AntiHyper
Revered Member
Anything that orbits something is changing its velocity, so yeah earth is under constant acceleration due to the force of gravity (sun).
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Traveling at the speed of light! (1 Viewer)
- Thread starter physician
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SlaminSammy
Member
physician said:
I was listening to a man speak about objects that get pulled into black holes. He stated that an object in this situation could indeed pass the speed of light! SOOO traveling faster than the speed of light would definately be possible. However as it approached the event horizon, time would dialate to an extent that it stoped. The object relative to a stationary body (lets say we're on earth) would appear to just sit in its position in space where it precisely reached the speed of light and it would never move relative to us on earth.... MEANWHILE it has accelerated past the speed of light and been crushed into oblivion or what ever... energy or what not--- clearly i didnt do my own reseach on the matter.
so.... by this theory yes you would see the object... but never in the same way as light....
Raginsheep
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The physical laws we have currently completely break down when talking about stuff in the region of black holes. I wouldn't read too much into it.
Halfasian89
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My Opinion
Regardless to black holes, i would say that relatively speaking, the earth feels less acceleration than a spacecraft travelling close to the speed of light would. But the Earth does experience acceleration due to its rotation and revolution around the sun (ignoring accelerations within the solar system and beyond), for acceleration is measured as a vector quantity, that is, as a magnitude and direction. Earth revolves around the sun so it is indeed changing acceleration in that respect, and because the Earth (as with any orbit) is to a degree, eliptical, it has a variable radius, and in regard to the equation of orbital velocity [v= sqr root(Gm/r)], velocity of the earth (magnitude) also changes. But do we humans feel this acceleration (F=ma) on Earth? Hardly, because these accelerations over time are very minute on our scale, and that is why we regard earth as an inertial frame of reference. On the contrary, the spacecraft experiences accelerations before reaching great velocity, and on arrival to earth, must experience decceleration, and during these times it is regarded as a non-inertial frame of reference (where net force is not equal to zero).
On the twin paradox then, the twin in the spacecraft would be much younger than the twin on earth because it has experienced accelerations (and thus force) within his/her frame of reference, keeping in mind that the twin on earth feels next-to-nothing force in comparision. The twin on the spacecraft experiences time dilation as s/he experiences force, and to him/her, the time of his/her trip in space would be shorter than what the earth twin believes, and as such, the spacecraft twin will age more slowly.
On the speed of light, I personally don't believe that we can achieve speeds equal and beyond c (note that) because light in a vaccum is constant in any frame of reference, but when light travels through a medium (such as water) i say you could travel faster, but that wouldn't really achieve anything. I'm thinking that in between the collisions that take place when light travels through a medium, light travels at c, but the reason why it appears to be slow is that its path is not straight, and thus it must travel longer distances to reach the same point to light in a vaccum. The speed limit in the universe is 299 792 458 m/s. I do believe in the whole warp hole thing (part of string theory).
Einstien's postulate of a train travelling at the speed of light demonstrates that he would see his reflection in the mirror, and also that light behaves the same way in any frame of reference.
The example regarding black holes does make sense, but that only occurs in such an instance, where relativity and quantum physics meet (lots of conflicts). Relativity deals with objects of large masses, whereas quantum physics deals with very small objects. In a black hole you have both, so things become very dirty, and im sure that scientists haven't resolved that problem.
The ceasium gas thing, i have no idea.
Opinions?
Regardless to black holes, i would say that relatively speaking, the earth feels less acceleration than a spacecraft travelling close to the speed of light would. But the Earth does experience acceleration due to its rotation and revolution around the sun (ignoring accelerations within the solar system and beyond), for acceleration is measured as a vector quantity, that is, as a magnitude and direction. Earth revolves around the sun so it is indeed changing acceleration in that respect, and because the Earth (as with any orbit) is to a degree, eliptical, it has a variable radius, and in regard to the equation of orbital velocity [v= sqr root(Gm/r)], velocity of the earth (magnitude) also changes. But do we humans feel this acceleration (F=ma) on Earth? Hardly, because these accelerations over time are very minute on our scale, and that is why we regard earth as an inertial frame of reference. On the contrary, the spacecraft experiences accelerations before reaching great velocity, and on arrival to earth, must experience decceleration, and during these times it is regarded as a non-inertial frame of reference (where net force is not equal to zero).
On the twin paradox then, the twin in the spacecraft would be much younger than the twin on earth because it has experienced accelerations (and thus force) within his/her frame of reference, keeping in mind that the twin on earth feels next-to-nothing force in comparision. The twin on the spacecraft experiences time dilation as s/he experiences force, and to him/her, the time of his/her trip in space would be shorter than what the earth twin believes, and as such, the spacecraft twin will age more slowly.
On the speed of light, I personally don't believe that we can achieve speeds equal and beyond c (note that) because light in a vaccum is constant in any frame of reference, but when light travels through a medium (such as water) i say you could travel faster, but that wouldn't really achieve anything. I'm thinking that in between the collisions that take place when light travels through a medium, light travels at c, but the reason why it appears to be slow is that its path is not straight, and thus it must travel longer distances to reach the same point to light in a vaccum. The speed limit in the universe is 299 792 458 m/s. I do believe in the whole warp hole thing (part of string theory).
Einstien's postulate of a train travelling at the speed of light demonstrates that he would see his reflection in the mirror, and also that light behaves the same way in any frame of reference.
The example regarding black holes does make sense, but that only occurs in such an instance, where relativity and quantum physics meet (lots of conflicts). Relativity deals with objects of large masses, whereas quantum physics deals with very small objects. In a black hole you have both, so things become very dirty, and im sure that scientists haven't resolved that problem.
The ceasium gas thing, i have no idea.
Opinions?
shinji
Is in A State Of Trance
can't be bothered readin 3 pages .. so yeh.
when u travel at the speed of light, u 'supposedly' convert into energy.
the onli things that would slow down would be the things in the frame of reference of the person travelling at the speed of light.
it's not really time travel per se' ; but time just "slows" down. so reviewing the past would be impossible, as (explained in time machine) when u go back into time, u weren't created and neither was the actual time machine, so u supposedly don't exist.
u'll only be able to "travel" into the future ...
when u travel at the speed of light, u 'supposedly' convert into energy.
the onli things that would slow down would be the things in the frame of reference of the person travelling at the speed of light.
it's not really time travel per se' ; but time just "slows" down. so reviewing the past would be impossible, as (explained in time machine) when u go back into time, u weren't created and neither was the actual time machine, so u supposedly don't exist.
u'll only be able to "travel" into the future ...
Laids
New Member
ok heres something else to think about in regards to time dilation.
Say in the scenario with the two twins, one on earth and one on a space ship travelling at teh speed of light. Say that their were two atomic clocks, onee on Earth and one on the spaceship with video cameras recording them and sending the signal to the other location. Both twins can see the clock that is their with them, and the clock that is with their twin. They should both appear to be ticking at the same time, so does this mean that time dilation will not happen?
Say in the scenario with the two twins, one on earth and one on a space ship travelling at teh speed of light. Say that their were two atomic clocks, onee on Earth and one on the spaceship with video cameras recording them and sending the signal to the other location. Both twins can see the clock that is their with them, and the clock that is with their twin. They should both appear to be ticking at the same time, so does this mean that time dilation will not happen?
In the frame of the Earth, the Earth clock always shows more time than the spaceship clock, because of the time dilation of the spaceship with respect to the Earth. The time delay due to the finite speed of light simply enhances the effect, making the spaceship clock appear slower than it actually is.
tacuric
New Member
no i doubt that you could. It would depend o your frame of reference.physician said: