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Approaching 50 Years of String Theory

math.columbia.edu

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Re: Approaching 50 Years of String Theory

#121

Post by dgfl »

Tadpole9181 wrote: post #119
dgfl wrote: post #82

Earlier quoted context omitted.

You may be understating how much 15 orders of magnitude are. The only truly exponential technological progress we’ve ever had, transistors, only scaled by ~5 orders of magnitude in feature size. Thermal engines went from maybe 0.1% to ~50%, less than 3 orders of magnitude, in about 200 years. There’s very fundamental physical laws that suggest that engines are done, and transistor scaling as we have known it for 30 y…

Are you seriously insinuating that string physics are asking for this collider you alone entirely made up? As if people who actually do study string theory are too stupid to know primary school math and this criticism is somehow high-brow and novel? Not to mention you entirely missed the point of what I said. There is research into the most niche, useless fields imaginable, because not every endeavor taken by every h…

I didn’t make it up, it’s a well known talking point around string theory. I think it was first mentioned by a practicing string theorist. Of course it’s not a novel critique, but I’ve read about putting data centers in space on this website, so I think it’s worth trying to teach people how to do these sort of Fermi problems quickly.

I did indeed miss your point, it was well hidden under a lot of sarcasm. I think it is of course completely valid. People should be free to research what they want, and I’m sure string theory must be beautiful mathematics.

But if your goal is unifying QM and GR, and/or achieving a theory of everything (as is for most theoretical physicists), then me and a growing fraction of physicists think that it’s not a promising avenue. I’m not advocating for only working on “useful” things, because such a theory is not likely to yield much profit to anyone in the foreseeable future anyway. But if you state that a unifying theory is your goal and seek funding for that goal, then string theory should move to the backstage. The mathematics department would rightfully be happy to house you otherwise.

Re: Approaching 50 Years of String Theory

#123

Post by tim333 »

tlogan wrote: post #65
gnfargbl wrote: post #50

People often say that the problem with string theory is that it doesn't make any prediction, but that's not quite right: the problem is that it can make almost any prediction you want it to make. It is really less of a "theory" in its own right and more of a mathematical framework for constructing theories. One day some unusual observation will come along from somewhere, and that will be the loose end that allows som…

I am old enough to remember when string theory was expected to explain and unify all forces and predict everything. Sadly, it failed to deliver on that promise. And there is no known single real world experiment that can rule out string theory while keeping general relativity and quantum mechanics intact. More accurately, string theory is not wrong (because it just cannot be wrong). Because it does not predict anythi…

You can't really show it's wrong because there are dozens of different theories but using the Wikipedia definition "point-like particles of particle physics are replaced by one-dimensional objects called strings" it's possible that particles are not strings. I guess it would then be like fairies at the end of the garden theory. Good from a literary fiction point of view but not reality.

Re: Approaching 50 Years of String Theory

#124

Post by tejohnso »

20k wrote: post #45
tejohnso wrote: post #27

Earlier quoted context omitted.

I thought her rant about bullshit papers was pretty convincing and poignant.

The problem with sabine is that she's become the worst person to make a correct point for the wrong reasons If you do research it becomes pretty apparent that a high number papers are not great. There's varying issues, but a big one is that the funding model incentivises pumping out papers which are often of low quality, researching whatever happens to be in vogue at the moment Literally everyone I've ever talked to…

Your paragraphs two, three and four are exactly what Sabine is communicating. So much so that it almost sounds like you pulled a transcript from one of her videos.

I don't think you're describing "the" problem with Sabine. She's not what you want her to be but that's a you problem. You're describing your particular problem with Sabine.

I appreciate that she's doing a lot to bring attention to the real issue despite your claim that she is supporting grim figures. I know about the problem because of her work, but I have no idea who Ben goldacre is.

Also no idea what you mean by supporting grim figures. I checked to see if she has come out in support of Jeffrey Epstein or something crazy like that, but no.

Re: Approaching 50 Years of String Theory

#125

Post by tim333 »

ajkjk wrote: post #100
tim333 wrote: post #78

Earlier quoted context omitted.

Even so I don't get how electrons a meter apart interact through that stuff, as opposed to the electrical fields which spread out through space and so interact with other electrons as featured in quantum field theory which is what physicists use to actually calculate physical results, as opposed to string theory which fails to calculate actual physical results. "if you cut down the spatial dimensions to just 1D" does…

The string theory model is structured from the start to reproduce existing theories as a consequence, so the problem here is a lack of understanding on your part rather than a mistake in the theory. I do suspect that most people who are working on this stuff (or any stuff for that matter) don't think very hard about the basic phenomenological claims to the point where they can explain them well. In particular your mo…

I can definitely buy a lack of understanding on my part - my understanding of all this is quite fuzzy. But I'm not sure string theories reproduce existing theories so much a say this is compatible with the other stuff in a handwavy way? I don't think there's any "we assume strings and thus can deduce quantum mechanics and general relativity" stuff? I don't think anyone can deduce quantum mechanics and Einstein's deductions with relativity are based on simple observations like the speed of light being observed to be constant and acceleration seeming similar to gravity?

Re: Approaching 50 Years of String Theory

#126

Post by snapplebobapple »

karmakurtisaani wrote: post #70
snapplebobapple wrote: post #60

Earlier quoted context omitted.

you are mixing up gambling spend vs whole industry spend. If string theory was a small handful of people making up a small m*nority of physics departments like non-euclidea geometry research was that would be fine. Its huge swaths of most physics departments and a huge suck on research funding. For that kind of spend you better show results because you are in production phase at that point not lotto ticket moonshit p…

> m*nority Is this a typo? I see a lot of words being censored these days and I assumed it's because of some algorithms and visibility. That shouldn't be the case here tho..

Its a spelling mistake from responding from my phone because my life is busy...

Re: Approaching 50 Years of String Theory

#127

Post by snapplebobapple »

boznz wrote: post #84
Tadpole9181 wrote: post #68

Earlier quoted context omitted.

I think you are vastly overestimating the number of string physicists and how much their non-experimental research costs. There's maybe a couple or few hundred-ish in the whole world that focus on it. And they don't need much money because it's pretty much all math.

As a percentage of theoretical physicists it is probably significant though. A Better question is how much love/money/attention is going into rival theories ?

It is basically this. People arguing for string theory have no concept of how to maximize return with uncertainty. The thing had 50 years of substantial funding and substantial mindshare and pushed us nowhere. Any rational person with basic risk understanding would know at this point its a fail and we are in the not knowing what to pursue phase so we should be supporting small investments in dicerse options &ntil something promising happens then we can concentrate funding there &ntil that times out or gices us the understanding to achieve something new and great. The lifecycle of increasingly aupporting string theory s=ould have turned 2 to 3 decades ago instead of just recently. We lost atleast 20 and more like 30 years of progress we didnt have because a bunch of very smart people captured the physics funding aparatus to enrich thselves.

Re: Approaching 50 Years of String Theory

#128

Post by mishaevtikhiev »

nsoonhui wrote: post #111
mishaevtikhiev wrote: post #102

I have a PhD in high energy theoretical physics (hep-th for short) and I've written a paper on string theory, so I'd like to comment on some things: 1. I think there are two reasons why string theory is cool (other people may have different opinions). Please note that none of these two reasons are directly related to the extension of Standard Model. 1.1. String theory is the only theory so far that can mix gravity an…

Thanks for the comment that exposes the nuances. As a non physicist who is interested in physics, I would say that the predicament is that we simply don't have enough data to tell how to improve our physics theory, but we have too many physicist working in the field, so ideas just get staled. Is that a correct assessment?

Not exactly, I'd put it as follows: 1. In phenomenology (the science that looks into extending Standard Model) we'd definitely benefit from more data (with most viable data sources, in my opinion, being not the colliders but the detectors of extraterrestrial particles such as PandaX or Fermi-LAT). However, this doesn't stop us from getting new results, narrowing the window of possibilities for the properties of the Standard Model extensions. This "sorting a haystack in search of a needle" approach may not sound too cool, but this is exactly how we discovered the Higgs boson, for which we looked for more than twenty years. 2. In hep-th we currently lack either enough data (which we can't really collect now), or an ideological breakthrough in solving one of the hard problems. Unfortunately, the problems are indeed very hard, so that one of them (Yang-Mills existence) is a Millenium Prize problem. This caused the de-facto shift of hep-th into applied math, so now hep-th is not constrained by the data problem, and is developing as actively as an area of applied math can.

Re: Approaching 50 Years of String Theory

#129

Post by ajkjk »

tim333 wrote: post #125
ajkjk wrote: post #100

Earlier quoted context omitted.

The string theory model is structured from the start to reproduce existing theories as a consequence, so the problem here is a lack of understanding on your part rather than a mistake in the theory. I do suspect that most people who are working on this stuff (or any stuff for that matter) don't think very hard about the basic phenomenological claims to the point where they can explain them well. In particular your mo…

I can definitely buy a lack of understanding on my part - my understanding of all this is quite fuzzy. But I'm not sure string theories reproduce existing theories so much a say this is compatible with the other stuff in a handwavy way? I don't think there's any "we assume strings and thus can deduce quantum mechanics and general relativity" stuff? I don't think anyone can deduce quantum mechanics and Einstein's dedu…

It's not "we assume strings and deduce QM" it's "strings are a model which is defined so as to produce QM and also...". It is, by design, a theory of QM and GR. That's the point. It's a claim about what lies "below" the level of the individual fields in QFT which gives rise to them (and also gravity).

Re: Approaching 50 Years of String Theory

#130

Post by UncleMeat »

tejohnso wrote: post #124
20k wrote: post #45

Earlier quoted context omitted.

The problem with sabine is that she's become the worst person to make a correct point for the wrong reasons If you do research it becomes pretty apparent that a high number papers are not great. There's varying issues, but a big one is that the funding model incentivises pumping out papers which are often of low quality, researching whatever happens to be in vogue at the moment Literally everyone I've ever talked to…

Your paragraphs two, three and four are exactly what Sabine is communicating. So much so that it almost sounds like you pulled a transcript from one of her videos. I don't think you're describing "the" problem with Sabine. She's not what you want her to be but that's a you problem. You're describing your particular problem with Sabine. I appreciate that she's doing a lot to bring attention to the real issue despite y…

> I checked to see if she has come out in support of Jeffrey Epstein or something crazy like that, but no.

Bro she blurbed "The War on Science," a book stuffed with racists and sex pests complaining that they lost their jobs for falling in love with their graduate students, writing them love poetry on tumblr, and then kicking them out of their research group because they could stand to be near them. Or for saying that they "don't shy away from the word superior" when discussing white people being better at running societies and lying about the GPAs of black students. Or for taking joking photographs with human remains.

And yes, the authors of the book include people who provided support in the legal defense of jeffrey epstein.

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