What Are You Optimistic About?

Every year John Brockman’s Edge Foundation asks a large number of people in science and technology to write a short piece answering a chosen question, and this year the question is What Are You Optimistic About?

Among particle physicists, the overwhelming thing to be optimistic about is the LHC. For instance, Lawrence Krauss writes:

I am optimistic that after almost 30 years of sensory deprivation in the field of particle physics, during which much hallucination (eg. string theory) has occurred by theorists, within 3 years, following the commissioning next year of the Large Hadron Collider in Geneva, we will finally obtain empirical data that will drive forward our understanding of the fundamental structure of nature, its forces, and of space and time.

Others who also mention the LHC include Lisa Randall, Charles Seife, Lee Smolin, Adam Bly, Maria Spiropulu, Karl Sabbagh, Frank Wilczek, Paul Steinhardt and Corey Powell.

Wilczek describes himself as optimistic that “physics will not achieve a theory of everything”, taking the point of view that he hopes nature will continue to surprise us. He also denigrates the search for a fundamental theory of everything by noting what it has led to in the case of the string theory landscape:

At this point the contrast between the grandeur of the words “Theory of Everything” and the meager information delivered becomes grotesque.

Alexander Vilenkin on the other hand is optimistic about the multiverse and the anthropic landscape, saying it is implied by string theory, “our best candidate for the fundamental theory of nature”, and that he thinks that statistical predictions will be possible.

The person I agree with most is Gino Segre who writes:

So why am I optimistic? Because I believe that controversy, with clearly drawn out opposing positions, galvanizes both sides to refine their opinions, creates excitement in the field for the participants, stimulates new ideas, attracts new thinkers to the fray and finally because it provides the public at large with an entrée into the world of science at the highest level, exhibiting for them heated arguments between great minds differing on questions vital to them. What could be more exciting?

That sort of optimistic point of view on the whole string theory controversy is one that I hope more theoretical physicists will take, with string theorists acknowledging that there are serious questions that have been raised and that are worth debating.

Personally I’m a lot more optimistic now than I was a year ago that a more realistic view of string theory has started to take hold in many quarters, and that perhaps particle theory will move towards a healthier state. Like the Edge contributors, I see the fact that the LHC is now not far off as a cause for optimism. Perhaps it will produce the sort of surprising new insight into electroweak symmetry breaking needed to show the way forward. Even if it doesn’t do this, the likely failure to see superpartners or extra dimensions may encourage theorists to give up on ideas that don’t work and try and strike out in other directions.

This entry was posted in Uncategorized. Bookmark the permalink.

28 Responses to What Are You Optimistic About?

  1. mclaren says:

    With minds like this on the job, there’s every reason to be optimistic about string theory:

  2. Renormalized says:

    That story from the onion has been floating around the internet for 5 years and was totally fabricated by a student.

  3. hack says:

    A fabricated article in the Onion? Say it isn’t so!

  4. Tony Smith says:

    In his 2007 Edge answer to “What Are You Optimistic About?”, Steve Grand said:

    “… The Strong Possibility That We’ve Got Everything Horribly Wrong

    The thing I’m most optimistic about is the strong possibility that we’ve got everything horribly wrong. All of it. Badly. …

    Sometimes we manage to convince ourselves that we have a handle on what is going on, when in fact we’re just turning a blind eye to a mass of contradictory information. We discard it or ignore it (or can’t get funded to look at it) because we don’t understand it. It seems to make no sense, and it can take us a while before we realize that the problem doesn’t lie with the facts but with our assumptions. Paradigm shifts are wonderful things. Suddenly the mists clear, the sun comes out and we exclaim a collective “aha!” as everything begins to make sense. What makes me so optimistic about science right now is that there are plenty of these “aha” moments waiting in the wings, ready to burst energetically onto the stage. We’ve got so much completely wrong … and I think a lot of our standing ideas and assumptions about the world are about to turn inside-out, just as our much older, religious ideas did during the Enlightenment.

    My guesses for prime candidates would include quantum theory and our understanding of matter, but those aren’t my field …

    My field is artificial intelligence, but I’m sad to say that this subject started on the wrong page of the map many years ago and most of us haven’t woken up to it yet. We keep our eyes firmly on the route and try not to look to left or right for fear of what we might see. … the digital computer has dominated the AI paradigm, through failure after dismal failure. …”.

    I suggest that Steve Grand’s selection of “quantum theory” as a “prime candidate” may be accurate,
    that the last paragraph in the quote from him would be just as accurate if
    “artificial intelligence” were changed to “quantum theory”
    “the digital computer” were changed to “superstring theory”
    “the AI paradigm” were changed to “the high-energy theoretical physics paradigm”.

    It would be interesting to compare the sociology of theoretical physics and of AI studies over the past couple of decades or so.

    Tony Smith

  5. normalized says:

    There is no cause for optimism. People shouldn’t go into science if they’re prejudiced, because nature doesn’t conform to most prejudices. Ideally to the mainstream of the 19th century, the geological record should have turned out to support Biblical Creationism. It didn’t. Tragic for all those mainstream guys.

    String theory is insulated too well to be disproved directly, but if the predictions of an alternative theory were confirmed, then that would make string theory look a waste of time. Even though string theory can’t be disproved, it would be discredited.

    Therefore, it is guaranteed that all alternatives that might make contact with reality will be attacked most strongly as crackpot by the mainstream.

    Weaker alternatives, which look as pathetic as string theory regarding experimental falsification, will be looked at slightly more tolerantly by the mainstream.

    Similarly, lame attacks on string theory will be tolerated but convincing attacks will be answered with strong abuse. There is no way anything can improve. What if people don’t like nature? Suppose string theory turns out wrong. What will stringers do? Call nature ‘crackpot’ and storm off in a huff? Obviously, they want to postpone that evil day indefinitely.

  6. Michael says:


    With the LHC about to begin its first run, and supposing that both the Higgs boson and superpartners are discovered, respectively, what then would theoretical physics look like for the next few years?

    Answer, anyone?

  7. Ari Heikkinen says:

    Or, it could turn out that LHC does nothing but make the widely adobted we-need-a-bigger-accelerator syndrome even stronger.

    My question about LHC is that has there ever been any realistic estimate of energies required to arrive at anything even remotely useful (I mean, worth the cost, considering the huge amounts of money these things cost to build) ?

    To me it somewhat appears that everyone’s just guessing and no one even knows what’s it supposed to reveal.

  8. QM says:

    Ari, that’s why research is more interesting than burocracy.

  9. nontrad says:

    Back in the day, when I was doing physics (around ’97-ish) and listened to various pros and cons of matrix / M / this and that theory bandied about in various hallways, the killjoy phrase I heard most often was ‘If LHC sees no SUSY then that’ll be it for ST ‘. Almost invariably, once that card made it to the table even the most zealous proponents tended to stare down at their shoes while the conversation turned to other matters.

    Most important for my young ears: This magic phrase didn’t come from minor weights; some of the speakers had seen more then one ‘revolution’ in their time.

    So….as far as I am concerned….based on my very limited experience….it’s ALL about LHC. ALL about LHC.

  10. Seth says:

    To Notrad: what I’ve heard, most recently, is that the LHC can’t prove String Theory and can’t kill it either. You can always move the Supersymmetry up to a higher energy scale.

    And speaking of killjoys, this isn’t the year to be optimistic about LHC. We’ll be months into 2008 before real data and analysis of energy frontier physics start to arrive.

  11. Hans says:

    In the 10 dimensional theory, ST is certainly supersymmetric. However: LHC won’t see this length scale. The compactified theory that it faces to must not be supersymmetric.

    But when SUSY is not seen at LHC, there would exist no clue at all, that ST is the correct way. “When we don’t see SUSY at LHC, then we need good advice” said Dieter Luest.

    So, LHC can’t kill ST but in can reduce remaining hopes that one can describe physics with it, which can be observed.

  12. Yatima says:

    Tony Smith says:

    It would be interesting to compare the sociology of theoretical physics and of AI studies over the past couple of decades or so.

    This has probably been done somewhere. Sociology should be similar in a general sense. There are the ‘Notable People’: Minsky comes to mind. Apparently his paper on the limits of “perceptrons” was a major fator in funding cuts for artificial neural networks. Everyone piled into symbolic computation after which some new results and disillusionment with the symbolic approach led to a revival of the ANN approach etc. There are the ‘SSC’ programs like ‘Ffth Generation’ and ‘Strategic Computing Initiative’. These yield little empirical data but generally lead to nowhere and/or mutate into something else due to changing goals and the realization that one has aimed too high.

    Thing is, the problems are of fundamentally different nature. While ThPhys pulls into the direction of an overarching and hopefully elegant/compact description, “Intelligent System Studies” (to avoid the AI moniker, which has become overly stale lately) has given up the delusion of finding ‘The Intelligence Algorithm’ a long time ago. Said delusion has been called ‘Physics Envy’ – by whom I don’t remember. Some still ride against qualia strawmen or sundry shadows in Searl’s Room or they go off orthogonally into QM or whatnot (no disrespect to Penrose intended) but this gets tiresome quickly to anyone who remembers his brain is such a polynomial kludge that the may be unable to find his own socks in the morning.

    I’m always ready to be surprised by fundamental shifts but at this point I would be surprised to be surprised if I may say so.

    A paper about the “messiness” by Cherniak. Still good:

    “Undebuggability and Cognitive Science,” Communications of the ACM, 31 (1988) 402-412

    My excuses for this digression into non-physics.

    Happy new Year to Peter Woit … and the rest of the crew.

  13. nontrad says:


    Thanks for the thoughts; see you after LHC 2007.

    Best regards,


  14. Chris W. says:

    As I recall, some time ago on Cosmic Variance JoAnne Hewett said that if the LHC doesn’t turn up something pretty interesting within a few years then experimental particle physics in the U.S. is in for some very dark days. Actually, she may have said this in a comment. Perhaps she can offer a reprise (or a correction) here…

  15. from EU says:

    some time ago there was a post at CosmicVariance about this topic, and I was very surprised in hearing that apparently everybody thinks that the past and present situation in the US is fine, that SLD had been as successful as LEP, etc. Elsewhere one hears different opinions. Let me present two facts, that can be checked

    1) A few years ago, many experimentalists in Europe didn’t like that a large number of US experimentalists joined LHC without giving a proportionally large contribution to its construction. One of the arguments in favor of this decision was the danger of a collapse of the high-energy experimental community in US before LHC.

    2) Tevatron, “the biggest accelerator in world”, actually has a circumference smaller than HERA, than LEP/LHC, than the old SppS.

  16. Michael says:

    Don’t worry if particle physics bites the dust within the next few years… there’s Financial Engineering to go into for all those out-of-work young postdocs.

  17. island says:

    Actually, she may have said this in a comment.

    In *this* forum:

    If the worst case scenario plays out, and the LHC discovers nothing, then that is the end of particle physics as we know it. And that includes string theory. They may think they are immune, but they are not – they will fall due to lack of funding with the rest of us.

    I can’t wait, because I’m fairly certain that you’ll be able to hear John Horgan’s shouts of vindication from just about anywhere on Earth.

  18. Thomas Larsson says:

    If the aether wind does not turn up in the Michelson-Morley experiment, it just means that something like split aether theory is right.

  19. Chris W. says:


    Yes! I’m sure that’s the one. Thanks for tracking it down.

  20. For a rather different “entrée into the world of science,” see page 56 of this week’s New Yorker (issue dated Jan. 8, 2007).

  21. Eli Rabett says:

    Steve I just put the NYorker cartoon up Great minds, etc…

  22. MDL says:

    I’m optimistic that someday one of these searches:

    site:http://www.math.columbia.edu/~woit/ “minimum description length”
    site:cosmicvariance.com “minimum description length”

    or one of the first ten links (I gave up after that) returned from this search:

    “string theory” “minimum description length”

    will find a discussion of the relevance of the minimum description length (MDL) principle to the issue of the scientific status of string theory. MDL is, after all, a common criterion for selecting among theories in machine learning, when all of the theories can fit all of the data.

    That discussion would likely start with the argument that — provided both theories can be made to fit all the data! — the criterion for preferring one physical over the other should be lesser size, as expressed in some reasonably primitive and unbiased representation in which all expressions can be reduced to bit strings. (See also Kolmogorov complexity.)

    Someone then would doubtless speak up and claim that MDL sidesteps objections that the use of anthropic arguments destroys scientific criteria, then someone would object that having even one real number could make complexity unbounded, and someone would respond that this suggests that comparing the number of free real-number parameters in each theory is a better basis for preference than is MDL in the conventional sense. Then I would expect to see arguments about the status of real numbers, particularly the unbounded-complexity sort, no doubt leading someone to assert that all parameters are actually rationals, citing Pythagoras.

    It will be a lot of fun to see all that, and to see where it leads. Maybe some day.

  23. J.F. Moore says:

    I can’t wait, because I’m fairly certain that you’ll be able to hear John Horgan’s shouts of vindication from just about anywhere on Earth.

    I think he is more reserved than that. For one, unless LHC science is a total bust, ILC will certainly follow, so that is another decade of pining enabled, with a couple of years for someone to win (or not) a Nobel Prize in time to resolve the Horgan-Kaku long bet:


  24. wab says:

    Let’s say that all LHC finds is a very broad HIggs at well over 500 GeV. I would not bet on an ILC in that case.

  25. Ari Heikkinen says:

    Interesting comments from Kaku on that “longbets” link. Lot’s of “if”‘s and “might”‘s tho.

  26. plank says:

    “Personally, I feel no need to prove the theory experimentally, since I believe it can be proven using pure mathematics.” (Kaku)

    Interesting indeed!

    How does one prove a theory about reality using pure mathematics?

    You may prove that it reproduces all phenomena you’ve observed by now at best. But for that there exist good theories already. So what is really needed is predicting something unknown and getting EXPERIMENTAL verification of that.

    I for one would like to know how to prove, say Newton’s laws of motion using only pure mathematics.

  27. Thomas Larsson says:

    You may prove that it reproduces all phenomena you’ve observed by now at best. But for that there exist good theories already.

    There are many interesting numbers not explained by current theories, e.g. the spectrum of particle masses.

  28. plank says:

    “There are many interesting numbers not explained by current theories, e.g. the spectrum of particle masses.”

    Right, I wasn’t precise enough. I should have written that many theories explain a lot of the data we have. Those theories are “incompatible” but they still explain a lot.

    So yes, retrodiction of unknown relations already experimentally verified, say mass ratios, mixing matrices constraints or something like that, would also be a breakthrough.

    My point is, even if your objective is explaining all that has been observed, you can’t do it with pure mathematics alone. You need experimental data in order to check that theory. And if you predict anything new, to be “sure” you need to verify that too.

    When a physicist writes “Personally, I feel no need to prove the theory experimentally, since I believe it can be proven using pure mathematics.” (and this seems like not a very uncommon idea among his peers) I think there is genuine reason to be concerned.

    I understand that theoretical physicists need to be hardheaded.
    Imagine if Galileo didn’t ignore air friction and all that! To this day we would have only Aristotelian Physics. A feather doesn’t fall like a stone. Everyone can see this on their daily experience. But, Galileo made an hypothesis (model) and verified that model experimentally with controlled conditions he though reproduced the assumptions his model made.

    You can’t expect to say that the distance of falling bodies varies with time like the sum of the first n odd integers (he did say this, because \sum_{k=1}^n (2k-1) = n^2) and expect that reality conforms to your intuitions because the fact that summing the first odd integers you get a perfect square is so beautiful.

Comments are closed.