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0 votes
0 answers
71 views

Mathematical theory of plasma

I am working on a heavily mathematically project about plasma. In particular, I want to find references that treat the problem from microscopic models that include relativistic and magnetic effects (...
The N's user avatar
  • 113
0 votes
0 answers
24 views

How to know if a set of equations are Lorentz Invariant Spinors

I'm currently busy with a course in QFT and am completely baffled by Spinors. In particular there are two parts, that while I mostly understand the theory, struggle to show mathematically (especially ...
WizardLizard's user avatar
0 votes
1 answer
597 views

Dimensionless form of the ODE for a simple pendulum with forcing and damping

I'm tasked with analysing the behaviour of a simple pendulum with driving and damping, which has the equation of motion: $$mL^{2}\ddot{\theta} + k\dot{\theta} + mgL\sin{\theta} = FL\cos{\Omega}t$$ For ...
vesbe1998's user avatar
0 votes
0 answers
146 views

How can I find the fixed points of this Duffing oscillator differential equation?

The problem is to find the fixed points for the equation: $$\ddot{x}+ \dot{x}- x + ax^3=b \cos(ct)$$ where $a,b$ and $c$ are constants. The Duffing oscillator is a 2nd order differential equation and ...
Light Hikari's user avatar
2 votes
0 answers
51 views

Very hard quasilinear PDE

I have the following PDE in two dimensions $$ 2\partial_x\partial_y\sqrt{1-u^2}+\left(\partial^2_x-\partial^2_y \right)u=0, $$ with $u=u(x,y)$ on some domain of the plane. Now, numerically I can ...
DanielKatzner's user avatar
0 votes
0 answers
21 views

Interpretation about the exchange of energy among oscillators

I'm studying Hamiltonian system and in particular the role of frequencies in these systems. What I want to understand is about the physic interpretation of some definition. Considerer a Hamiltonian ...
Giovanni Febbraro's user avatar
1 vote
2 answers
2k views

Partial differential equations that involve an infinite "continuum" of variables: "Each point in space contributes additional degrees of freedom"?

Page 11, Nonlinear Dynamics and Chaos, by Strogatz, says the following: This is the domain of classical applied mathematics and mathematical physics where the linear partial differential equations ...
The Pointer's user avatar
  • 4,322
3 votes
1 answer
84 views

How to find out the critical angle of a ball separating the circle?

Question: Let function $x:\mathbf R_+\to[0,2\pi]$ satisfying the second-order nonlinear ODE \begin{equation} \left\{ \begin{aligned} \ddot x(t) &= \sin x(t)-\cos x(t)+{\dot x(t)}^2, \quad t>0;...
Dreamer's user avatar
  • 1,972