Recent content by collectedsoul

What a great thread! I've added a lot of the recommendations to my to-watch list. I'll make a couple myself, both European sci-fi films. The first is Icarus XB-1, an old Czech film based on a book by Stanislaw Lem. The second is the newer Cargo, Switzerland's first and only sci-fi film. Special...

Ok...so do I break the equation down into 2 parts? A steady state one where d2u/dx2 + d2u/dy2 = 0 and another where it's = a*v and then add the 2 solutions? Or do I just do the latter equation?

So X''/X=m (a cpnstant) and Y''/Y = n (another constant) and m + n = a?

Maybe I'm being dense but I'm not able to separate the variables, I get X''/X + Y''/Y = a. So how do I get separate equations for x and y?

I'm not clear what you mean by eigenvalues for which u=0 is not the only solution. Could you please elaborate?

Alright...got it. There's another related PDE: d2u/dx2 + d2u/dy2 = a*u with u = 0 on all edges for some eigenvalues a. I'm not sure how to go about this. I can start by solving the steady state equation but what do I do about the condition?

Why just the normal component? If its insulated won't the tangential component also vanish? So δu/δx=δu/δy=0 at x=0,a and y=0,b. The question actually says that there is no need to solve the pde to get to u(x,y,t) - that there is a way to guess the answer without solving it. I can't think of...

Homework Statement A rectangular chip of dimensions a by b is insulated on all sides and at t=o temperature u=0. The chip produces heat at a constant rate h. Find an expression for u(x,y,t) Homework Equations δu/δt = h + D(δ2u/δx2 + δ2u/δy2) x∈(0,a), y∈(0,b) The Attempt at a Solution I'm...

Alrite. Two things were mentioned. First, that quantum gravity is a tiny sub-field of theory. Second, that few people outside those working on it care about it. If by the first was meant that its a tiny field because few people (comparatively) work on it, then I am agreed. I interpreted it...

This is the most ridiculous thing I've read on this forum. If this is from a physicist then its truly sad.

You might be pleased to know that I've decided to not do what I thought of and take up a Masters option instead. I figured I didn't want awkwardness after 2 years into the PhD.

Could someone advise me on starting a PhD program and leaving after 2 years with a Masters? Do people do this and what are the problems associated with such a course of action? For example is getting recommendation letters a problem and so on... The reason I need to know about this is that it...

When I wrote about 'where things are in the body' I meant in terms of whether they lie in cells, and if so what part of the cell, etc. I want to learn about the chemical compositions also. I've realized that maybe what I need is an introductory textbook to the subject. But really basic, nothing...

I started reading 'Genome' by Matt Ridley thinking it would answer my questions of what genes, DNA, etc are, but I found myself frustrated with its approach. He only gives a short outline of where chromosomes and genes reside (in nuclei of cells) in the preface but there's no clear explanation...

In an adiabatic process PVγ=constant Now I thought the work done by an ideal gas in an adiabatic process was given by the equation here: http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/adiab.html But while doing a GRE question the answer was given as PfVf - PiVi / 1 - γ Is this...