/sci/ - Science & Math

>>10264508
>QFT + GR
Dead field. You have to understand that theoretical physics relies on experimental data to fit and create models. In fields where experimental data is literally impossible to obtain you'd have to compete with mathematicians for funding.
>more experimental side
Prepare to do more number crunching than a programmer.
>just QFT for QC and QI.
QC does not utilize QFT unless you're doing tensor networks, and that has the same convergence issue as QFT ON TOP of the decoherence issue of QC. Conventional QC typically takes more CS theory than physics to do research in, the amount of quantum it takes is just elementary QM.
Topological QC on the other hand is a relatively new field that might be worthwhile to go into. Again, it doesn't utilize QFT but it does apply some of the more mathematical techniques used and concepts in the theory of strongly-correlated matter to build quantum algorithms.
t. Mathematical physics PhD

>>10264590
Numbers Have An End is the only correct theory that can change this field.

>>10264615
youre not contributing anything useful, stop posting

>>10264508
>>10264590
Anything topological in qi/qc is ultimately based on topological qft. Sure the methods and such are pretty different from "standard" qft that hep uses, but it's still a bona fide qft. Same goes for stuff like cqed architecture.
Quantum chemistry simulation also uses models approximations from a qft approach. There are 1st quantization methods sure, but generally speaking, the 2nd quantized forms are more popular.

None of this is particularly "fundamental", mind you, unless you go into cmt where exotic topological phases are popular right now. But again, it's not the same brand of ”hep-th qft" that you might be partial towards.
Don't know anything about the current state of quantum gravity research but it doesn't seem too bright. Experimental gravitational astronomy seems like it'll be on the rise though, what with ligo being such a success and other countries following suit.

>>10264677
>is ultimately based on topological qft
Incorrect. There are topological codes that do NOT admit a field theoretic description, such as Haah's cube code or the [math]\mathbb{Z}_2[/math] lattice gauge theory. These models have fracton phases with a sub-extensive ground state degeneracy that blows up when you take the thermodynamic limit, which means that there is no coherent theory to describe them in the continuum.
These fracton codes can use the mobile intersections of submanifolds as qubits. It's one of the most interesting things in TQC at the moment.
>it's still a bona fide qft
Incorrect. Something that does not allow a continuum description in the first place cannot be a field theory, classical or otherwise.
>Quantum chemistry simulation
Which is a completely different field than TQC.
>2nd quantized forms
Again, that's only applicable when you have a coherent classical field theory in the first place, which quantum chem have but fracton phases do not. This is borderline irrelevant to what I was talking about.

>>10264508
the question you’re asking is pretty irrelevant. if you want to do either “QFT+GR” which would fall under “high energy theory” or computational GR, then step 1 is to apply to physics grad school. you have two years of classes before you need to be in a research group, and finding a good research group requires a good “fit”, and bear in mind few people are shoe-ins at their top choice grad school

if you care about quantum computing and quantum information, that’s a good field to get into, but it’s not like a common mainstream physics PhD topic. there may be a few but it’s sort of niche, and a lot of people working on research there are CS or cryptography math folks