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We all have things that keep us up at night, as we try to solve the problems in our lives. But just think of the poor physicists: They are trying to solve the problems of the Universe! At a recent physics conference at the Perimeter Institute for Theoretical Physics in Waterloo, Canada, a panel of scientists were asked what questions in physics kept them awake at night. Here are their answers:
Sean Carroll, Caltech
Why are the laws of physics the way they are?
Katherine Freese, University of Michigan
What is the universe made of?
Leo Kadanoff, University of Chicago
How does complexity develop in the universe?
Lawrence Krauss, Arizona State University
Have we come to the limits of our knowledge?
David Tong, Cambridge University
How will we ever know if string theory is correct?
Neil Turok, Director, Perimeter Institute
What happened at the singularity of the Big Bang?
Andrew White, University of Queensland
What is life?
Anton Zeilinger, University of Vienna
How far are we along the road of scientific discovery?
Gino Segrè from the University of Pennslyvania
He is concerned about the world not having enough young physicists to answer all those big questions that keep the rest of the panel awake.
Source: Physics World
What is keeping me up at night are those regularly lists of ill-posed questions that scientists are producing at quaint conferences. [The Perimeter Institute is a haven for quantum gravitation “physicists” and other mathematical and/or philosophical minded people, so I expect their conferences to be quaint. My apologies if not.] Many of those questions use to be outside their area of expertize and have been given answers already.
As an example here, quantum physicist White’s question “what is life” is known in biology to first order (because the process of life, evolution, is known) and statistical physicist Kadanoff’s question on complexity is ill-posed (as complexity is – at least outside of statistical physics – I dunno if they have a decent definition).
While I have a huge respect for all the physicists involved, unfortunately I’m sort of ill at ease with Carroll’s and Krauss/Zeilinger/Segrè questions. They are both given first order answers for a long time. (“Naturality of maximal symmetry” respectively “No.” The later is such an old and recurrent Q&A it’s like “a physics zombie” – and I’ll bet it eats brains too. o.O)
Turok is idiosyncratic since there has been no test for a singularity and there are plenty of natural alternatives. It makes him look like still rowing upstreams with his AFAIU more or less dead in the water cyclic cosmologies which have those.
Now David Tong’s question I like, it’s in his area and on the money. Kudos, that is one more sane question than those lists use to have. 😀
“regularly lists” – regularly published lists
Actually, this isn’t all that simple.
Firstly, you can, theoretically, have life without evolution. Just keep the environmental conditions absolutely unchangeable in time, and a mutation rate of zero, and you effectively stop evolution, while maintaining life going. Even if such conditions don’t exist in the ever-changing natural world, you can do that in laboratory, with is enough to prove the concept.
Secondly, we only know life as we know it. This may seem like an oxymoron, but it isn’t, because there can be other life-bearing chemistries we know nothing about. Granted, it’s highly likely, by its very nature and abundance, that most life in the Universe is based on the chemistry of carbon, but we don’t really know for a fact if that is so.
And thirdly, the boundary between living and non-living is a blurry line. Viruses, for instance, do evolve, but they can’t multiply (hence evolve) without highjacking the metabolism of other organisms. Out of other living organisms, and if their numbers are sufficient, viruses are known to form crystals, which is instrinsically a mineral way to organize matter. So, are they living or not? This has been argued endlessly in biology since their discovery, and still there is no agreement. And then there’s the prions and other self-replicating proteins…
So no, we don’t really know for sure what is life. We have good hints, but that’s all. Andrew White is right.
Crazy Eddie’s Conjecture:
“Every body of knowledge is an open set.”
and thus
“Every body of knowledge has a fringe.”
But “the perimeter institute” is a better name than “the fringe institute”
@Torbjorn Larsson: I highly recommend you swing over to the q2cfestival.com site and check out the actual video of the panel, rather than relying on the 10-words summary presented here. You seem to have either misunderstood, or completely misrepresented, the nature of the questions posed.
Take a listen to Carroll’s talk on the entropy of the universe. It is mostly rather basic stuff. However, it does make a cogent case for the multiverse towards the end. This should be listened to by those who were the most skeptical of the write up here on Linde’s paper.
LC
@Lawrence Crowell: I caught that talk by Carroll over at his Cosmic Variance site a few days back and highly recommend it. Covering, among other things, entropy and the arrow of time, it does lay out in largely nonmathematical terms an argument for multiverse cosmology.
Here’s a link to the video: http://blogs.discovermagazine.com/cosmicvariance/2009/10/19/talking-about-time/ .
@ Jorge:
“keep the environmental conditions absolutely unchangeable in time, and a mutation rate of zero, … you can do that in laboratory…”
I’m skeptical with the second condition… How can you actually build a self-replicating system that _never_ makes any mistake?
Actually, I think your points would invalid any specific definition of life (chemistry, etc), but evolution is a more general concept that doesn’t need any of these.
Besides, I think the usual virus question is irrelevant. Life is a system, viruses are part of the system, they’re a part of life.
My own question: what is consciousness?
Surprising that none of these guys went for it…
I hope there are more down to earth physicists trying to solve problems of the Earth first. Anyway they were asked what questions kept them awake at night and they answered accordingly, although some questions don’t seem to be physics related, i think. Maybe physics has a broader definition.
@ Manu
Although I ask this question myself (and have no answer, of course), I don’t think it is related to physics, as those question should (almost) be. A physicist wouldn’t stay awake for that question, because this most likely not quantifiable in terms of mathematics. This is more a question to neuro-scientists or biologists.
Btw: Poor physicists? No, not really. A physicist LOVES to think about such problems, at least I do. It is not too bad, if you can’t solve a problem, but just dealing with a problem makes a lot of fun.
Ok, I admit, it strongly depends on the problem. But such fundamental questions are not solved in one night, it is more a matter of if it will ever be solved – but thinking about the “non-solvable” things really makes a lot of fun.
@Manu
You can’t. But you can select the errors out. Nature could do it if it was advantageous (and it does to some extent, in species that are particularly cancer-resistant, like the sharks) And people can do it too. In fact, microbiologists do that all the time when preparing pure bacterial strains.
And regarding the systemic part of it, well, sunlight is also a part of the system, without it (most) life would be impossible, but you wouldn’t argue that sunlight is a living thing, would you?
Too little is known about consciousness to formulate a serious scientific question about it. This in spite of some of the metaphysical ideas about it role in quantum mechanics or cosmological conjectures about the anthropic principle.
LC
My question would be, “what is the point of it all?”
I remember reading a scifi story where consciousness was found to be another equivalent of mass-energy.
That’s an interesting concept!
“Why is there something instead of nothing?”
What is nothing?
The problem with nothing is that once you give it a name it is not exactly nothing.
LC
LC: excellent! 😀