
The Dangerous Irrelevance of String Theory - seycombi
https://www.math.columbia.edu/~woit/wordpress/?p=9375
======
noobermin
I hate to do it but I have to do it, the "String" phenomenon is an out-growth
of the academic (industrial?) complex. When you have a group of closely knit
scientists from a handful of universities who have a steady stream of cheap
labor and fed by a media that bedazzles their untestable hypotheses, when
you're propped up by that hype and prestige, the fumes that academics at the
top feed off, then you can plunge further into the deep, while offsetting the
externalities and opportunity costs onto governments and broken graduate
students who eventually find themselves unemployable after about 5 to 6 years.

I smelled the stink early on when a project at the LHC I was joining found 6
(plus or minus 4!) possible supersymmetry events in the two years of PBs of
LHC data(!) in their specific search. I made the bet against supersymmetry and
went for a less hyped field, and now that their funding is drying up, I'm
happily taking almost double (or more) the salary compared to other graduate
students since I'm in another field. Haven't regretted since.

The hype behind string theory and HEP in general needs to die. There are so
many interesting problems worthy of investigation that are not High Energy or
Quantum Gravity. Yes, few things beat the fun math of HEP and string theory
(although there are close contenders in the condensed matter world), few
things--except perhaps validation in experiment...you know, the entire point
of science in the first place.

~~~
orbifold
String theory had lots of success just not as a phenomenological theory.
Monstorous moonshine, which was proven by Borcherds using techniques developed
for String Theory, Witten's Contributions to Chern Simons and Donaldson
Theory, and Perelman's proof of the Poincaré conjecture come to mind.

~~~
auntienomen
Perelman's proof of Poincare was quite independent of string theory. No need
to get greedy.

~~~
orbifold
The Lagrangian that he used is the effective field theory of a bosonic string,
in his first paper he explicitly referred to that fact.

~~~
auntienomen
Yes, I'm aware of that. I still don't count this as a string theory success.
Borcherds proof of the Moonshine conjecture uses the no-ghost theorem in a way
which is completely unsurprising to anyone familiar with QFT. Perelman's proof
of Geometrization, in contrast, uses the string-frame Lagrangian in a manner
which is by no means implicit in the string theory literature. The deep
content of those papers comes after he's decided which functional to work
with.

------
snarfy
The case for string theory

[https://www.youtube.com/watch?v=Q8ccXzM3x8A](https://www.youtube.com/watch?v=Q8ccXzM3x8A)

tl;dr - Nobody theorized strings. They were trying to solve the scattering
problem of w-bosons and came up with a solution. The interpretation of the
solution is strings.

~~~
euyyn
Thanks for the link; TIL.

He answers "But is it falsifiable?" with "Of course it is! If special
relativity is false, so is string theory." Which misses the point completely.
Is it actually falsifiable?

~~~
woodandsteel
You know there is something wrong with an idea when someone feels compelled to
argue for it by giving a word a different meaning than it usually has, but not
explaining he is doing that.

~~~
posterboy
falsifiable literally has fals~ in it.

------
vorg
> The significance of these negative results is not that they disconfirm a
> strong prediction of string theory, but that they pull the plug on the last
> remaining hope for connecting standard string theory unification scenarios
> to anything observable.

The reason String Theory first became so popular in the mid-1980's was because
of its prediction of a massless chargeless spin-2 particle (the graviton)
which behaves like gravity in a quantum setting. Surely this could be called a
proven observation of String Theory?

~~~
Chronos
As I understand it (not being a physicist): the graviton, _if it exists at
all_ , would have to be a massless chargeless spin-2 boson for it to fit our
understanding of what particles are. But the graviton has never been observed,
nor has any quantized behavior of gravity or its General Relativistic effects,
so it doesn't count as an observation by String Theory; there are other models
that also give rise to gravity-as-we've-observed-it, up to and including just
gluing the Standard Model to General Relativity and calling it a day.

~~~
zodiac
I don't know much about this, but I've read that the standard model and GR are
mutually inconsistent? How do you "glue them together"?

~~~
freeflight
>standard model and GR are mutually inconsistent?

I'm not an expert, but from what I understand GR and standard model don't
exactly contradict each other, they are both considered "valid" and self-
consistent on their own as they merely describe different processes on
different scales?

On their own, they work just fine but if we try to stick the two of them
together, to get a "unifying theory", we get different outcomes than we
expected, that's why we are now trying to find the "glue" that fits the two of
them together while still making sense in the end.

At least that's my layman's take on this whole situation.

------
PhantomGremlin
It's very sad how so many bright physicists have made this their life's work,
and yet:

 _the problem with string theory is that, in its landscape version, it has a
hugely complicated and poorly understood high energy scale behavior, seemingly
capable of producing a very wide range of possible observable effects, none of
which have been seen_

~~~
Animats
Like "expert systems". (Anyone remember those?)

I went through Stanford CS in the mid-1980s, just as it was becoming clear
that expert systems didn't do very much. But there were many faculty heavily
invested in the technology. Feigenbaum was running around telling Congress
that the US would "become an agrarian nation" unless they funded a big
national knowledge system lab headed by him. Strong AI was supposed to work
Real Soon Now. What actually happened was the "AI Winter" \- for about two
decades, not much happened. The AI startups from the 1980s went bust.

~~~
fusiongyro
Some of that technology is actually used today. Systems like JBoss Drools, IBM
Operational Decision Manager. Government agencies sometimes use modern
versions of these things to ensure that policies are followed. Eligibility for
medicaid, for instance, is often decided by rules systems that are descended
from systems like CLIPS. This technology isn't super-sexy compared to deep
learning but there are application areas where it is still relevant.

------
dataphyte
Why doesn't pure math get similarly attacked? Clearly math has generated lots
of economic and scientific value, but it seems to me that there isn't much
difference between string theory and, say, math work on the Monster Moonshine
group or whatever.

~~~
liberte82
Because pure math doesn't make a claim to be anything other than it is. String
theory supposedly describes real things in the real universe, and as such it's
a valid criticism to say it can't be tested.

Maybe it's a marketing problem. If string theory would move outside of the
realm of physics and into that of mathematics I don't think it would have
these issues.

~~~
dataphyte
That's my thinking as well: just re-brand string theory as math. It's not as
though string theory will be testable anytime soon, so the criteria of
verification is just hurting the field.

------
woodandsteel
One reason why theories need to be testable is for checking out which of two
theories is correct. If both theories fit with what has been observed so far,
you think of a situation where they make different predictions, and then
collect some new data and then see which theory turns out to be correct.

String theorists seem to think their theory is so beautiful that there is no
need for it to be able to pass this sort of test.

~~~
dragonwriter
> String theorists seem to think their theory is so beautiful that there is no
> need for it to be able to pass this sort of test.

I don't see any evidence that string theorists don't believe that having
practically-testable predictions is desirable.

IIRC, actually, there was quite a bit of noise a few years back when string
theory was the basis for in-principle-testable predictions regarding quantum
entanglement, but I don't know if any practical tests have been constructed.

~~~
woodandsteel
The blog post in question is about how at least some string theorists think
that string theory has been proven true, in spite of the fact that no one
knows how to test it empirically. The post includes a link to an article that
argues against this

[https://www.nature.com/news/scientific-method-defend-the-
int...](https://www.nature.com/news/scientific-method-defend-the-integrity-of-
physics-1.16535)

So yes, they would like it if there were practical tests, but no, they don't
think they are necessary.

------
woodandsteel
If I understand the post correctly, it is not just that ST has not been
verified, but that the way the theory has developed over time has made it
harder to verify.

------
paulpauper
_I think the comparison to EM or GR is pretty much absurd. For one thing it’s
comparing two completely different things: tests of a particular prediction of
a theory (EM or GR) that made lots of other testable, confirmed predictions to
the case of string theory, where there are no predictions at all. More
relevant to the argument over how long to wait for an idea to pay off is that
the real question is not the absolute value of the amount of progress, but the
derivative: as you study the idea more carefully, do you get closer to
testable progress or farther away? I don’t think anybody can serious claim
that, 33 years on, we’re closer to a successful string theory unification
proposal than we were at the start, back in 1985. I’d argue that the situation
is the complete opposite: we have been steadily moving away from such success
(and thus entered the realm of failure)._

The problems string theory are attempting to answer are many magnitudes more
complicated than general relativity and electromagnetism and hence require
tests many magnitudes more precise and complicated. It's possible such tests
may never be developed and that there may be many competing theories of
everything with no way to ever ascertain which one is correct.

New theories take not just decades, but centuries to develop. There was at
least a three-hundred year gap between the development of Newtonian gravity
and general relativity. Much of string theory is only a couple decades old. If
physicists and mathematicians decide that string theory is untenable, they
will gradually abandon it, similar to how in capitalism products become
obsoleted in favor of newer, better ones. There is no need for someone to
determine which theories are worth pursuing or or not; the ‘marketplace’ of
ideas does that automatically, gradually nudging the natural progression of
research towards better ideas as old ones are discarded or modified. For
example, 120 years ago aether theories were conjectured the propagation of
light and gravitation, but these theories were later were supplanted by
special relativity.

[http://greyenlightenment.com/falsifiability-string-theory-
an...](http://greyenlightenment.com/falsifiability-string-theory-and-policy/)
String Theory succeeds because it offers a means that is logically consistent
to bridge gravity and quantum mechanics, and the strings themselves are
building blocks for all particles. If someone can come up with a logically
consistent theory that is as encompassing as string theory and can be tested
and verified with existing technology, the physics community is all ears.

The tyranny of verificationism impedes scientific progress. Let string
theorists do their thing/string.

~~~
_FKS_
"The tyranny of verificationism impedes scientific progress. Let string
theorists do their thing/string."

This is a very dangerous path. Science without empiricism is religion.

[https://arxiv.org/pdf/1609.01966.pdf](https://arxiv.org/pdf/1609.01966.pdf)

~~~
woodandsteel
Exactly. Without empiricism, people are free to dream up anything they wish,
and there is no way to settle disagreements.

------
Sniffnoy
This is just a link to Peter Woit's blog. I'm assuming you meant to link to
the most recent entry (as per the title):
[https://www.math.columbia.edu/~woit/wordpress/?p=9375](https://www.math.columbia.edu/~woit/wordpress/?p=9375)

(Could we get a mod to fix this? Thank you!)

~~~
dang
Sure. Changed from
[https://www.math.columbia.edu/~woit/wordpress/](https://www.math.columbia.edu/~woit/wordpress/).

