Speed of light may not be constant, physicists say (Whoops)

Fox Live Science ^ | 4-29-2013 | Jesse Emspak

[equalator]

The speed of light is constant, or so textbooks say. But some scientists are exploring the possibility that this cosmic speed limit changes, a consequence of the nature of the vacuum of space.

The definition of the speed of light has some broader implications for fields such as cosmology and astronomy, which assume a stable velocity for light over time. For instance, the speed of light comes up when measuring the fine structure constant (alpha), which defines the strength of the electromagnetic force. And a varying light speed would change the strengths of molecular bonds and the density of nuclear

[dr_lew]

Refraction, like in a prism, is due to light slowing down in speed as it enters the prism medium.

Yes but in matter, light propagates as a "dressed" particle. That is, it is repeatedly absorbed and re-emitted by interactions with the electrons in the medium, and it is the propagagation of this complex interaction that has the lower speed.

This is analogous to the theory of the Higgs boson imparting mass to the various elementary particles by "dressing" them with its interactions, AFAIUI.

[Yellowstone Joe]

Which begs the question. Is the universe really as d as we have been told?

[Yellowstone Joe]

Which begs the question. Is the universe really as old as we have been told?

[Tau Food]

Is the universe really as old as we have been told?

If my memory is accurate, it is older than I am. More I cannot say. ;-)

[The Cajun]

Still think there are certain regions in space, not talking about in the vicinity of a large gravitational field (Blackhole), where
space/time and therefore the speed of light, get *screwy* compared to the physics in the reference frame we occupy.

[CharlesWayneCT]

Yes. And the “speed of light” is defined as “the speed of light in a vacuum”.

And now this paper is saying that there are different kinds of vacuum.

[Boogieman]

Slowing photons down is easy, all you have to do is send them through a medium. Are they slowing them down in a vacuum?

[Boogieman]

I don’t think that they will find that light has mass. It makes intuitive sense that they can’t both have mass and travel at the speed of light. At that speed, length contraction will cause them to become 2 dimensional, and I can’t conceive that a 2 dimensional object can have mass which would effect 3 dimensional objects. So, just a hunch, I doubt they have any mass, and if they did, they’d become something other than a photon, and travel slower than c.

[Boogieman]

Well, these guys aren’t theorizing that the universal light speed can change or decay, they’re just talking about the local light speed. Essentially, they’re saying the vacuum isn’t just a vacuum, because it’s full of virtual particles, so there is a local light speed in every region of space.

Though, if they are correct, and if something caused the density of the vacuum particles to vary over time, then that could have implications essentially the same as if the universal speed of light varied.

[Pikachu_Dad]

Well, are they then the ‘missing mass’ being looked for.

[cynwoody]

GO NAVY!

LCDR Albert Michelson, in 1918

[ctdonath2]

Makes a lot of sense, solves a lot of problems.
And now seems we don’t know much about nothing...er...vacuums.

[JCBreckenridge]

I’ve always thought that gravity has a x*3 term which is repulsive. In most normal scales, it has no function. On the galactic and intergalactic scales it can come to dominate the x*2 term which we are more familiar.

[wardaddy]

So when I tell my boys

186,000 miles per second

I’m a liar!

Man those Max Planck folks are into everything....how many fields of science are they in to?

I looked it up....80....and old Max while not a Christian at least believed in God

Unlike most smart big forehead sorts today

Light.....DNA....

[silverleaf]

“CAUTION: Light Brakes for Ephemeral Virtual Unstable Elementary Particles”

[USNBandit]

Albert Michelson, the guy who determined the speed of light. He won the Nobel prize and was a graduate of Annapolis.

[sopwith]

http://www.youtube.com/watch?v=M3K86Vge0Gc
Chuck Missler study in genesis goes into the whole light speed thing , mostly in the 2nd session . Quite interesting

[Las Vegas Dave]

Bookmark for later read..

[TheZMan]

“length contraction will cause them to become 2 dimensional”

And I can’t conceive that ever making any sense.

[BrandtMichaels]

Couple this with gravitational time dilation [per one Albert Einstein] and then the long ages for the Earth and Universe become much more ‘apparent’...

101 Evidences for a Young Age of the Earth...And the Universe
http://creation.com/age-of-the-earth

See also:

Starlight and Time by Russell Humpheys
The key to the starlight and age of the universe is ‘gravitational time dilation’.