

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as the signals get sent down them. Tammy,

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what's this one about?

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So optical fibers form the backbone of the

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Internet carrying light signals across the globe.

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But sunlight is always lost as it travels

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through the fiber, which means that these signals

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must be amplified every few dozen kilometers.

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Now amazingly, the performance of even the best

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fibers has remained largely unchanged for nearly four

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decades

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until now.

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Physicists at the University of Southampton

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have developed a new type of fiber that

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exhibits 35%

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less attenuation

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while transmitting signals faster than standard glass fibers,

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and they achieved this by replacing the glass

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core of a conventional fiber with air.

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To guide the light through this hollow core,

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it's surrounded by a microstructure

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of ultrathin glass membranes that reflect certain frequencies

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to trap the light and keep it moving

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through the fiber.

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So to test this design, the team, which

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also included researchers from Microsoft Azure Fiber,

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they measured the transmission through a full spool

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of fiber, then they cut it into shorter

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lengths and compared the results.

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And they found that their hollow fibers reduced

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the attenuation

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to just naught point naught nine one decibels

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per kilometer at fifteen fifty nanometers, which is

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a wavelength used for telecoms.

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And this means that long cables would need

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fewer amplifiers,

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lowering the costs and the energy use.

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The new hollow fiber also supports a higher

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bandwidth

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than a normal fiber,

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which means that a single strand can carry

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far more channels at once.

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And because the speed of light's faster in

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air than in glass, the data could travel

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the same distance up to 45%

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faster.

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Now Microsoft has begun testing the new fibers

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in real systems,

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installing segments in its network and sending live

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traffic through them.

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And these trials prove that the hollow core

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design works with existing telecoms equipment and opens

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the door to a gradual rollout of this

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new source of fiber.

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And as team leader Francesco Paletti suggests, one

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day, they could even replace existing undersea cables.

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So that's the first three of our physics

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world breakthroughs of the year for 2025

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done.

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Now next up is some cool condensed matter

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physics that's involved superfluidity

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spotted in molecular hydrogen for the first time.

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Now, Margaret, physicists are pretty familiar with superfluidity

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in helium three and helium four

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atoms, but now we're talking about molecules, aren't

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we?

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Yeah. We're talking about specifically about molecular hydrogen,

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which is the simplest and lightest of all

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molecules. You take one hydrogen atom, you take

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another hydrogen atom, you link them together.

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And theorists predicted that this molecular hydrogen would

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enter a superfluid state at a temperature between

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one to two Kelvin above absolute zero,

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which is pretty cold.

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But the real problem with that is that

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molecular hydrogen freezes at 13.8

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Kelvin, So, obviously, it's not going to be

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behaving like a superfluid if it's further than

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solid.

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00:10:42,629 --> 00:10:45,210
So before they could verify this prediction, Takamasa

277
00:10:45,350 --> 00:10:47,670
Momosa and colleagues at the University of British

278
00:10:47,670 --> 00:10:48,809
Columbia in Canada,

279
00:10:49,269 --> 00:10:50,790
they first had to develop a way to

280
00:10:50,790 --> 00:10:52,455
keep the hydrogen in a liquid state.

281
00:10:53,014 --> 00:10:55,095
And they did that by confining clusters of

282
00:10:55,095 --> 00:10:59,115
hydrogen molecules inside nanodroplets of helium and supercooling

283
00:10:59,254 --> 00:11:01,835
them to below their freezing point, which,

284
00:11:02,215 --> 00:11:03,735
I mean, I've never done it, but I

285
00:11:03,735 --> 00:11:06,134
imagine that isn't exactly easy. Certainly, it sounds

286
00:11:06,134 --> 00:11:07,434
like an impressive feat.

287
00:11:07,940 --> 00:11:10,259
And then once they've done that, they faced

288
00:11:10,259 --> 00:11:12,179
a further barrier, which was figure out how

289
00:11:12,179 --> 00:11:14,579
to detect whether the hydrogen was superfluid or

290
00:11:14,579 --> 00:11:15,079
not.

291
00:11:15,459 --> 00:11:17,459
And to do that, they stuck a methane

292
00:11:17,459 --> 00:11:19,799
molecule in with the cluster of hydrogen molecules

293
00:11:20,179 --> 00:11:21,399
and watched it rotate.

294
00:11:21,914 --> 00:11:24,495
And when it started to rotate without friction,

295
00:11:24,955 --> 00:11:26,495
they knew they'd seen superfluidity.

296
00:11:27,434 --> 00:11:29,274
Apparently, it took them nearly twenty years to

297
00:11:29,274 --> 00:11:31,034
sort of develop this experiment at this point,

298
00:11:31,034 --> 00:11:33,195
so this breakthrough was a long time coming.

299
00:11:33,195 --> 00:11:35,195
And it's a testament to the dedication and

300
00:11:35,195 --> 00:11:36,794
ingenuity of the team that they were able

301
00:11:36,794 --> 00:11:38,129
to do it at all. This is a

302
00:11:38,129 --> 00:11:40,549
real physicist experiment on my view at least.

303
00:11:41,329 --> 00:11:43,329
They now plan to study larger clusters of

304
00:11:43,329 --> 00:11:45,409
hydrogen with the aim of exploring the boundary

305
00:11:45,409 --> 00:11:48,549
between classical and quantum behavior in this system.

306
00:11:48,929 --> 00:11:51,250
So, I mean, they've seen superfluidity with 10

307
00:11:51,250 --> 00:11:52,725
hydrogen molecules. Great.

308
00:11:53,284 --> 00:11:54,964
Can I see it with a 100? What

309
00:11:54,964 --> 00:11:57,365
about a thousand or a million? We don't

310
00:11:57,365 --> 00:11:59,204
know the answer, but it'll be really exciting

311
00:11:59,204 --> 00:12:01,444
to find out. Like you say, Margaret, definitely

312
00:12:01,444 --> 00:12:03,204
one for the fit the hardcore physicist, I

313
00:12:03,204 --> 00:12:05,764
think, especially something that's taken twenty years to

314
00:12:05,764 --> 00:12:06,424
get through.

315
00:12:07,049 --> 00:12:09,129
So amazing achievement, that one. And speaking of

316
00:12:09,129 --> 00:12:12,910
molecules, research have found some pretty interesting molecules

317
00:12:13,049 --> 00:12:15,690
on the asteroid Bennu, which has caught our

318
00:12:15,690 --> 00:12:17,549
eye, hasn't it, Margaret? What have they found?

319
00:12:18,009 --> 00:12:20,090
Well, Matin, it's almost a case of asking

320
00:12:20,090 --> 00:12:21,950
what haven't they found on Bennu.

321
00:12:22,295 --> 00:12:24,134
I mean, they might be looking for not

322
00:12:24,134 --> 00:12:26,535
finding Jimmy Hoffa or Bigfoot, but they found

323
00:12:26,535 --> 00:12:28,934
almost everything else. So back in February, we

324
00:12:28,934 --> 00:12:31,254
reported that two teams had found salt and

325
00:12:31,254 --> 00:12:33,815
certain amino acids in samples of the asteroid

326
00:12:33,815 --> 00:12:34,315
Bennu,

327
00:12:34,639 --> 00:12:37,919
which NASA's OSIRIS REx spacecraft visited back in

328
00:12:37,919 --> 00:12:38,659
2020.

329
00:12:39,279 --> 00:12:41,360
These samples got parachuted back to Earth in

330
00:12:41,360 --> 00:12:44,320
2023, and ever since then, various groups of

331
00:12:44,320 --> 00:12:46,799
scientists have been studying them, hoping to answer

332
00:12:46,799 --> 00:12:49,184
questions about what was around in the earliest

333
00:12:49,184 --> 00:12:51,745
solar system, chemically speaking, and how it led

334
00:12:51,745 --> 00:12:53,264
to the kinds of stuff we see around

335
00:12:53,264 --> 00:12:53,845
us today.

336
00:12:54,784 --> 00:12:57,424
Now finding salt and amino acids on an

337
00:12:57,424 --> 00:13:00,225
asteroid is interesting because they're both important for

338
00:13:00,225 --> 00:13:01,204
living organisms.

339
00:13:01,769 --> 00:13:04,089
Lots of animals, including us, need salt to

340
00:13:04,089 --> 00:13:04,589
survive,

341
00:13:04,970 --> 00:13:06,970
and amino acids are the building blocks of

342
00:13:06,970 --> 00:13:09,289
the DNA and RNA that provide the instructions

343
00:13:09,289 --> 00:13:10,269
for making life.

344
00:13:10,730 --> 00:13:13,449
So finding these fairly complex molecules on an

345
00:13:13,449 --> 00:13:15,149
asteroid is a pretty big deal.

346
00:13:16,105 --> 00:13:17,625
Then just a few days ago, we got

347
00:13:17,625 --> 00:13:20,504
some new results about Bennu's composition showing that

348
00:13:20,504 --> 00:13:23,704
the asteroid also contains traces of glucose and

349
00:13:23,704 --> 00:13:25,804
ribose, which are both essential sugars,

350
00:13:26,345 --> 00:13:28,664
plus a bunch of different nitrogen and oxygen

351
00:13:28,664 --> 00:13:31,440
containing organic compounds plus supernova

352
00:13:32,139 --> 00:13:34,220
dust. And this is all really adding to

353
00:13:34,220 --> 00:13:36,620
this idea that asteroids could have delivered some

354
00:13:36,620 --> 00:13:39,259
of the, quote, ingredients for life to the

355
00:13:39,259 --> 00:13:40,000
early Earth

356
00:13:40,300 --> 00:13:42,779
while it was still essentially a smoldering ball

357
00:13:42,779 --> 00:13:43,840
of empty rock,

358
00:13:44,274 --> 00:13:46,514
and thereby kick starting the process that led

359
00:13:46,514 --> 00:13:47,815
to the evolution of life.

360
00:13:48,434 --> 00:13:50,514
This is a hypothesis that's been kicking around

361
00:13:50,514 --> 00:13:52,855
for decades, but thanks to our OSIRIS REx

362
00:13:53,154 --> 00:13:55,875
and other sample return missions, we're finally getting

363
00:13:55,875 --> 00:13:58,455
some answers about how plausible it really is.

364
00:13:59,509 --> 00:14:01,350
However, if I could add just a little

365
00:14:01,350 --> 00:14:03,669
down note here, several of the scientists involved

366
00:14:03,669 --> 00:14:06,230
in this particular breakthrough are or were affiliated

367
00:14:06,230 --> 00:14:08,309
with NASA, which is the US National Air

368
00:14:08,309 --> 00:14:09,289
and Space Administration.

369
00:14:10,149 --> 00:14:12,894
NASA's facing massive budget cuts and layoff due

370
00:14:12,894 --> 00:14:14,975
to the anti science attitude of the current

371
00:14:14,975 --> 00:14:15,714
US government,

372
00:14:16,095 --> 00:14:18,514
and NASA's Goddard Space Flight Center in particular

373
00:14:18,815 --> 00:14:21,315
is looking at significant reductions in staffing.

374
00:14:21,855 --> 00:14:24,014
It's perhaps indicative of the situation that at

375
00:14:24,014 --> 00:14:25,774
least one of the scientists who led this

376
00:14:25,774 --> 00:14:27,154
research is in this breakthrough

377
00:14:27,500 --> 00:14:29,419
and was employed at NASA Goddard at the

378
00:14:29,419 --> 00:14:31,120
beginning of 02/2025

379
00:14:31,419 --> 00:14:32,639
is no longer there.

380
00:14:33,339 --> 00:14:35,339
So we like to celebrate breakthroughs, but this

381
00:14:35,339 --> 00:14:37,019
is kind of the reverse. It's a breakdown

382
00:14:37,019 --> 00:14:38,779
of the year in terms of our ability

383
00:14:38,779 --> 00:14:40,945
to discover things like this because if it

384
00:14:40,945 --> 00:14:42,865
continues, then we're gonna lose the people and

385
00:14:42,865 --> 00:14:45,284
skills we need to make these discoveries happen.

386
00:14:45,504 --> 00:14:47,184
In fact, we already are losing them, and

387
00:14:47,184 --> 00:14:48,945
we'd be remiss not to mention that somewhere

388
00:14:48,945 --> 00:14:49,764
in this podcast.

389
00:14:50,544 --> 00:14:52,945
Yeah. Very good point, Margaret. Breakdown of the

390
00:14:52,945 --> 00:14:54,625
year. Yeah. That's something we didn't want hope

391
00:14:54,625 --> 00:14:56,840
we wouldn't think think would have happened. But,

392
00:14:57,220 --> 00:14:59,639
very good point. But, you know, sending asteroid

393
00:15:00,019 --> 00:15:01,539
samples back to Earth and studying them, I

394
00:15:01,539 --> 00:15:02,980
mean, how cool is that for getting people

395
00:15:02,980 --> 00:15:05,220
into physics and astronomy and science and getting

396
00:15:05,220 --> 00:15:06,820
them excited? It's the kind of thing, especially

397
00:15:06,820 --> 00:15:08,894
younger people will be, you know, fascinated about.

398
00:15:08,894 --> 00:15:10,335
Yeah. If we only keep if we can

399
00:15:10,335 --> 00:15:12,274
only keep them there, it'd be fantastic. Yeah.

400
00:15:12,335 --> 00:15:14,095
So we're now halfway through our list of,

401
00:15:14,335 --> 00:15:16,014
the top 10 breakthroughs of the year for

402
00:15:16,014 --> 00:15:18,654
2025 in physics. We're gonna switch gear and

403
00:15:18,654 --> 00:15:20,274
move over to medical physics.

404
00:15:20,654 --> 00:15:22,735
And, Tammy, we've gone for some new work

405
00:15:22,735 --> 00:15:24,355
using what's known as proton

406
00:15:25,080 --> 00:15:25,820
arc therapy,

407
00:15:26,120 --> 00:15:28,680
which involves using protons to treat patients with

408
00:15:28,680 --> 00:15:30,279
cancer, but in a better manner than has

409
00:15:30,279 --> 00:15:31,420
been possible before.

410
00:15:32,279 --> 00:15:35,340
Yes. So this study is about proton therapy,

411
00:15:35,720 --> 00:15:38,304
a cancer treatment in which beams of protons

412
00:15:38,365 --> 00:15:41,164
are precisely directed onto a tumor to destroy

413
00:15:41,164 --> 00:15:42,225
targeted cells.

414
00:15:42,845 --> 00:15:45,964
Now currently, proton therapy is mostly performed using

415
00:15:45,964 --> 00:15:48,684
a technique called pencil beam scanning, in which

416
00:15:48,684 --> 00:15:50,845
a narrow beam of protons is scanned over

417
00:15:50,845 --> 00:15:52,769
the target to match the tumor shape

418
00:15:53,250 --> 00:15:55,410
with different beam energies used to build up

419
00:15:55,410 --> 00:15:58,290
depth layers and effectively paint the dose onto

420
00:15:58,290 --> 00:15:59,429
the tumor volume.

421
00:15:59,730 --> 00:16:03,009
Now this this approach provides highly conformal dose

422
00:16:03,009 --> 00:16:03,509
distributions,

423
00:16:04,050 --> 00:16:06,690
which means that the proton dose matches really

424
00:16:06,690 --> 00:16:08,389
well with the shape of the tumor.

425
00:16:08,855 --> 00:16:10,454
But it can be limited by the small

426
00:16:10,454 --> 00:16:12,615
number of beam directions that it can deliver

427
00:16:12,615 --> 00:16:14,714
in an acceptable treatment time.

428
00:16:16,134 --> 00:16:18,694
Now a team at the Trento Proton Therapy

429
00:16:18,694 --> 00:16:21,014
Center in Italy is working on a new

430
00:16:21,014 --> 00:16:22,315
type of treatment delivery

431
00:16:22,620 --> 00:16:24,399
called proton arc therapy.

432
00:16:25,340 --> 00:16:27,899
Here, the proton beams are irradiated onto the

433
00:16:27,899 --> 00:16:30,320
target at a large number of beam angles

434
00:16:30,379 --> 00:16:32,799
while the gantry moves in an arc trajectory

435
00:16:33,100 --> 00:16:34,080
around the patient.

436
00:16:34,460 --> 00:16:35,679
And during this rotation,

437
00:16:36,095 --> 00:16:38,674
the beam energy and intensity are adjusted

438
00:16:38,975 --> 00:16:41,455
to map the required dose onto the target

439
00:16:41,455 --> 00:16:41,955
volume.

440
00:16:43,535 --> 00:16:46,815
Now working with researchers at research laboratories in

441
00:16:46,815 --> 00:16:47,315
Sweden,

442
00:16:47,934 --> 00:16:51,190
the team compared proton arc therapy plans with

443
00:16:51,190 --> 00:16:53,610
state of the art pencil beam scanning plans

444
00:16:53,750 --> 00:16:55,850
for 10 patients with head and neck cancers.

445
00:16:56,709 --> 00:16:59,209
And they found that proton arc therapy improved

446
00:16:59,269 --> 00:17:01,829
the dose conformality compared with the pencil beam

447
00:17:01,829 --> 00:17:04,869
plans. So it did it delivered equivalent dose

448
00:17:04,869 --> 00:17:07,265
to the tumor target, but less dose to

449
00:17:07,265 --> 00:17:10,065
the nearby organs at risk, with the largest

450
00:17:10,065 --> 00:17:12,544
impact seen in reducing dose to the brain

451
00:17:12,544 --> 00:17:13,044
stem.

452
00:17:13,744 --> 00:17:16,384
And the team also ran a feasibility test

453
00:17:16,384 --> 00:17:19,184
that confirmed that it's actually possible to deliver

454
00:17:19,184 --> 00:17:21,444
this proton arc therapy in the clinic.

455
00:17:22,880 --> 00:17:25,759
The big breakthrough here is that following these

456
00:17:25,759 --> 00:17:29,039
initial tests, the researchers then performed the world's

457
00:17:29,039 --> 00:17:32,099
first clinical treatments using proton arc therapy.

458
00:17:32,960 --> 00:17:34,960
At the time of writing their paper, they

459
00:17:34,960 --> 00:17:36,740
treated nine cancer patients,

460
00:17:37,244 --> 00:17:39,325
five with head and neck tumors, three with

461
00:17:39,325 --> 00:17:41,585
brain tumors, and one with thoracic cancer.

462
00:17:42,365 --> 00:17:44,924
Now importantly, all of these treatments were performed

463
00:17:44,924 --> 00:17:48,305
using the medical center's existing proton therapy system

464
00:17:48,525 --> 00:17:50,545
and using the same clinical workflow.

465
00:17:51,565 --> 00:17:54,069
Looking ahead, the researchers aim to use this

466
00:17:54,069 --> 00:17:57,029
protonark therapy to treat tumors in other regions

467
00:17:57,029 --> 00:17:57,769
of the body.

468
00:17:58,630 --> 00:18:00,630
So a technique that potentially could really be

469
00:18:00,630 --> 00:18:02,650
of great benefit to, to people,

470
00:18:03,109 --> 00:18:04,724
with cancer. That sounds great,

471
00:18:05,605 --> 00:18:08,265
and really promising work. And over in biophysics,

472
00:18:08,404 --> 00:18:10,085
Tammy, if I can stick with you, this

473
00:18:10,085 --> 00:18:12,244
year, we reported on some really interesting work

474
00:18:12,244 --> 00:18:13,944
using a quantum bit

475
00:18:14,244 --> 00:18:16,424
that was formed from a fluorescent protein

476
00:18:16,900 --> 00:18:18,579
that could be used as a sensor that

477
00:18:18,579 --> 00:18:21,700
can be directly produced inside living cells. Now

478
00:18:21,700 --> 00:18:23,859
to me, this sounds really fascinating. It's quantum

479
00:18:23,859 --> 00:18:25,000
physics and biophysics

480
00:18:25,299 --> 00:18:27,220
and a new kind of sensor. So do

481
00:18:27,220 --> 00:18:29,240
you wanna tell us about this one? Sure.

482
00:18:30,144 --> 00:18:32,704
So this breakthrough is from researchers at the

483
00:18:32,704 --> 00:18:36,244
University of Chicago, Pritzker School of Molecular Engineering.

484
00:18:37,025 --> 00:18:40,065
And they designed a protein quantum bit or

485
00:18:40,065 --> 00:18:40,565
qubit

486
00:18:40,945 --> 00:18:43,365
that can be produced inside living cells.

487
00:18:43,730 --> 00:18:45,890
And this protein qubit can be used as

488
00:18:45,890 --> 00:18:48,849
a quantum sensor that can detect tiny changes

489
00:18:48,849 --> 00:18:50,230
in magnetic fields.

490
00:18:51,089 --> 00:18:53,650
So many of today's quantum sensors are based

491
00:18:53,650 --> 00:18:56,230
on nitrogen vacancy or NV

492
00:18:56,884 --> 00:18:58,024
sensors in diamond.

493
00:18:58,484 --> 00:19:01,204
And when excited with laser pulses, these crystal

494
00:19:01,204 --> 00:19:03,845
defects emit a fluorescent signal that can be

495
00:19:03,845 --> 00:19:06,664
used to monitor slight changes in the magnetic

496
00:19:06,724 --> 00:19:08,585
properties of a nearby sample.

497
00:19:09,630 --> 00:19:13,089
For biological applications, however, these sensors are relatively

498
00:19:13,150 --> 00:19:16,990
large, and they're difficult to precisely position inside

499
00:19:16,990 --> 00:19:17,890
living cells.

500
00:19:18,750 --> 00:19:21,869
So instead, the team, led by Peter Maurer

501
00:19:21,869 --> 00:19:22,930
and David Avshalom,

502
00:19:23,615 --> 00:19:26,015
took a biological system and turned it into

503
00:19:26,015 --> 00:19:26,674
a qubit.

504
00:19:27,455 --> 00:19:29,775
They used fluorescent proteins that are just three

505
00:19:29,775 --> 00:19:30,994
nanometers in diameter

506
00:19:31,455 --> 00:19:33,234
and can be genetically encoded

507
00:19:33,535 --> 00:19:35,695
such that they're produced by cells at a

508
00:19:35,695 --> 00:19:38,035
desired location with atomic precision.

509
00:19:39,430 --> 00:19:41,670
What's special about these proteins is that they

510
00:19:41,670 --> 00:19:43,849
possess similar optical and spin properties

511
00:19:44,150 --> 00:19:46,410
to those of NV center based qubits,

512
00:19:46,950 --> 00:19:48,250
in that they have a metastable

513
00:19:48,630 --> 00:19:49,690
triplet state.

514
00:19:51,285 --> 00:19:53,525
So to demonstrate that their idea worked, the

515
00:19:53,525 --> 00:19:57,285
researchers created an optically addressable spin qubit in

516
00:19:57,285 --> 00:19:58,984
a yellow fluorescent protein,

517
00:19:59,285 --> 00:20:01,365
and they used a near infrared laser pulse

518
00:20:01,365 --> 00:20:03,285
to read out its triplet state with up

519
00:20:03,285 --> 00:20:05,065
to 20% spin contrast.

520
00:20:06,484 --> 00:20:09,670
Next, they genetically modified the protein so that

521
00:20:09,670 --> 00:20:12,710
it was expressed in bacterial cells, and they

522
00:20:12,710 --> 00:20:15,750
measured signals in this case with a, contrast

523
00:20:15,750 --> 00:20:16,970
of up to 8%.

524
00:20:17,750 --> 00:20:18,970
So while this performance

525
00:20:19,269 --> 00:20:22,170
doesn't match that of the NV quantum sensors,

526
00:20:22,914 --> 00:20:26,375
These fluorescent proteins could enable magnetic resonance measurements

527
00:20:26,595 --> 00:20:30,035
directly inside living cells, which NV centers simply

528
00:20:30,035 --> 00:20:30,855
cannot do.

529
00:20:31,954 --> 00:20:34,035
And because of this, Maurer suggests that the

530
00:20:34,035 --> 00:20:35,174
new protein qubits

531
00:20:35,579 --> 00:20:37,599
could transform medical and biochemical

532
00:20:37,900 --> 00:20:38,400
studies

533
00:20:39,019 --> 00:20:43,099
by probing protein folding, monitoring redox states, or

534
00:20:43,099 --> 00:20:45,679
detecting drug binding at the molecular scale.

535
00:20:46,059 --> 00:20:48,779
So thanks, Tammy. That's some fascinating, biophysics and

536
00:20:48,779 --> 00:20:51,054
quantum physics. And we're down to the final

537
00:20:51,054 --> 00:20:52,815
three picks for the breakthrough of the year

538
00:20:52,815 --> 00:20:54,674
in physics for 2025.

539
00:20:54,734 --> 00:20:56,255
Hamish, I'm gonna come back to you now

540
00:20:56,255 --> 00:20:58,835
for some imaging and condensed matter physicists,

541
00:20:59,294 --> 00:21:01,694
with physicists saying that they've recorded the highest

542
00:21:01,694 --> 00:21:02,514
ever resolution

543
00:21:02,894 --> 00:21:04,595
images of a single atom.

544
00:21:05,099 --> 00:21:06,779
Well, we do like breaking records here at

545
00:21:06,779 --> 00:21:08,460
Physics World. So, do you wanna tell us

546
00:21:08,460 --> 00:21:09,980
about this one? And can you pronounce the

547
00:21:09,980 --> 00:21:10,480
technique?

548
00:21:10,779 --> 00:21:13,099
It's got a funny name. Well, we'll see.

549
00:21:13,099 --> 00:21:14,240
Yeah. So,

550
00:21:14,539 --> 00:21:17,019
yes, this this is a a breakthrough in

551
00:21:17,019 --> 00:21:17,819
terms of,

552
00:21:18,605 --> 00:21:20,545
resolution with an electron micros-

553
00:21:20,845 --> 00:21:23,884
with an electron microscope. But there's much much

554
00:21:23,884 --> 00:21:26,205
more to it, which is why we selected

555
00:21:26,205 --> 00:21:27,984
it. This is related to twisted

556
00:21:28,445 --> 00:21:30,224
materials, this idea of twistronics.

557
00:21:31,005 --> 00:21:32,305
When you take two

558
00:21:32,609 --> 00:21:33,009
atomic,

559
00:21:33,569 --> 00:21:34,069
atomically

560
00:21:34,369 --> 00:21:34,869
thin

561
00:21:35,250 --> 00:21:38,130
lattice layers and twist them with respect to

562
00:21:38,130 --> 00:21:39,490
each other, and you can get some really

563
00:21:39,490 --> 00:21:39,990
strange,

564
00:21:41,009 --> 00:21:43,509
properties in these, twisted systems.

565
00:21:44,369 --> 00:21:47,109
The result is something called a moire superlattice

566
00:21:47,804 --> 00:21:49,984
of atoms. And you can by

567
00:21:50,524 --> 00:21:51,904
adjusting the twist angle,

568
00:21:52,204 --> 00:21:55,484
you can adjust this superlattice, the distance between

569
00:21:55,484 --> 00:21:56,065
the atoms,

570
00:21:56,524 --> 00:21:59,184
and then you can also adjust the electronic

571
00:21:59,244 --> 00:22:00,625
properties of the system,

572
00:22:01,480 --> 00:22:04,380
which researchers have found to be very useful.

573
00:22:05,000 --> 00:22:06,779
And in this, study,

574
00:22:07,079 --> 00:22:10,059
Yichao Zhang at the University of Maryland

575
00:22:10,519 --> 00:22:12,059
and Pinshain Huang

576
00:22:12,359 --> 00:22:14,140
of the University of Illinois

577
00:22:14,519 --> 00:22:15,179
at Urbana

578
00:22:15,644 --> 00:22:16,144
Champaign,

579
00:22:16,605 --> 00:22:18,224
have used a technique called

580
00:22:18,684 --> 00:22:19,904
electron tachygraphy

581
00:22:20,924 --> 00:22:22,945
to capture the highest resolution

582
00:22:23,404 --> 00:22:24,545
images ever

583
00:22:24,924 --> 00:22:25,664
of atoms,

584
00:22:26,285 --> 00:22:28,224
and they've done so in a moire

585
00:22:28,799 --> 00:22:29,299
superlattice

586
00:22:29,840 --> 00:22:30,900
made of tungsten

587
00:22:31,279 --> 00:22:31,779
diselenide.

588
00:22:32,799 --> 00:22:33,299
Now,

589
00:22:33,600 --> 00:22:34,660
electron ticography,

590
00:22:34,960 --> 00:22:36,420
it's an electron microscopy

591
00:22:36,720 --> 00:22:37,220
technique

592
00:22:37,600 --> 00:22:38,980
that uses diffraction

593
00:22:39,440 --> 00:22:42,884
to boost the resolution of electron microscopy. Now,

594
00:22:43,125 --> 00:22:46,404
electron microscopy has got pretty high resolution already,

595
00:22:46,404 --> 00:22:49,765
and you can see individual atoms with, some

596
00:22:49,765 --> 00:22:50,744
electron microscopes.

597
00:22:51,125 --> 00:22:54,184
But diffraction is used to to improve this.

598
00:22:54,484 --> 00:22:56,759
And they were able to look

599
00:22:57,240 --> 00:22:58,619
at this moire superlattice

600
00:22:59,160 --> 00:23:00,059
at a resolution

601
00:23:00,440 --> 00:23:01,259
of 15

602
00:23:01,720 --> 00:23:02,220
picometers.

603
00:23:03,400 --> 00:23:05,880
And that's pretty good when you consider that

604
00:23:05,880 --> 00:23:06,700
the size

605
00:23:07,000 --> 00:23:08,920
of an atom. Okay, what's the size of

606
00:23:08,920 --> 00:23:11,345
an atom? It's a bit wooly, the definition.

607
00:23:11,644 --> 00:23:14,525
But typically, you know, it's defined to be

608
00:23:14,525 --> 00:23:15,505
about a 100

609
00:23:16,365 --> 00:23:16,865
picometres,

610
00:23:17,164 --> 00:23:19,884
a 150 picometres, so they're you know, the

611
00:23:19,884 --> 00:23:22,464
resolution is much much smaller

612
00:23:22,765 --> 00:23:24,944
than the actual size of the atoms

613
00:23:25,289 --> 00:23:26,509
that they're looking at.

614
00:23:27,289 --> 00:23:28,670
And I suppose

615
00:23:29,130 --> 00:23:30,410
a a very interesting thing,

616
00:23:30,970 --> 00:23:33,789
that they used this technique to do

617
00:23:34,090 --> 00:23:37,150
is they looked at collective lattice vibrations

618
00:23:37,769 --> 00:23:39,630
called moire phasons.

619
00:23:40,505 --> 00:23:42,424
And so these are a bit like, the

620
00:23:42,424 --> 00:23:43,565
familiar phonons,

621
00:23:44,424 --> 00:23:44,924
collective

622
00:23:45,304 --> 00:23:48,204
sound waves that occur in normal lattices.

623
00:23:48,744 --> 00:23:51,565
But they occur in these moire superlattices,

624
00:23:51,865 --> 00:23:54,909
and they're actually much lower energy and much

625
00:23:54,909 --> 00:23:55,409
weaker,

626
00:23:56,509 --> 00:23:57,809
but they do have,

627
00:23:58,190 --> 00:24:01,970
a very important effect on the electronic properties

628
00:24:02,269 --> 00:24:03,970
of these twisted materials.

629
00:24:04,750 --> 00:24:05,389
And so,

630
00:24:05,869 --> 00:24:08,690
by using this technique to observe these phasons,

631
00:24:11,125 --> 00:24:11,605
physicists,

632
00:24:11,924 --> 00:24:14,984
have the chance to really understand why

633
00:24:15,285 --> 00:24:18,805
these twisted materials have these really strange and

634
00:24:18,805 --> 00:24:19,305
exotic

635
00:24:19,684 --> 00:24:23,990
electronic properties. Because often these electronic properties arise

636
00:24:23,990 --> 00:24:27,349
because of interactions between the electrons and the

637
00:24:27,349 --> 00:24:28,330
lattice vibrations,

638
00:24:28,710 --> 00:24:30,809
you know, the classic example being superconductivity.

639
00:24:31,990 --> 00:24:32,390
So,

640
00:24:33,589 --> 00:24:35,609
yeah, a very a very high resolution

641
00:24:36,070 --> 00:24:36,404
elect,

642
00:24:36,884 --> 00:24:38,505
electron microscopy technique

643
00:24:38,884 --> 00:24:41,125
that opens up a new field, a new

644
00:24:41,125 --> 00:24:42,025
way of studying,

645
00:24:42,884 --> 00:24:45,765
these materials. So, yep, very exciting, and that's

646
00:24:45,765 --> 00:24:48,644
why it's in our top 10. Brilliant stuff,

647
00:24:48,644 --> 00:24:50,309
Hamish. Thanks very much. And if I can

648
00:24:50,309 --> 00:24:52,069
stick with you, now we always do know

649
00:24:52,069 --> 00:24:54,950
that particle physics gets, people very excited. And

650
00:24:54,950 --> 00:24:57,190
our penultimate pick for this year is some

651
00:24:57,190 --> 00:24:58,409
work done at CERN,

652
00:24:58,789 --> 00:25:01,429
where researchers at the base experiments have measured

653
00:25:01,429 --> 00:25:05,154
the magnetic properties of antimatter with record breaking

654
00:25:05,214 --> 00:25:05,714
precision.

655
00:25:06,575 --> 00:25:08,734
Tell us about this one, Hamish. Well, this

656
00:25:08,734 --> 00:25:10,255
is I mean, this has to do with

657
00:25:10,255 --> 00:25:11,875
one of the biggest mysteries

658
00:25:12,494 --> 00:25:13,154
of physics.

659
00:25:13,775 --> 00:25:16,974
And that mystery is why is there much

660
00:25:16,974 --> 00:25:17,795
more matter

661
00:25:18,319 --> 00:25:21,519
than antimatter in the visible universe? The the

662
00:25:21,519 --> 00:25:22,980
standard model says

663
00:25:23,359 --> 00:25:23,680
that,

664
00:25:24,240 --> 00:25:26,819
when the universe began in the big bang,

665
00:25:26,960 --> 00:25:28,960
there would have been roughly equal amounts of

666
00:25:28,960 --> 00:25:30,259
matter and antimatter.

667
00:25:30,664 --> 00:25:32,744
But when we look around us well, you

668
00:25:32,744 --> 00:25:34,664
know, look around the room that you're in,

669
00:25:34,664 --> 00:25:38,265
it's all matter. There's very little antimatter. Really,

670
00:25:38,265 --> 00:25:41,244
the only antimatter that we see comes from,

671
00:25:41,784 --> 00:25:43,484
you know, sort of nuclear processes,

672
00:25:44,105 --> 00:25:46,524
you know, both in in stars and in

673
00:25:47,440 --> 00:25:49,680
in, colliders here on Earth. There there's not

674
00:25:49,680 --> 00:25:51,539
a lot of antimatter out there.

675
00:25:53,039 --> 00:25:55,840
And so there are, there's a series of

676
00:25:55,840 --> 00:25:58,100
experiments, base is one of them at CERN,

677
00:25:58,320 --> 00:25:59,539
where they create,

678
00:26:00,320 --> 00:26:00,820
antimatter

679
00:26:01,365 --> 00:26:01,724
in,

680
00:26:02,164 --> 00:26:03,224
in an accelerator,

681
00:26:03,924 --> 00:26:05,065
and they do

682
00:26:05,365 --> 00:26:07,785
really, really precise measurements on it.

683
00:26:08,404 --> 00:26:09,625
And in this case,

684
00:26:10,005 --> 00:26:11,944
researchers on the base experiment

685
00:26:12,244 --> 00:26:14,345
managed to trap a single

686
00:26:14,724 --> 00:26:15,224
antiproton

687
00:26:16,130 --> 00:26:17,029
in an electromagnetic

688
00:26:17,890 --> 00:26:18,390
trap

689
00:26:18,690 --> 00:26:21,269
and use quantum control techniques

690
00:26:21,809 --> 00:26:22,950
to measure the

691
00:26:23,330 --> 00:26:26,630
antiproton's magnetic properties, basically, its spin,

692
00:26:27,809 --> 00:26:28,630
very precisely.

693
00:26:29,170 --> 00:26:31,830
In fact, 16 times more precise

694
00:26:32,945 --> 00:26:33,684
than before.

695
00:26:34,945 --> 00:26:37,285
And, you know, this is very difficult because

696
00:26:37,424 --> 00:26:39,585
first, you have to create the antiprotons, and

697
00:26:39,585 --> 00:26:41,825
that's done in a collider, and they come

698
00:26:41,825 --> 00:26:44,065
out at very high energy. You have to

699
00:26:44,065 --> 00:26:45,125
slow them down.

700
00:26:46,250 --> 00:26:48,109
You have to sort of store them

701
00:26:48,649 --> 00:26:50,190
at very, very low temperatures

702
00:26:50,649 --> 00:26:53,289
and then do your experiments. And at any

703
00:26:53,289 --> 00:26:54,589
point in this process,

704
00:26:54,970 --> 00:26:57,929
if that anti piece of antimatter comes into

705
00:26:57,929 --> 00:27:00,509
contact with matter, which is, of course, everywhere,

706
00:27:01,244 --> 00:27:04,045
it'll annihilate and you lose it. So it's

707
00:27:04,045 --> 00:27:06,545
a really, really difficult process accumulating

708
00:27:07,244 --> 00:27:08,305
all this antimatter.

709
00:27:08,924 --> 00:27:11,244
And then amazingly, you know, they hold it

710
00:27:11,244 --> 00:27:12,144
in their trap

711
00:27:12,445 --> 00:27:14,785
for long enough to do these quantum manipulations

712
00:27:15,269 --> 00:27:15,769
and,

713
00:27:16,630 --> 00:27:17,450
and measure

714
00:27:18,070 --> 00:27:20,009
the, the its properties.

715
00:27:20,470 --> 00:27:22,230
And and and the reason they want to

716
00:27:22,230 --> 00:27:23,029
do this is,

717
00:27:23,990 --> 00:27:25,450
the the standard model,

718
00:27:26,070 --> 00:27:28,809
basically says that matter and antimatter

719
00:27:29,684 --> 00:27:32,404
should be roughly the same except, you know,

720
00:27:32,404 --> 00:27:35,044
for the the obvious that one's matter and

721
00:27:35,044 --> 00:27:35,865
one's antimatter.

722
00:27:36,404 --> 00:27:39,444
So what what the ultimate goal is to

723
00:27:39,444 --> 00:27:42,265
measure the magnetic properties of the antiproton

724
00:27:43,000 --> 00:27:45,559
and compare it to the magnetic properties of

725
00:27:45,559 --> 00:27:46,299
the proton.

726
00:27:46,839 --> 00:27:49,019
And these should be, well, identical

727
00:27:49,400 --> 00:27:51,740
with the exception of a flip in,

728
00:27:52,599 --> 00:27:54,859
in the side the charge on the particle.

729
00:27:55,325 --> 00:27:57,244
And so if they can find even the

730
00:27:57,244 --> 00:27:57,984
most minute

731
00:27:58,285 --> 00:28:00,944
differences between the proton and the antiproton,

732
00:28:01,644 --> 00:28:03,025
that could lead to physics

733
00:28:03,565 --> 00:28:05,105
beyond the standard model

734
00:28:05,565 --> 00:28:08,065
and also tell us why there's more matter

735
00:28:08,365 --> 00:28:09,265
than antimatter

736
00:28:09,700 --> 00:28:10,519
in the universe.

737
00:28:11,220 --> 00:28:11,720
So

738
00:28:12,259 --> 00:28:15,299
exciting experiment, and who knows? Hopefully, they'll they'll

739
00:28:15,299 --> 00:28:17,380
find a difference between the proton and the

740
00:28:17,380 --> 00:28:17,880
antiproton.

741
00:28:18,180 --> 00:28:20,019
I always think with antimatter, we need another

742
00:28:20,019 --> 00:28:22,340
Dan Brown novel to follow angels and demons

743
00:28:22,340 --> 00:28:24,259
when they used antimatter, and that was the

744
00:28:24,259 --> 00:28:25,214
the plot hook.

745
00:28:26,174 --> 00:28:28,335
Now completing our list of the top 10

746
00:28:28,335 --> 00:28:30,015
breakthroughs of the year in physics as picked

747
00:28:30,015 --> 00:28:31,154
by Physics World,

748
00:28:31,534 --> 00:28:33,855
we've gone some for some condensed matter physics

749
00:28:33,855 --> 00:28:36,335
that seems pretty straightforward in principle, but,

750
00:28:36,894 --> 00:28:38,335
it seems to have taken quite a lot

751
00:28:38,335 --> 00:28:40,599
of effort, and that is in making two

752
00:28:40,599 --> 00:28:41,819
dimensional metals.

753
00:28:42,519 --> 00:28:44,119
So, Michael, can you tell us more about

754
00:28:44,119 --> 00:28:44,779
this one?

755
00:28:45,079 --> 00:28:46,759
Yeah. So this breakthrough is about the first

756
00:28:46,759 --> 00:28:48,700
creation of two d sheets of metal.

757
00:28:49,000 --> 00:28:50,440
So since 2004,

758
00:28:50,440 --> 00:28:52,359
we know that some materials can form flat

759
00:28:52,359 --> 00:28:54,059
sheets known as two d materials,

760
00:28:54,464 --> 00:28:56,244
graphene being one prime example.

761
00:28:56,785 --> 00:28:59,105
Such materials are about one atom thick, and

762
00:28:59,105 --> 00:29:01,345
in the case of graphene occur because you

763
00:29:01,345 --> 00:29:03,444
have a layer of atoms that are separated

764
00:29:03,505 --> 00:29:05,924
by gaps between neighboring layers.

765
00:29:06,539 --> 00:29:08,860
This means that you can effectively shave off

766
00:29:08,860 --> 00:29:10,880
layers to make two d sheets.

767
00:29:11,420 --> 00:29:13,660
Things are a bit different, however, for metals.

768
00:29:13,660 --> 00:29:16,140
In the case of metals, atoms are strongly

769
00:29:16,140 --> 00:29:19,019
bounded to surrounding atoms in all directions, which

770
00:29:19,019 --> 00:29:20,559
makes cleaving difficult.

771
00:29:21,274 --> 00:29:23,034
To get around this problem and create two

772
00:29:23,034 --> 00:29:25,274
d sheets of metal, the researchers who are

773
00:29:25,274 --> 00:29:28,075
based in China heated powders of pure metals

774
00:29:28,075 --> 00:29:29,534
and melted them into droplets.

775
00:29:30,075 --> 00:29:32,474
They then applied a pressure of around 200

776
00:29:32,474 --> 00:29:33,774
megapascal, effectively

777
00:29:34,075 --> 00:29:37,440
squeezing the opposite sides of these anvils until

778
00:29:37,440 --> 00:29:39,539
two d sheets of metals were formed.

779
00:29:40,079 --> 00:29:42,799
The team managed to produce five atomically thin

780
00:29:42,799 --> 00:29:45,140
two d metals. That's bismuth,

781
00:29:45,440 --> 00:29:48,799
tin, lead, indium, and gallium, with the thinnest

782
00:29:48,799 --> 00:29:50,320
being around 6.3

783
00:29:50,320 --> 00:29:50,820
angstrom.

784
00:29:51,654 --> 00:29:53,335
The researchers say their work is just a

785
00:29:53,335 --> 00:29:55,255
tip of the iceberg, and they now aim

786
00:29:55,255 --> 00:29:57,755
to study fundamental physics with the new materials.

787
00:29:58,055 --> 00:29:59,194
So watch this space.

788
00:30:00,855 --> 00:30:03,035
So that's all of our top 10 breakthroughs

789
00:30:03,174 --> 00:30:05,319
for this year as picked by Physics World.

790
00:30:05,319 --> 00:30:07,419
We've had some astronomy, some geoscience,

791
00:30:07,880 --> 00:30:08,859
condensed matter,

792
00:30:09,240 --> 00:30:12,119
a bit of particle physics, biophysics, medical physics,

793
00:30:12,119 --> 00:30:13,339
and optical physics.

794
00:30:13,880 --> 00:30:15,720
But to find out who's bagged the overall

795
00:30:15,720 --> 00:30:17,960
top prize for Physics World's breakthrough of the

796
00:30:17,960 --> 00:30:19,500
year for 2025,

797
00:30:20,144 --> 00:30:22,805
Check back on Thursday, December 18,

798
00:30:23,025 --> 00:30:25,184
where we'll reveal the winner in a new

799
00:30:25,184 --> 00:30:27,105
story and in the next episode of the

800
00:30:27,105 --> 00:30:28,805
Physics World weekly podcast.

801
00:30:29,825 --> 00:30:32,644
So a big thank you to Tammy, Margaret,

802
00:30:32,865 --> 00:30:35,045
Michael, and Hamish for joining me today.

803
00:30:35,460 --> 00:30:38,359
And a special thanks to producer Fred Isles.

804
00:30:38,419 --> 00:30:40,419
And thanks for listening, and do join us

805
00:30:40,419 --> 00:30:42,500
again next week for the big reveal of

806
00:30:42,500 --> 00:30:45,720
Physics World's breakthrough of the year for 2025.