By Michael Christie
Reuters

SYDNEY (Aug. 7) - A team of Australian scientists has proposed that the speed of light may not be a constant, a revolutionary idea that could unseat one of the most cherished laws of modern physics -- Einstein's theory of relativity.

The team, led by theoretical physicist Paul Davies of Sydney's Macquarie University, say it is possible that the speed of light has slowed over billions of years.

If so, physicists will have to rethink many of their basic ideas about the laws of the universe.

''That means giving up the theory of relativity and E-mc squared and all that sort of stuff,'' Davies told Reuters.

''But of course it doesn't mean we just throw the books in the bin, because it's in the nature of scientific revolution that the old theories become incorporated in the new ones.''

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.

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.

Davies said fundamentally Webb's observations meant that the structure of atoms emitting quasar light was slightly but ever so significantly different to the structure of atoms in humans.

The discrepancy could only be explained if either the electron charge, or the speed of light, had changed.

IN TROUBLE EITHER WAY

''But two of the cherished laws of the universe are the law that electron charge shall not change and that the speed of light shall not change, so whichever way you look at it we're in trouble,'' Davies said.

To establish which of the two constants might not be that constant after all, Davies' team resorted to the study of black holes, mysterious astronomical bodies that suck in stars and other galactic features.

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

After considering that a change in the electron charge over time would violate the sacrosanct second law of thermodynamics, they concluded that the only option was to challenge the constancy of the speed of light.

More study of quasar light is needed in order to validate Webb's observations, and to back up the proposal that light speed may vary, a theory Davies stresses represents only the first chink in the armor of the theory of relativity.

In the meantime, the implications are as unclear as the unexplored depths of the universe themselves.

''When one of the cornerstones of physics collapses, it's not obvious what you hang onto and what you discard,'' Davies said.

''If what we're seeing is the beginnings of a paradigm shift in physics like what happened 100 years ago with the theory of relativity and quantum theory, it is very hard to know what sort of reasoning to bring to bear.''

It could be that the possible change in light speed will only matter in the study of the large scale structure of the universe, its origins and evolution.

For example, varying light speed could explain why two distant and causally unconnected parts of the universe can be so similar even if, according to conventional thought, there has not been enough time for light or other forces to pass between them.

It may only matter when scientists are studying effects over billions of years or billions of light years.

Or there may be startling implications that could change not only the way cosmologists view the universe but also its potential for human exploitation.

''For example there's a cherished law that says nothing can go faster than light and that follows from the theory of relativity,'' Davies said. The accepted speed of light is 300,000 km or 186,300 miles per second.

''Maybe it's possible to get around that restriction, in which case it would enthrall Star Trek fans because at the moment even at the speed of light it would take 100,000 years to cross the galaxy. It's a bit of a bore really and if the speed of light limit could go, then who knows? All bets are off,'' Davies said.

einstein was wrong!

Ive already posted something about this but who cares...

I think that einstein was right and always will be.

I dont think einstein was right, and I dont think these guys are either. We'll never know ANYTHING for sure..we can never be absolutly positive... I think Einstein had the right idea..and I think these guys are on the right track too...but we can never be positive about anything...

[This message has been edited by runaway (edited 08-09-2002).]

i'm happy with the current speed of light... i never have to wait more than .00000000001 seconds from the time i flip the switch to the moment i can see my way to the pisser at 4am.

Here's and idea for those who understand such things.

Time slows down in a gravity well. All current measurements have been made in the triple gravity well of the galaxy, the solar system, and Earth.

In intergalactic space without a gravity well to compress space, light should be able to travel faster, at it's true maximum speed.

Just a thought.

i was only kidding about einstein, but they do have a good argument.

interesting theory as well, prometheus.

"Call the men of science, and sing to them this song. Tell them Albert Einstein and Copernicus were wrong!"

Now it's been known for quite some time that the speed of light changes through different mediums. I wouldn't be surprised at all if this guy's quasar photons were a little lazier than normal after passing through a couple billion light years of space, nebulae, and free hydrogen...

That's not to say, though, that things can't change. If you think about electrons orbiting their nuclei for ages upon ages, what happens when they get old and slow down? It could be just another factor indicating the slow and steady march towards the energy death of the universe.

~Zero the Inestimable

I think it was David Blaine once said.

"The fact is that the wings help the plane fly because of the force of the speed pushing them hence flying - but what if that fact is just a theory ? There if thought hard enough could be a more logical answer to it. Just because it seems the more logical doesnt mean its the correct answer"

All im saying Einstiens theory could seem correct but it could be utterley wrong just like these researchers. I am sceptic when it comes to any kind of science.

Peace Renegade,

That's a good stance. Either way it turns out, somehow I don't see it affecting our lives anytime soon.

Who knows?

Everything is relative. Speed is relative. Time is relative. Meters and seconds are defined by fallible men. There is no perfect frame of reference, no perfect observation. Everything relies upon the perceptions of the observer.

I'd care about the real world, 'cept I've never actually seen it...

first off, these guys should know that quasars and black holes are the same thing.

the difference is quasars(quasi-stellar radiation source) were discoverd first, black holes were only theories at the time.

only when it was discovered that black holes would also emit radiation that the link between the two was established.

i don't have a web site for the link that supports this but you can view it stephen hawkings universe, of which this part i watched just last night.
http://video.barnesandnoble.com/search/product.asp?userid=53GG1CQ2ZN&EAN=794054567533

they should have also known that the speed of light is not constant, it is only constant to two observers in different positions and distances measuring the source.

gravity, water, windows all slow down the speed of light by bending it.

they should also have known that the speed of light is not the constant in einsteins equation, but that change is.

einsteins equation ended the steady state theory of the universe when edwin hubble showed the universe expanding proving einsteins theory that the universe is in a constant state of change.

quote:

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Originally posted by ThetaReactor:
Meters and seconds are defined by fallible men.

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Seconds are defined by the pulse of the Cesium 33 atom.