Posted on 08/08/2002 9:06:23 AM PDT by Momaw Nadon
SYDNEY (Reuters) - 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 (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.
Could be. I don't like posting duplicate threads, which is why I usually search before posting. It would be helpful if the search turned up articles that may have been posted to "other" forums such as General Interest. (or moved there by the Admin Mods). It would save some effort for those who are trying to search first, as well as for the Admin Mods who are trying to keep up with those who don't.
I think it goes even deeper than that. The speed of light is assumed to be constant on the basis that any observer anywhere who measures electrical and magnetic properties of a vacuum will get the same numbers. E.g., the electric field due to a unit of electrical charge is the same here as it is halfway across the universe.
If those properties can change from place to place, then the speed of light can likewise change, and an observer can detect his motion through a vacuum by monitoring its value. Who's to say they don't change?
40 years ago when I got my degree in physics I asked those kinds of questions of my professors. They pointed out that there was an opportunity for me to make my mark in physics if I could answer those questions myself. Well, I didn't have the horsepower then, and got my degree anyway. But I still wonder.
It would help if you understood the difference between Biblical Creationism and Scientific Creationism. Scientifically you can't prove that God created the world in six days, or fish on the 5th day, or that there was a man named Noah. That's Biblical and you either accept it by faith or you don't.
Creation Science deals with the age of the earth and universe, fixity of species, catastrophic geology (vs. uniformatiarianism), etc. These are things that science deals with and I believe the evidence supports a recent creation and a global flood, and contradicts evolution. Just like Newton and Pastuer and thousands of other creation scientists have believed.
Far Sider's objection is that in a young universe the light would have to be created already on its way to earth at all points between earth and the distant source. No problem with that so far, but, it means that some observers in the universe will have sharp disagreements about the order of events in various places. I.e., cause and effect get to be ambiguous, and, I suppose, free will goes out the window.
I tried it and I was about to correct you, but then I realized the batteries in my watch were dead.
Fair enough. But how come you get to pick and choose which sections of Genesis to take literally, and which to take metaphorically? Why is it so hard to understand God creating the earth in seven days, as being a metaphor for the multi-billion-year creation process since the Big Bang?
By means of disclosure, I think the Bible is bunk, but have no problem with others believing in it.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.