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2
votes
1answer
23 views
Electric current streamlines in induction cooking vessel
I am looking for a plot of the typical streamlines of the electric induced currents ("eddy currents") in a induction cooking vessel.
How can one theoretically predict the streamlines? How is it ...
4
votes
2answers
74 views
Solve the angular part of Schrodinger equation numerically
I would like to solve the angular part (the one for what is usually called the $\theta$ angle) of a time-independent 3D Schrodinger equation
$$
\frac{\mathrm{d}}{\mathrm{d}x}\left[ (1-x^2) ...
0
votes
0answers
30 views
Irregular events within an otherwise cyclic time series
(I have asked the same question on math.stackexchange, but I figured that physicists might actually be more likely to have encountered the same problem before.)
I am considering a time series with a ...
0
votes
1answer
77 views
Superconducting gap, temperature
Tinkham (page 63) states that the temperature dependence of the gap energy of a superconductor $\Delta(T)$ can be calculated using the following integral: http://i45.tinypic.com/w1s13t.png
How can ...
1
vote
0answers
77 views
neutron transport approximations for nuclear rocket modelling
I'm pretty ignorant regarding neutron and nuclear transport modelling, but i'm interested in trying to pursue it for a particular pet project. It regards modelling of nuclear reactions like those ...
2
votes
2answers
124 views
numerical formulation of Dirac equation plus electromagnetic field
I have the following equations describing the electron field in a (classic) electromagnetic field:
$$ c\left(\alpha _i\right.{\cdot (P - q(A + A_b) + \beta mc) \psi = E \psi } $$
where $A_b$ is ...
3
votes
3answers
218 views
Can a wavefunction be solved to any arbitrary precision, given enough computer time?
I learned that the wavefunction for the hydrogen atom can be solved analytically (we did the derivation in class), but that for more complicated atoms it is "impossible" to solve and that only ...
-3
votes
3answers
117 views
How to recognize broken candies from whole ones [closed]
Let's say I have a bag full of sugar candy. Some will be whole, some will be dent, some will be broken (in part, or half, etc).
Let's say I have a device with an input box where I empty the bag, and ...
0
votes
0answers
74 views
Coupled decay behavior? [closed]
I solved the following "coupled" ODE numerically, whit forward Euler scheme:
$$
\frac{\text{d}N_a}{\text{d}t} = -\frac{N_a}{\tau_a}
$$
$$
\frac{\text{d}N_b}{\text{d}t} = ...
4
votes
0answers
328 views
Interpretation of Stiffness Matrix and Mass Matrix in Finite Element Method
I would like to have a general interpretation of the coefficients of the stiffness matrix that appears in FEM. For instance if we are solving a linear elasticity problem and we modelize the relation ...
0
votes
1answer
382 views
Calculating Kramers-Kronig using Mathematica
First of all, I know there is a Mathematica group in beta, but I don't think the problem of the following is directly a Mathematica issue.
I am trying to calculate the change of the refractive index ...
1
vote
1answer
166 views
Numerical algorithms to generate a random wavefunction from a thermal ensemble
I am seeking an algorithm to generate a random wavefunction = $\sum {c_i |\varphi _i\rangle }$ from a thermal ensemble, whose density matrix $\rho \sim e^{-\beta H}$, without the need to diagonalize ...
12
votes
2answers
49 views
Numerical Analysis of Elliptic PDEs
I am looking for an elementary reference regarding issues of stability in numerical analysis of non-linear elliptic PDEs, particularly using the finite difference method (but something more ...
1
vote
1answer
202 views
Transparent boundary condition. Beam propagation method
I am interested in the finite-difference beam propagation method and its applications. I try to solve the Helmholtz equation. At first, i would like to solve numerically it for the easiest case, ...
3
votes
1answer
209 views
Numeric method to calculate the charge distribution on a conducting surface?
If I have an arbitrary (closed?) conducting surface and a nearby charge density, is there a simple numeric way of computing the induced charge distribution on the surface?