Recent content by Mosis

this thought was inspired by the recent news about FTL neutrinos. of course i suspect their instruments are broken and that no such thing happened, but regardless, the question stands: it's easy to talk about the rest frame of classical objects where the notion of "trajectory" applies and...

I am confused about the usual derivation of the ideal magnetohydrodynamic equations, as given for example here: http://theoretical-physics.net/dev/src/fluid-dynamics/mhd.html The problem is that there are a few different "currents" to consider. For example, in the momentum equation, the...

hello! i would like to be able to understand and appreciate the proof of the poincare conjecture. i have some idea of where to begin, and my supervisor is going to help me out (i'm starting a master's in pure math and my supervisor does geometric analysis), but i was wondering if anyone here...

why do you think this should be true?

I got a 69 in physics 1, and last summer I won a scholarship that granted me a paid internship at the Perimeter Institute for Theoretical Physics + paid for my 4th year tuition costs. don't worry about it ;)

Electromagnetic Theory II Differential Geometry Measure Theory and Fourier Analysis Statistical Mechanics Interpretation and Foundations of Quantum Mechanics I'm a 4th year mathematical physics major at the University of Waterloo btw.

Nonsense. I have a "friend" who has a memory better than anyone else I know and yet also smokes more than anyone else I know ;)

The sooner you lose this attitude, the better. I recommend losing it right now. No matter who you are, your "talent" alone will not be sufficient. What you really need to develop is the habit of working hard. I recommend enrolling in a course in which you can barely succeed having worked your...

Homework Statement Let f_n:[a,b] -> R be a pointwise bounded, continuous family. Prove there exists an interval (c,d) < [a,b] on which f_n is uniformly bounded. Homework Equations no equations The Attempt at a Solution I'm stuck. If we have equicontinuity, then this is easy, so I'm...

also, I'm not sure why you suggest plotting the solution to that equation - how can that help me?

why are you assuming Y is positive? also, exp(-r) is convex but decays as r goes to infinity. Of course, it blows up in the other direction, but in my case, Y = Y(r), and r > 0, so I'd really need some information about the first derivative to conclude all nontrivial solutions are unbounded.

I was thinking about that kind of perturbation scheme, but the fact that we have Y^1/3 makes that intractable i.e. what to do with \left(Y_0 + CY_1\right)^{1/3}?

wow, 46 views, no reply - is this really that uncommon?

This has come up in my research, and my supervisor and I don't really know how to proceed. It reads r^2\frac{d^2Y}{dr^2} + r\frac{dY}{dr} - \left(\frac{3}{2}\right)^2Y = Cr^3Y^{1/3} I know the RHS is an equidimensional DE which has the nice solution Y = r^{\pm 3/2}, but I have no idea...

Homework Statement Prove that if every continuous real-valued function on a set X attains a maximum value, then X must be compact.Homework Equations None really.The Attempt at a Solution None really, not sure where to start. I know that if a space is compact, every function attains it's minimum...