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| Dagg |
 Posted: Wed Feb 13, 2008 6:04 pm Post subject: The speed of light |
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Just wondering, How do we know that the spped of light is the fastest? It could be that light is the fastest speed that we know of, but not somewhere else in the universe.
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weeehoo! |
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| teeniewitabeenie1 |
| Posted: Wed Feb 13, 2008 9:19 pm Post subject: |
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Location: making lemons into lemonade
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we know nothing for certain, its all just theories.........
and because Einsten said so but years from now Einstein will probly be proven wrong like Newton was......
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| harryschneider |
| Posted: Thu Feb 14, 2008 5:20 am Post subject: Re: The speed of light |
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| Dagg wrote: |
| Just wondering, How do we know that the speed of light is the fastest? It could be that light is the fastest speed that we know of, but not somewhere else in the universe. |
I think Einstein is may be right on this one. BUT might a light beam approaching a black hole speed up? Does anyone know of any experimental observation?
Whilst the LIGHT from an object may have a limited speed the object itself could be travelling faster that its light. (Hence the blue shift of the Doppler effect)
A jet plane can travel faster than it's sound so why can't an object travel faster than it's light?
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Harry Schneider |
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| Ophiolite |
| Posted: Thu Feb 14, 2008 5:58 am Post subject: Re: The speed of light |
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Forum Radioactive Isotope
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| harryschneider wrote: |
| A jet plane can travel faster than it's sound so why can't an object travel faster than it's light? |
Because that is the way the laws of the Universe operate. As the object moves ever faster its mass increases, requiring even more energy to accelerate this. It can only approach the speed of light asymptotically: it would never quite reach it, even if you were to supply the energy. In consequence it is certainly not going to travel faster than light.
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| GrowlingDog |
| Posted: Thu Feb 14, 2008 6:06 am Post subject: Re: The speed of light |
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Joined: 09 Feb 2008
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I think Einstein is may be right on this one. BUT might a light beam approaching a black hole speed up? Does anyone know of any experimental observation?
Thats' a curious question and i have no idea of the answer. I mean a black hole's gravity can prevent light escaping but can it draw it in faster than it is already travelling? If anyone does have an answer, i'd love to hear it.
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Life is 10% what happens to you and 90% how you react to it. |
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| KALSTER |
| Posted: Thu Feb 14, 2008 6:19 am Post subject: Re: The speed of light |
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Forum Professor
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| GrowlingDog wrote: |
I think Einstein is may be right on this one. BUT might a light beam approaching a black hole speed up? Does anyone know of any experimental observation?
Thats' a curious question and i have no idea of the answer. I mean a black hole's gravity can prevent light escaping but can it draw it in faster than it is already travelling? If anyone does have an answer, i'd love to hear it. |
It can only blue-shift. It is still traveling at the same speed though, and always will.
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"Gullibility kills" - Carl Sagan |
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| harryschneider |
| Posted: Thu Feb 14, 2008 6:57 am Post subject: Re: The speed of light |
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[quote="Ophiolite"]Because that is the way the laws of the Universe operate.[quote]
Yes I understand the theory but I am still uneasy at accepting blindly the implications just because Einstein said so. There is still a possibility that there are some unseen/unknown factors which should yet be taken into account. What they could be - I have no idea!
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Harry Schneider |
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| GrowlingDog |
| Posted: Thu Feb 14, 2008 6:38 pm Post subject: Re: The speed of light |
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| KALSTER wrote: |
| GrowlingDog wrote: |
I think Einstein is may be right on this one. BUT might a light beam approaching a black hole speed up? Does anyone know of any experimental observation?
Thats' a curious question and i have no idea of the answer. I mean a black hole's gravity can prevent light escaping but can it draw it in faster than it is already travelling? If anyone does have an answer, i'd love to hear it. |
It can only blue-shift. It is still traveling at the same speed though, and always will. |
So, while a star can speed up say, a comet as it gets closer to it and stop it completely if the comet hits the sun, all from the effects of gravity, light cannot be drawn in faster, no matter how strong the gravity? Also, if a black hole can stop or trap a beam of light, can something with a gravitational effect a little less than a black hole slow a beam of light down a lot? I feel and probably sound like a 5th grader, i'm sorry.
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Life is 10% what happens to you and 90% how you react to it. |
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| Cynapse |
| Posted: Fri Feb 15, 2008 7:40 am Post subject: Re: The speed of light |
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Joined: 14 Feb 2008
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| GrowlingDog wrote: |
| KALSTER wrote: |
| GrowlingDog wrote: |
I think Einstein is may be right on this one. BUT might a light beam approaching a black hole speed up? Does anyone know of any experimental observation?
Thats' a curious question and i have no idea of the answer. I mean a black hole's gravity can prevent light escaping but can it draw it in faster than it is already travelling? If anyone does have an answer, i'd love to hear it. |
It can only blue-shift. It is still traveling at the same speed though, and always will. |
So, while a star can speed up say, a comet as it gets closer to it and stop it completely if the comet hits the sun, all from the effects of gravity, light cannot be drawn in faster, no matter how strong the gravity? Also, if a black hole can stop or trap a beam of light, can something with a gravitational effect a little less than a black hole slow a beam of light down a lot? I feel and probably sound like a 5th grader, i'm sorry. |
The thing you have to ask is the light speeding up relative to who? If light is travelling at c relative to us it can't speed up because time slows down. It may be convering a greater distance relative to us but the time slowing it takes relative to us near a black hole means the light is still going at c. |
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| (Q) |
| Posted: Fri Feb 15, 2008 7:59 am Post subject: Re: The speed of light |
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Forum Ph.D.
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| GrowlingDog wrote: |
So, while a star can speed up say, a comet as it gets closer to it and stop it completely if the comet hits the sun, all from the effects of gravity, light cannot be drawn in faster, no matter how strong the gravity? |
Light does not slow down or speed up, it merely loses or gains energy. So, if light is being drawn towards a gravity well, it will increase in energy, and blueshift. If it manages to climb out of the gravity well, it will decrease in energy and move towards the red spectrum.
Light will continue to travel at c as it's speed depends entirely on the properties of space: permittivity (electric) and permeability (magnetic).
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I may have no understanding of the current theory of evolution. But that's because science keeps changing it. A few weeks ago I read in the newspaper that it had once again been adjusted & just the other day I discovered a new book called "The New Theory of Evolution" ~~Steven Titchenell : W.V.B.I.G. President. |
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| KALSTER |
| Posted: Fri Feb 15, 2008 9:19 am Post subject: |
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Joined: 08 Sep 2007
Posts: 1487
Location: South Africa
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| Quote: |
| So, while a star can speed up say, a comet as it gets closer to it and stop it completely if the comet hits the sun, all from the effects of gravity, light cannot be drawn in faster, no matter how strong the gravity? Also, if a black hole can stop or trap a beam of light, can something with a gravitational effect a little less than a black hole slow a beam of light down a lot? I feel and probably sound like a 5th grader, i'm sorry. |
When light is "sucked" into a black hole, it does so because of the curvature of space-time (gravity). So all the light does is follow the path of the curvature. The same happens inside a black hole, where space is curved to such a degree that light can't advance beyond the event horizon.
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| GrowlingDog |
| Posted: Fri Feb 15, 2008 5:30 pm Post subject: |
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| KALSTER wrote: |
| Quote: |
| So, while a star can speed up say, a comet as it gets closer to it and stop it completely if the comet hits the sun, all from the effects of gravity, light cannot be drawn in faster, no matter how strong the gravity? Also, if a black hole can stop or trap a beam of light, can something with a gravitational effect a little less than a black hole slow a beam of light down a lot? I feel and probably sound like a 5th grader, i'm sorry. |
When light is "sucked" into a black hole, it does so because of the curvature of space-time (gravity). So all the light does is follow the path of the curvature. The same happens inside a black hole, where space is curved to such a degree that light can't advance beyond the event horizon. |
Cool! thank you Kalster. Learning, ever learning.
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Life is 10% what happens to you and 90% how you react to it. |
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| Ophiolite |
| Posted: Fri Feb 15, 2008 5:31 pm Post subject: Re: The speed of light |
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Forum Radioactive Isotope
Joined: 25 Jul 2005
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[quote="harryschneider"][quote="Ophiolite"]Because that is the way the laws of the Universe operate.
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| Yes I understand the theory but I am still uneasy at accepting blindly the implications just because Einstein said so. |
I think the issue is that it is not just because Einstein said so, but because many studies of phenomena, based upon observation, experimentation and theoretical investigations, confirm the validity of the idea. As you note, something different may turn up. That is why the conclusions of science are provisional. However, at this point there seems an infinitesimally small likelihood of such being the case.
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The Universe is not only weirder than we imagine it is weirder than we can imagine. J.B.S.Haldane. |
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| zizzy34 |
| Posted: Sun Feb 17, 2008 12:37 pm Post subject: |
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| musicalaviator |
| Posted: Sat Feb 23, 2008 1:01 am Post subject: |
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| The unchangability of the speed of light is more than just theory. It's the main idea behind accurate clocks on moving vehicles (sattelites particularly) and as a result, the only reason that GPS systems work without needing to have radio transmitters on the ground every few hundred miles. |
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