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Retired experimental particle physicist.

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


45m
revised Virtual particles and physical laws
edit after comments
1h
comment Virtual particles and physical laws
@FredericBrünner Baryons are not resonances and I am talking of baryons for the second diagram. My statement is that it is mathematical consistency that induces the concept of virtual particle, not only the trend of the Feynman diagram lines. Mathematical consistency gives the image analogue a "reality" , a correspondence to free particle attributes. In my opinion it is important to stress this, the quantum number continuity, when answering about what virtual particles mean, and it is missing in your second paragraph. ( which prompted me to add an answer)
1h
comment Virtual particles and physical laws
@FredericBrünner their correspondence to physical reality comes from all the other quantum numbers they are carrying which identify the particles physically, except mass. "virtual meaning"= virtual interpretation/identification.
10h
comment Virtual particles and physical laws
@FredericBrünner well perturbative calculations are all what supports the concept of virtual particles after all, it is a tautology what you say about the Casimir effect. Quarks cannot be free in our lab experiments, so a diagram without closure by other quarks can only have a virtual meaning : the mass of the quarks and the mass of the gluon in the diagram above are undefined and dependent on further intergrations which we gloss over with the jet language from the experimental observations.
11h
answered Virtual particles and physical laws
1d
revised Does proton make neutron charged by the process of induction/friction/conduction?
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1d
revised Does proton make neutron charged by the process of induction/friction/conduction?
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1d
answered Rigorous mathematical formalism of particle physics
1d
comment How does ultrasonic horn produce a convection current in the water?
I have made an answer out of my comments.
1d
answered How does ultrasonic horn produce a convection current in the water?
Apr
17
answered Send a signal from Earth to a planet billion light years away instantly
Apr
17
comment Why do grapes in a microwave oven produce plasma?
since this came up again I watched the video(s). Is it possible that alcohol is formed by the radiation of the microwave? The "plasma" looks to me a lot like burning alcohol fumes ( I use alcohol to start the fire in my woodstove at my vacation cottage)
Apr
17
comment Can a submerged capsized vessel be turned into a sort of diving bell and propelled forward like a submarine?
note that it could be done with a tin boat/large container as the buoyancy could be controlled by the thickness of the metal.
Apr
16
comment Does the energy-time uncertainty principle require energy levels to have finite width?
Of course most atoms are stable if not disturbed, i.e. they will not spontaneously decay and that would make very very thin lines.
Apr
16
comment Protons (as opposed to neutrons) to mediate nuclear fission?
Correct. The observation about charge in the question is also correct, that a proton has to overcome the coulomb force, but of course one wants the chain reaction to be self sustained in order to have a reactor.
Apr
16
answered How do we know we've unified two interactions?
Apr
15
revised How does the frequency of a particle manifest itself?
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Apr
15
answered How does the frequency of a particle manifest itself?
Apr
15
answered Reason for the experiment
Apr
15
comment About light waves
read the last sentence of your link. In any case the luminiferous is dispoved by MM "Luminiferous"="carrier of light" :nothing carries light