Recent content by Pet Scan

How can I expect a direction when I don't even know if it is possible for Virtual photons to have circularly polarized modes? In other words; are the fundamental vacuum EM virtual modes circular polarized (like real photons) ? IOWs, in vacuum does QED take into account a virtual photon's...

I'm talking of the virtual EM modes of vacuum...

Is the reflection of a (massive) quantum particle from a mirrored surface considered a Lorentz Boost?? If it is non-collinear ?

Just to clarify...I didn't say a gravitational gradient. How about an electric potential gradient?

I am not that great at vector calculus , etc. Can someone show me how to take the time rate of change of a potential gradient? (Not homework) Thx.

Betcha a silver quarter I can see the difference. The lunar angular diameter can vary from 29.43 arc minutes at apogee to 33.5 arc minutes at perigee—over 4 minutes of arc -- or an increase of around 14% in apparent diameter or 30% in apparent area . Of course, that is according to...

Ok; just found this chart; looks like for 2016 the difference from closest to fartherest perigee is about -13,000 Km. (est. from the chart) However, this month's perigee looks like it barely beat out that of last April. Hmm. So if this was the closest in 70 years ...it must have been by a v...

I took a look at it last night . Real beautiful and bright. I could see it was apparently larger than usual full moons; but then again I have been a lunar observing guy for many years. Thanks Andy for the angular comparison ; I was wondering about that ...and also how much closer in miles is...

Thanks for the explanation Dr.Claude...

Does a circularly polarized laser beam, (say, 1 watt or so at visible wavelengths), impart linear or rotational momentum to air molecules.?? I'm not talking of ionization of air...which I know it doesn't, ...but rather momentum, in particular due to its Left or right CIRCULAR polarization...

Thx, SB; however, I am still stuck. How can I be sure I am obtaining a Left circularly polarized laser?? Will the manufacturer know...? How can I be sure >

I'm getting ready to do some testing, and need to decide which lasers to use . I need both left and right circularly polarized laser light . I was told that green diode lasers, the kind readily commercially available (usually around 200 - 500 mW.) , are LEFT CPL. 1. Is that usually true, and...

@parshyaa (and Sophiecentaur) and whoever else...Maybe I can clarify a bit...Hopefully. It seems that the confusion is arising because there seems to be some confusion about which mass, (central mass or orbiting mass) you guys are referring to when commenting (it needs to be clarified) AND...

Thank you TurtleM for the derivation... The usual (standard) Kepler eqn. that I was trying to reconstruct by squaring your equation is; T^2 / R^3 = 4(pi)^2 / G(M+m) ... but apparently the factor 1/32 kept appearing.. I think this clears it up here:(from your article)... "Note that T (orbit) in...

That is a unique rendering of Kepler's Law for free fall I've not seen. However, if I'm not mistaken Kepler eqn. for period of circular orbital motion should be equivalent to the oscillation period of m through a frictionless hole in the center of large Mass, M, if it has uniform mass density...