Robyn Williams: Nearly as surreal because the chat I had with Professor Frank Wilczek final week, about time reversals in biology. And I promised to have a genius this week to elucidate all of it, or a few of it. So here is Professor Paul Davies.

Frank is a pal of yours, and you have identified him for a very long time. And he defined to me what he means by some type of time reversal occurring in organic methods, most of which I didn’t comprehend in any respect. Did you perceive what he is getting at? Or is it a figment, is it a product of the arithmetic, as typically produces unusual issues?

Paul Davies: Nicely, Frank is a particle physicist, they usually’re in thrall of symmetry as mathematical descriptions of the world, and on the degree of basic particles, that is a extremely highly effective method. Making use of it to dwelling organisms is a good leap. And that is clearly a piece in progress, however it is going to be fascinating to know whether or not one can categorise numerous varieties of organic processes in accordance with their properties underneath the imaginary mathematical course of we name time reversal.

So we all know that electrical energy and magnetism go hand in hand, they make one another, however the distinction is electrical prices can simply sit there however magnetic fields are made by transferring prices, currents, electrical currents, going spherical and spherical, for instance. Now, should you think about taking a film of electrical prices and currents going round and round, play the film backward, the present goes again the opposite approach, and that reverses the magnetic discipline. So underneath this mathematical means of time reversal, electrical issues keep the identical, magnetic issues flip.

Now, that is undeniably true, and it is actually necessary in particle physics: is it necessary in biology? Nicely, we’ll have to attend and see what Frank finds out. However he appears to be hinting that electrical fields are nice for manipulating and possibly processing or garnering power, however magnetic fields are higher for storage. And certainly, I feel you are interviewing me with a tool that’s storing what I am saying magnetically in that gizmo down there.

Robyn Williams: We hope it’s anyway! We ask you maybe to test with him whenever you get again to Arizona State College. Speaking about time, time crystals is one thing else he is been engaged on, which he’s going to say.

Paul Davies: Sure. Frank, I ought to say, is one thing of a genius, and he is at all times developing with actually neat concepts. And once more, that is one thing that comes from his preoccupation with symmetry. Now, this can be a very simple factor to elucidate. The legal guidelines of physics do not range from place to put, the legal guidelines of physics are the identical on that facet of the room as they’re on this facet of the room. However we all know that there are bodily objects that break that symmetry. Simply because the legal guidelines of physics have a symmetry doesn’t suggest the stuff round us displays that symmetry.

And the best instance of breaking that symmetry is the crystal. It is periodic, it has a lattice, so it repeats itself. And also you would possibly suppose, effectively, it’s symmetric, however we are saying it is a discrete symmetry. If you happen to leap by one sq., a bit like a checkerboard, go one sq. throughout, it seems to be the identical, however inside a sq., you could be close to the sting or close to the center, and so forth, that symmetry is damaged. So crystals spontaneously break the interpretation symmetry in house.

And Frank puzzled some years in the past, are there methods that break that symmetry in time? As a result of the legal guidelines of physics do not range from at some point to the subsequent, it is going to be the identical tomorrow as they’re at present. That is one thing that may break that, like a crystal breaks it in house, it is going to be a crystal in time. And also you would possibly suppose, effectively, there are many issues that try this, a pendulum, for instance, is periodic, it returns to the identical place, backwards and forwards and backwards and forwards. That does not actually matter as a result of the pendulum will finally, should you set it swinging, will dissipate power, generate entropy, and it’ll come to a cease. So is there one thing that can simply flip-flop without end with out having to be pushed? And that was the thought of the time crystal.

It seems whenever you take a look at the nuances of it, to create one thing like a time crystal, you do should have a driving power of some kind, at the very least within the experiments achieved thus far. However positive sufficient, there are methods, and these are quantum methods, quantum many-body methods. So we all know in quantum mechanics, all types of magical issues can occur. However these items do flop right into a form of periodic movement with a distinct interval from the one which’s driving them, it is a a number of of that. And so it appears to be demonstrating the spirit of what Frank had in thoughts with the time crystals when he first instructed it. And there could also be many different methods and plenty of different varieties of many-body methods that might show this order in time, identical to standard crystals like salt and diamonds show order in house.

Robyn Williams: I hoped it might need one thing to do virtually, resembling in Physician Who’s TARDIS, you realize, a time crystal sounds, the best way you had been describing it, with driving and all the remainder of it, best. However are you able to discover it virtually in any approach?

Paul Davies: Nicely, you see, it doesn’t suggest that I offer you a crystal and it magically takes you again into the previous, crystal energy, not that form of crystal energy. There have been speculations that possibly time crystals might be used for information storage in quantum computing. They’re basically quantum methods. And the factor about quantum methods is we all know from one thing like superconductivity that issues can form of transfer effortlessly via a matrix, like go sliding via a wall. And right here, we’d think about one thing that may once more, be easy, it would not dissipate power, it might effortlessly repeat itself. And that is the important thought, I feel, that is underpinning the time crystals.

After all, all of us eagerly await what Frank will provide you with subsequent, as a result of that is solely a few the issues that he is well-known for. I feel the underlying story connecting these two issues is the notion of symmetry and symmetry breaking. And that displays Frank’s background as a particle physicist the place that is such a strong approach of continuing.

Robyn Williams: Paul Davies is Regents Professor at Arizona State College. And, as he stated, Frank Wilczek is a type of, like Steve Weinberg, who revealed the elemental nature of the nucleus, the usual mannequin of the atom.

You talked about Steve Weinberg, the daddy, should you like, of the usual mannequin…

Frank Wilczek: Nicely, the weak interactions half.

Robyn Williams: The weak half and you are the robust half. After which there’s gravity and, in fact, electromagnetism. However the first fast query is what’s a time crystal?

Frank Wilczek: Okay, effectively, time crystal has little or no to do with the usual mannequin really. It would not contradict it, but it surely’s an unbiased idea. And it additionally has to do with symmetry of time, we have been speaking fairly a bit about symmetry and reversing the route of time. However one other symmetry that is completely basic in science, possibly probably the most basic symmetry of all, is what’s known as symmetry underneath translation of time, which is a approach of claiming that the legal guidelines do not change, the legal guidelines are the identical as time goes on. We would be in serious trouble if that weren’t true. In order that’s a basic symmetry.

However we all know that in supplies, many symmetries which might be symmetries of basic legal guidelines are decreased. So, as an illustration, what I stated about time you might additionally say about house. If you happen to might take a look at how the legal guidelines work at completely different locations, you get the identical legal guidelines. So the man within the subsequent door laboratory you count on to measure the identical plenty of atoms and spectra and all these items. And that does not should be true, but it surely seems to be true.

Nevertheless, in supplies, that symmetry could be damaged. You’ve got crystals. If you happen to transfer slightly bit, think about transferring in house from the place the place an atom is in a crystal lattice to the place an atom is not, clearly issues are completely different. So the crystal has much less symmetry than this excellent symmetry of spatial translation.

And so a number of years in the past I requested a query, whether or not there could be supplies the place you’ve as an alternative of breaking of the interpretation symmetry of house, you’ve breaking of the interpretation symmetry in time. And underneath my spouse’s affect I named them time crystals. Now, many issues on the earth break time translation symmetry, issues get previous. You may have issues like heartbeats which might be common, however they don’t seem to be at all times doing the identical factor. However the idea of time crystal is you need one thing the place this occurs spontaneously, simply autonomously. It is doing this as a result of it needs to do it, like crystals type. And that introduces a complication. And other people have completely different notions of what counts as an remoted system, what counts because the factor doing it spontaneously, do you need to push and prod? What’s allowed? However that is the essential idea. I ought to add now that it is gone from being a purely theoretical notion to a thriving experimental enterprise.

Robyn Williams: Thought experiment; if Stephen Hawking had been right here nonetheless, and he requested you to signal a letter with him about AI and its risks, would you?

Frank Wilczek: Nicely, if I wrote the letter, which is what occurred the primary time round, although it obtained edited. Nicely, it relies upon what it says. It is a nuanced query. To me, I do not suppose we must be too frightened and conceal underneath our desks like in fallout shelters as a result of the AIs are out to get us. However I do suppose there are actual points, they’re addressable points, and I feel in the event that they’re attended to, AI can be very useful.

Robyn Williams: So long as they do not go to battle.

Frank Wilczek: Nicely, one of many important issues is that we pay particular consideration to army makes use of of AI. And the stuff you need a army AI to do are form of on the sting of being very, very harmful. And particularly because the work will get achieved in secret, and you do not know what the opposite man is doing, you realize, it is a very doubtlessly unstable, harmful state of affairs. However we as a society have confronted different risks like nuclear power, and, for that matter, organic engineering as effectively is an one other one, and thus far they have been manageable. I simply hope we keep fortunate. Nevertheless it’s not simply luck, you need to concentrate.

Robyn Williams: Some ideas from Frank Wilczek, who gained the Nobel Prize and is commonly at Arizona State College, with Paul Davies. Some bewildering concepts on the symmetrical frontiers of physics.