Experimental nuclear and particle physicist. These days I'm teaching, but I've spent a lot of time on nucleon structure in fixed target electron scattering and neutrino oscillations using reactors and beam sources.

21h
comment Has confinement been experimentally observed?
@innisfree The fact of substructure at least was well established in the 1950s when the proton form factors (polarized and unpolarized) were measured. The knowledge of the hadron spectrum had to have come from somewhere before Gell-Mann and Zweig could work on the date.
21h
comment Kirchoff's loop law
Do you think I object to your answer? I don't and in fact voted for it, but I thought there was room for another approach to the problem.
21h
comment Kirchoff's loop law
If there is an externally imposed, changing magnetic field then (a) you can't formally define a "potential" anymore and (b) If you're going to fake it (which you can and generally should) you have to include a EMF from the induction or KLL doesn't work. See WetSavanna... answer on the linked question.
22h
answered Kirchoff's loop law
22h
comment Has confinement been experimentally observed?
@innisfree If you insist on the language of QCD, then you can't have it until you have that same language, but the observation that (a) nucleons have substructure and (b) you can't seem to knock the pieces loose is what prompted the need to deduce the sub-component properties from the hadron spectrum. Those facts are the observation of confinement.
23h
comment Do electrons get accelerated or decelerated by the atoms of the anode during X-rays production?
There is no unique definition of acceleration vis a vis deceleration. The observer's frame of reference can change one into the other.
1d
comment Has confinement been experimentally observed?
Like every other observed fact at the most fundamental level it is simply the way the universe appears to work. Some observations in science can be explained in terms of more basic observations (and learning to do that is one of the pillars of the discipline), but at some level everything is built on a foundation of observation.
1d
comment Has confinement been experimentally observed?
Er ... it was a phenomenological observation before it was part of any theory.
1d
answered Short story where advanced civilization doesn't understand their technology
1d
comment Does "normal torque" exist?
The floor exerts friction on the ruler spinning in contact with it and friction always points in the direction opposed to relative motion. The results is a perfectly ordinary torque.
2d
comment Condition for formation of interference pattern
No time to write an answer now. This is a way of arguing about the spacial coherence of the light.
Nov
25
awarded Notable Question
Nov
25
comment Does ethanol activate any taste or smell receptors?
Er ... part of your quote reads "It does have a effect, which results from the alcohol interacting with the cells in the mouth"
Nov
25
comment What academic functions does a Professor Emeritus usually serve?
Some of my best graduate courses were taught by emeritus professors: folks who were only teaching the subject they most loved and could devote otherwise unreasonable amounts of time and attention to the project. That serves their passion and my development.
Nov
25
comment Difference between official and unofficial transcripts
You can also generally have official copies delivered directly to the recipient without going through your own hands.
Nov
25
comment What does the Atomic Form Factor means?
"they have fallen out of fashion as a research tool" Hmmm ... well, they've remained important in the transition energy regime (a few GeV scale) exactly because it is hard to do accurate calculation above the nucleon mass but below the perturbative QCD scale. Also in applications like weak-axial scattering where a small signal must be extracted from a large vector background from electromagnetism.
Nov
24
comment How to rebut denials of the existence of photons?
This is really the core of (at least one of) Lamb's point. He doesn't argue against QED, but rather that the word in consistently abused in ways that are not consistent with a modern understanding of quantum optics.
Nov
24
comment What are the hypothetic cases when entropy of a closed system may decrease?
Describe a system in which there is no way to have a change from a micro-state of maximum entropy to another such state. Then anytime the system is in a micro-state of maximum entropy, any change causes a momentary decrease. I believe that a 1-D Ising model is such a system.
Nov
24
comment How to rebut denials of the existence of photons?
@KyleKanos The flip side is---of course---www-3.unipv.it/fis/tamq/Anti-photon.pdf (the paper that user31748 references) and arxiv.org/abs/1204.4616
Nov
24
comment Do time dilation tests prove that it exists or that atomic clocks are faulty?
"Time is what clocks measure" is a tautology. Time is an expression of the fact that two events that happen in the same place can none-the-less be separate from one another. The separation is the time (duration) between them. A device which allows you to compare intervals in that separation is a clock. The phrase can be taken as a definition of a clock as easily as of time, but it is true. To suggest that there is some underlying more correct time you must show that there is a way to measure it.
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