There is a wonderful hypothesis concerning how many stars may you count in your night sky, if you are far away from any meaningful strong gravitational system. This...

If an observer was constantly accelerating at say 7.3 x 10^ -8 cm/sec squared, then, using a pre-relativistic formula v=gt, he would achieve c/2 in ~ 6.8x 10^9 years, and c...

It is sometimes supposed that the cosmological principle determines that Maxwell's equations hold in empty space, and hence that cosmological redshift must be calculated...

In article , "Spud" wrote: BellT wrote: I feel the same way! I have posted in a...

New Scientist is a British-based publication where many thousands of lay people get their information on scientific matters, and (IMHO) it does an excellent job about 70%...

In QED and QCD, is it correct to hold the view that the upshot of renormalization after all the loop diagrams are calculated, cutoffs chosen, etc., is that the interaction...

In article , "Chalky" wrote: If an observer was constantly accelerating at say 7.3 x...

Dear Friends: This is a follow up to the discussion in some earlier threads, and in particular, to the suggestions made by Igor Khavkine that I: 1) "Instead of wondering...

On Mon, 25 Sep 2006 23:22:01 +0000 (UTC), Oh No wrote: Thus spake George Dishman "Oh No"...

The position of Pioneer was calculated from Doppler information. Ranging was not available. Can anyone explain why ranging could not be used? Is this just a limit on...

Dear friends, The anomalous magnetic moments of the charged leptons are presently understood in terms of perturbative corrections Lambda^u of the form gamma^u -- Gamma ^u...

Bootstrap model is a phrase I haven't heard in many years. The idea seems to have fallen out of currency, though it was much talked about in the 60's and 70's as the basis of...

What Electric and Magnetic field have an oscillating charge?? For example Q=q0.sin(2.pi.f.t) Or Q = q0.Heavside(t) (Heavside(t)=1 if t0, 0 if t0) or Q =...

Hi, I have 2 different light rays which have different wavelengths (for instance one is red and the other is green). I'm sending these rays to 2 photodiodes. Is the...

It has been put to me that instead of giving an overview of Relational Quantum Gravity as I did in a recent post, I would be better to give the actual calculation which...

Given some lagrangian, when we integrate out degress of freedom either in quantum or classical field theory, we usually obtain an effective one. Are there cases where, upon...

I've made a small web page describing some thought experiments in the vicinity of a Rindler...

http://www.physorg.com/news12054.html " Scientists funded by the European Space Agency have measured the gravitational equivalent of a magnetic field for the first time in...

This is a hypothetical question. Imagine there are two objects in space above the Earth. They are say 3 light seconds apart from each other and an approximately equal...

I am reading a book and a review paper about supergravity. However, without any explanations, they introduce rarita-schwinger action. Could somebody explain to me how this...