Try cotton balls. I guess they're not matter?

How about salt?

e and m fields are made of virtual photons, OK.

But I'm also told that light is made out of mutually-inducing e and m fields! So says Maxwell's equasions.

Isn't that going in circles?

I hadn't heard that the speed of light had been measured transverse to the plates of the casimir chamber. I read that it would be very difficult to do so, but that was some time ago. Do you have a link?

The Casimir effect was quantitatively verified in 1996 by Lamoreaux to high precision. It follows according to QED (Feynman) and calulations by Scharnhorst that the speed of light must be affected by the reduction in zero point energy. Another paper here.

I am not sure if anyone has experimentally verified the increase in C as yet but I seem to recall that it has been done. The effect was tiny, something like 10^-12 or some such. But it's not how well the bear dances, it's that he dances at all.

That tiny volume of space between the Casimir plates is depleted in energy; in other words it has a lower energy than the ordinary vacuum...
I don't find it surprising that the speed of light is faster in such a volume of space- the problem is trying to use that effect.

I still think wormholes (which also use negative values of energy) offer a better prospect than faster than light drives.

But I am not going to hold my breath...

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New Orion's Arm Site . The Starlark . Against a Diamond Sky (OA Novella Collection) . OA Flickr set

Yes, thank you all for very interesting posts and including the diversions into Casimir force, etc.

The teacher has recanted. Her source was not some state educational materials thank goodness (it was the internet! no surprise. madscinet to be precise). She said she told the class that light was not matter.

Then this past week my son took some science test, state mandated, in which the question came up (identify the item that is not matter. Among four choices was light). The correct answer in the test was that light is not matter.

So I am relieved.

Learned a lot about light the past few weeks!

Boris

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"science is where culture rubs against nature" - Stanislaw Lem, His Master's Voice

That's great to hear! Thanks for the update.

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Old laser physicists never die, they just become incoherent.
These days, every Tom, Dick, and Harry thinks he knows what a photon is, but he is wrong. - Albert Einstein

Light i not matter, because the definition of matter is:

´´Matter is everything that weighs and occupies a place``

You cannot touch or weigh light, there for it is not matter, light is an electromagnetic radiation of a wavelenght that is visible to the human eye!

I hope i helped the problem

Just over five years!!!

Is this a new record for thread necromancy?

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If I set the budget, we'd have Ares and more. Unfortunately, I don't set the budget, and Ares is just too expensive and too far out for us to accomplish our goals within the budget we were given.

If we halt the ISS, all versions of Ares, and transport Orion and Altair aboard DIRECTv3's Jupiter family of Shuttle-Derived Launch Vehicles, we just might make it back to the Moon by 2020.

And the debate rages on! Seriously, i though it's the opposite, that matter is a nice misconception useful when dealing with macroscopic world.

I think what you meant was that photons mediate the electromagnetic force.

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I would say that energy is something apart from matter. There is no such thing as energy particles. Bosons (eg: photons) are matter just like fermions (the quarks that make up protons for instance or leptons like electrons).

Energy, on the other hand, is that which causes change (or prevents it in the face of competing forces). Like ionizing radiation causing an emission nebula to glow. The photons emitted by the local star have energy, but I wouldn't say that they are energy.

I could see how one would be tempted to call everything energy, because every thing possesses energy; however, it seems to me important to make room the subtle difference between having energy and being energy.




M74

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I pray to no one.