Where are you in your string theory journey?
Have you mastered mirror symmetry and topological string theory yet?
Have you learned whatever the fuck the web based formalism is (arxiv.org
Thoughts on implications of AGT?
Should all young string theorists read Lurie's tomes?
Do you think string phenomenology will still be a meme 30 years from now?
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>Where are you in your string theory journey?
I've read BBS for the physics side of things. More interested in the Mathematical stuff though. Working on that now.
>Have you mastered mirror symmetry and topological string theory yet?
The usual A/B-Model stuff and MS defined via those models. Working on learning HMS, mainly the algebraic side right now.
>Have you learned whatever the fuck the web based formalism is
nope
>Thoughts on implications of AGT?
don't know anything about it
>Should all young string theorists read Lurie's tomes?
That shit is above my level. His Spectral Algebraic Geometry book has a surprisingly smooth introduction (i.e. A good chapter 0 introducing all relevant terminology to someone not familiar with infinity-category stuff) , but it is way too long and currently disconnected from string theory to justify reading.
>Do you think string phenomenology will still be a meme 30 years from now?
no
What math/physics topics should I learn before start grasping string theory?
1.Yeah that's probably the only situation I would recommend BBS is to get a quick rundown on the physics.
2. True, have you read Aspinwall's review? And nice, it'd be interesting to see what a non-pertubative understanding of topological ST on CYs looks like
3. understandable
4.It's the Alday-Gaiotto-Tachikawa Correspondence and in a nutshell it's correspondence between a 4d N=2 and a Toda conformal block and its understanding is requiring an increasing "categorification" of QFT not too different in spirit from what HMS did.
5. How big is the relation between his Higher Topos Theory and his proof of the cobordism hypothesis, if you know?
6. Yeah N=1 d=4 seems to be the next frontier of non perturbative understanding in the next decade
you definitely need to have intro quantum field theory down pretty well and 2d conformal field theory wouldn't hurt cause the CFT section in the intro string textbooks are too local to string theory in my opinion (although ch.15 of Polchinski is okay) and don't give a good taste of the subject as a whole, which once understanding, make the application to string theory more intuitive. Other than the necessary stuff about de Rham cohomology and the jist of singular homology, you just learn the math as you follow the textbooks and your interests.
still waiting for the string to turn into a garotte
>True, have you read Aspinwall's review?
If you mean the "Dirichlet Branes and Mirror Symmetry" book, then yes that is what I am reading for an introduction to HMS (also the SYZ part looks interesting).
> How big is the relation between his Higher Topos Theory and his proof of the cobordism hypothesis, if you know?
I know essentially nothing about Higher Category theory. I have only ever worked with 1 and 2 categories (context of Hartshorne level Alg. Geom. plus some def. theory and moduli stuff). I know HMS involves Ainifinity categories which is the last chapter of the book mentioned above.
Mmm no I was referring to his 2003 TASI notes which is basically that book in a 130 page review form and only mentions A-infinity algebras (doesn't seem hard to think about its corresponding infinity category) briefly. But I'll definitely have to check that book out? Btw are you undergrad or grad? Math or physics?
*didnt mean to put that first question mark
Undergrad Math&Physics. I finished the math degree requirements in 2 years so I just audit various graduate math courses a semester while completing the physics portion.
Interesting, that's basically how my math and physics degrees worked out too. I'm applying to grad schools in the fall and on a gap year.
Why the fuck have so many people fallen for this fraud? Shit made literally zero verifable predictions over three decades of existence.
Completely independent of physical relevance, it has helped orient mathematics in some very interesting directions.
>reads Woit once
Think of string theorists today as just a type of mathematical physicist that studying objects that were inspired by string perturbation theory (the only part of string theory that can be well defined as a closed set of ideas) which was discovered long ago that it can describe quantum gravity in some special cases. "String theory" today is really just a blanket term for all of the non perturbative knowledge that we know from this program to describe not just the special cases but quantum gravity in general (which often don't even involve strings to begin with). Moreover, the fundations of quantum field theory (and hence quantum mechanics because after all it is just QFT in one dimension) are still poorly understood and it is widely beleived by experts that this knowledge lies in this blanket term of topics called string theory.
Will string theory find the missing equations to solve the three body problem?
That is more an issue for people in PDEs.
Basically this
Theories of physics are usually looking for the differential equations themselves rather than say something about their analytic solutions.
physics theory is a bit of a joke at the moment. The truth is is that we have no idea where to go in BSM because there are no clues from the LHC. I am more excited to hear about the deviations from SM at LHCb which are happening with respect to lepton universality and CKM gamma angle. Perhaps that will give you more to go on.
Yeah if you give a physicist a differential equation they will likely just apply various approximations until it is something an undergrad could solve. Or they will just plug it into Mathematica or something.
I still say people are sleeping on qft in curved space time...
It doesn't work for any significant degree of curvature.
that depends on what you are trying to do... Moreover, there are a lot of experiments coming online that will study its properties too...
I mean if you read some of the posts here you'll see that string theory is really a blanket term for a lot of things some of which is related to qft on manifolds that aren't boring enough to be diffeomorphic to flat Minkowski space. For example, in the OP I mentioned the AGT correspondence which was inferred when considering a 6d QFT where two of the dimensions can take the shape of a donut with n-holes. Also, mirror symmetry (a weaker form of which people can prove rigorously) very roughly is the notion that quantum gravity can be physically equivalent on two different manifolds with different metrics, curvature tensors and all that. Although, qft without quantum gravity on a curved spacetime alone cannot be fundamental for a host of technical reasons, but was obviously useful for the derivation Hawking radiation.
>a bit of a joke
A bit cynical but yeah it's nothing will be like the 70s for long time. And the deviations you mention aren't significant yet and I would imagine any pheno model explaining these would look rather cumbersome with new gauge bosons and higgs that have a new "family" charge and awkward couplings (just a guess I'm not in pheno). This would be exciting if true but not likely in my opinion. "String theory" today though is trying to understand the foundations of qft by studying toy models with usually a lot of supersymmetry for simplicity and these approaches usually require knowledge of common string theory (without quotes) lore. Essentially the hope is that it would teach us more with what we already know (the dream would be to understand QCD non perturbatively) and learn a lot of new math along the way.
ads/cft is the only thing worth investigating the rest is masturbation
there's a string theory in the AdS so wouldn't it also be worth it to study that theory in other situations as well? I might be replying to b8 but I've literally never heard this opinion before. Also, BFSS matrix theory is basically a 1d theory dual to an 11d theory (instead of a difference of one dimension in the AdS/CFT case) and AGT describes a space of 4d theories dual to one 2d theory so yeah that's like old professors now who still call category theory a meme but still use say fundamental groupoids in their research.
I don't see how providing deep insights into geometry is masturbation. The Mirror Symmetry of the topological A&B-Models implies the Homological Mirror Symmetry conjecture should be true. HMS implies a deep relation between two traditionally separate fields of geometry, yet there is absolutely no reason it should be true other than String Theory.
Bump
Isn't there some stuff with a Ads/QCD correspondence thing.
Eh that's the name of a research program that is fairly heuristic and full of guesses. To summarize, the first AdS/CFT correspondence showed was between a string theory whose massless interactions resembled a supergravity on a 5d AdS (with an internal 5-sphere) which could describe the strong coupling behavior of a QCD theory with 16 supersymmetry generators (N=4). Because QCD with no supersymmetry is present in our worlds and no one knows how to calculate its strong coupling behavior, the program you mentioned tries to extract predictions from the highly supersymmetric case that don't depend too much on the supersymmetry. The Wikipedia page on it describes basically the extent of the success so far which is not much. Some guys were able to calculate a value of a viscosity in a real world strong QCD process by doing a gravitational calculation but these results are more inspired than physically well motivated. As you lower the supersymmetry of the QCD (from N=4 to 2 to 1) and add quarks the dual string theory that describes gravity becomes more complicated and more difficult to extract its states. Real world (N=0) strong QCD is known to have string-like excitation but they are very messy and it posses many states and interaction among the hadrons that can't be seen from a stringy picture. My guess is that a string theory dual to real world QCD would hardly ever stringy at all and more knowledge would be gained from considering the underlying M theory of the situation, whatever that may mean. These complications I think would only very weakly preserve the novelty of "dude calculating hadron scattering using black holes lmao" that is cleanly present in the N=4 case.
Second to last bump
stop sexualizing my professors pls
I think you're misunderstanding what based means but if you must know I remember seeing Gukov at that tiny cafe by the Caltech bookstore with a woman (gf or wife idk) that was hot af.
Was she japanese? I know her name but I've never met her.
This was two years ago and I don't think so but I could be wrong. I just remember she was slender and between 5'7-5'10 and just saying to myself that Gukov did well for himself.
"...[M-Theory] is a very hard theory to follow, and at the same time I've done it a bit more extremely than I've ever done in the past. It's topologically designed to be that way, and you can't undo that, but we can diminish the effects of it.......It's a little disjointed, it's bold in terms of jerking people around....I may have gone too far in a few places"
Gotcha. They recently had a kid so I'd say he's doing very will indeed haha
Lmao nice. Have you taken a class with him?
yeah and it was fuckin lit.
Btw here is a fun part of a talk he gave recently,
youtube.com
why are models in physics so boring?
Thanks! I haven't watched any talks on his recent work on RG flows/resurgence but his papers on them are probably my favorite works of his in recent years. And I assume it was BBS level string theory right? And have you taken any classes with Marcolli? I suspect that would be pretty lit as well.
what do you mean by models? like the standard model?
lal
29:00
Marcolli classes are sorcery. I go to lecture and everything she says makes perfect sense, but when I try looking at my notes later my brain just short circuits.
Adeles are real fucked up man.
>>what do you mean by models? like the standard model?
any model about any system
you're boring