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My most favourite subatomic particles are the electron,the quark(up,down down, strange, charm, bottom, top, and the antimatter equivalents of those) and the positron.What about yours?

Electron: the only particle you can do DIY manipulation with

string, not the c-string but superstring. I also like the idea of SUSY and higgs boson.

The tachyon, by a long shot. Both because I could escape the madness that is office work faster than light, and because I could travel back to strangle a few people before they do their dirty deed.

I know, I know, I know that's not what tachyons are about. It's a joke, OK?

My **** =)

Combuster wrote:Electron: the only particle you can do DIY manipulation with

Actually I did that just today with free electrons in a teltron tube which I showed to my students I guess they were quite happy watching that thin orange beam inside the tube.

But my favorite is the graviton Even though it might be not as nice as the other gauge bosons...

My favorite particle is Photon since:
1. It is the form of pure energy.
2. It is strange particle which is antiparticle to itself.
3. It is the base of Theory of relativity.
4. It is the source of low entropy (not an energy! that's common mistake!) that bring the life to the Earth.
5. It is one of the most obvious physical implementation of complex numbers and the evidence of reality of such mathematical abstraction as imaginary unit.
6. It is the only objects that has zero self-time and simultaneously travels from past to future and from future to past in the same form (see CPT symmetry). According to this, the any annihilation reaction is just an impact of photon travelling from future to past with a particle travelling from past to future, and after the impact the particle begins to travel to past (become antiparticle) and photon travels to future.
7. It is the particle that demonstrates the brake of the speed of light by momentarily changing the state of entangled particles independent of the distance between them. Although it is proven that this paradox could not be used for transmission of information.
8. This unique particle acts on all scales of physical world, from subatomic to Universe-wide.
9. This particle brings most of information to us and fills the nature with beauty and colors.

Yoda wrote:My favorite particle is Photon since:
3. It is the base of Theory of relativity.

Surprisingly, speed of light is not a requirement for relativity, but rather it's a consequent if you looking for a meaningful universe.
Tom Roberts has an interesting paper which deduce the speed of light(and other possible topology of universe) with just four postulates.
* The mapping postulate
* isotropy / homogeneity
* relativity postulate (note this is not refer to the theory of relativity, see the paper for detail)
* the group postulate

http://groups.google.com/group/sci.phys ... %27s+paper

bluemoon wrote:Surprisingly, speed of light is not a requirement for relativity, but rather it's a consequent if you looking for a meaningful universe.

Thank you for that link! It is very interesting. I always believed for that! Also I suppose (at intuitive level, but, of course, without theoretical proof) that a Big Bang and a global evolution of Universe are also theoretically predetermined within mathematical basis of relativity, symmetry, isotropy and homogenity with addition of global synchronization. But this is (if it is so) very complicated work beyond of my possibilities.
I meant that the light is the historical basis of theory of relativity. At present photon is the only particle proven to be massless and hence an easy experimental foundation for that theory.

Yoda wrote:1. It is the form of pure energy.

Since mass and energy are essentially the same, this applies to all other particles as well. Maybe one should rather say "It has zero rest mass.", which is probably what you mean by "pure" energy.

2. It is strange particle which is antiparticle to itself.

This applies to some other particles as well, such as the Z boson, the Higgs boson and the hypothetical graviton.

5. It is one of the most obvious physical implementation of complex numbers and the evidence of reality of such mathematical abstraction as imaginary unit.

What exactly do you mean by this? Complex numbers can be used in many areas of physics. However, they are not more or less "real" than "real numbers". Both are just a language for formulating physical laws in terms of formlas.

6. It is the only objects that has zero self-time and simultaneously travels from past to future and from future to past in the same form (see CPT symmetry). According to this, the any annihilation reaction is just an impact of photon travelling from future to past with a particle travelling from past to future, and after the impact the particle begins to travel to past (become antiparticle) and photon travels to future.

This is actually very similar to 2. due to CPT symmetry and applies to some other particles (like the Z boson) as well.

7. It is the particle that demonstrates the brake of the speed of light by momentarily changing the state of entangled particles independent of the distance between them. Although it is proven that this paradox could not be used for transmission of information.

This famous experiment can also be done with other particles. For example, particle accelerators / colliders can produce "entangled b-quark states", consisting of two mesons, one of them containing a b-quark, the other containing an anti-b-quark. However, it is undetermined which of them contains the b-quark and which contains the anti-b-quark unless you measure the decay of one of them into other particles. (It works with s-quarks, too, but nowadays one rather uses b-quarks because they give a clearer signal in the detector.)

At present photon is the only particle proven to be massless and hence an easy experimental foundation for that theory.

Except for the graviton. Even though it has never been observed directly (and it is not even clear how to theoretically describe it correctly), measurements of gravity can already determine some of its properties, such as spin 2 and mass equal to zero with high accuracy.

Yoda wrote:6. It is the only objects that has zero self-time and simultaneously travels from past to future and from future to past in the same form (see CPT symmetry). According to this, the any annihilation reaction is just an impact of photon travelling from future to past with a particle travelling from past to future, and after the impact the particle begins to travel to past (become antiparticle) and photon travels to future.

Photon don't has proper time. I think annihilation do not fit on it, since they just pass by each other. They may interfere, however, if there was annihilation, it's possible for two high energy photon to annihilate into other particles. Note that we are not talking about high energy photon excite other particle and create something, which is different story.

Ahaaaa! Interesting talks started with clever guys

XenOS wrote:Since mass and energy are essentially the same, this applies to all other particles as well. Maybe one should rather say "It has zero rest mass.", which is probably what you mean by "pure" energy.

One is the consequence of other. On interactions photon will loose it's energy transferring it to other particles while it disappears at all.

XenOS wrote:

2. It is strange particle which is antiparticle to itself.

This applies to some other particles as well, such as the Z boson, the Higgs boson and the hypothetical graviton.

I didn't say that it is the only such particle. Also, Higgs bosons and gravitons are still hypotetical and Z boson is heavy and has very short lifetime.

XenOS wrote:

5. It is one of the most obvious physical implementation of complex numbers and the evidence of reality of such mathematical abstraction as imaginary unit.

What exactly do you mean by this? Complex numbers can be used in many areas of physics. However, they are not more or less "real" than "real numbers". Both are just a language for formulating physical laws in terms of formlas.

I meant Schrödinger equation and the historical role of photon in quantum physics. Of course, complex numbers are widely used at present in describing the propagation of waves.

XenOS wrote:This is actually very similar to 2. due to CPT symmetry and applies to some other particles (like the Z boson) as well.

Z boson is the only other particle found experimentally, but, AFAIK, not in annihilation reaction. So, only photon annihilation is proven in practice.

XenOS wrote:This famous experiment can also be done with other particles. For example, particle accelerators / colliders can produce "entangled b-quark states", consisting of two mesons, one of them containing a b-quark, the other containing an anti-b-quark.

I never heard about similar experiments with other particles. It seems that unlike photons that experiments are too complicated to conduct them in practice.

XenOS wrote:

At present photon is the only particle proven to be massless and hence an easy experimental foundation for that theory.

Except for the graviton. Even though it has never been observed directly (and it is not even clear how to theoretically describe it correctly), measurements of gravity can already determine some of its properties, such as spin 2 and mass equal to zero with high accuracy.

The existence of graviton is still not proven. Anyway even if graviton will be found, the relativistic effects may easily be observed on photons but not easily on gravitons.

bluemoon wrote:I think annihilation do not fit on it, since they just pass by each other.

I wrote about annihilation of particle with antiparticle bringing two photons.

Yoda wrote:Also, Higgs bosons and gravitons are still hypotetical and Z boson is heavy and has very short lifetime.

From a certain standpoint, the lifetime of a photon is quite short, too, no?

Solar wrote:From a certain standpoint, the lifetime of a photon is quite short, too, no?

But you can't place yourself to that standpoint, no?

Who am I to judge a photon?

And since I don't judge, I don't even have to decide if it's a wave or a particle that I don't judge.