Forgot your password?
typodupeerror
Science

Hawking: No 'Theory of Everything' 465

Posted by CmdrTaco
from the you-all-been-punked dept.
Flash Modin writes "In a Scientific American essay based on their new book A Grand Design, Stephen Hawking and Leonard Mlodinow are now claiming physicists may never find a theory of everything. Instead, they propose a 'family of interconnected theories' might emerge, with each describing a certain reality under specific conditions. The claim is a reversal for Hawking, who claimed in 1980 that there would be a unified theory by the turn of the century."
This discussion has been archived. No new comments can be posted.

Hawking: No 'Theory of Everything'

Comments Filter:
  • The hand of Godel? (Score:3, Interesting)

    by Hatta (162192) on Thursday September 30, 2010 @02:00PM (#33750964) Journal

    Godel proved that all formal systems are either incomplete or inconsistent. Perhaps that's what we're dealing with here.

    • by abigor (540274) on Thursday September 30, 2010 @02:10PM (#33751104)

      Godel used the term "formal system" to specifically mean a recursive axiomatic system that can do arithmetic. I don't think it really applies here.

      • by Hatta (162192) on Thursday September 30, 2010 @03:25PM (#33752246) Journal

        Aren't the laws of physics axioms for the universe? Isn't the idea behind a grand unified theory to find one or two simple mathematical expressions (axioms) from which the rest of the universe can be derived? The universe is clearly Turing complete, so I really don't see how it wouldn't apply.

        • by Abcd1234 (188840) on Thursday September 30, 2010 @04:09PM (#33752890) Homepage

          Because you don't understand Godel's theorem, which is grossly misunderstood by basically everyone who's ever heard of it colloquially. Here, have a little read [scientopia.org] on how it's so wonderfully misunderstood, and so horribly misapplied.

        • by Goldsmith (561202) on Thursday September 30, 2010 @06:55PM (#33754484)

          I don't know Godel as well as some other people here, but I do know physics and you're making a lot of assumptions there, starting with that the universe can be "derived" from a theory of everything. The name is a little unfortunate, but the goal of a theory of everything is to create a unified description of the fundamental forces, not a program to simulate the entire universe. If you wanted to simply say "the theory of everything won't be able to tell you absolutely everything about every particle in the universe," you'd be right, and probably that's where you're going with your incompleteness thing.

          More fundamentally though, you're assuming the universe is a logical system. From a physicists point of view, it is a happy coincidence that rigorous mathematics is useful in describing the universe, but there is nothing that demands that this is the case (more practically: we're happy in physics to have assumptions about things like causality and time invariance, where needed).

          This may sound crazy to most people, but why exactly mathematics has been so successful in physics is still a subject of debate among physicists: whether mathematics approximates an ultimately imperfect physical reality or mathematics *is* physical reality. I don't think it will be settled soon.

        • Re: (Score:3, Interesting)

          by FrangoAssado (561740)

          Here is a way it could possibly not apply.

          Your argument seems to be this (please correct me if I'm misrepresenting it):

          Take the formal system of the "theory of everything", call it TOE. By Godel's theorem, there exists a certain arithmetic statement (G) that is independent of TOE. Because the universe is Turing complete, it's possible to physically build a Turing machine (M) whose output (or, even better, whether it halts or not) depends on the truth value of G. Since G is undecidable in TOE, the "theory of

    • by Cyberax (705495) on Thursday September 30, 2010 @02:16PM (#33751182)

      You forget important addition to Goedel's theorem. Namely: "all philosophical consequences of Godel's theorem are bunk" (including this one).

      Regarding your comment: there ARE complete and consistent formal systems. For example, real number theory is complete.

      You can't have consistent, complete system if it's _complex_ _enough_ to describe integers.

      • by Guignol (159087)
        What are you talking about ?
        "all philosophical consequences of Godel's theorem are bunk" sounds fair but as you state probably falls in the undecidable set of assertions :)
        but "real number theory is complete" ? are you confusing the "Gödel completeness" with the "Set completeness" (in the way that all Cauchy sequences are convergent in the same Set (unlike, say, rational numbers)) ?
    • by w0mprat (1317953) on Thursday September 30, 2010 @02:30PM (#33751396)
      We work on the assumption that the laws of physics are perfect and complete, and we are just trying to reveal them. The laws of physics could work well enough but actually be incomplete and consistent as you point out. They could even bebe crappy, bloated and buggy with lots of missing chunks, unused bloat and even errors.

      If the laws of physics emerged naturally, for example budding off from a parent universe, and subject to a process of evolution I would expect theories of everything to be 'just good enough' and barely work rather than somehow perfect and elegant and mystical. Much like the junk DNA, apendix and mens nipples that rides along with us because evolution didn't really have pressure need to get rid of them.

      I would say we should by default expect a theory of everything a whole basket of seemingly clumsy unweildy theories that barely fit together - after all they only need to be just good enough for us to be here and not any better. If we expect flawless elegant unified symmetry and beauty, then we'd need to demonstrate why (without invoking God to explain etc).

      Researchers have been seduced by subjectively elegant and simple equations all the way back to F=MA ... these worked well enough, but were ultimately wrong, the truth was more complex and nuanced, but now we're finding the universe is fuzzy, clumsy and possibly buggy (inflation, possible variations in c, other weirdness).
  • Oblig (Score:4, Funny)

    by gmuslera (3436) on Thursday September 30, 2010 @02:05PM (#33751016) Homepage Journal
    xkcd [xkcd.com]
  • by Culture20 (968837) on Thursday September 30, 2010 @02:06PM (#33751030)
    "The claim is a reversal for Hawking, who claimed in 1980 that there would be a unified theory by the turn of the century."

    I think the turn of the century reversed his claim for him.
    • Feh, the next thing you are going to tell me is that Linux won't work with 48 or more cores!
      • Re: (Score:3, Informative)

        by rubycodez (864176)

        it will by the turn of the century. the 22nd century will be the century of Linux on the dozens-of-cores desktop.

    • by NotBorg (829820)

      There's a Soviet Russia joke in there somewhere.

    • Did he specify which century?
    • Re: (Score:3, Interesting)

      by jd (1658)

      Actually, no. I was at the talk and he actually stated that every time people predicted the end of physics, something new was discovered that revolutionized the field; that in this light he was going to predict the end of physics and the discovery of a theory of everything. As far as I'm concerned, he has achieved his objective. Something new has indeed been discovered and it does appear to have revolutionized the field.

      To those who think Hawking is beyond his prime, I'll say maybe. No scientist likes to gi

    • Re: (Score:3, Funny)

      by dkleinsc (563838)

      It depends how fast he was moving relative to the calendar he was referring to.

  • Past His Prime (Score:3, Insightful)

    by Wannabe Code Monkey (638617) on Thursday September 30, 2010 @02:08PM (#33751068)

    I certainly hate to say it. And I certainly don't think I'm any smarter. But, Hawking is past his prime. It seems like he's been saying stuff recently just to say stuff. Maybe it's for attention, maybe it's because he knows extraordinary claims will sell headlines and his books/documentaries, or maybe it's because he actually believes in them. However, after his comments on active SETI being dangerous and now this... I don't know, it's like watching an amazing baseball player, past his prime, coaching a crappy minor league team. It's hard to criticize because I was never as good as he, and even now I couldn't manage a Denny's, but I don't really want to watch him either.

    • by amicusNYCL (1538833) on Thursday September 30, 2010 @02:13PM (#33751134)

      It seems like he's been saying stuff recently just to say stuff.

      Totally. He just likes to hear his own voice.

      • Re:Past His Prime (Score:5, Interesting)

        by Wannabe Code Monkey (638617) on Thursday September 30, 2010 @02:17PM (#33751188)

        Totally. He just likes to hear his own voice.

        Now you're making me wish that I hadn't commented in this discussion just so I could mod you up. Although if I had never commented, then you wouldn't have been able to reply to me and I wouldn't have been able to mod you up anyway. Maybe some smart scientist could help us out with this paradox.

        • by smooth wombat (796938) on Thursday September 30, 2010 @02:38PM (#33751522) Homepage Journal

          Just invent a one-way time machine. Then you could mate with all the women you wanted when men become scarce (after the giraffes have long since ceased to rule the planet) then move forward in time, wait for the last photon to decay, see the Big Bang take place, take a potshot at Hitler and as the current time approaches, slow down enough to see the comments appearing, wait for someone else to make the joke then mod them up!

          Of course you have to hope this universe isn't 10' higher than the previous universe.

    • Re:Past His Prime (Score:5, Insightful)

      by interkin3tic (1469267) on Thursday September 30, 2010 @02:20PM (#33751228)

      It happens. James Watson, who was part of the team that discovered the structure of DNA, has been saying crazier things for years. [wikipedia.org]

      My favorite was his presentation on why men liked butts. Certainly funnier than his comments on race.

      Scientists sometimes don't age well. We probably age better on average than rock stars, but then again people pay don't take what rock stars say as seriously as scientists.

    • by mwvdlee (775178)

      Is seems that the prime for any prodigal scientist is somewhere between the age of 20-30.

      Exceptions to this rule certainly exists, but most of the well-known scientists produced their best work somewhere around that age.

      Not just prodigal scientist, but pretty much all of humanity has their "creative" peak at that time, it just shows a lot more with the exceptionally gifted.

      Regarding Hawking specifically, it seems rather unlikely that he can keep up with more recent science considering his disabilities; read

    • by blair1q (305137)

      he was making a joke about SETI

      in this, he's reflecting on the fact that from what he knows about GUTE, he doesn't know if there's a way to get there from here, and he thinks he knows there's no way to get there from here

    • Re: (Score:3, Insightful)

      by deodiaus2 (980169)
      The comment about Hawkins being past his prime is really ugly, especially coming from you. I think Hawkins is honest enough to say that he does not know or understand something if he doesn't. Hawkins refered to himself as being lazy in his early years in college, so he does admit some of his shortcomings. Ronnie Reagan was often ignorant of the facts, but he said them with such conviction that even people who knew had to go back to check their references before retorting. We survived Ronnie, so I'm more
    • by qoncept (599709)
      For a scientist, Hawking sure has been making a lot of grandoise claims without a lick of evidence. What blows my mind is that people keep reporting on them.
    • Re:Past His Prime (Score:5, Informative)

      by mcgrew (92797) * on Thursday September 30, 2010 @02:55PM (#33751778) Homepage Journal

      But, Hawking is past his prime.

      He's only ten years older than me, kid. He's a physicist, not a football player. Unless you get alzheimer's or drink a lot or play high impact sports (boxing or non-US football) your brain doesn't suffer much if any.

      Like one of my old college profs was fond of saying, "kid, I've forgotten more than you've ever learned".

      However, after his comments on active SETI being dangerous

      I agree with him about that. Actively hunting for species that make us look like chimpanzes by comparison doesn't seem like the smartest thing we can do.

      coaching a crappy minor league team

      I'd say that research at Cambrige is hardly equivalent to coaching a crappy minor league team. And the list of his accomplishments puts your "past his prime" into perspective (see the wikipedia article on him):

      1975 Eddington Medal
      1976 Hughes Medal of the Royal Society
      1979 Albert Einstein Medal
      1981 Franklin Medal
      1982 Order of the British Empire (Commander)
      1985 Gold Medal of the Royal Astronomical Society
      1986 Member of the Pontifical Academy of Sciences
      1988 Wolf Prize in Physics
      1989 Prince of Asturias Awards in Concord
      1989 Companion of Honour
      1999 Julius Edgar Lilienfeld Prize of the American Physical Society[45]
      2003 Michelson Morley Award of Case Western Reserve University
      2006 Copley Medal of the Royal Society[46]
      2008 Fonseca Price of the University of Santiago de Compostela[47]
      2009 Presidential Medal of Freedom, the highest civilian honour in the United States[4]

      "When I hear of Schrödinger's cat, I reach for my pistol." -- Stephen Hawking

      I think I'll change my sig...

      • Re:Past His Prime (Score:5, Insightful)

        by oldhack (1037484) on Thursday September 30, 2010 @03:07PM (#33751980)
        You're conflating blings with accomplishment. Should have listed his papers instead of awards given to him.
      • Re: (Score:3, Informative)

        He's only ten years older than me, kid. He's a physicist, not a football player. Unless you get alzheimer's or drink a lot or play high impact sports (boxing or non-US football) your brain doesn't suffer much if any.

        Lots of US football players get concussions. I don't believe that helps them.

      • Re: (Score:3, Insightful)

        by ceoyoyo (59147)

        "He's a physicist, not a football player."

        Theoretical physics is very much a young man's game, probably even more so than football. Lederman has a good quote in his book. Unfortunately I can't remember exactly what it is, or who said it, but it involves physicists who are in their late twenties being over the hill.

        When physicists get older they become administrators and mentors. Important jobs, but not the breakthrough stuff the young ones are known for.

  • Wisdom from DS9 (Score:5, Insightful)

    by MBGMorden (803437) on Thursday September 30, 2010 @02:09PM (#33751086)

    I'm reminded of a scene from DS9. Sure it's fiction, but it always held some sway with me:

    Bashir: "Trevean was right. There is no cure. The Dominion made sure of that. But I was so arrogant, I thought I could find one in a week!"
    Jadzia: "Maybe it was arrogant to think that. But it's even more arrogant to think there isn't a cure just because you couldn't find it."

    Hawking a smart guy, but he by no means knows everything. Throwing in the towel and declaring that there is no right answer simply because he hasn't found it just doesn't hold much water with me. We might not figure it out for 100 years. We might figure it out tomorrow. We might NEVER figure it out, but simple logic says that there is a unified equation. It might not be simple or pretty, but if the universe operates on a consistent set of physical laws, it's out there.

    • Wouldn't be neat if it turns out to be something like a DNA string with certain parts inert for different scales of measure?
    • Although I expect there is a unified equation, I don't see how simple logic says any such thing (not without the argument also being easily overturned). At best, incredibly complicated logic says that, but I'm not convinced that's even true.

    • Re:Wisdom from DS9 (Score:5, Insightful)

      by electron sponge (1758814) on Thursday September 30, 2010 @02:22PM (#33751250)
      "The universe is not required to be in perfect harmony with human ambition." - Carl Sagan
    • Re:Wisdom from DS9 (Score:5, Insightful)

      by guyminuslife (1349809) on Thursday September 30, 2010 @02:22PM (#33751256)
      Simple logic says a lot of things, some of which it turns out are not true.
    • by euxneks (516538)

      [...]but simple logic says that there is a unified equation.

      Can you elaborate? The only thing I can think of is a bigger "Game of Life" type thing... Is that what you mean? Seeming complexity from simple equations?

    • Saying that we may never find a TOE no more means that everyone should stop looking for one than saying we would find one before the turn of the century means everyone who wasn't looking one should stop what they were doing.

      Both of Hawkings' statements were based on where he saw physics heading at the time. He was confident that we would find a TOE, and now he thinks that we may not.

      Either way, physicists are going to continue to make theories, predictions, and observations and try to match them. They will

    • Re:Wisdom from DS9 (Score:5, Insightful)

      by MortimerGraves (828374) on Thursday September 30, 2010 @02:45PM (#33751626)

      I wonder if it may be an example of Clarke's First Law:

      "When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is probably wrong."

  • by RobinEggs (1453925) on Thursday September 30, 2010 @02:10PM (#33751092)

    Instead, they propose a "family of interconnected theories" might emerge

    Which, if you read them all at the same sitting and follow all the connections, just might read like one big...unified theory.

    This seems very, very close to a distinction without a difference.

    • by onionman (975962) on Thursday September 30, 2010 @02:31PM (#33751414)

      Instead, they propose a "family of interconnected theories" might emerge

      Which, if you read them all at the same sitting and follow all the connections, just might read like one big...unified theory.

      This seems very, very close to a distinction without a difference.

      No, there is a very important difference. Hawking is stating that there may be "locally everywhere solutions" without a "global solution." This is a very important concept in advanced mathematics. Go read about the mathematical terms "sheaf" and "local-global principle."

      Hawking is essentially saying that there very well may not be one single theory which explains everything. Instead, there may be a bunch of theories, each of which is valid only in certain areas, and which agree with one another where they overlap, even without a global solution.

      For a simple example which many readers may already be familiar with, consider the complex logarithm (e.g. the natural log on the complex numbers). To make it well defined, you must make a "branch cut" and decide which branch you want to take. Different branches agree where they overlap, but there is no single global solutions... just a patchwork of solutions that agree where needed (blah, blah lift to a covering space). Pick up a book on complex analysis for details.

  • by RyanFenton (230700) on Thursday September 30, 2010 @02:13PM (#33751126)

    I don't actually mind if this is the case. What it means then, is that new properties of aggregated matter emerge as you go up, and up in scope and scale, and that there does not have to be a set relationship on what rules must emerge.

    Other than aesthetics, those emergent rules don't have to carry a thread of logic visible at all scopes. Rather, you just need to have the large number of interactions actually occur in relationship to eachother to see the combined effect, with many aspects unforeseeable by only observing the elements many magnitudes smaller.

    Whether this might make the universe a more or less beautiful puzzle to figure out is open to interpretation.

    Ryan Fenton

    • Everyone should read RyanFenton's post. This is a beautiful and deep analysis and, while it may be true or false, is a reasonable way to reconcile the current state of art.

      Nicely done sir. I will ponder your words for weeks to come. A post like this can lift my entire assessment of humanity.
    • Re: (Score:2, Interesting)

      by entrigant (233266)

      Correct me if I'm wrong, but isn't the very idea of emergent phenomenon the result of a complex system emerging from less complex interactions? I was always under the impression the idea of a "theory of everything" is to isolate those simple interactions that all emergent behavior stems with the idea being that perhaps, in time, the emergent behavior can be predicted or even constructed.

      Perhaps emergence can go both ways.. somehow? There is no base set of rules, and no matter how far in either direction you

  • by Theory of Everything (696787) on Thursday September 30, 2010 @02:13PM (#33751136)

    I'm right here. I promise I do exist. Really.

  • Just a result of age (Score:4, Interesting)

    by Troggie87 (1579051) on Thursday September 30, 2010 @02:15PM (#33751160)

    As scientists age they become somewhat jaded, it happens to a lot of people. Hawking has seen a problem he thought was about to be solved get ever more complex while little new progress has been made. I don't blame him for changing his stance. I had a professor during my undergrad who had been a part of some of the first fusion research, and he would occasionally bring up that he didn't think it was possible. According to him, "the kids today are trying what we tried and couldn't get to work back then" (Paraphrased). Maybe doubting there is a solution to the problems you have struggled with all your life is the best way to find peace as your life winds down?

    Oh, on a personal opinion note, I doubt we will ever find a *provable* theory of everything. Eventually someone will put together something that relates a lot of complex fields, but I suspect it will be something ad hoc and beyond the practical limits of humanity to test. (*cough* string theory variant *cough*)

    • by jschen (1249578)

      Oh, on a personal opinion note, I doubt we will ever find a *provable* theory of everything. Eventually someone will put together something that relates a lot of complex fields, but I suspect it will be something ad hoc and beyond the practical limits of humanity to test. (*cough* string theory variant *cough*)

      One can never prove a theory of everything, but one can validate the theory against all observables. If multiple theories emerge, all of which satisfy everything observed, then I would favor the simplest one (hopefully not a theory with more variables than there are atoms in the universe). Furthermore, the more complex one must predict something different from the simpler one, or else they would be fundamentally the same. So that would lead to a testable hypothesis to choose between different theories of ev

  • Gogol Bordello has the good doctor beat then: http://www.youtube.com/watch?v=jFBTmclJrto [youtube.com]
  • by night_flyer (453866) on Thursday September 30, 2010 @03:15PM (#33752086) Homepage

    'If we discover a complete theory, it would be the ultimate triumph of human reason - for then we should know the mind of God.' Hawkins - 1988

  • by JAZ (13084) on Thursday September 30, 2010 @03:48PM (#33752580)

    I've been watching documentaries about Dr Sheldon Cooper's work out at Caltech and I'm lead to believe that he's very close to proving String Theory as a Grand Unified Theory.

    Surely, Professor Hawking is aware of this research?

  • by MpVpRb (1423381) on Thursday September 30, 2010 @03:56PM (#33752714)
    When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong
  • by PerlHeadJax (614572) on Thursday September 30, 2010 @08:05PM (#33754878)
    From Gleick's "Genius: The Life and Science of Richard Feynman"...

    "'People say to me, "Are you looking for the ultimate laws of physics?" No, I'm not...If it turns out there is a simple ultimate law which explains everything, so be it--that would be very nice to discover. If it turns out it's like an onion with millions of layers...then that's the way it is.' He believed that his colleagues were claiming more success at unification than they had achived--that disparate theories had been pasted together tenuously. When Hawking said, 'We may now be near the end of the search for the ultimate laws of nature,' many particle physicists agreed. But Feynman did not. 'I've had a lifetime of that,' he said on another occasion. 'I've had a lifetime of people who believe that the answer is just around the corner.... But again and again it's been a failure. Eddington, who thought that with the theory of electrons and quantum mechanics everything was going to be simple...Einstein, who thought that he had a unified thoeiry just around the corner but didn't know anything about nuclei and was unable of course to guess it...People think the're very close to the answer, but I don't think so....

    Whether or not nature has an ultimate, simple, unified, beautiful form is an open question, and I don't want to say either way.'"

    (From the epilogue of the book, pp. 432-433, emph. added.)

Lo! Men have become the tool of their tools. -- Henry David Thoreau

Working...