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View Full Version : Two Simplistic Questions to Tear Apart!



AonSao
2008-Dec-31, 09:07 AM
1. Because of an equation derived from E=MC^2 we believe that nothing can travel faster than the speed of light. But doesn't the original equation basically say that mass can only become energy after it reaches the speed of light squared?

2. First, two statements. The speed of light changes based on the medium it is traveling through. I hold the belief that since space can be contracted it must be tangible in some way. So.... is it possible that the 'fabric' of space also slows down the speed of light? Could the real speed of light be much faster? I want this to be true for the sake of space-travel! hehe

alainprice
2008-Dec-31, 02:32 PM
You need to start with the axiom itself:
-the speed of light, in a vacuum, is the same for all observers. Like you're saying, we don't care what the actual number is, only that it is constant.

From this, we then find that E=mc2 for the rest mass of a particle.

From this axiom, we find that distance is not absolute. So an image that appears to have travelled 10 miles for you might have had to travel 5 miles for me, even though we are seeing the same 'moment in time'. The image i see will be blueshifted.

Your ideas do not pan out. However, you touched on one more thing. The speed of light itself.

We define it as a constant in empty and flat space. If you can find space that's more empty than empty, then who knows what'll happen.

swansont
2008-Dec-31, 02:39 PM
1. Because of an equation derived from E=MC^2 we believe that nothing can travel faster than the speed of light. But doesn't the original equation basically say that mass can only become energy after it reaches the speed of light squared?

No, that's not what the equation implies.

What it says is that mass is a form of energy. And we also know that it can be converted into other forms. One such possible conversion is into photons, and photons travel at the speed of light.




2. First, two statements. The speed of light changes based on the medium it is traveling through. I hold the belief that since space can be contracted it must be tangible in some way. So.... is it possible that the 'fabric' of space also slows down the speed of light? Could the real speed of light be much faster? I want this to be true for the sake of space-travel! hehe

The specified value for c is in a vacuum. In virtually all circumstances, changes to the vacuum will reduce the speed of light. (One possible exception is the vacuum modification from the Casimir effect, but this is too small to test with current techniques)

trinitree88
2009-Jan-02, 05:02 PM
You need to start with the axiom itself:
-the speed of light, in a vacuum, is the same for all observers. Like you're saying, we don't care what the actual number is, only that it is constant.

From this, we then find that E=mc2 for the rest mass of a particle.

From this axiom, we find that distance is not absolute. So an image that appears to have travelled 10 miles for you might have had to travel 5 miles for me, even though we are seeing the same 'moment in time'. The image i see will be blueshifted.

Your ideas do not pan out. However, you touched on one more thing. The speed of light itself.

We define it as a constant in empty and flat space. If you can find space that's more empty than empty, then who knows what'll happen.

alain. Actually, maybe there's money to be made here....we could be selling emptiness credits for those who keep wanting to gunk up their spacetime with all this mythical stuff, like Baby Ruth bars, and the "emptyier" our space is...the more it's worth big bucks...:shifty::lol: pete

alainprice
2009-Jan-02, 05:13 PM
I'd like to stake my claim on the nearest galactic void.

Watch out Casimir, I'm coming for you!