What are the laws of the universe? | Laura Mersini-Houghton, Gerard 't Hooft, Helen Beebee

the laws of the universe since Newton at least people like Newton scientists most of us have assumed the universe is governed by unchanging laws even if God didn't put them down they were there but are the laws that we think of as universal and unchanging are they if they are how do they emerge where do they live how do they have their effect or are they are we mistaken are they not universal laws not written in stone somewhere are they just human constructs that are going to remain unknowable and inexplicable and we're just sort of approximating on my right Helen Beebe Manchester professor of philosophy I never get Nobel prize-winning physicist and left his left Laura Mercier Houghton cosmologists professor of physics which was trying to discover how this universe might actually have come into being she stumbled upon the multiverse and has caused confusion ever since are the laws eternal features of this universe obviously one distinctive feature of laws is they seem to be universal or at least they're very general sorts of things that's not just true in astrophysics or quantum mechanics it's true in chemistry and biology choose at least some extent even in things like psychology and the social sciences so at least one thing that laws do is somehow encode deep and pervasive regularities in the universe but for me from a metaphysical point of view because I am a meta physician the really interesting and puzzling question is this are they just a way of encoding those regularities are they just generally generalizations that we formulate that happen to apply you know always and everywhere or are they somehow things that lie behind those regularities things that make the universe unfold in this orderly and regular way that it does so in the word law is really suggestive right when we talk about laws of nature so when we talk about the laws of the land right don't steal people's stuff don't go around people don't commit perjury and so on obviously those laws aren't just ways of encoding regularities I mean for one thing they're not even regularities because people break the law all the time as we know but more importantly those sorts of laws are prescriptive things right there things that we obey or not as the case may be so the wards law as applied to the laws of nature kind of suggests that they're prescriptive as well there's somehow rules that everything abides by but now here's the mystery how on earth could that happen right that's a really strange thing so we know how we obey laws you know what the rules are and you kind of obey them consciously and deliberately so you see the speed limits and you look at your speedometer and you if you if you're minded to obey the traffic laws you put your foot on the brake if you're going a bit too fast that's definitely not what's going on when you drop your cup of coffee and it falls to the ground or when subatomic particles or cannonballs or whatever they are obey the laws of physics they don't have minds they don't know what the laws are they can't decide to do what the laws say or not so me and I'm kind of a human so I don't like sort of deep deeply puzzling metaphysical features of reality um I find the idea that laws of nature of prescriptive kind of completely mysterious the idea that there are bayed that they're things that govern what happens in the universe because I just can't see a way of making really good sense of that idea so me I'm inclined to think that the laws just are ways of encoding the regularities and that's all they are so to get back to the question which was are the laws eternal features at the universe or might they be human constructs well encoding the regularities is something that we do not me personally InDinero do so in some sense yes they are human constructs but the regularities that we're encoding they're not human constructs they're out there independently of us so in a sense no they're not human constructs so in classic philosophers style my answer to the question is yes and you see I thought you thought I was just being funny okay clear law would be something that cannot be disobeyed like if it gravity is a law this paper can't just ever decide not to fall where the regularity it just means that it could decide not to it just up till now it always has you have opened a massive can of worms yes I think we should be modest in claiming that we know how the laws of nature work and this isn't that we're very far away from that what we are doing in practice is all we can do is we make observations we do it as best as we can and then we write down the regularities that we see explain much of that we find all the all the peculiar features that that we can attach to the object we see to make them behave the way we see them behaving such as a laws of gravity which are massless laws that tell you the things seem to attract each other there's a cosmological constant that somehow seems to make things repelled away from each other and there are the motherís laws of quantum mechanics where in a previous discussion we discussed where these laws are really iron but they say the eye or whether they're only our perception of what they say they are and I believe the latter that models of nature are very much the way we perceive the laws of nature but that reality may be a lot more complicated and not yet within sight I think but all together these things form the laws of universe and are very important questions about them for instance how big actually is universe what are the boundary conditions of the universe is there a boundary con at the universe or not the universe split up in many other universes further away even then the first things you can see all these questions one can ask but not so easily answer unless you have a model so we are fond of making models to use them all the time but I claims that my claim is that we are still very far from the tools with our models we are just catching the surface all the laws of nature and there's also a question which is going to be asked is how permanent artists are these laws do they change at all well there's one important thing to remember if you think that laws of nature depend on space and time also and there was one important physicist actually thought that that was Paul Dirac beautiful theory where it says the only way to explain why nature so company it's a who gradually more and more complicated but the laws of nature during the Big Bang were very simple and then they evolved and became and generated large numbers just as a function of time that you could believe but if you believe such a thing then you have to say how good the laws of nature change if you go from place to place or if you go for earlier to later times how do most of nature evolve well the only way to handle that is to introduce a kind of field which I'd call a scalar field that says if the field has this value then the laws of nature such as such that maybe one there may be many of such fields but you're making your life hell of a lot more complicated than it already is without such fields so the first thing we should assume as humans is that the laws that we deciphered so far must be constant until further notice maybe you'll discover that things change okay in that case you'll have to modify our our understanding loss but these modifications will be very complicated you have new fields and then we have to ask what are the equations of those fields once you have those equations of Francis the scalar field then you're back at square one then the total combination laws of physics is again the same everywhere and then again you can ask is it really the same and you go on for it like it's forever you never reach an end point so my bet is the laws of nature that we discovered so far will be the end of the line there's no reason assume that they depend on other fields which depend on space and time again because if you start that early you'll never end so but this is a just a gut feeling I may be wrong and if I'm wrong I want people to show that to me where I'm wrong and where it is shown that nature's more complicated than you really think okay so there are laws but our version are models of them maybe still fire from the toes but there are closer to it and anything else we know about okay so Laura what do you think I agree with what it said and we would really don't it is a hard question and and we don't understand enough about it so whatever I say it's my thinking and it's speculation more than anything but in terms of the laws of nature making reference for something eternal is reference to time so I find that difficult to follow because I think laws of nature are fundamental independently of space and time on an utterly perplexing [Music]

Channel: The Institute of Art and Ideas

Views: 16,216

Keywords: the laws of the universe, the laws of thermodynamics, the laws of the sun, philosophy for our times, iai, how the light gets in festival, theory of everything, gravity, multiverse, string theory, multiverse theory, nobel prize winning, bbc, new scientist, discovery channel, philosophy, science, debate, politics, art

Id: _RX9YqyGcP4

Length: 10min 10sec (610 seconds)

Published: Wed Oct 31 2018