Discussions - sci.physics.research

	Time arrow and causality
	Dear all, A colleague of mine guesses that the time arrow is caused by the asymmetry of causality (cause and effect are not interchangeable), while the relationship to the invariance against time reversal of equations is not so tight. What do you think? Thank you and best wishes, Peter By Peter - 5:49pm - 1 new of 1 message

	Spasers for Solar Energy Intensification?
	I have often wondered if nano technology might allow for the development of a material that would soak up solar energy without focusing mirrors for some period of time . . . all day for instance. The material would be "pumped up" so to speak. It could then be "spas'd"(surface plasmon amplification by stimulated emission'd) to... more » By EdV - 2:50am - 4 new of 4 messages

	This Week's Finds in Mathematical Physics (Week 283)
	Also available at [link] November 10, 2009 This Week's Finds in Mathematical Physics (Week 283) John Baez We had a great AMS meeting this weekend at UCR, with far too many interesting talks going on simultaneously. For example, there were two sessions on math related to knot theory, one on operator algebras,... more » By John Baez - 2:40am - 1 new of 1 message

	What would be the field element for Path Integation of the Einstein - Hilbert Action!
	If one were to use the Einstein-Hilbert action in the usual expression for a path integral, where the metric tensor g_uv (or at least its gravitational field components h_uv) is itself the field of interest, in order to see what quantum gravitational looks like, the path integral would be specified by (k=the usual kappa):... more » By Jay R. Yablon - Nov 10 - 1 new of 1 message

	Generalized Calculation of Path Integrals for Quadratic Form Actions: Some Questions
	In an exercise linked at: [link] I have sought to examine the mathematics used to obtain a closed form expression for the path integral for a Lagrangian which is a general polynomial in the field psi, for any and all orders in the field, but... more » By Jay R. Yablon - Nov 9 - 1 new of 1 message

	TQC 2010: The 5th Conference on Theory of Quantum Computation, Communication, and Cryptography
	The 5th Conference on Theory of Quantum Computation, Communication, and Cryptography ---- TQC 2010 ---- University of Leeds, UK 13 - 15 April 2010 [link] ============================== ============================== ===========... more » By simone severini - Nov 9 - 1 new of 1 message

	lab equipment to repeat classic QM experiments?
	Hi! I would like to hear from an experimental physicist who could help recommend a list of the minimum equipment needed to repeat some of the "classic" QM experiments, for example the dual-slit experiment with single-photon reception, or an interferometer setup (demonstrating interaction-free measurements).... more » By BW - Nov 2 - 3 new of 3 messages

Finitary Path Integrals, Causality & Curved Space-Time

...In reply to Yablon's question -- the generalization of the Fourier Theorem was, in fact, the very impetus behind the recent work in generalizing the perturbation theory and renormalization formalisms to curved spacetime. It was largely heralded by Brunetti and Fredenhagen and works off of what I believe is called microlocal analysis.... more »

By Rock Brentwood - Oct 31 - 3 new of 3 messages

	Is magnetic flux quantified only in superconductors?
	While considering superconductors, it is generally accepted that there are created fluxons - some natural number of quantas of magnetic flux. I wanted to ask if the situation isn't more general - is magnetic flux quantified also in vacuum? It is suggested by Aharonov-Bohm effect as in superconductors - that... more » By Jarek Duda - Oct 31 - 3 new of 3 messages

	Looking for Feedback on an Exercise Calculating the QED Path Integral and Greens Fucntions in Curved Spacetime with Boundary Terms
	In the file linked below, I have laid out an exercise upon which I would appreciate your feedback: [link] Basically, I am attempting in the three respective sections of this exercise to: 1) Integrate-by-parts, the classical electrodynamic action, in curved... more » By Jay R. Yablon - Oct 30 - 6 new of 6 messages