Questions tagged [terminology]
Use this for questions relating to the proper use of physics terminology or nomenclature.
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What is a stoquastic Hamiltonian?
Recently, I've often read about the term 'stoquastic Hamiltonian'. But I couldn't find a precise definition anywhere. I found that the Ising-Hamiltonian is a stoquastic Hamiltonian, but that does not ...
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What is the difference between material time derivative and total time derivative of a tensor field? [closed]
I consider material coordintes as $(X_1(t),X_2(t),X_3(t),t_0),$ ($t_0$ arbitrary) and space coordinates as
$(x_1(t),x_2(t),x_3(t),t).$
$\textbf{Remark.}$ I am interested just in dim=3.
We consider a ...
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Is there a relationship between the magnitude of the velocity and acceleration vector?
Given a path, how do the magnitude of the velocity and acceleration vector along the path correlate? I am confused due to the fact that the acceleration is the change of velocity over time and in ...
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What's the difference between hopping and tunneling?
My professor made a distinction between electron hopping (the closest wikipedia had an article on) and tunneling, saying that one (he didn't say which, but I assume hopping) was temperature dependent ...
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What is the difference between loudness, amplitude and volume?
i'm confused because some websites I've seen they are not the same, while my textbook says they're the same, and I'm trying to find the distinction between amplitude, loudness and volume.
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Symbol denoting parity eigenvalue
What is the symbol reserved for designating the parity of a parity eigenstate?
For example an eigenstate $\phi$ of the squared angular momentum operator $\hat{\mathbf{L}}^2$ is characterized by a ...
rob♦
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GR and Riemann Surfaces -- does the complex plane have anything to do with it?
I have only the vaguest understanding of Riemann Surfaces -- my sense is that Einstein used them in General Relativity because of their shape.
But Riemann Surfaces I think are not just deformations of ...
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Why is the term 'Accuracy of 1 part in $x$' used?
My question stems from how we measure the accuracy of Caesium clocks. Most Caesium clocks are said to have an accuracy of '$1$ part in $10^{14}$.'
I understand that the terminology means to convey ...
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What does the phrase "$s$-wave resonance" mean?
I saw the phrase "$s$-wave resonance" in various research articles:
"Comparison of average s-wave resonance spacings from proton and neutron resonances" by Vonach H, Uhl M, Strohmaier B, Smith BW, ...
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What are pre-collisions and post-collisions in forces and momentum?
What are pre-collision and post-collision exactly? I assume it is before collision and after collision. I can not find an answer on google.
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In an acoustic wave, what are the first order and second order perturbations?
From a reading of several articles like the one by Settness et al. $[1]$, there is an equation describing pressure and velocity fields to be combination of first order and second order terms. What do ...
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Why is the state of a quantum system called "Density $\textbf{Operator}$"?
In quantum mechanics, a $d$-dimensional pure state is represented by a vector belonging to a $d$-dimensional Hilbert space $\mathcal{H}^d$. A mixed state is represented by a density matrix $\rho \in \...
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Do even modes exist for e.g. pipes closed at one end?
This is really a question about terminology, The wavelength of a standing wave in a e.g. pipe closed at one end and open at the other is said to be $\frac{4L}{n}$, where $L$ is its length and $n$ is ...
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What are virtual and apparent forces?
Acceleration in a rotating frame can be written as: $$\underline{a}=\frac{\partial^2\underline{r}}{\partial t^2}+\frac{\partial\underline{\omega}}{\partial t}\times\underline{r}+2\underline{\omega}\...
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Absorption and emission spectrum terminology
Hi everyone recently i was looking for laser crystals and since I am an autodidact i was confused by the terminology and units of the optics domain. And specialy by the absorption and emission ...
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