Talk:Boson

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Many scientists determine bosons and fermions after theit spin value without explaining what is a cause for existing of this difference. Really, most of them know that the spin is a result of their inner motion. Some of this motions are determined by common coordinate, but others are determined by martices (bi-spinors) .As different common coordinates are commutative, then their inner oscillations along different oxes are independent and therefore they have a whole number h-bar spin. But other inner oscillations, which are determined by bi-spinors, which are no commutative, their oscillations along different oxes are strongly correlated and therefore they have a half number of h-bar spin. Consequently, if the inner oscillations are determined by commom coordinates, then their oscillations along differetn oxes are independent, then these excitations are bosons and if the inner oscillations are determined by bi-spinors, then their oscillations along differetn oxes are dependent, then these excitations are fermions.

So in a result of its inner motion the electric point-like electric charge make the own electric and magnetic fields of micro particle, then all fermions have zero values of electric intensity of own electric field in its moment plases and the double values of magnetic intensity of own magnetic fieldin some point and all bosobs have equal values of electric and magnetic intensities of their own electric and magnetic fields. Therefore the giromagnetic ratio of the magnetic dipole moment to the angular mechanical moment of the fermions are two times greater then this giromagnetic ratio fot their orbital boson motion.

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[edit] Corrections

I corrected a few mistakes in the article. For the record, Cooper pairs aren't bosons, since they can't meaningfully be considered as particles. _R_ 12:30, 7 Sep 2004 (UTC)

Cooper pairs are particles, or quasiparticles, if you wish, and they are bosons. Maliz 14:29, 2 November 2006 (UTC)

[edit] which is the defining property?

Please see the discussion at Talk:Fermion on whether spin or symmetry is the defining property of fermions and bosons. Fpahl 06:19, 8 Oct 2004 (UTC)

[edit] Bosons with even integer spin

We have all noticed that spin is described as being a multiple of hbar/2. I thought that it would be better to set this value to a constant giving,


hdot = hbar/2 = 5.2728584118222738157569629987­554e-35 J.s


But now the equations for spin did not work with hdot, so I had to correct them.

Here are the corrected equations,


|sv| = sqrt(s(s + 2)) * hdot


and


Sz = ms.hdot


where,


sv is the quantized spin vector,

|sv| is the norm of the spin vector,

s is the spin quantum number, which can be any non negative integer,

Sz is the spin z projection,

ms is the secondary spin quantum number, ranging from -s to +s in steps of two integers


For spin 1 particles this gives:

|sv| = sqrt(3).hdot and Sz = -hdot, +hdot

For spin 2 particles this gives:

|sv| = sqrt(8).hdot and Sz = -hdot, 0, +hdot


Now that the spin equations have been corrected, the definitions for fermions and bosons are incorrect, and must be redefined as follows.


Fermions are particles that that have an odd integer spin.

Bosons are particles that have an even integer spin.


Would these redefinitions have any other effects on the Standard Model?

Can these redefinitions explain any currently unexplained phenomena?

Are there any experiments that could confirm or refute these claims?


I would like eveyone to have a good think about this, and give me your objections to it, or even data to support it.

[edit] Dubious statements, lack of references

This article claims that Helium-4 and Sodium-23 and other nuclei are bosons. I think someone is confused; atomic nuclei are composed of quarks, which are fermions, not bosons. On the off chance that it is I who am confused, I've left these claims in and merely tagged them as disputed. This article completely lacks any authoritative references. I'm sure any reasonable modern quantum mechanics textbook could both resolve the dispute and act as a good reference. -- Beland 01:23, 16 August 2005 (UTC)

Nuclei with integer spin are bosons. Here's a reference, sorry about the poor source: "Bosons include mesons, nuclei of even mass number, and the particles required to embody the fields of quantum field theory." [1]. The issue isn't discussed in Gasiorowicz, I'll see if Sakurai has it. -- Tim Starling 03:26, August 16, 2005 (UTC)
Ah, I think I was confused about the dual senses of "integer-spin entity" and "elemental boson". That should definitely be more clearly explained. -- Beland 06:02, 16 August 2005 (UTC)

From Sakurai Modern Rev. Ed. (ISBN 0-201-53929-2) p362:

Even more remarkable is that there is a connection between the spin of a particle and the statistics obeyed by it:

Half-integer spin particles are fermions;
Integer spin particles are bosons.

Here particles can be composite; for example, a 3He nucleus is a fermion just as the e- or the proton; a 4He nucleus is a boson just as the π±,π0 meson.

The spin-statistics question is, as far as we know, an exact law of nature with no known exceptions. In the framework of nonrelativistic quantum mechanics, this principle must be accepted as an empirical postulate. In the relativistic quantum theory, however, it can be proved that half-integer spin particles cannot be bosons and integer spin particles cannot be fermions.

[edit] Bosons occupying the same physical space?

OK, now that that's settled, I have another question. Are composite bosons, made of fermions, subject to the Pauli exclusion principle? It's my understanding that you can have an unbounded number of elemental bosons, like say, photons, with the same properties, in the same physical space. It seems non-intuitive that fermions which experience exclusion, when assembled into composite baryons, cease to experience exclusion, especially with respect to physical location. But then, quantum mechanics is not necessarily intutive or sensical in the same way that classical mechanics is. Now, you don't see an unbounded number of helium-4 nuclei inhabiting the same physical space, but then again, they are electrically charged, and so experience electrical repulsion. What do the textbooks have to say about that? -- Beland 22:39, 5 September 2005 (UTC)

We need to make a distinction between He-4 nuclei and He-4 atoms, which are neutral. Maliz 14:41, 2 November 2006 (UTC)
  • Actually, Bose and Einstein said that a boson could meaning hypothetically occupy the same quantum state as other bosons. Normally, they don't. It is only in Bose-Einstein condensates that it was proven that they were right about bosons being able to occupy the same physical space or same quantum state.--Voyajer 19:41, 21 December 2005 (UTC)
So in fact any number of helium nuclei can actually occupy the same physical space at the same time? =:-O
An effective theory of He-4 atoms consists of atomic bosons with a pairwise repulsive van der Waals potential. It is precisely this repulsive van der Waals potential which prevents two He-4 atoms from occupying the same location in space. However, if we work in momentum space instead (the Fourier transform), two He-4 atoms can have the same momentum. This is precisely what we get in superfluid He-4. Admittedly, a He-4 atom is composite and the repulsive part of the van der Waals interaction comes from the exclusion principle of the electrons, but even if we have a hypothetical theory with a fundamental noncomposite boson with a repulsive potential at short distances, we still wouldn't find two bosons occupying the same location in physical space. Maliz 14:41, 2 November 2006 (UTC)

[edit] Bosonic field and Fermionic field articles

We need some help defining just what a bosonic field is, and what a fermionic field is. Please see the discussion pages for Bosonic field and Fermionic field. Thanks. RK 19:54, 21 May 2006 (UTC)

[edit] Sources?

  1. The nucleus of Deuterium, an isotope of Hydrogen
  2. Helium-4 atoms
  3. Sodium-23 atoms
  4. Any nucleus with integer spin

Can someone give me then source for this 4 types of bosons?GravityTalk 03:58, 30 December 2006 (UTC)

Helium-4 nuclei are bosons -- http://concise.britannica.com/ebc/article-9080816/bosons Bertrem 06:19, 14 February 2007 (UTC)

[edit] Are mesons bosons?

Are mesons bosons? I thought mesons were composed of quarks and anti-quarks, which are femrions, which would make mesons fermions, so they can't be bosons. I'm confused.24.21.139.41 15:47, 12 May 2007 (UTC)

A composite particle containing an odd number of fermions (quarks or leptons) is a boson. A composite particle containing an even number of fermions is a boson. Therefore, mesons are bosons.24.21.139.41 00:33, 14 May 2007 (UTC)
Mesons are composite bosons, just as baryons are composite fermions. Mesons mediate force; baryons make up matter. Both are made up of elementary particles, and those elementary particles happen to be quarks. -- TheEditrix2 16:02, 23 June 2007 (UTC)

[edit] Only other?

Up there in the intro is the seemingly out of place sentence "The only other boson is the Higgs..." One wonders: "only other"? How 'bout pions, gluons, W and Z bosons, gravitons, and 200-some "only others"? I'm tempted to chop the sentence entirely, but I don't know what was intended by the original author. Anyone able to weigh in? --TheEditrix2 15:58, 23 June 2007 (UTC)

[edit] Examples of Bosons

This has an ugly link to the main article, being "List of particles#Bosons (integer spin)". Would it no be better to do this the other way arround: move the content of that section of the of particles to this page and put a link there instead of here?

Also, the "basic properties" section already mentions most of the content of this section, it would make more sense to only mention things once. —Preceding unsigned comment added by 62.136.210.137 (talk) 01:24, 13 February 2008 (UTC)