trying to decide between phd in pure physics or phd neuroscience (AI related)

[sabinscabin]

I'm currently a graduate student doing theoretical physics at a tier 1 school. I'm trying to decide between these two.

1) stay in pure physics
PROS:
- since I've already taken field theory, I can start doing research quickly
- will probably learn some useful simulation skills (I'm considering doing lattice QCD)
- I enjoy (i.e. have a great deal of fun) learning physics very much. Taking more theoretical physics classes will allow me to build my analytical skills

CONS:
- I don't think high energy problems are particularly important for mankind, even though they are pretty interesting to think about. I'm not sure how enthusiastic I can remain for a field that I enjoy doing, but know is pretty unimportant in the grand scheme of things (for society, not the universe)
- will most likely have to switch fields after graduation (I don't mind not becoming a professor; I just have no idea what jobs, besides quant finance, are available to people with simulation skills and theoretical particle physics)

2) switch to neuroscience (AI related)
PROS:
- I think the problems I'll be working on (where does intelligence come from, how does the brain work) is probably one of the most important problems in terms of the big picture
- group I'm considering to join seems to be very well funded, students are happy, the PI is a very experienced, very well connected, famous, and works on a large variety of projects
- group has a proven track record of placing students at companies and faculty positions

CONS:
- will have to take a lot of bio + EE classes, possibly like an entire year of classes before actually doing research. This will probably lengthen my stay in grad school by a year or two
- Since it's a change in field, I have no idea what methods people in this field use to attack problems. I have no idea whether I will enjoy using these methods the way I enjoy doing physics
- I often feel intimidated by colleagues that come from backgrounds closer to this field, like (EE, CS, Neuro, etc)

Can anyone please give me some advice? Thanks.

[Acut]

Switching areas is probably one of the coolest things one can do.
One year of waiting before starting research is not a bad idea. Better wait one year than wasting your life doing something not fulfilling.

Since Physics develops good reasoning skills, don't be so worried about the new methods you would learn in neuroscience. Intimidation is normal if you are a beginner.

In short, worry less about catching up and more with choosing what you'd REALLY want to do.

[Acut]

By the way,
since you are from a different field than most of the other guys working with you, you will offer a unique point of view. I find it is an advantage to think differently from everyone else in the room.

[Mute]

There are areas of physics that use field theory that aren't high energy. Condensed matter makes a lot of use of field theoretic techniques, and could in principle have important implications for mankind (materials, new technologies etc.). So, you could also consider switches groups within physics. This is not to say not to switch to neuroscience, but that there are other switching options where many of your current skills will carry over and you might not have to take a lot of more coursework.

[Theorem.]

In short, worry less about catching up and more with choosing what you'd REALLY want to do.

I agree. After reading the original post, I don't find it 100% clear which topic you are actually more interested in.

[sabinscabin]

I agree. After reading the original post, I don't find it 100% clear which topic you are actually more interested in.

I see. Let me clarify. I find the methods used to solve problems in pure theoretical physics really cool and interesting, logically simple, and fun to do. However, the conclusions that they draw (scattering amplitudes of processes, critical exponents of field theories, etc.) I find utterly inconsequential.

On the other hand, I'm not sure I'm comfortable with the methods biologists and neuroscientists (even the theorists) use. It lacks a certain grittiness that theoretical physics has. In theoretical physics you start with as few assumptions as possible and then "crunch" the assumptions to arrive at the final result. However in biology I feel there's a great deal of handwaving going on, and oftentimes they spend more time just naming and categorizing all these different objects and what they do. It's hard for me to put it into words. However, I find the questions asked in neuroscience (how the brain works, how consciousness arises) very very profound, interesting, and extremely important.

[Theorem.]

I see. Let me clarify. I find the methods used to solve problems in pure theoretical physics really cool and interesting, logically simple, and fun to do. However, the conclusions that they draw (scattering amplitudes of processes, critical exponents of field theories, etc.) I find utterly inconsequential.

On the other hand, I'm not sure I'm comfortable with the methods biologists and neuroscientists (even the theorists) use. It lacks a certain grittiness that theoretical physics has. In theoretical physics you start with as few assumptions as possible and then "crunch" the assumptions to arrive at the final result. However in biology I feel there's a great deal of handwaving going on, and oftentimes they spend more time just naming and categorizing all these different objects and what they do. It's hard for me to put it into words. However, I find the questions asked in neuroscience (how the brain works, how consciousness arises) very very profound, interesting, and extremely important.
I can understand your problem regarding theoretical physics, although you have to understand that this is a consequence of the career. Theorists often work their whole lives trying to arrive at substantial solutions only getting bits and pieces on the way there. I can definitely see why you like the problem solving methods used. I should point out though that in biology and neuroscience the area of consciousness studied is very limited- as of now our interpretation is still mostly philosophical and psychological. Consciousness is often studied in neuropsychology.
I wish I could point you too a healthy medium-but I am not qualified nor aware of one. I am sure that you will favor one at least in the soon future.