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Traveling at the speed of light...

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So I was wondering... If you had two people racing in different spaceships, one is going the speed of light, and the other 1mph less than the speed of light, would the one going less than the speed of light look over to the other and see nothing, a beam, or a spaceship "slowly" speeding past?
 





This has actually been determined before. It's called Terrell rotation. The ship moving at the speed of light ( doesn't matter if you're stationary or (c-1mph) would appear elongated as it approached you, and shortened or squashed as it moved away from you.

The best way to describe it absolutely simplistically would be "sort of like doppler shift". (but not quite.)

EDIT 2: meant to edit, not quote. x_x
 
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This has actually been determined before. It's called Terrell rotation. The ship moving at the speed of light ( doesn't matter if you're stationary or (e-1mph) would appear elongated as it approached you, and shortened or squashed as it moved away from you.

The best way to describe it absolutely simplistically would be "sort of like doppler shift". (but not quite.)


dont you mean "c" lol
plus this is in the wrong topic.
or i would be amazed if you came up with an "experiment" in which you could make a spaceship travel at the speed of light, or at c-1mph for that matter


PS: ask a moderator to move it to the "science and lasers" topic. you might get more answers there
 
Basically physics kinda falls apart once we go past the speed of light because there's no tried experiments lol.

Kind of like, if you aimed a telescope at a planet that's so far away, the image of it is delayed, due to the time it takes for light to reach us here on Earth, so what if someone travels there twice the speed of light, then back to Earth, technically he should see him self landing on the planet :p
 
speed of light relative to what? hes only going at 1mph relative to you. I dont think theres any absolute rules that changes your fundamental nature at light speed with respect to everything else, otherwise we'd all be travelling at lightspeed with respect to light and everything would be skewed.
 
speed of light relative to what? hes only going at 1mph relative to you. I dont think theres any absolute rules that changes your fundamental nature at light speed with respect to everything else, otherwise we'd all be travelling at lightspeed with respect to light and everything would be skewed.


if you close your eyes there is no observable light. so your theory is incorrect. light speed is relative to us. we are not relative to light speed. after all light doesn't think or feel.

michael
 
if you close your eyes there is no observable light. so your theory is incorrect. light speed is relative to us. we are not relative to light speed. after all light doesn't think or feel.

michael

i dont think sentience is required to be moving relative to something else.
my point was, if you are moving at lightspeed, you can only be moving at lightspeed relative to something. there is no absolute speed. therefore you are only moving at 1mph relative to something 1mph below lightspeed. also, to say its 1mph below lightspeed means it is taken from the perception of an object you are moving at lightspeed with respect to. however, it is not included in the question, as the point of view is taken from the object travelling at lightspeed to the aforementioned non-existant object. in other words, an absolute speed is implied where there is none.
 
light speed is a fixed value. they are using "c" as an example which is how fast light travels in vaccum.
and things are only relative to us because we can observe. a stick doesnt know its relative size to a tree. we do.

michael.
 
light speed is a fixed value. they are using "c" as an example which is how fast light travels in vaccum.
and things are only relative to us because we can observe. a stick doesnt know its relative size to a tree. we do.

michael.

doesnt need to be aware for it to be true, unless u mean in a deep philisophical way
 
These are enternal mind breakers... but they all boil down to relativity and frame of reference - mostly the latter.

If you were on some spaceship going near the speed of light, and you would shine a flashlight forward, to you, it would appear to operate completely normally, with the beam going away at light speed.

To a stationary observer things would be very different - he'd see a spaceship zooming by with a light beam travelling out of that a at very low relative speed.

With these thought experiments its paramount to consider your frame of reference - are you on the spaceship, on the slightly faster one, or a stationary observer?
 
The only answer to this question is, Einstein's 2nd postulate. "The speed of light is the same in every inertial frame of reference." Look it up.
Light moves at 'the speed of light' ALWAYS. In EVERY situation.
Einstein wrote a book, "Relativity, The Special and General Theory." It's amazing.
 
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And to further add confusion , if 2 trains are travelling at the speed of light and one person moves toward the fron of the train , are they travelling faster than the speed of light?
 
And to further add confusion , if 2 trains are travelling at the speed of light and one person moves toward the fron of the train , are they travelling faster than the speed of light?

Unpossible. With our current understanding of the universe, nothing with mass can travel at or above the speed of light.
 
These are enternal mind breakers... but they all boil down to relativity and frame of reference - mostly the latter.

If you were on some spaceship going near the speed of light, and you would shine a flashlight forward, to you, it would appear to operate completely normally, with the beam going away at light speed.

To a stationary observer things would be very different - he'd see a spaceship zooming by with a light beam travelling out of that a at very low relative speed.

With these thought experiments its paramount to consider your frame of reference - are you on the spaceship, on the slightly faster one, or a stationary observer?

yeah thats basically what I was saying. you would need a "stationary" observer for the ships to be going near lightspeed with respect to.

And to further add confusion , if 2 trains are travelling at the speed of light and one person moves toward the fron of the train , are they travelling faster than the speed of light?
the faster to lightspeed an object gets relative to us, the slower time seems to operate for it. so the person walking would be walking very slowly. i guess it also makes sense if the kinetic energy he would be supplying himself in normal time would be equal to the kinetic energy he supplies himself at that speed relative to us, but because to us his mass is greater, he moves alot slower. also, if somehow they reached lightspeed, time would stop moving for him (as we see it) so he wouldnt move faster than lightspeed at all since he cant move lol.
 
an example of mass moving at the speed of light using your traing theory...

1 train car has an engine strong enough to move it at the speed of light... but the drag created getting it to the speed of light would equal over 1 million attached a cars all needing their own engines, all creating their own drag.

michael
 


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