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8 votes
1 answer
702 views

Can any symplectomorphism (1 Definition of canonical transformation) be represented by the flow of a vectorfield?

For this question I will use the definition that a canonical transformation is a map $T(q,p)$ from the phase space onto itself, which leaves the symplectic 2-form invariant (which is the definition of ...
Quantumwhisp's user avatar
  • 6,763
11 votes
2 answers
1k views

Does Hamilton Mechanics give a general phase-space conserving flux?

Hamiltonian dynamics fulfil the Liouville's theorem, which means that one can imagine the flux of a phase space volume under a Hamiltonian theory like the flux of an ideal fluid, which doesn't change ...
Peter's user avatar
  • 175
2 votes
2 answers
1k views

What are the mathematical models for force, acceleration and velocity?

In mechanics, the space can be described as a Riemann manifold. Forces, then, can be defined as vector fields of this manifold. Accelerations are linear functions of forces, so they are covector ...
elflyao's user avatar
  • 905
1 vote
2 answers
129 views

Time derivative of unit velocity vector?

Let's say I have some parametric curve describing the evolution of a particle $\mathbf{r}(t)$. The velocity is $\mathbf{v}(t) = d\mathbf{r}/dt$ of course. I am trying to understand what the expression ...
James Thiamin's user avatar
6 votes
3 answers
2k views

Paths in phase space can never intersect, but why can't they merge?

Page 272 of No-Nonsense Classical Mechanics sketches why paths in phase space can never intersect: Problem: It seems to me this reasoning only implies that paths can never "strictly" ...
George's user avatar
  • 337