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-4
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0answers
35 views

Is there a particle that creates time [closed]

I recently read a metaphor for how higgs bosson gives mass to matter. "The higgs boson creates a higs field which passes throug all matter in the universe and gives it mass like an objecting passing ...
4
votes
2answers
59 views

How is the conservation of momentum satisfied in long-range attraction such as electromagnetism and gravity?

I'm not a physicist, but my understanding is that electromagnetism (including attraction between opposite charges) is mediated by the photon, and gravity is probably (hypothetized to be?) mediated by ...
0
votes
0answers
35 views

W boson one loop electroweak contribution to muon g-2

I want to calculate the one loop W boson contribution (triple gauge boson vertex WW-Photon) to the muon anomalous magnetic moment g-2 with the help of Dimensional Regularization. Diagram given below: ...
2
votes
0answers
56 views

Nature of particle spectra at ALICE

I have a question regarding the nature of the particle spectrum at ALICE as a function of momentum. The spectra in question can be seen here. My question is, why is it that the particle spectrum in ...
2
votes
2answers
56 views

What are the “generations of matter”?

After a series of clicks on New Scientist and Wikipedia, I ended up on the Wiki article for "generations of matter", and I didn't quite understand it. I believe (and this may be wrong) that different ...
5
votes
1answer
967 views

Is a photon technically a set of two particles?

When looking at the classification of massless particles, one finds that there is the (half-integer) quantum number "helicity" $h$. For every possible $h$ there is a certain particle kind. In the case ...
15
votes
6answers
2k views

What happens before a radioactive element decays?

What happens to a radioactive element just before it decays? In school, I've been told that the decay process of an element is absolutely random, and it is impossible to determine which unstable ...
1
vote
1answer
63 views

In what sense are photons emergent?

Recently I read in an essay by Wilczek: "Photons are mixtures of weak B3 and hypercharge C mesons. It is those objects, not the emergent photon, whose properties are ideally simple." Until now I ...
0
votes
1answer
38 views

What are the building blocks of objects? [closed]

We are always told everything is made of atoms, but that seems to me to be a to vague response. The atom is the smallest construction block for all things; if this is true, what are all the other ...
1
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2answers
55 views

Number of different massless particle an odd number

Why are there only three massless particles and not four? I thought for each kind of matter particle there is a corresponding particle. What makes this any different from everything else?
3
votes
1answer
78 views

Thickness of electromagnetic waves

Radio wave photons and light photons have a different wavelength. But they also appear to have a much different "thickness" in that light photons "fit" cleanly through small pigeonholes, where the ...
0
votes
2answers
80 views

How many elementary particles are there?

I was reading QED by Feynman (a dated book) and he seemed to be suggesting we have discovered hundreds of particles. But I thought there were only the ones we saw in the standard model (ie leptons, ...
-1
votes
1answer
109 views

Synchrotron radiation and special relativity

My questions below are for all those who assume the point-like electron of special relativity, that strange entity with no inner structure (!), but with intrinsic (?) rest energy, magnetic moment and ...
-3
votes
1answer
129 views

Emission and absorption of photons by electrons [closed]

Two questions occur at a critical review of the two famous experiments devised by Millikan in 1914, respectively Duane, Hunt and others in 1917-1920, which confirmed the action constant calculated by ...
3
votes
4answers
953 views

Must Matter Particles Have A Hard Edge?

It's my understanding that electrons are particles, and it's also my understanding that their location while orbiting an atom cannot be determined precisely and must be determined by statistics and ...
6
votes
4answers
1k views

Are atoms made of protons, electrons and neutrinos?

If neutrons decay into proton, electron and (anti)neutrino of electron type, then is it safe to say that atoms are protons, electrons and neutrinos?
7
votes
2answers
105 views

Can an elementary particle be reduced to its properties?

For instance, is an up quark merely its particular mass, 2/3 electrical charge and 1/2 spin? I was wondering if there was a 1:1 correspondence with a particle and its properties, but I noticed a gluon ...
8
votes
2answers
131 views

What are fundamental dimensions used to describe the physical universe? [closed]

I have heard that the universe can be explained in terms of the four fundamental forces. I have also heard it can be explained in terms such as space, time, energy, mass or even motion. To further ...
0
votes
1answer
41 views

If matter and antimatter were produced equally during the big bang, where is the rest of the antimatter? [duplicate]

As far as my understanding goes, during the 'Big Bang' equal amounts of matter and antimatter (matter's oppositely charged twin) were produced, and the physical matter that remains within this ...
2
votes
3answers
136 views

Self-energy of electron from classical reasoning

If it takes energy to group charge together(self energy) how can it be possible for every single electrons, etc, to have exactly same amount of charge? (think of if we hold some sand in our hand, then ...
4
votes
2answers
152 views

How does electron spin change instantaneously without violating inertia principle?

The inertia in one of the main properties of matter. That is why all process in macro world do not happen instantaneously. What I do not understand is how we should apply this general idea of inertia ...
4
votes
1answer
104 views

Why should I believe that “elementary” particles are indeed elementary?

Atoms were once thought to be indivisible (i.e. have no substructure), until it was discovered that they are made of protons and neutrons. Protons and neutrons in turn are made of quarks, and that's ...
3
votes
0answers
38 views

Are the electric charges of an electron and a proton equal or approximately equal? [duplicate]

I read in Auletta's quantum mechanics (section 11.2) that the charge of the proton is, apart from the sign, approximately equal to that of the electron.. What ...
1
vote
0answers
26 views

Conservation of charge on Higgs production by bremsstrahlung

The Higgs production channel $$q+\bar{q} \rightarrow W^++ H^0,$$ depicted below, seems to be violating charge conservation, or am I missing something? The quark and its antiquark have the same ...
3
votes
1answer
101 views

Magnetic moment of uncharged particles

As we know that particles, only having charge, can have magnetic moment, then how particle like neutrino (having mass) can have magnetic moment? Don't bother about neutron because it has charge ...
16
votes
3answers
2k views

An electron has no known internal structure, does that imply it has an unknown one?

I'm currently reading Alonso and Finn's Electromagnetism book. It explains that the spin contributes to the magnetic moment and is somewhat comparable to a rotation of the particle around its own ...
0
votes
2answers
155 views

What does temperature look like at the subatomic level?

I am trying to get a better understanding of the definition of temperature at the subatomic level. I have a background in molecular biology with some college physics, but no deep quantum mechanics ...
1
vote
1answer
48 views

Does quark have fixed energy?

Does a quark, for example a up-quark has a fixed energy? The standard model gives well defined masses in MeV which is energy too.
2
votes
0answers
60 views

Young Tableau Projectors: Does the order of symmetric and anti-symmetric projectors matter?

Given a Young Tableau we find the irreducible basis of an arbitrary tensor by projecting, The projectors are usually defined as first symmetrise over the row entries and then anti-symmetrise over the ...
31
votes
6answers
4k views

Do electrons have shape?

According to the Wikipedia page on the electron: The electron has no known substructure. Hence, it is defined or assumed to be a point particle with a point charge and no spatial extent. Does ...
25
votes
5answers
2k views

Is the graviton hypothetical?

Wikipedia lists the graviton as a hypothetical particle. I wonder whether graviton is indeed hypothetical or does its existence directly follow from modern physics? Does observation of gravitational ...
2
votes
1answer
111 views

Is it possible to measure the radius of an elementary particle?

The only way to describe the electron radius that I found in literature is the "classical electron radius". Is it possible to experimentally measure this? Is there a better way to describe the ...
0
votes
0answers
71 views

Which particles can go right through the atom?

Can elementary particles (like the electron, photon, or neutrino ) go through an atom (not the nucleus)?
3
votes
1answer
192 views

Rigorous mathematical formalism of particle physics

Can anyone provide me with a rigorous mathematical definition of the fundamental particles (all fundamental bosons and fermions), reflecting the analogy of action of groups with interaction of ...
-7
votes
2answers
457 views

Which is the heaviest elementary particle? [closed]

Which elementary particle has the greatest rest mass? (For the sake of this question I'll call a photon's rest mass 0, whether it is or isn't [actually, tell me if this is the right thing to do]).
4
votes
0answers
227 views

Nature of Microscopic space-time

I am going through the introductory chapter's of Schwinger's Source theory. He writes, It [Source Theory] is a phenomenological theory, designed to describe the observed particles. No speculations ...
1
vote
0answers
83 views

Fundamental difference between neutron and proton

As I try to understand the elementary particles,I was reading strong interactions and Isospin from a book.Then I came across this: Thus,the strong interactions do not distinguish between a proton ...
-1
votes
1answer
72 views

Lifespan of particles

After reading a very informative tutorial on elementary particles physics over at http://www.particleadventure.org, I have a question I can't figure out. I understand the need to accelerate a ...
0
votes
0answers
72 views

What is the most fundamental peice of matter? What is it that thing which can no more be sub-divided?

I know that there is theory that strings are the most fundamental particles. But if it is a string, then it can be 'cut' into pieces, and if it can be 'cut', then it can be cut at infinitely many ...
1
vote
2answers
75 views

Quarks are now considered to be fundamentals, but so were atoms some time ago. So the way we see is only limited by our technological advances? [duplicate]

After watching this FuseSchool - Global Education episode, I cannot stop thinking how can something not have a substructure, how it cannot be split? http://www.youtube.com/watch?v=nlv06lSAC7c
0
votes
2answers
113 views

Are particles solid?

My intuitive understanding is that although atoms are mostly empty space, the nucleus is solid. Thus a neutron or a neutrino can collide with it and do things like deflect or cause a nuclear ...
2
votes
1answer
145 views

What is the difference between QFT and elementary particle physics?

I'm a little unclear as to how QFT differs from Elementary particle physics. They both use pictorials of Feynman graphs, is it that Elementary particle physics assumes the point particle perspective, ...
1
vote
1answer
122 views

Elementary particles

That's what Wikipedia says about Elementary Particle: In particle physics, an elementary particle or fundamental particle is a particle whose substructure is unknown, thus it is not known to be ...
1
vote
2answers
137 views

Can we make usable energy from subnuclear particles?

I understand mass and energy are the same, but in this question I will be talking about mass being turned into usable energy (electricity/heat/etc). We can make our energy through chemical reactions ...
-1
votes
1answer
72 views

Muons Internal Clocks and Time Dilation? [closed]

I don't get how time dilation affects the half-life of muons? Time is just a tool that is used by humans how does that affect the internal clocks of elementary particles?
7
votes
1answer
720 views

Explaining chirality for spin 1/2 particle

I found the following explanation for chirality for spin 1/2 particles here What happens when you rotate a left- vs right-chiral fermion 360 degree about its direction of motion. Both ...
1
vote
5answers
234 views

Do the particles made in a collider exist outside the collider?

Below is the transcript of a section from Demystifying the Higgs Boson with Leonard Susskind. Around 1:02:23 Susskind says that the heaviest of the fermions is called the top quark. Top quark is ...
-3
votes
1answer
215 views

Has the spin and parity of the Higgs boson been experimentally confirmed? [closed]

I read in a newspaper that the Higgs boson might be the new boson but that this was not confirmed, because we don't know its properties, e.g. its spin or parity. Now I see it confirmed that it is the ...
13
votes
3answers
403 views

Why are all force particles bosons?

All of the force-particles in the standard model are bosons, now my question is pretty short, namely: Why are all force particles bosons? This can't be a coincidence.
4
votes
2answers
388 views

Is there scale by size of all discovered particles?

Atom: Neutron: Elementary particles: Is there scale by size of all discovered particles? From neutron and proton to electron and to boson? Compare to each other, like this I have found ...