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Questions related from L.D. Edmonds
Consider the case of negligible gravity but there is an accelerating reference frame. Its origin traces out a trajectory, or world line, seen in some inertial reference frame. The Lorentz metric...
25 July 2024 1,573 15 View
When reading the literature, I frequently encounter the assertion that the arrow of time is controlled by increasing entropy. But I never find an explanation of what physical system the entropy...
07 March 2024 8,613 13 View
I search the internet for quantum computing and find that it uses qbits. I search the internet for qbits and find that they are used in quantum computing. I'm not learning anything from that. Some...
02 February 2024 9,396 10 View
Elementary explanations of the second law of thermodynamics refer to probabilities of system states and seem convincing. But not when considering time-reversals, because the same statistical...
21 January 2024 3,200 18 View
One person, called the observer, is far from a black hole and is watching another person, called the victim, fall into the black hole, where "fall in" is defined by crossing the Schwarzschild...
30 December 2023 1,129 59 View
On one hand it seems that being required to report for jury duty is a violation of some kind of civil rights. On the other hand, this is necessary for the present-day justice system to work. How...
09 December 2023 9,930 0 View
I'm supposed to be able to figure this out and am embarrassed to be having a mental block right now. The answer is probably simple. Consider a loop or ring made of some rigid material. The loop...
04 November 2023 7,297 19 View
Consider the quantum mechanical (QM) problem of measuring the energy of some particle. No incompatible measurements are simultaneously made so there is no theoretical limit on how accurate the...
01 November 2023 2,939 35 View
When I look up the definition of a Lie group I find that it is a differential manifold. When I look up the definition of a manifold I find that it is a space that is locally Euclidean. My...
13 October 2023 6,528 5 View
I am trying to learn modern physics and frequently encounter the phrase "gauge theory". I look up the definition and find that it is a theory in which a Lagrangian is invariant under a certain...
09 July 2023 7,631 5 View
The topic considered here is the Klein-Gordon equation governing some scalar field amplitude, with the field amplitude defined by the property of being a solution of this equation. The original...
05 March 2023 6,424 6 View
Start with a purely classical case to define vocabulary. A charged marble (marble instead of a point particle to avoid some singularities) is exposed to an external electromagnetic (E&M)...
19 February 2023 6,668 3 View
I usually ask more scientific kinds of questions, but this concerns me. The lifespan of humans is not long enough, in my opinion, but dogs get even less. Most dogs don't live past 16 years. The...
12 February 2023 7,925 10 View
Consider the quantum field theory (QFT) operator (an operator for each space-time point) that the field amplitude becomes when making the transition from classical field quantities to QFT...
04 November 2022 5,215 16 View
In the elementary quantum mechanics (QM) of a single particle responding to a given environment, the state of the particle can be specified by specifying a set of commuting (i.e., simultaneously...
03 November 2022 8,221 7 View
The definition, that I have learned, of the determinant of a matrix is a set of instructions on how to calculate its value. This definition can be put in equation form if we keep track of odd...
26 December 2020 4,964 13 View
I am a novice that needs help with a topic that probably seems elementary to more experienced people. The case considered is a mass M sitting on Earth’s surface. Throughout this discussion,...
19 September 2020 5,062 56 View
Consider a system of two particles. The system was prepared (e.g., by some prior measurement) to have zero total spin. Another measurement is made, either immediately after the preparation or at a...
22 February 2020 5,801 4 View
Some theorems can reach a conclusion when the derivative of some real-valued function of a real variable is continuous, and some other theorems can reach a conclusion if the derivative merely...
17 August 2018 8,619 2 View
I have a set of measured data points that empirically defines a function of two variables. I need to fit this data set with a nonlinear analytical function that is given but it contains five...
09 October 2015 5,359 21 View
I am trying to find a table of the energy absorption coefficients (or mass energy absorption coefficients, I don't care because I can convert) in silicon dioxide for a variety of photon energies...
07 August 2014 3,469 14 View
