Skip to main content

All Questions

0 votes
0 answers
36 views

When is the derivative of Hamilton flow respect to initial conditions independent of time?

Consider a Hamiltonian system with coordinates $\Gamma^A=(q^i,p_i)$ and let $X^A(s,\Gamma_0)$ be the Hamiltonian flow (i.e. a solution to Hamilton's equations) parametrized by time $s$ and initial ...
P. C. Spaniel's user avatar
0 votes
1 answer
92 views

Why inverse flow of separable Hamiltonian with even kinetic energy can be written like this?

Why is it true that the inverse of the flow of a separable Hamiltonian with even kinetic energy can be written as $\phi_N \circ \varphi_t \circ \phi_N$ where $\varphi_t$ is the flow of the Hamiltonian ...
Euler_Salter's user avatar
0 votes
1 answer
207 views

Definition of time-reversibility of flow of Hamilton's equations

I cannot find a good, simple definition of time-reversibility of the flow $\phi_t$ of Hamilton's equations $$ \dot{z} = J^{-1}\nabla_z H(z) \quad \text{where} \quad z = (q, p)^\top \quad \text{and} \...
Euler_Salter's user avatar
1 vote
1 answer
56 views

Is an integrator with unit Jacobian determinant sympletic?

Consider a numerical integrator $\phi(q, p)$ having $|\text{det } \phi'| = 1$. Can we say the integrator is sympletic, that is that $$ \phi'^\top J^{-1} \phi' = J^{-1} $$ where $$ J^{-1} = \begin{...
Euler_Salter's user avatar
2 votes
2 answers
725 views

Quantum particle moving on the surface of cylinder

I have a problem with a spinless particle moving on the lateral surface of a cylinder of radius $r$. If no Hamiltonian is given, is $H=\frac{p^2}{2m}$ only? What are the Hamiltonian's eigenfunctions ...
Salmon's user avatar
  • 941
2 votes
1 answer
327 views

Rewriting the Laplacian on a curved manifold

I guess there is a sense in which the following is true: "The Laplacian written on a Riemannian manifold $(M,g)$ can be seen as adding a coordinate dependent mass field to the Laplacian on ...
gradstudent's user avatar
5 votes
1 answer
269 views

The WKB approximation and the Cotangent bundle

When we say (see pag. 9 of Lectures on the Geometry of Quantization) that the image of the differential of the phase function lies in the level set of the classical Hamiltonian is it simply ...
Xlsx2020's user avatar
  • 139
0 votes
1 answer
55 views

Hamiltonian as differential manifold

I know that phase space $(q^i, p^i)$ can be treated as manifold. But for me defining hamiltonian as a function also leads to new manifold $(q^i, p^i, H(q^i,p^i))$. Like map from open set $(q^i, p^i) \...
Vicolls's user avatar
  • 21
1 vote
0 answers
1k views

Hamiltonian for particle moving in a sphere

Context: I know that if we have a particle (say, with unit mass) moving in the plane $\Bbb R^2$ subject to a spherically symmetric potential $V\colon \Bbb R^2 \to \Bbb R$, it will move along the ...
Ivo Terek's user avatar
  • 545
0 votes
0 answers
208 views

General geometric interpretation for the Hamiltonian and of the cases when it is not the total energy of the system

What is the geometric interpretation for the Hamiltonian? Also, is there geometric interpretation of when and why it is not equal to the total energy of the system? Lastly, what is the most general ...
TheQuantumMan's user avatar