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Questions related from Sofia D. Wechsler
I wasn't able to get von Neumann's book "Mathematical Foundations of Quantum Mechanics". But I saw many descriptions on his scheme of measurement, all of them saying the same things. What I was...
12 December 2018 5,675 21 View
There are different proofs that the quantum nechanics (QM), more exactly the quantum formalism (that was NEVER contradicted by experiment), does not admit a substructure of particles following...
11 November 2018 3,696 97 View
Look at the following process: a photon wave-packet is split by a beam-splitter into the superposition ~ |a> + i|b>. In continuation, each one of the wave-packets |a> and |b>, passes through a...
08 August 2018 8,148 7 View
Consider a radio wave of wavelength λ=100m. If the electromagnetic waves are streams of photons, then a radio wave has to be a stream of photon. How big can be a photon of this wavelength? For a...
09 September 2017 5,270 4 View
Weak measurement are a relatively new trend in quantum experiment. They mean to determine the so-called Bohmian velocity, but in fact they measure the average linear momentum while disturbing very...
07 July 2017 5,484 15 View
In his lecture https://www.youtube.com/watch?v=EtyNMlXN-sw Sidney Coleman, a famous physicist in the quantum theory and famous lecturer in the domain, tried to explain at a simple level the...
05 May 2017 4,368 86 View
Assume two space-stations at rest with respect to one another. In one station works the experimenter Alice, and in the other, the experimenter Bob. Consider that at the time t0 by the clock of...
12 December 2016 6,431 18 View
Assume two identical fermions, e.g. 3He, and polarized with the same spin projection, e.g. z-polarized. The fermions are sent from afar to the same detector - see attached picture. The dimensions...
10 October 2016 4,371 15 View
Consider a frame of coordinates F, in movement with a velocity V with respect to the lab. Assume that we prepare in the lab a beam of spin 1 bosons, polarized along a direction Q which makes an...
10 October 2016 6,748 18 View
Dear friends, I was informed of an article in the journal "Le Monde" commenting new experiments done with the Large Hadron Collider. As I am not a specialist in the matter of the Standard Model,...
09 September 2016 7,761 10 View
The Stern-Gerlach (SG) apparatus splits a wave-packet according to the projection of the spin of the particle on the direction of the magnetic field. However, in some experiments, we need to...
07 July 2016 6,191 5 View
I saw the following opinion which picturize the human beings as programmed automats (I don't remember the author): A human being is built from anatomic systems, and reacts to the environment...
06 June 2016 9,771 19 View
It is known that John Bell used the assumption of locality in proving his famous inequality. But, I don't see a need for this assumption. Assuming that a distribution of probabilities exists P(A,...
06 June 2016 892 54 View
Imagine two fermion wave-packets of Gaussian form, whose paths cross one another, see figure. The blue circles represent the two wave-packets at different times. At a certain time the wave-packets...
05 May 2016 9,016 81 View
Atom optics is typically done in the last years with gratings of light. These gratings successfully implement mirrors and beam-splitters. Two counter-propagating laser beams cross one another, and...
03 March 2016 6,705 5 View
The Hanbury Brown and Twiss (HB&T) experiment was done properly with photons. The team of Aspect performed with fermions experiments that have some analogy with the HB&T experiment in the...
03 March 2016 637 5 View
What is the meaning of the uncertainty relation ΔE Δt ≥ ħ during the energy measurement of a particle? My understanding is that Δt should be the time-window of the detector. But I am not sure....
03 March 2016 1,577 4 View
I think that inside a reactor one can obtain neutrons of different energies. My question is if it is possible to create two sources as in the picture?
02 February 2016 4,664 1 View
Consider a gas of identical boson-particles, e.g. atoms of a noble element. Let the gas be at a low temperature, s.t. the mean kinetic energy of the atoms is low. I think that during their...
01 January 2016 2,159 6 View
In the B-E formula for the average number of identical bosons that can occupy a single particle state ψj , out of a set of such states ‹n›j = 1/{exp[β(ϵj – μj)] – 1} there appears the chemical...
01 January 2016 8,319 6 View
A gas consisting in identical bosons, say, atoms with integer spin, obeys at sufficiently low temperatures the Bose-Einstein statistics. Let's assume for simplicity that the only relevant quantum...
01 January 2016 9,789 4 View
A well known formula in Feynman's path integral formalism is (1) K(rA, rB) = ∫ K(rA, rC) K(rC, rB) drC, where K(rA, rB) is the amplitude of probability to reach the position rB at the time tB,...
12 December 2015 5,142 62 View
Dear friends, Recently I was told about a so-called Beth experiment. But I am not sure of its description that I found in some article on Internet, so, I am asking the question. The configuration...
12 December 2015 4,237 5 View
Consider the following two statements: 1) by moving from one frame of coordinates to another one, in relative movement, the wave-function of quantum systems (including entangled systems)...
11 November 2015 2,306 58 View
It is known that bosons have a bunching tendency. Assume that the bosons are atoms of a gas in a magnetic trap. At high temperatures this effect is not obvious. But, if we decrease the temperature...
11 November 2015 7,203 20 View
This question is a follow-up of the question "What happens to a photon if sent into a cavity whose dimensions are not fit for the photon's...
10 October 2015 850 63 View
Consider a photon of wavelength λ which is sent to a cavity whose three dimensions, L, W, H, are not multiples of λ/2, see figure. Assume the cavity walls perfectly reflective.What will happen...
10 October 2015 8,383 44 View
Consider the following experiment: a source of slow electrons emits in the direction z wave-packets with a group velocity 1000Km/s. The wave-packets are of Gaussian form in all three dimensions,...
10 October 2015 6,002 55 View
We frequently ask what is the wave-function. Some people are satisfied with the answer that the wave-function is the solution of the Schrodinger equation, but this answer just transfers the...
07 July 2015 7,185 6 View
I am no specialist in the topic of neutrino flavor oscillations, but I examined a lot of articles, theoretical and experimental, on this topic. And the result is that I remained with doubts on...
06 June 2015 1,386 81 View
The Bell inequalities proved that the correlations in entanglements don't originate from local hidden variables, neither from a common cause i.e. from some hidden variable distribution delivered...
05 May 2015 4,691 21 View
In his article from 1876 "On the State of Thermal Equilibrium in a System of Bodies with Consideration of Gravity", Loschmidt held, in contradiction with Maxwell, that given a vertical container...
05 May 2015 3,067 54 View
This question was inspired by the answers and discussions around a previous question, What does Loschmidt's paradox tell us about the second law of thermodynamics?...
05 May 2015 4,084 69 View
I saw a citation of an article of Robert Ehrlich, "Six observations consistent with the electron neutrino being a tachyon with mass: m2 ν_ e =−0.11±0.016(eV)2", http://arxiv.org/abs/1408.2804. I...
03 March 2015 6,099 10 View
This question is a reaction to the fact that some authors hold that the interaction between a microscopic object with a macroscopic object, leads to an entanglement between the states of the...
01 January 1970 3,629 56 View
There is an implication appearing in a lot of works on the measurement problem in QM: (1) |S> |M0> = ( Σj αj |sj> ) |M0> → Σj αj |sj> |Mj> where |S> = Σj αj |sj> is the state of the quantum...
01 January 1970 2,182 5 View
Consider the simple wave-function describing single particles (1) ψ(r, t) = 2-½[ψL(r, t) + ψR(r, t)], where the wave-packet ψL flies to the left of the preparation region, and ψR to the right....
01 January 1970 1,225 17 View
By QM I mean here both the relativistic and non-relativistic quantum mechanics. I saw very many questions and works posing the problem whether QM is a consistent and/or complete (closed) theory....
01 January 1970 9,596 30 View
Consider a particle detector whose principal component is a conteiner with monoatomic gas whose atoms do not interact, except by collisions. Assume that the conteiner walls are perfectly...
01 January 1970 2,822 4 View
The 2nd law of the thermodynamics says that the entropy only increases. From this law we derived a time-axis that has only one direction - forward. Similarly, from our life-experience we know that...
01 January 1970 5,954 95 View
BEFORE ANSWERING PLEASE READ THE TEXT! The problem posed here is to shorten the time measured by a traveller in his rest-frame, beyond the shortenning ensured by the Special Relativity. It seems...
01 January 1970 10,083 16 View