# All Questions

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### Can we use the LHC to place an upper limit on possible space time uniformity

From wikipedia "X-ray and gamma-ray observations of quasars used data from NASA’s Chandra X-ray Observatory, the Fermi Gamma-ray Space Telescope and ground-based gamma-ray observations from the Very ...
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### How exactly does atmospheric pressure work?

Imagine a smooth wheel. Now imagine it is divided up into four "pizza slices". We came up with an idea where you would put the bottom two "slices" along with the top left "slice" in a very low ...
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### Is the Hall coefficient a resistance?

The Hall coefficient is defined as this: $$R_H=\frac{E_y}{j_xB_z}$$ Always as $R_H$. I am currious as to how to use this coefficient? Is it the y-direction resistance/resistivity (it is very close ...
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### Gravitational Collapse

Consider a spherically symmetric cloud of mass $M$ with radius $R$ and uniform density $\rho$. The gravitational collapse is governed by Newton's second law \ddot{r} = - ...
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### Chromatic aberration in human eye

A lens focuses the different colours of white light at different points. Since our eye has a convex lens there should also be such an aberration but we see objects clearly with normal eye. I want to ...
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### According to the Standard Model, did all the quantum fields originate from a single field?

I mean the electron field, electromagnetic field,... were all of them unified into a single field?
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### Is there any tension in a massless spring that connects two free falling bodies in different horizontal planes?

Two bodies A and B of same mass $m$ are attached with a massless spring and are hanging from a ceiling with a massless rope. They are in same vertical plane but not in same horizontal plane. Now the ...
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### Why can't we precisely define physics?

While reading a textbook, I came across this statement: "A precise definition of physics is neither possible nor necessary." I was curious why it is not possible but the textbook never ...
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### Is it possible to calculate the energy of a spark?

I am not a physicist, but this question came to me and I need to answer it, and I think that you guys can help me. Actually my question is just like in the title. Is it possible to calculate the ...
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A radio galaxy has giant radio lobes, each of the approximate diameter 20kpc. Protons of up to 9$\times$1019 eV remain trapped inside these lobes. What is the magnetic field that confides them? I ...
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### “Derivation” of the Heisenberg Uncertainty Principle

Ok, so I posted this in the mathematics StackExchange, but got no response. The question I outline below is my textbook's "derivation" of the Heisenberg Uncertainty Principle. The "derivation" my ...

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