Is the photon entropy independent of its frequency? does it remain constant? I am trying to work out the photon gas entropy using such a postulate. Is this well justified?...

In the context of the solution of Schrodinger equation, is there any modified form of the WKB approximation which can be applied for the Schrodinger equation in cylindrical...

Also available as http://math.ucr.edu/home/baez/week256.html August 27, 2007 This Week's Finds in Mathematical Physics (Week 256) John Baez My European wanderings continue....

SHORT SUMMARY FOR BUSY READERS: whole-body translation and rotation - classical; torsions - classical; covalent stretching and bending - non-classical, assume ground...

25-AUG-2007 Hi all - Assuming, for the sake of simplicity, a non-rotating BH, it's been conjectured that for an external observer the "image" of any matter falling through...

In a weightless environment, a machine tool slide can be designed to move a distance equal to its own length, facilitating machine tool self-reproduction (MTSR). However,...

This is a plea for the experts to refine my understand: As I understand it, the current state-of-the-art on reconstruction of QM from postulates, in the vein of von Neumann,...

Can anyone point me to a proof of the identity stated in footnote 19 of Wheeler's Geometrodynamics, page 239. This identity is a follows: A_ua B^va -*A_ua...

I'd like to learn about the nature of time, about its ontological reality (if, indeed, time has any reality at all.) Ideally, I'd like to read a book or article by a...

When using the PPN in solar system tests or in cosmological expansion analysis, are off-diagonal elements important? Does anyone know what categories of analysis use...

In the current micro-thought, I present relativistic Lagrangians and discuss several limitations of the field-theoretic approach. This is motivated by the generalized belief...

Insofar as I understand, the action S = $d^4x L, where L is the Lagrangian density, is always a multiple of 1/2 unit of the reduced Planck's constant ($ denotes an...

The title says it all, really. I had initially interpreted the antisymmetry in the connection coefficients to imply that the metric is /not/ symmetric. However, I realized...

As is often the case, I've realised something obvious, but don't know where to head next -- so naturally I'm asking on sci.physics.research... Essentially, I'm wondering...

I hope this question isn't too elementary for this group. I (more or less) understand why the sky is blue (Rayleigh scattering because incoming sunlight turns air molecules...

Can anyone point me to some background for what looks like a bit of sleight-of-hand in Feynman's half of the 1968 Dirac Lectures (published together with Weinberg's lecture,...

OK, Basically, I am interested in studying quantum phenomena, specifically in a method that mimics the development of the field through history. I want to know where I can...

I've been reading about spectroscopy (specifically Ramsey spectroscopy) and they always have detuning so that the laser frequency is different from the atomic frequency. Why...

Also available as http://math.ucr.edu/home/baez/week255.html August 11, 2007 This Week's Finds in Mathematical Physics (Week 255) John Baez I've been roaming around Europe...

I am fascinated with the old Marcus-Sagnotti "Group Theory from Quarks at the Ends of Strings" (SPIRES http://www.slac.stanford.edu/spires/find/hep/www?j=PHLTA,B188,58 )....