2,073 reputation
38
bio website
location
age
visits member for 1 year, 5 months
seen 7 hours ago
stats profile views 251

Jul
24
answered What does symplecticity imply?
Jul
22
awarded  Citizen Patrol
Jul
22
answered Units of Distance, Pressure, and Temperature
Jul
21
comment Hamiltonian mechanics and special relativity?
+1: thanks a lot for that link; my own musing went into the direction of modeling relativistic mechanics via local contact structures on the space of geodesics parametrized by arc length (ie proper time); that's just another way to arrive at $J^1_1Q$, and now that I know where I need to end up eventually, I might revisit that idea...
Jul
20
comment QM without complex numbers
@kηives: the space of states for a finite-dimensional quantum system is the complex projective space $P_n\mathbb{C}\cong\mathbb{C}^{n+1}\setminus\{0\}/\mathbb{C}^*\cong U(n+1)/U(n)\times U(1)\cong S^{2n+1}/S^1$
Jul
20
answered QM without complex numbers
Jul
19
comment Introduction to differential forms in thermodynamics
@Ron: I don't believe that article is paywalled (I just accessed the PDF from home and via a free proxy); in section 8, it is shown that the equations of state of the ideal gas fix a lagragian submanifold of a symplectic space as an example of the interpretation of the legendre transformation in context of symplectic geometry
Jul
19
comment What's the meaning of the general solution and the particular solution in differential equations?
@Ron: I slightly reworded the last part
Jul
19
revised What's the meaning of the general solution and the particular solution in differential equations?
added 30 characters in body
Jul
19
comment Introduction to differential forms in thermodynamics
@Ron: re Legendre transformation, I was thinking along the lines of section 8 of numdam.org/item?id=AIHPA_1977__27_1_101_0
Jul
19
comment What's the meaning of the general solution and the particular solution in differential equations?
@Ron: added a small note about the non-linear case
Jul
19
revised What's the meaning of the general solution and the particular solution in differential equations?
add note about non-linear equations
Jul
18
revised Hamilton-Jacobi Equation
fix integration variables, add time as parameter to trajectories
Jul
18
comment Introduction to differential forms in thermodynamics
@Arnold: I'll send you my list once I've done some further reading...
Jul
18
comment Introduction to differential forms in thermodynamics
@Arnold: I started to read your book today (just the first chapter for now) and kept a list of typos/missing symbols, statements I find questionable etc; are you interested in that (ie should I keep adding to my list or stop now before investing any real work)?
Jul
18
comment Introduction to differential forms in thermodynamics
@Arnold: your comment contains the quote "Infinitesimals and differential forms are the same thing, something well-known to mathematicians"; that seems to have been a typo, tough, if your argument is actually that differential forms and not infinitesimals are the correct framework for thermodynamics (which might indeed be the case - I don't know enough about non-standard analysis to be a judge of that)
Jul
18
comment Introduction to differential forms in thermodynamics
@Ron: it doesn't? how do you interpret the legendre-transformation in terms of infinitesimals?
Jul
18
comment Introduction to differential forms in thermodynamics
@Arnold: infinitesimals and differential forms are not the same thing; the framework of non-standard analysis got a rigorous set-theoretic formulation in the 70s and there are results which are indeed more easily formulated using infinitesimals; I'm not sure if non-standard analysis adds anything to thermodynamics in particular, though
Jul
18
revised Hamilton-Jacobi Equation
added 6 characters in body
Jul
18
answered What's the meaning of the general solution and the particular solution in differential equations?