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location Greece
age 75
visits member for 4 years, 5 months
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Retired experimental particle physicist.

The picture is a fayum . It looks like aunts and cousins of mine :).


Apr
25
comment What are you studying when you study a Harmonic Oscillator in QM?
It is not an academic exercise. Please note that any symmetric potential when expanded in a series has as first dominant term the x**2 term. Thus the harmonic oscillator is a good approximation for many physical situations given the right constants. Vibrations of classical strings are also harmonic oscillators, and are a basis for string theory for particles, after all.
Apr
25
comment How can a star emit light if it is in Plasma state?
@auxsvr I cannot see how one could separate radiation form accleration/deceleration in magnetic fields from acceleration/deceleration from electric fields at these distances.
Apr
25
comment How can a star emit light if it is in Plasma state?
@auxsvr It takes years for the light from the center of the sun to come out to the surface. Plasma carries magnetic fields with it.en.wikipedia.org/wiki/Sun has a good enough description
Apr
25
answered How can a star emit light if it is in Plasma state?
Apr
25
answered Need help visualising transverse waves
Apr
25
comment Need help visualising transverse waves
en.wikipedia.org/wiki/Transverse_wave has an animation
Apr
24
awarded  Revival
Apr
24
answered What is the energy distribution of light if it has an infinite length?
Apr
24
comment Could you theoretically map the internal distribution of mass in a black hole using Hawking radiation?
No. Nothing leaves the interior of a classical black hole, by construction. Hawking radiation is a "surface" effect deduced from a semiclassical argument and involves only the vacuum at the horizon.
Apr
23
comment Can we squeeze atoms?
Pistons have surfaces. Surfaces are made up out lattices of atoms. The kinetic energy will be dissipated on all the surface atoms and individual electrons will get a tiny amount of it, maybe enough to send them sideways but certainly not enough to display particle scattering properties. Do me a favor and forget this piston business.
Apr
23
comment Can we squeeze atoms?
an infinitessially small amount of the available energy will go to individual electrons in your "squeezing" . Electrons beween layers of matter are never free anyway.
Apr
23
revised Tokamaks and the reason they are still not efficient
corrected statement and added link
Apr
23
comment Tokamaks and the reason they are still not efficient
@garyp That is what I remember, which was an argument for going on to the large designe of ITER. Still maybe my memory is at fault: it says only 6-% to breakeven goal here efda.org/faq/…
Apr
23
comment Can we squeeze atoms?
@iamnotmaynard yes, I believe that with nanotechnology there is a chance for a "table top" accelerator.
Apr
23
comment Can we squeeze atoms?
electrons would ionize molecules, i.e. occupy energy levels above the ground state for the molecule. No, atomic distances cannot be squeezed by any stretch to the extent you are imagining. and again, there are 10^23 atoms per mole. a piston would disperse the energy to all those zillions of atoms on the surfaces.
Apr
23
answered Can we squeeze atoms?
Apr
23
comment Can we squeeze atoms?
NO. elementary particles cannot be squeezed because they cannot be contained in a vessel. Take photons, or electrons. They will be absorbed by the walls of the so called piston, which will have molecules after all. Pistons will deform or melt the lower plate anyway so even protons will not be sitting ducks for squeezing.
Apr
23
answered Tokamaks and the reason they are still not efficient
Apr
23
answered Why isn't perpetual motion possible, even though we are so technologically advanced?
Apr
23
answered W + jets at NLO