meta user
network profile
| bio | website | |
|---|---|---|
| location | ||
| age | ||
| visits | member for | 1 year, 8 months |
| seen | May 18 at 22:15 | |
| stats | profile views | 21 |
|
May 13 |
answered | Can flux be proportional to $r^2$ in divergence theorem? |
|
Apr 4 |
answered | General solution for the Eikonal equation $| \nabla u|^2=1$ |
|
Apr 4 |
answered | Solving PDE using Hopf-Lax formula |
|
Mar 28 |
answered | When is this solution unique? - Method of Characteristics |
|
Mar 22 |
answered | Characteristic definition for higher order PDE |
|
Mar 20 |
comment |
Cannot understand method of characteristics Methods or at least suggestions: 1) keep in mind that this problem is a toy model for the "parting of the Red Sea": $u$ is the velocity, ("toy" because the acceleration $\frac{d}{dt}u(x(t),t)$ is zero so no force), the water to the left never moves, and to the right starts with $u=1$, what happens between must be traceable back to the origin using a characteristic; 2) read about it in a great book by Peter Lax, Hyperbolic Systems of Conservation Laws and the Mathematical Theory of Shock Waves. |
|
Mar 20 |
comment |
Cannot understand method of characteristics The 0 and 1 come from your initial values, $u(x,0)$. Draw $x$ horizontal, $t$ vertical, so that the evolution goes upward. |
|
Mar 20 |
answered | Cannot understand method of characteristics |
|
Jan 23 |
comment |
methods of characteristics for transport equation You might have assumed that $-(w_x,a(x)w)$ is negative? It doesn't have to be negative. |
|
Jan 21 |
answered | methods of characteristics for transport equation |
|
Oct 21 |
comment |
Good/better way to solve $y'' + 2y'/x + y^5 = 0$? The accepted answer does not appear to be correct. |
|
Oct 21 |
revised |
Finding the integral surface passing through a given curve added 2 characters in body |
|
Oct 20 |
answered | Finding the integral surface passing through a given curve |
|
Sep 20 |
answered | Good Physical Demonstrations of Abstract Mathematics |
|
Sep 20 |
comment |
Contractibility of the sphere and Stiefel manifolds of a separable Hilbert space see math.ucr.edu/home/baez/week151.html for the sphere. I suppose the Stieffel's are bundles with contractible fiber over a contractible base which would make them contractible, but I'm not sure in infinite dimensions. |
|
Sep 6 |
awarded | Yearling |
|
Jul 6 |
answered | Solving a system of quadratic vector equations |
|
Jul 2 |
answered | Poincaré Lemma Contractible Hypothesis |
|
Jun 11 |
answered | Claims in Pinchover's textbook's proof of existence and uniqueness theorem for first order PDEs |
|
Jun 10 |
revised |
Proof of An Integral Problem added 2 characters in body |
