Hello. Can you write down this current operator you speak of?
What exactly do you mean by 'the point of the top of the edge mode band'?
I suppose in general I am confused about a few things: since you talk about k it seems you are doing periodic boundary conditions, but since you mention edge...
Sure! There is a nice basic review article by some of the people who first came up with the idea of topological insulators. I read it back when I was in undergrad and when I had a similar background as you, and I remember liking it back then...
Hello,
I am working in 1D here. For the ferromagnetic Ising model ##H = -\sum_k X_k X_{k+1}## (or ##H = -YY##) we know that the ground state is gapped and has a twofold degeneracy due to SSB (spontaneous symmetry breaking) of the spin flip symmetry ##P = Z_1 Z_2 Z_3 \cdots##.
I am now...
Aha, I have realized the answer. The key point is that [X,Y] \cong [X,Y \times \mathbb Z] since in these contexts we are looking at *base point preserving* maps, which are insensitive to the number of disconnected components.
Hello!
Trying to learn some basics of (topological) K-theory and came up with the following question:
From what I can gather, we can define (complex, topological) K-theory as K^n(X) = [X, B^n Gr^\infty(m)] with m going to infinity (indeed for m large enough, the answer is independent of it)...
In fact, I might be completely wrong about that last equation of motion. I suppose that would resolve my confusion. Can anyone confirm/disconfirm my last equation of motion? Thanks!
Hello,
So in the familiar case of non-relativistic particle Lagrangians/actions, we know the equations of motions are given by \frac{\partial \mathcal L}{\partial x^i} = \frac{\mathrm d }{\mathrm dt} \left( \frac{\partial \mathcal L}{\partial \dot x^i} \right)
In the familiar case of...
Vanadium as i said he wasnt a professor at those schools. In fact he has only partly been in the USA, in a subject unrelated to physics. Anyway I thought multiple opinions might make clearer exactly how I should estimate the effect. After all perhaps that professor maybe thought I could be very...
I'm a European student currently applying to a few grad schools in America. This year I am taking a gap year to travel through Asia (where I am now). A professor I recently happened to speak to (unrelated to the schools I applied to!) said two weeks ago that it should consider flying to the USA...
I am waiting to hear back from a few american universities about my application for a phd in theoretical physics. I just got news that I have obtained external funding from my home (European) country, enough to cover the first year (tuition + stipend).
I hope this will positively influence my...
Don't ignore Europe! Italy has the ICTP (International Centre for Theoretical Physics), which has a very good name. And this really intense 12 months master's looks very appealing IMO:
http://diploma.ictp.it/
Also take a look at eigenstate thermalization hypothesis (ETH). It's a tricky assumption quite crucial in quantum statistical mechanics, the analogue of the classical idea that the microcanonical and canonical ensemble are the same, which means--more physically speaking--that isolated systems or...