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Questions tagged [bosons]

Bosons are integer-spin particles that obey Bose-Einstein statistics. Two bosons can occupy the same quantum state.

The name boson was coined by Paul Dirac to commemorate the contribution of the Indian physicist Satyendra Nath Bose in developing, with Einstein, Bose–Einstein statistics—which theorizes the characteristics of elementary particles.

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Why fermions have a first order (Dirac) equation and bosons a second order one?

Is there a deep reason for a fermion to have a first order equation in the derivative while the bosons have a second order one? Does this imply deep theoretical differences (like space phase dimesion etc)? I understand that for a fermion, with half…
Costantino
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Was X17 predicted before it was observed?

Articles, with very little detail, have made their rounds about an X17 boson (16.7 MeV) being observed in tests of decaying beryllium-8 and perhaps once in a test with helium. Most of the undiscovered particles that are searched for in CERN or other…
userLTK
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Meaning of the chemical potential for a boson gas

My lecturer told me that $\mu$, the Chemical potential, is zero or negative, and in the following example, mathematically it acts as a normalization constant. But is there any physical insight about why boson gas can be zero or negative? I think it…
el psy Congroo
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Huge confusion with Fermions and Bosons and how they relate to total spin of atom

I am supremely confused when something has spin or when it does not. For example, atomic Hydrogen has 4 fermions, three quarks to make a proton, and 1 electron. There is an even number of fermions, and each fermion has a 1/2 spin. Since there are an…
QEntanglement
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Why do bosons tend to occupy the same state?

It is often said that, while many fermions cannot occupy the same state, bosons have the tendency to do that. Sometimes this is expressed figuratively by saying, for example, that "bosons are sociable" or that "bosons want to stay as close as…
DoeJohn
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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.
Nick
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Are fermions and bosons fundamentally different?

Looking at various particles regarding being fermions or bosons, it seems to me that fermions are something fundamentally different from bosons. What I mean by "fundamentally different" is "as different as the electromagnetic force is to the strong…
Volker Siegel
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Are there Goldstone bosons in 1D or 2D?

The Mermin-Wagner theorem states that continuous symmetries cannot be spontaneously broken at finite temperature in systems with short-range interactions in dimensions d ≤ 2. And Goldstone bosons are new excitations that appear when there are…
João Bravo
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How can a massless boson (Gluon) mediate the short range Strong Force?

I thought massless particles were mediators for long range forces such as electromagnetism and gravitation. How can the massless gluon mediate the short range strong force?
user4884
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Is there a reason why the spin of particles is integer or half integer instead of, say, even and odd?

It seems to me that we could change all the current spin values of particles by multiplying them by two. Then we could describe Bosons as even spin particles and Fermions as odd spin particles. Is there some consequence or reason why we can't simply…
Kainui
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How do particles become entangled?

A person asked me this and I'm just a lowly physical chemist. I used a classical analogy. (How good or bad is this and how to fix it?) Basically, light has a net angular momentum of zero, insofar as it is not polarized into its left and right plane…
user24635
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Do composite-boson-states live in symmetrized or antisymmetrized Fock Space?

An even number of fermions make up a boson. Is this state described by a vector in antisymmetrized (fermionic) Fock space, where the resulting vector can somehow be connected to a bosonic state, or is it empirically motivated that an even number of…
Michiel
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Can He-4 atoms create black holes?

Suppose that in the intergalactic space far from any significant gravitational attractors there is a relatively small concentration of He-4 atoms. Due to gravitational attraction fermions in this case would form a sphere (gas planet), but as bosons…
Ardath
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Does the Pauli exclusion principle apply to mesons?

According to the Pauli exclusion principle, two identical fermions cannot occupy the same quantum state simultaneously, but two bosons can. Mesons are bosons, but composed of two quarks, and quarks in turn are fermions. If two identical mesons were…
hilssu
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Combining two finite number fock spaces into one

Say I have two separate systems of identical Bosons, one with N Bosons the other with M. System one is described by a state $|\psi_1\rangle$ the other with $|\psi_2 \rangle$ which are expressed in a Fock space like $|\psi_1\rangle =…
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