Questions tagged [particle-physics]

Particle physics is the study of the fundamental forces of nature as they are embodied in the interactions of elementary and composite particles at high energies and short time and distance scales.

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How does a spring's maximum compression ratio change with decreasing it's free length for a coiled helical spring(compression)?

I'm just looking for a simple expression formula for how maximum spring compression changes with free length of a coiled helical spring, say a Compression spring. A way of understanding what I mean by ...
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Did I understand RG correctly?

I am currently self-studying Renormalization Group (RG) in Condensed matter physics (in preparation for graduate school while I'm in Alternative Military Service). While I'm writing bunch of ...
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1 vote
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Energy and Momentum conservation in Bhabha scattering

I came across this question here which was asking my exact initial question (I even came from Griffiths problem 2.4 too!). But the given answer gave me a lot more questions which I think constitute ...
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1 vote
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How was Potassium used to estimate the effect of backgrounds in the Homestake experiment?

I'm trying to understand some of the details of the Homestake experiment, which attempted to measure the rate of neutrino production by the sun. In particular, I'm interested in how Davis et. al. ...
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If Mass Defect for a Stable nuclei is positive, why is its packing fraction negative?

Mass Defect = Mass (Initial : Mp + Mn) - Mass(Final : Observed) So if Mass Defect is positive, it means the nucleus is stable. But it is known ...
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Parity and intrinsic parity definitions

The action of parity operator on wavefunctions is defined as a reflection in the origin $$\hat{P}\Psi(\boldsymbol{r},t)=\Psi(\boldsymbol{-r},t)$$ In particle physics, though some books define its ...
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Which neutral atom-based quantum sensor is hardest to build/operate?

I am currently going through the presentation, "Sensing with neutral atoms", by Grant Biedermann. I understand that, according to the talk, there are a large number of different sensing ...
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What is the role of Hermitian Hamiltonians in relativistic QFT?

In single-particle quantum mechanics, the probability of finding the particle in all space is conserved due to the hermiticity of the Hamiltonians (and remains equal to unity for all times, if ...
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How to test for possible negative mass of dark matter?

What is the phenomenology of how to test if dark matter has possibly a negative mass (WP negative mass) in particle physics experiments, cosmology or astrophysics? I lately came across this ...
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Why were sparks created in Rutherford's alpha particle scattering experiment?

So I just read that when alpha particle hit the gold foil sparks were created. And these flashes were used to determine the angle of scattering. So were the sparks created because the alpha particles (...
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Do microwaves make polar molecules spin or vibrate? [duplicate]

I’ve been reading about how microwave ovens heat up your food and I keep finding conflicting answers (some say it vibrates, others say it spins). On the one hand, I’ve also read that heat is the ...
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Vacuum Transitions and Lorentz Symmetry Breaking

There are many "bumblebee" models 1, 2 where Lorentz invariance is violated usually resulting from a local vector or tensor field acquiring a nonzero vacuum expectation value We do not know ...
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Why does production of electron come with either electron neutrino or positron?

I read that when an electron is produced, it always comes either with an electron neutrino or with a positron. Why is that so? Why doesn't an electron come instead with say a muon neutrino or antimuon?...
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Fusion energy origin

In fusion , I have understood so far that two light nuclei fuse to form a heavy nucleus. The nucleons in the light nuclei experience lesser binding energy as compared to the nucleons in heavy nucleus ...
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