Massless Energy & Nothing.

[Qfwfq]

It gives the equation to work out the speed of light:

 

Speed of the wave = (distance between peaks) * (frequency)

 

= (wavelength) * (frequency)

This would be phase velocity, which may be greater than c in a dispersive medium. The "real" speed is group velocity.

 

As for index of refraction, it's important to understand that it reduces the speed at which EM waves travel, in a way which may depend on frequency, but this isn't the same thing as reducing c. Light may be travelling slower than another particle going through the same material. The limiting velocity, for anything causal, is still c.

[Damo2600]

Qwfwq,

 

So enlighten us then please, LMAO, what is an electron? We'll start this simply.

 

Sorry Web feet I have to say no because you see the trouble saying maybe gets me into. Physics is a very touchy subject... You'll learn that really soon. :Alien:

 

Lol

Damien

[Tormod]

The electron? Read up here:

http://en.wikipedia.org/wiki/Electron

 

As for the speed of light changing in different mediums, read up here:

http://www.rpi.edu/dept/phys/Dept2/APPhys1/optics/optics/node4.html

[Damo2600]

Qwfwq,

 

Thanks for pointing that out. He has just told me (for those who don't understand the technical dialogue of Qwfwq whom loves to dazzle the mind with his knowledge - it's really something by the way).

 

Phase velocity = the speed of the wave (one dimensionally)

 

Group velocity = the wave speed I have been talking about (two dimensionally)

 

Index refraction = the amount that light is bent when it enters the water (this has no effect on speed however due to the fact that light travels in water at a constant)

 

Then he goes on to discus Electromagnetic waves in a way which is not really relevant to the subject.

 

So there you go thanks a lot.

 

Damien

[Qfwfq]

what is an electron?

We know less about the "innards" of an electron than about those of a proton or neutron because, so far, leptons appear to have no "innards", they probably have none, we know their properties from the outside.

 

Protons and neutrons, otoh, have a diameter of about 1 fermi (10^-15 m) and are a more or less spherical distribution of quarks and antiquarks confined by gluons. Look up QCD for more, look up deep inelastic scattering, DIS, look up hadronic diffraction...

 

Unless, of course, you meant the Kant style noumena vs. phenomena issue. If you meant that, we know no more about what a table or a chair "actually is", LMAO.

[Qfwfq]

Then he goes on to discus Electromagnetic waves in a way which is not really relevant to the subject.

What is relevant to the topic? How about:

 

m^2 = E^2 - p^2

[Damo2600]

Yes Qwfwq,

 

What is a quark?

 

Damien

[Damo2600]

m = E - c

 

I've never heard that one. Very clever though. Does this subject annoy you some how?

[Qfwfq]

Uhm, if you don't like the c = 1 choice of units, multiply the m, the E and the p by c^2, and see what you get. Does it look slightly more familiar this way?

 

Not enough? Consider the case of p = 0 and see what you get (the square of).

 

Then consider another case, not p = 0 but m = 0.

 

Take the hint and ponder.........

[Qfwfq]

What is a quark?

Hark hark! A quark!

 

See "Quarks and Leptons" by Perkins. You can find it in the library of a good Physics faculty, it wouldn't be all that cheap to buy. You might find layman's stuff around too.

[Tormod]

Damo2600,

 

before you start being condescending towards other members perhaps you should try to do your research on your own before requiring us to do it for you?

 

Quarks:

http://www2.slac.stanford.edu/vvc/theory/quarks.html

 

They are also covered in the Particle Adventure link I provided earlier. Quarks are part of the standard model of particle physics.

[Damo2600]

mc^2 = Ec^2 - pc^2

 

No,

 

p = 0

 

mc^2 = Ec^2

 

m = E

 

No,

 

m = 0

 

o = Ec^2 - pc^2

 

E = p

 

Sorry not helping.

 

I think what you are trying to show me is you can use math to blur the subject. I proved a point and you didn't like it.

 

Power corrupts and absolute power corrupts absolutely.

 

Damien

[Damo2600]

Hello Tormod,

 

When did I require others to do research?

 

If you are refering to the particle thing I am correct we don't know what particles are.

 

Qwfwq pointed out that we don't even know what a chair is. Yet he was stating that we know a lot about particles. I didn't see how this was contradictory to my statement. But it appeared to me that he was suggesting that by knowing a lot about particles is some how equivalent to know what a particle was. So I asked him what a particle was.

 

He couldn't answer in a way that suggested he knew what a particle actually was so I guess my original statment remains true. We don't know what a particle actually is.

 

Damien

[Damo2600]

Tormod I think we should stick to the subject which is does energy have mass.

[Tormod]

He couldn't answer in a way that suggested he knew what a particle actually was so I guess my original statment remains true. We don't know what a particle actually is.

 

FYI, science is not conducted by asking one person "what is this" and then evaluating that reply and concluding that no, my opinion is more likely.

[Tormod]

Tormod I think we should stick to the subject which is does energy have mass.

 

So far it seems to me that it has been established that this depends on what one defines as mass, and what kinds of mass one refers to. This thread is a classic example of an endless circular loop.

[Damo2600]

Very nice Tormod,

 

I go out of my way to show that the speed of light via group velocity is invariant, i.e disproving the fact that energy is massless (i.e. with invariant velocity, Energy is also invariant, therefore mass of light is also invariant), and that is the comment you return with, i.e. that it's circular reasoning. I'm sorry Tormod but I'm sure I'm not the only one who will have something to say about that....

 

Damien