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2h
comment Understanding the basic concepts of quantum mechanics using a model
@RobotMan I am not into a computational lingo, i am a simple experimental physicist. The simple fact about the cards being in a fixed state can be ascertained by a kibitzer, i.e. a third party to the game who does not disclose knowledge.
4h
comment Could there have been two “Big Bangs”?
Welcome to the site. When you have acquired some reputation you will be able to comment on the question. This is a personal opinion, comment, not an answer to the question which needs justification with physics statements .
4h
comment Understanding the basic concepts of quantum mechanics using a model
@RobotMan classical mechanics , statististical, thermodymics, classical electromagnetism and all models derived from them have as an "axiom" that underlying levels are deterministic to derive their very successful models for measuring and predicting situations, including probability distributions. The validation is in the success of the models macroscopically. Indeterminacy found experimentally forced the introduction of quantum mechanics. . There are still physicists trying to eliminate indeterminacy in QM by underlying deterministic theories (cf 't Hooft)
13h
comment How can a probability distribution have wavelength (de Broglie wavelength)?
"probability peaks at a particular place" you are thinking of classical statistical probability for random motions. Probability is a more general term. en.wikipedia.org/wiki/Probability
14h
comment Understanding the basic concepts of quantum mechanics using a model
@RobotMan you are going into metaphysics. classical physics knows that the card is either black or red.
15h
comment Тhere is at least some proof that vacuum is able to propagate light?
" to know what is experiment that shows light is travel through a vacuum?" You have never heard of the Michelson Morley experiment that debunked the luminiferous ether? en.wikipedia.org/wiki/Michelson%E2%80%93Morley_experiment
15h
comment Neutrinos and DNA
You are remembering wrongly. It is the muon cosmic flux that has been proposed sometime, as there are lots of muons going through us, and they are charged, therefore do radiative damage. see physics.stackexchange.com/questions/28450/… . a review arxiv.org/ftp/arxiv/papers/1211/1211.3962.pdf
20h
comment Can electrons within a positive ion absorb and reflect light?
The electrons in the band are bound too, though there are many since the band energies are practically continuous. The energy value is the work function of the metal in the photoelectric effect. i.e. the electrons in the band are not free, they are in a collective state but with a binding energy that keeps them in the lattice. The photoelectric effect measures that work function en.wikipedia.org/wiki/Work_function see table hyperphysics.phy-astr.gsu.edu/hbase/tables/photoelec.html. The scattering will be inelastic, not reflection .
1d
comment Can electrons within a positive ion absorb and reflect light?
yes, the conduction band needs a lot more energy in insulators as you can see in the link I gave, that is why they are insulators in the band framework
1d
comment Is the center of mass in general relativity equal to the center of mass in newtonian gravity?
Note that the other answer is stating that "But in general relativity there are generally no conservation of momentum" . Assuming momentum conservation answers the question for a sub phase space .
1d
comment Can electrons within a positive ion absorb and reflect light?
Yes, a single metal atom when neutral has the last electrons in a shallow energy level. When in a lattice the quantum mechanical solutions allow the outer electrons to be shared and become free to "move" in the lattice. The lower levels are bound to the individual atoms. The band electron orbitals encompass many molecules.
1d
comment How can a product of Bra and Ket be a scalar if they are matrices?
"(which, I think, means a complex number)." No, a scalar in is a real number in physics, en.wikipedia.org/wiki/Scalar_%28physics%29 it is a "length" of the projection of one vector on another, in the space under consideration. Think of invariant masses in special relativity. the mass of the electron is the "length" of its four vector .
1d
comment Quantum field theory's interpretation of double slit experiment
@garyp paticle in the quantum mechanical regime has a different definition, it is a quantum mechanical entity. After all the standard model has a table of point particles with masses and spins that enter into the lagrangian for the calculations. Operator fields are very useful, but having sat through a nuclear physics course (back in 1962) with creation and annihilation operators for nuclear states, I always see them as an ingenious mathematical tool.
1d
comment Тhere is at least some proof that vacuum is able to propagate light?
Have a look at the answer here physics.stackexchange.com/questions/109982/… . Physics theories are validated by experiments and falsified if a prediction is wrong. The transmission of light in vacuum is continually validated, not only light from the stars but also in experiments of high energy physics, like the ones at LHC.
1d
comment Quantum field theory's interpretation of double slit experiment
@CuriousOne All physics theories use mathematics to fit experimental observations. The mathematics are not the physics, is all I am saying. The observations are. To assign reality, in the sense of : "fields exist even if there is nothing there", to what is a mathematical frame is a matter of metaphysics.
1d
comment Quantum field theory's interpretation of double slit experiment
@We will not agree on this. QFT is useful for calculations and it is only calculations giving checkable numbers that are relevant to physics. All the rest is mathematics. I am just pointing out the continuity between first (relativistic) and second quantization. There is no discrepancy.
1d
comment Quantum field theory's interpretation of double slit experiment
"One doesn't have to carry a nonsensical picture of a tiny blob of "something" being two places at once." only if one confuses the probability of being at either slit with real existence . Even in the creation and annihilation frame, it is the probabilities that are generated . quantum mechanics is about probabilities.
2d
comment What constitutes an answer to a physics question on this forum?
As a comment of mine is used as an illustration, I want to stress that comments are comments and answers are answers, on this site. A comment expresses opinion and is not an answer which must be based on peer reviewed physics *( preferably with links) or standard textbook physics. .
2d
comment Compton effect in photo-electric?
@aquirdturtle we are talking at cross purposes. The compton effect, I have given a link in my answer, is about scattering of a photon off an electron, and might be extended to scattering of a photon off a field , where the generator of the field takes up the momentum balance. The spectrum is continuous. The photoelectric effect gives a lower bound to the rebounding momentum of the electron, and this implies bound states with a specific ionization energy , I also gave a link in the answer. If the electrons on the metal surface were not quantum mechanically bound, there would be no cut off.
2d
comment Compton effect in photo-electric?
@aquirdturtle my comment addresses the photoeletric effect, which is not compton scattering. Of course photons can scatter off the field of atoms, that is not what the question is about, imo