Recent content by bjnartowt

Suppose I wanted to publish a physics paper. It costs nothing to publish to arxiv. Why (setting aside the obvious advantage offered by peer review and the mistakes it can catch) would I publish in a pay-journal if I have something that is free? Sorry if this is an ignorant question. I am trying...

Thank you all for your replies. My next question is, naturally, if plasmons can carry thermal energy.

It is well-known that the electron gas of volume V has an equation of state p=p(V) and thus has a bulk modulus $$B=-V(dp/dV)$$. Suppose the electron gas had no underlying lattice but was confined. Do phonons emit and absorb in such an electron gas at finite temperature? The reason I ask is...

I am wondering if there is a book with solved example problems I can follow so that I can carry out the following calculation: I have a set of unperturbed electron Green functions $g^{r0},g^{a0},g^{<0},g^{>0}$ and phonon Green functions $d^{r0},d^{a0},d^{<0},d^{>0}$ which are for a central...

Does the squaring operation indicate scalar/vector/etc. multiplication, or does it indicate the inner product under which you have orthonormality? After all, ## \sin n\pi x ## and ## \sin m\pi x ## for ## m\ne n ## are orthogonal (and also normal with the appropriate coefficient), and: ##...

As stevendaryl indicated, be careful to distinguish equation-indices with those indices that are summed over. In the following, I put a "prime" on indices that I sum over: ## 0 = \frac{{\partial {\cal L}}}{{\partial \phi }} - {\partial _\mu }\frac{{\partial {\cal L}}}{{\partial \left( {{\partial...

Homework Statement Suppose an amount of power P_{\ell} is delivered to a load by a black box with potential difference V_T across it, driving current I through a single loop. If an amount of power P_b is applied to the black box, to sustain I at V_T, then the efficiency of this black box acting...

I hope this is helpful.

You are asking what entropy S is produced by time t by diffusion through a medium characterized by diffusion coefficient D_{ij}? If so, could you indicate the arrangement of the system at t = 0; is a point-source diffusing?

Thanks, Choppy. I have no problem with reading, but it may be that I'm reading the wrong things. I try and read the latest developments in thermoelectricity, but constantly find myself having to go back and read/solve problems in my core-class-textbooks. Then, whenever I start the day intending...

I am wondering what the first steps are to finding an interesting calculation, and doing it. My adviser seems concerned only with me writing my thesis to hurry up and get me out of the program, rather than helping me develop my CV and involving me in other calculations he may be doing. It seems...

Anyway--I don't expect someone to troubleshoot my code. I just need the name of a book in which this is discussed and treated pedagogically.

I am sorry--I see at least one mistake. My analytic convolution was taken for boxcar functions that run to intervals as wide as -2 to 2, but the convolution I effect numerically is over the interval -1 to 1. On remedying this problem, one convolution-function still appears stretched out with...

I took two boxcar functions, f=bxc(x,-1,1); g=bxc(x,-2,2); (f has a value of 1 from -1 to 1, and g has value of 1 from -2 to 2; they are 0 everywhere else). The analytic form convolution can be computed, integrate(f(x')*g(x-x')), from x integrated over all domain, yields...

I know how to do it, and I have code that, in theory, should work properly. The code is behaviing in such a bizarre manner that I am almost certain I need to consult books about the "theory" of convolving-by-fft in order to grasp what the bug is.