| Username |
Post |
| ashu |
Posted
on 14-Feb-03 07:17 PM
Einstein said E= mc square, where c (i.e. speed of light) is constant, right?
But some young physicists are thinking that maybe c is in fact NOT constant
but variable.
Read all about the physicist, who was recently in Boston to promote his heretical ideas, and who likens himself as the "Sex pistols" of physics.
http://chronicle.com/free/v49/i23/23a01401.htm
As Sex pistols belted out, God save the queen, er, in this case, Einstein's theory :-)
oohi
"interested in science in general"
ashu
ktm,nepal
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| DWI |
Posted
on 14-Feb-03 10:13 PM
Thanks for the url Ashu.
I wish we could discuss it too. Speed of light not being constant has been a matter of debate in recent years (none making to Nature Science Journal). The tone in the book is very arrogant but does follow scientific analogies, in the rhythm of Dr Kaku (City College).
One question, if speed of light varied in the beginning what was the cause (may be the book answers). The mass of the entirity couldn't be the factor and time certainly wouldn't have an effect on it, though space-time curve does affect the speed.
Nice posting, hope to see more.
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| noname |
Posted
on 14-Feb-03 10:29 PM
Yeh....I knew from the very begining that speed of light is varying.
Light coming from a Mo-bike comes faster than from a Mountain bike. Axiomatic!
:)
(in jest hai! don't take it otherwise!!)
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| mickthesick |
Posted
on 15-Feb-03 01:53 AM
okay here it goes guys......i'll try my bit of explanation in this topic:
1. scientists do believe that light shows two properties: with mass , and without mass.
a. if light doesn't have mass then it will not be affected by any kinds of attractive forces , for example: gravity. So if light has no mass then it is not affected by gravity and gravitational forces between two heavenly bodies. So it will move with a constant speed.
b. if light has some mass, then it will also be affected by gravity and gravitational forces. for example: it will also be attracted towards the centre of earth by earth's gravity as it happens in our case. we are attracted by earth's gravity so we stay on earth's surface. This means if light coming from space enters earth's atmosphere it will be attracted by earth's gravity and will slow down since it has MASS according to our assumption.
Therefore light might have varying speed.
That's all i have to say for now.
any comment is welcome.
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| DWI |
Posted
on 15-Feb-03 01:42 PM
Michthesick, your theory is a very old but rejected theory. If I am not wrong, it was presented by sir Newton who believed Light bends because it also has mass.
Einstein proposed that even though light doesn't have mass, it does bend in the presence of massive heavenly bodies. Another scientist (Hale something) found a way to prove it via the solar eclipse where light from object behind the sun was seen, thus sending a small bending of light.
Einstein proposed time and space composed a two dimensional entity. Imagine a fabric. If you put a massive ball (Stephen Hawking's analogy) in the fabric, you will see the fabric is pulled in the place where the ball exists. Light has to bend when going through such a surface.
However, this doesn't mean that light has varying speed. Speed = distance/ time. In this equation time is increased but distance is also increased because of the bending, thus Speed remains constant. Thus it is not a good proof for varying nature of speed. There are other postulates, like presented by Ashu's url which suggest that vary nature of light. Read on.
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| czar |
Posted
on 15-Feb-03 05:58 PM
To add to the confusion...
It was reported last year that Fuji Heavy Industries - NEC labs conducted experiments in which they effectively decelerated some photons to 30 mph. In correlating experiments, they were able to accelerate photons to faster than c, the presently accepted value of the speed of light. What is also observed is that the velocity of light can be affected by black holes and super gravity.
Many schools of thought seem to indicate that the presently observable mass of the universe only accounts for about 5% of it hypothetical total mass. What form the remaining 95% assumes forms the battleground for theories and ideas.
That’s where the hypothesis of dark matter and dark energy come in as a proposed explanation. Which dukes it out with string theory, and variants, as another school of thought as a possible explanation of the universe formation and such.
Even making the assumption that the universe is a polyglot of all known theories and a zillion others not yet formulated, what is not known is the full extent of the interaction of light with these as yet undiscovered particles.
Assuming that these unknown materials are the dominant matter that makes up the universe, it is entirely possible that they affect the behavior of light. To what extent and under what circumstances is another riddle that needs solving if the bigger picture is to be complete. Leaving scope for much speculation, which is where Dr. M comes in.
All scientific theories vie for funding and believers. The egos involved are oft as monumental as the equations. That each camp spends considerable energy skirmishing with the opposing schools of thought sometimes leads some to wonder whether they even have time for science.
The key to funding and survival for science and scientists alike is recognition. The present controversy, of course, would be productive if it played well to the gallery. Regardless of his élan, or lack thereof as some would mutter darkly, having a young scientist with sex appeal is a winner for drawing in a wider audience.
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| ? |
Posted
on 15-Feb-03 10:38 PM
Michthesick, your theory is a very old but rejected theory. If I am not wrong, it was presented by sir Newton who believed Light bends because it also has mass.
-->Light has both the qualities of being a particle (photons) and wave.
E=mc^2 (mass) & E=h(nu) (wave)
And debroglie derived:
mc^2=h(nu), exhibiting the particle/wave nature of light or more specifically electromagnetic radiation.
Einstein proposed time and space composed a two dimensional entity. Imagine a fabric. If you put a massive ball (Stephen Hawking's analogy) in the fabric, you will see the fabric is pulled in the place where the ball exists. Light has to bend when going through such a surface.
-->Space and time = 4 dimensions, three spatial dimensions and time is parallel to them.
However, this doesn't mean that light has varying speed. Speed = distance/ time. In this equation time is increased but distance is also increased because of the bending, thus Speed remains constant. Thus it is not a good proof for varying nature of speed. There are other postulates, like presented by Ashu's url which suggest that vary nature of light. Read on.
--> It is nothing novel quite frankly specifically light not being of a constant speed. Yes, it has a threshold of the current 2.99978*10000000 m/s, but still it could exhibit higher speed,however, not exponentially. The exact figure is yet to be established. Remember, uncertainty principle?
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| Adirondack |
Posted
on 15-Feb-03 10:41 PM
Nerds !
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| Adirondack |
Posted
on 15-Feb-03 10:43 PM
oops, i forgot this: :)
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| ? |
Posted
on 15-Feb-03 10:50 PM
Nerds??? I guess, it depends on where your priority lies.
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| Adirondack |
Posted
on 15-Feb-03 10:53 PM
I was just kiddin' yo!
:)
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| DWI |
Posted
on 16-Feb-03 01:01 PM
* By stating that " Light has both the qualities of being a particle (photons) and wave" and presenting plausible equations, if you are trying to say that light has mass then, sorry to say I disagree.
Wave doesn't have mass and Photon has energy and momentum but no mass. For the record, Momentum can exist without mass. We can start a new discussion on this if you want.
* U're right space and time alltogether compose a 4 dimensional surface, but I took the three dimension of the space as one to illustrate the Fabric theory. Got it?
* What has uncertainty principal got to do with the speed of light? One way I understand it is that it is impossible to conclude the position and the speed of a particle at any given instant. Doesn't mean the speed of light varies. Light exhibiting varying speed shouldn't be taken lightly. It actually changes a lot of phenomenon and theorem supported by Physics.
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| Biratnagare |
Posted
on 16-Feb-03 03:27 PM
does anyone have any idea about matter anti matter pairing to explain this duality on the nature of light wave? Einstein postulated the maximum speed of any moving object cannot exceed that of light, not that light has a fixed speed. Every theories are prone to timely verifications as the knowledge bases in the understanding of physical phenonmenon grow up.
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| mirador |
Posted
on 16-Feb-03 03:28 PM
Sorry to be pedantic but isn't the speed of light constant only in vacuum? Light travels at different speeds in different mediums, I think.
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| DWI |
Posted
on 16-Feb-03 03:49 PM
Biratnagare, Einstein didn't come up with the idea of the constant nature of light. But he sure supported it. Anti matter idea was postulated to support the unbalance that exists in universe, recent facts are against this idea more than supporting it. However, as I know, there are few commendable works supporting the anti-matter idea. Do you? I don't.
Mirador, thanks. That was absolutely right. Speed of light varies depending upon the medium. The refractive index of a material is one way of finding the descripancy.
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| noname |
Posted
on 16-Feb-03 05:26 PM
This is not true that Einstein did not notice about the fact that 'c' is varying; however, this occurred to him only late, and he was reluctant to admit it by that time. The story goes like this:
First to understand what actually E = M C square is let me explain it with some analogy as is usually done in the theory of relativity.
E can be explained as total excitation and M as contribution from man and C (SHE) as from woman. What Einstein has to say is: total Excitation is multiplication of excitation of man and woman taken independently but the contribution from SHE is manifold larger than that of contribution from M. A man of his caliber could coin the formula just from his own experience of dealing with his wife. He was a faithful husband and could not conduct the experiment with varying SHE.
And only when he settled in America and was offered a life of NABAB did he realize that SHE, in fact, is variable. He tried some experiments with varying amount of gift from a flower to a car and noticed that there is hell lot of variation in contribution of SHE. But because of his declining age, he could not conclude the contribution of M and/or SHE in the variation. Now these young scientists think that they are the first to know about that variation!
:)
(Btw, I am enjoying the discussion! Don't take it otherwise hai!!)
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| DWI |
Posted
on 16-Feb-03 09:15 PM
I like that noname bro. Humor always helps. We really don't have to be all serious 'bout it.
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| ? |
Posted
on 16-Feb-03 09:45 PM
* By stating that " Light has both the qualities of being a particle (photons) and wave" and presenting plausible equations, if you are trying to say that light has mass then, sorry to say I disagree.
Wave doesn't have mass and Photon has energy and momentum but no mass. For the record, Momentum can exist without mass. We can start a new discussion on this if you want.
--> I was merely pointing out the effects of light under the force of gravity and why?
Mass is a generalized concept which we take for granted, for instance you cannot apply the idea of mass to anti-matter particles.
* What has uncertainty principal got to do with the speed of light? One way I understand it is that it is impossible to conclude the position and the speed of a particle at any given instant. Doesn't mean the speed of light varies. Light exhibiting varying speed shouldn't be taken lightly. It actually changes a lot of phenomenon and theorem supported by Physics.
-->To put it simple, it has a lot to do with the speed of light. Uncertainly principle is the theory that de-establishes THE claim that light has a constant speed, and again I am not taking into account the mathematical errors on our part to calculate it.
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