Newest Questions
244,129 questions
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How can water with a very tiny change in density increase the pressure so much?
We have two tanks full of water, one is 1bar second is at 100bar.
In both tanks water has same density(tiny difference) and temperature, that mean same number of molecules(almost the same) at the ...
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BRST anticommutation relation and Virasoro generators [closed]
I have been bothered for couple days by how to derive (3.2.19) in Green, Schwarz, Witten's book <Superstring Theory volume 1>.
The formula is
$$Q^2=\frac{1}{2}\{Q,Q\}=\displaystyle\frac{1}{2}\...
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does a neutrino really a massful particle? [closed]
neutrinos mass problem ?
generally neutrinos mass problem became more terrific to me because as i studied in my class text books a neutrino is a particle which is either released in some decays and my ...
3
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The problem of the perfectly horizontal string
Suppose we have a piece of string, of non-zero mass, whose two ends are attached to two heavy blocks, where the two points of attachment have the same height measured from the ground.
In other words, ...
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When the frequency ceases to exist
As long as a frequency has a wavelength and an amplitude, it can be called a frequency.
If I look to the anatomy of a frequency, what happens if a frequency transforms to a wavelength reduced to 0? Or,...
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Apparent contradiction in wavelength of standing waves in an open-ended organ pipe
Recently I came across the "end correction" in organ pipes, and got to know that it affected only displacement waves, i.e it shifts the antinode of these displacement waves further outward.
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Is this a notational mistake?
I was reading Dirac's original paper from 1928, and I noticed this equation
Is it just me, or it's supposed to be
$$\rho_{mn} = -\frac{e}{2mc^2}\lbrace ih (\psi_m \frac{\partial \bar{\psi_n}}{\...
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Enthalpy of An Ideal Gas
I have started self studying statistical physics for a research project. I have a background in pure mathematics, and am having some trouble understanding differentials.
To learn, I am using L.E. ...
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Is the magnitude of error in a measurement inversely proportional to the number of observations taken?
I came across the following question.
A research worker takes 100 observations in an experiment. If he repeats the experiment by taking 500 observations, how is the probable error affected?
The ...
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Repulsive sheet through a uniform gas
I'm working on a pretty niche cosmological system where a (gravitationally) repulsive "sheet", say parallel to the xy plane, is moving through a uniform gas with temperature $T$ and density $...
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In quantum mechanics, why is the perturbed state orthogonal to the unperturbed state?
In perturbation theory, we may write the full wavefunction as
$$|\Psi\rangle = |\psi^0\rangle + \varepsilon |\psi^1\rangle + \mathcal O(\varepsilon^2).\tag{1}$$
Here I'm focusing on a single energy ...
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Dog chasing a cat problem: Minimum distance [closed]
A cat sitting in a field suddenly sees a standing dog. To save it's life cat runs away in a straight line with constant speed u . Without any time lag, the dog starts with same constant speed u. At ...
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How can a superdeterministic universe deal with (classical) chaos?
I'm aware that "superdeterminism" is sometimes misinterpreted, so I just want to provide a bit of context about how I understand the term:
When I was first learning about how a "hidden ...
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Will quantum computing trigger a cryptocurrency boom or crash? [closed]
I asked Microsoft Copilot and this was its response:
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Will quantum computing trigger a cryptocurrency boom or crash?
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Quantum computing could have a major impact on cryptocurrency, but whether it ...
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Does beat frequency work differently when the beat frequency is greater than one of the initial frequencies?
I'm studying beats right now, and I know that, given two waves, the beat frequency can be found by taking the absolute value of the difference between the frequencies of those waves. I assumed that a ...
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