[Thane_Banquo]

The speed of light has never been constant. It is only constant in a vacuum, or a piece of glass, or a quartz crystal (that is to say, light will always travel the same speed in a piece of glass, or in a quartz crystal, or in a vacuum, but if it goes from one medium to another, its speed will change). If light travels through interstellar clouds, it will of course slow down.

[The Electrician]

Davies, and astrophysicists Tamara Davis and Charles Lineweaver from the University of New South Wales published the proposal in the August 8 edition of scientific journal Nature.

Wow... Looks like not only have they debunked Einstein, but they have also achieved time travel, having journeyed into the future to publish their findings.

[Darth Reagan]

bump

[onedoug]

Hmm.

I'll aways recall Davies" last words in his The Mind Of God:

"We were meant to be here."

[RoughDobermann]

I have a question. Is it not true that E=MC2 states that as an object with mass approaches the speed of light, its mass will increase to the point that it cannot accelerate further and never achieve "light speed"? If so, then how does light travel at the speed of light? Light has mass, doesn't it? If not, why is it effected by gravity?

Please forgive the question, but I have zero background in such matters. It just seems like a logical question...

[Cagey]

[VadeRetro]

The suggestion that the speed of light can change is based on data collected by UNSW astronomer John Webb, who posed a conundrum when he found that light from a distant quasar, a star-like object, had absorbed the wrong type of photons from interstellar clouds on its 12 billion year journey to earth.

The writing--I assume the reporter is a fault--obscures the message. Light does not absorb photons. Interstellar gas and dust absorb photons. Something like that seems intended.

They also applied another dogma of physics, the second law of thermodynamics, which Davies summarizes as "you can't get something for nothing."

That would be the first law. The second law is that entropy always increases in a closed system. ("You can't break even.")

What really bugs me is that the fans of Australian creationist Barry Setterfield (Mr. CDK) will be all over this thread claiming vindication. I see two possibilities. 1) This theory does not vindicate CDK. 2) This theory is a crock.

[SunkenCiv]

From 2002.

[SunkenCiv]

Note: this topic was posted in August of 2002, nearly five years ago.

Paul Davis is a big shot in string theory.