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3
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0answers
226 views

what interactions would take place between a free proton and a dipolariton?

What interactions can be expected to take place between a free proton and a dipolariton, (a) at high energies and (b) at lower energies? A dipolariton is a bosonic quasi-particle mentioned in a ...
2
votes
1answer
265 views

A question regarding particle trajectories in the symplectic manifold formalism

How to solve a free particle on a 2-sphere using symplectic manifold formalism of classical mechanics ? Is there a way to get coriolis effect directly, without going into Newton mechanics? And is ...
1
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4answers
854 views

Questions on wave-particle duality

Wave-particle duality states that a particle has both wave properties and particle properties when one is not observing it. 1) What is an observer? Need it be anything living or can other particles ...
2
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2answers
308 views

How the nucleon structure has been identified experimentally?

It is known that nucleons (proton, neutron) are composed of partons (quarks, etc.). How was this identified experimentally? In particular, how it has been identified that nucleons comprise of more ...
18
votes
3answers
2k views

Are elementary particles actually more elementary than quasiparticles?

Quarks and leptons are considered elementary particles, while phonons, holes, and solitons are quasiparticles. In light of emergent phenomena, such as fractionally charged particles in fractional ...
7
votes
2answers
1k views

Do particles and anti-particles attract each other?

Do particles and anti-particles attract each other? From the very basic understanding that they are created out of nothing mutually and collide to annihilate each other seems to indicate this happens ...
1
vote
1answer
240 views

Stability of neutron [duplicate]

Possible Duplicate: How come neutrons in a nucleus don't decay? It is known that free neutron decays in 15 minutes on average. Why is it much more stable when "placed" in nuclei? Edit: ...
8
votes
1answer
869 views

why is there no ninth gluon?

A teacher of mine told me once that there were no ninth gluon because such a one should be white and interact infinitely far, and no one has been observed. Is there also a theoretical reason?
1
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0answers
32 views

GUT predictions for charm mass?

Most GUT models have some relationship between down-type quarks and leptons, that more or less agree with the observed values after running the renormalization equations. But, what about up-type ...
0
votes
2answers
199 views

Speed Distribution of The Particles

I want to know the distribution of the particles's speed. The particles what I mean are nucleons and electrons of element. Consume there is 1kg of iron on room temperature and it's shape is sphere. ...
3
votes
3answers
2k views

What is lepton number?

What exactly is a lepton number of a particle? With the charge (eg proton is just 1, not the exact charge), I can understand because it's a physical property, put a particle with charge + next to ...
3
votes
2answers
3k views

Speed of a particle in quantum mechanics: phase velocity vs. group velocity

Given that one usually defines two different velocities for a wave, these being the phase velocity and the group velocity, I was asking their meaning for the associated particle in quantum mechanics. ...
1
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2answers
2k views

Why does Davisson-Germer experiment confirm electron's wave-particle duality?

First I apologize if my question is trivial and for my poor English. I was wondering why my teacher states that "electron's wave-particle duality is verified if we observe diffraction of the electron ...
4
votes
1answer
733 views

Does the speed of sand flow in a hourglass depend on a height of a sand column above the hourglass neck?

In a hourglass, does the sand flow through the neck depend on the amount of sand in the upper glass? If we consider a sand flow analogous to fluid flow, then it should depend linearly, but in that ...
4
votes
2answers
767 views

What is the “shape” of atomic/subatomic particles?

I apologize in advance for my ignorance if this is a question with an obvious answer... I am not experienced in this field. But are such particles in the universe points with a charge, or are they ...
2
votes
2answers
169 views

What is a proton-rich atom?

http://wiki.chemprime.chemeddl.org/images/e/e4/Plot_of_Neutron_Number_vs._Proton_Number_.jpg The above graph shows that all elements have more neutrons than protons in this nucleus. So how is there ...
-2
votes
1answer
231 views

Transition of Electric Charge In Collision Between Proton And Antiproton

I know that $$p+\bar{p}\to 4\pi^++4\pi^-+(\gamma)$$ Before the collision, the sum of absolute electric charge value is $2$. $$\left | +1 \right |+\left | -1 \right |=2$$ After the collision, the ...
10
votes
2answers
2k views

How Did Paul Dirac Predict The Existence of Antiproton?

The existence of the antiproton with -1 electric charge, opposite to the +1 electric charge of the proton, was predicted by Paul Dirac in his 1933 Nobel Prize lecture. Quotation by Wikipedia. ...
5
votes
1answer
1k views

Confusion between the de Broglie wavelength of a particle and wave packets

So I learned that the de Broglie wavelength of a particle, $\lambda = \frac{h}{p}$, where h is Planck's constant and p is the momentum of the particle. I also learned that a quantum mechanics ...
4
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6answers
1k views

Good book about elementary particles for high school students?

I need a good book about elementary particles. I am a high school student and don't want anything to technical. I read a brief history of time and the universe in a nutshell but i want something that ...
1
vote
3answers
590 views

Can spin be infinite?

Can spin of a particle or a group of particles become infinity? Explain plz. Is there any representation for spins like dot(for $S=0$) and arrow (for $S=1$)? If so what for $S= \infty$?
9
votes
1answer
3k views

Standard Deviation in Particle Physics

I'm familiar with sigma, and how its usually calculated and used, but would like to know how it's applied to particle physics. I recall reading that the discovery of the Higgs would only be credible ...
13
votes
1answer
5k views

Phase shifts in scattering theory

I have been studying scattering theory in Sakurai's quantum mechanics. The phase shift in scattering theory has been a major conceptual and computational stumbling block for me. How (if at all) does ...
7
votes
3answers
385 views

Is there Bremsstrahlung radiation for a charged massless particle?

This is a follow up question from: Massless charged particles Since by definition such a particle would interact with photons- resulting in some change in momentum- would the particle emit ...
5
votes
6answers
662 views

What needs to happen for one to ingest radioactive particles and how likely is this?

There are many stories about radioactivity and the relative danger of it in the news lately, but very little actual information. The radioactivity levels around Fukushima Daiichi are high, but seem ...
7
votes
3answers
330 views

References on the non-compositeness of the known elementary particles

What paper(s) or theory(s) describe or prove that the elementary particles that we have determined today cannot be made up of smaller more fundamental particles?
5
votes
1answer
1k views

Why does lambda decay violate parity?

When a lambda particle decays into proton and a pion, I am told it does not conserve parity. Why?
5
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2answers
5k views

How do alpha and beta particles ionise surrounding particles?

I've been wondering about this question for a while. If you have alpha and beta particles released from a radioactive core, how do they ionise surrounding particles?
7
votes
2answers
2k views

Why can't massless particle exceed speed of light?

Why massless particle can't exceed speed of light?
3
votes
4answers
168 views

is the Z boson one entity or are there as many entities as decay pairs, but they are equivalent and lumped together

just wondering if it is a distinction without a difference - it seeming a bit weird that one thing can decay into different things.
6
votes
1answer
326 views

Unusual particle effects at CERN

In 2010 there were press reports that CERN had identified unusual properties in particle behavour in collisions. One link here. Here is a partial quote: "In some sense, it's like the particles talk ...
3
votes
3answers
2k views

are particles “knots” or “kinks” of excitation in a field?

this is my mental picture for how they travel without a medium, how (like water waves) some can't stay still, why they have wave and particle properties, energy/mass equivalence, conservation, etc. ...