boxhead Posted February 4, 2005 Posted February 4, 2005 einstein took speed of light constant and accordingly varied other parameters like space-time, but can we take someother parameter as a constant insted of speed of light. e.g. space or time and can prove the theory of relativity. because light can also bend in space-time.
5614 Posted February 4, 2005 Posted February 4, 2005 because light can also bend in space-time. light doesn't travel in a straight line (read on!) instead it takes the shortest distance between 2 points. normally this distance is a straight line, however when (or if) space-time bends, light will bend with it.... this is not "breaking relativety" its 'normal' light behaviour.
swansont Posted February 4, 2005 Posted February 4, 2005 einstein took speed of light constant and accordingly varied other parameters like space-time, but can we take someother parameter as a constant insted of speed of light. e.g. space or time and can prove the theory of relativity. because light can also bend in space-time. Einstein did so for a reason, not on a whim. In Electrodynamics, c must be a constant in all frames in order for the wave equation to hold. Since we know that EM waves continue to be waves when the source or observer is moving (i.e. you can still see, and your radio works, when your are travelling in your car) it seems to be valid. What Einstein did was to apply this to "mechanical" systems as well.
boxhead Posted February 4, 2005 Author Posted February 4, 2005 Einstein did so for a reason, not on a whim. In Electrodynamics, c must be a constant in all frames in order for the wave equation to hold. Since we know that EM waves continue to be waves when the source or observer is moving (i.e. you can still see, and your radio works, when your are travelling in your car) it seems to be valid. What Einstein did was to apply this to "mechanical" systems as well. accordingly we can also redfine the electrodynamics theory. no parameter is constantly constant.
[Tycho?] Posted February 4, 2005 Posted February 4, 2005 accordingly we can also redfine the electrodynamics theory. no parameter is constantly constant. The speed of light is measured to be constant, which is why this came up. If you varied something else you would get c as a non constant, which doesn't happen in our experience.
umer007 Posted February 6, 2005 Posted February 6, 2005 light doesn't travel in a straight line (read on!) instead it takes the shortest distance between 2 points. normally this distance is a straight line' date=' however when (or if) space-time bends, light will bend with it.... this is not "breaking relativety" its 'normal' light behaviour.[/quote'] would it be considered infront of black or white hole light bends because space-time bend also? is there anyother way of space-time bending?
swansont Posted February 7, 2005 Posted February 7, 2005 accordingly we can also redfine the electrodynamics theory. no parameter is constantly constant. Be my guest. I await your version of Maxwell's equations.
kotake Posted February 12, 2005 Posted February 12, 2005 '']The speed of light is measured to be constant, which is why this came up. If you varied something else you would get c as a non constant, which doesn't happen in our experience.Some experiments indicate that the speed of light is not constant. I recently read that accordring to the physicist João Magueijo, the speed of light was several trillions that of c in the moment of Big Bang, and has drastically been decreasing for some 10 billion years. Some two billion years ago, it has slowly been increasing again.
mezarashi Posted February 14, 2005 Posted February 14, 2005 It may be true, but you're going to have to come up with a theory to say that the laws of physics actually changes over time. I think its not too farfetched a theory, as there has been some indication that the physics of very very distant galaxies may be different from we know in our locale. However, as we know it on Earth, and for all practical reasons, the speed of light is constant, and as long as that is the case given any reference locale, then there won't be a problem.
swansont Posted February 14, 2005 Posted February 14, 2005 Some experiments indicate that the speed of light is not constant. I recently read that accordring to the physicist João Magueijo, the speed of light was several trillions that of c in the moment of Big Bang, and has drastically been decreasing for some 10 billion years. Some two billion years ago, it has slowly been increasing again. References, please, for the latter part. Some experiments investigating the fine structure constant, which includes c, have shown limited (a part in 105) change over the period you state, and others are consistent with zero change, so this may just be an upper bound, limited by experimental error.
kotake Posted February 17, 2005 Posted February 17, 2005 References' date=' please, for the latter part. Some experiments investigating the fine structure constant, which includes c, have shown limited (a part in 10[sup']5[/sup]) change over the period you state, and others are consistent with zero change, so this may just be an upper bound, limited by experimental error. I read it in a magazine (Illustrert Vitenskap nr 4, 2005). But here is this book, "Faster Than the Speed of Light" written by Magueijo, and besides, if scroll down a little (to section ten), there is a paragraph or two about it on this page.
blike Posted February 18, 2005 Posted February 18, 2005 As a former professor of physics, I am greatly concerned that this book will be viewed by non-physicists as being on par with some of the excellent "pedestrian" books on advanced physics, such as "A Brief History of Time" or "The Elegant Universe". Mr. Magueijo's attempts to explain elementary electrodynamics and mechanics show that his mastery of physics would not even earn him a passing grade in one of my freshman-level courses. I would not be at all surprised if Cambridge contacted Mr. Magueijo and demanded that he return his diploma. As a trained and working mathematician and physicist, I would consider this book good to have around...for when I was in need of a laugh. The hardcover version, I am sure, is well suited for use as a paperweight. And most certainly, a person freezing to death would find warmth and light by setting the book afire. Beyond those uses, this book cannot be considered anything other than a waste of paper and ink. heh.
swansont Posted February 18, 2005 Posted February 18, 2005 I read it in a magazine (Illustrert Vitenskap nr 4, 2005). But here is this book, "Faster Than the Speed of Light" written by Magueijo, and besides, if scroll down a little (to section ten), there is a paragraph or two about it on this page[/url']. Anybody can write a book, and the London Sunday Times isn't peer-reviewed. Journalists often get stuff wrong, and can't usually evaluate the merits of a scientific argument. This guy apparently has an explanation for a few things in cosmology. But it has ramifications throughout science. If he's right, he has to explain how a varying c fits in with all of physics, not just his little corner of it. Just because an internet site says something, doesn't make it true.
reverse Posted February 18, 2005 Posted February 18, 2005 naww that wouldn’t work at all. you cant build a brick from houses, you must build a house from bricks. (hope you get what I mean).
swansont Posted February 18, 2005 Posted February 18, 2005 (hope you get what I mean). Kinda hard to tell who "you" is, since you didn't indicate to whom you were replying.
kotake Posted February 18, 2005 Posted February 18, 2005 Anybody can write a book' date=' and the London Sunday Times isn't peer-reviewed. Journalists often get stuff wrong, and can't usually evaluate the merits of a scientific argument. This guy apparently has an explanation for a few things in cosmology. But it has ramifications throughout science. If he's right, he has to explain how a varying c fits in with all of physics, not just his little corner of it. Just because an internet site says something, doesn't make it true.[/quote']I see. In which parts of physics does this theory not fit into?
reverse Posted February 19, 2005 Posted February 19, 2005 Kinda hard to tell who "you" is, since you didn't indicate to whom you were replying. oh yea sorry. Boxhead #1
swansont Posted February 19, 2005 Posted February 19, 2005 I see. In which parts of physics does this theory not fit into? All the rest of physics that works just fine with c being constant, and would actually fail if it weren't.
boxhead Posted February 20, 2005 Author Posted February 20, 2005 Be my guest. I await your version of Maxwell's equations. oh sure but you have to wait for few billion years till the laws of physics changes with time.
[Tycho?] Posted February 20, 2005 Posted February 20, 2005 oh sure but you have to wait for few billion years till the laws of physics changes with time. Oh, so the laws of physics change with time. Have a good source for that one?
boxhead Posted February 21, 2005 Author Posted February 21, 2005 '']Oh, so the laws of physics change with time. Have a good source for that one? it is very simple my friend laws of the game dont change and how can you change the laws of physics but one thing is sure that you can improve upon the laws with time to time as we improve the therioes of science for time to time and with time man can improve his own intelligence level and that is done coz of evolution process today what seems impossible is a tomorrows joke.
kotake Posted February 21, 2005 Posted February 21, 2005 All the rest of physics that works just fine with c being constant, and would actually fail if it weren't.Yes, but could you give an example? I may be on the wrong track, but, if c changed throughout time, today's laws of physics would still succeed if we were using them to calculate events that occur at one given moment, that is, if we knew c for that moment.
Cadmus Posted February 21, 2005 Posted February 21, 2005 if c changed throughout time, today's laws of physics would still succeed if we were using them to calculate events that occur at one given moment, that is, if we knew c for that moment. I think that c changes over time. Still, we are all here, arent' we?
swansont Posted February 22, 2005 Posted February 22, 2005 Yes' date=' but could you give an example? I may be on the wrong track, but, if c changed throughout time, today's laws of physics would still succeed if we were using them to calculate events that occur at one given moment, that is, if we knew c for that moment.[/quote'] The strength of atomic and nuclear interactions depend on the value of c. If it changes, it makes chemical and nuclear interactions different. And yet there's plenty of evidence that stars shined in the past, since the light we see is old, and there was a natural reactor on earth 2 billion years ago. It's quite possible that some interactions would start or stop happening if the value of c changed, or the rates would change.
Saint Posted February 22, 2005 Posted February 22, 2005 The strength of atomic and nuclear interactions depend on the value of c. Do they truly depend on the value of c, or do the equations we've developed to model the interactions depend on c? I'm asking because I don't know. But you should realize that there is a difference.
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