Time and approaching the Speed of Light

[Diaboro]

Hi, I'm trying to make a presentation about light and would like to include some interesting facts when presenting. I'm not a physics or a physics major, so I need your help . From my understanding, the more energy driving an object with mass, the more spacetime warps. Now this got me thinking of something and I was wondering if this is true or not.

 

Let's say we have three people. Person A, Person B and Person C. They're all at an Olympic stadium. Person A is on the stands and he's going to watch Person B and Person C race around the track. The race is set to an infinite number of labs. Person B has some sort of a superpower, and the energy driving him doubles every few seconds. Person C is just a regular runner.

 

Now what from my understanding, Person B is going to accelerate faster and faster until he reaches 99.9% the speed of light. But as he the energy driving him increases further and further, spacetime should also warp. Now my question is, would Person B, eventually, warp space time so much that Person A (The guy in the stadium) would see him slowing down and Person B passing him, or would he hit the limit before then and becomes a blackhole? and if the limit never existed, would this happen?

 

Appreciate your help!

[richardings]

I think:

As person B accelerates to nearly c, he will warp space time a ridiculous amount. This means he will exert a lot of gravitational force on his surroundings, and also he will perceive time in his surroundings moving alot faster, as well as his surroundings perceiving him moving slower. so it will seem to person B, that person C is moving alot faster than he actually is. I haven't worked it out, but I believe that person A will still see person B moving faster, as he is running STUPIDLY faster. you also have to take into account the fact that person C is on the race track with person B, so he will be in an area of space-time that is significantly warped too. Also im not sure, but i think having the mass of a person going at 0.999c will probably cause i black hole.

 

im not an experienced physicist tho so im not sure

[Janus]

Here's what happens:

 

As B increases his energy his speed increases. At first doubling his energy will increase his speed by ~41%. However as his speed increases, this increase in speed will get smaller and smaller. At 60% of the speed of light, doubling his energy will only result in a 24% increase in speed. As he gets closer and closer to the speed of light, this increase continues to shrink so that his speed always remains slower than light. The person in the stand will see him always getting a little closer to the speed of light, but never reaching it. Thus he will always be ahead of the other runner.

[khorto20]

I was under the impression that mass isnt effected by velocity or acceleration. Can someone explain how a fast moving person of regular mass would create a black hole effect? Is a gravitational field generated by some other means than the person's mass?

[ACG52]

I was under the impression that mass isnt effected by velocity or acceleration. Can someone explain how a fast moving person of regular mass would create a black hole effect? Is a gravitational field generated by some other means than the person's mass?

 

Your impression is correct. Relativistic mass does not affect the gravitational field. An energy field can also produce gravity, but again, not relativistic energy.

[PureGenius]

Person a would observe the increase in speed in person b and would continue to watch thier speed increase until only a streak of light person c would b unable to observe person b at even 99.9 % the speed of light as thier observation point is too close to the accelerating object . Person b would continue to grow in gravitational strength and time space would then curve around them reducing their time flow by a factor of approx 5 times reduction their observation perceptually would b that they were moving slowly but everything outside thier field would in turn sped up by a factor of 5.Therefore the observer a would then witness person b disappear. Person cs time frame reference would b affected by bs excessivly high velocity only when b passed by person c as in his immidiate surroundings would blur and wobble as person b passed by in electromagnetic proximity ...

[swansont]

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Moderator Note

Question specifically about the workings of general relativity (and not about time) split http://www.scienceforums.net/topic/74526-q-on-general-relativity/#entry740398

[robomont]

shouldnt it also be split into math since they are using math to formulate?

maybe also split into science since its science?maybe just butcher the thread until its not recognizable?we got to confuse the sciences.dont want people getting too close to the truth.no wonder there is no traffic on this site.

[ydoaPs]

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Moderator Note

If you'd prefer to not have a vacation soon, you probably shouldn't take threads off topic solely to troll the staff.

[J.C.MacSwell]

If he could, somehow, go fast enough around the oval track of an Olympic Stadium, he would indeed create a blackhole. His own mass would not increase, but the mass of the system he is part of would.

[ACG52]

If he could, somehow, go fast enough around the oval track of an Olympic Stadium, he would indeed create a blackhole. His own mass would not increase, but the mass of the system he is part of would.

 

No he wouldn't. Relativistic 'mass' does contribute to gravitational force. Only rest mass generates gravity.

[J.C.MacSwell]

No he wouldn't. Relativistic 'mass' does contribute to gravitational force. Only rest mass generates gravity.

That's not correct. For, say, the moon orbiting the Earth, the Earth is greater than the sum of it's parts...all the kinetic energy bound in the system (just like the runner on the oval track) adds to both the gravitational, and equally the inertial, mass of the Earth. Note how this is effectively different from a straight line kinetic energy.

 

edit: essentially changed to effectively

Edited June 5, 2013 by J.C.MacSwell

[imatfaal]

That's not correct. For, say, the moon orbiting the Earth, the Earth is greater than the sum of it's parts...all the kinetic energy bound in the system (just like the runner on the oval track) adds to both the gravitational, and equally the inertial, mass of the Earth. Note how this is effectively different from a straight line kinetic energy.

 

edit: essentially changed to effectively

JCM - would I be right in thinking that this is along the lines that the constant velocity in a straight line is frame dependent whereas there is no inertial frame that would not note the difference in "all the kinetic energy bound in the system" with/without the moon in orbit

[PureGenius]

He would not become a black hole only highly energized and creating a time differential of 5 times slower time passage from outside of this brightly glowing time differential one could only witness a brightly glowing motion frozen in space.

[ACG52]

He would not become a black hole only highly energized and creating a time differential of 5 times slower time passage from outside of this brightly glowing time differential one could only witness a brightly glowing motion frozen in space.

Please provide your calculations for this.

[zapatos]

...one could only witness a brightly glowing motion frozen in space.

Can you explain what you mean? It sounds like you are saying that 'you will see motion that is not moving'.

[PureGenius]

I'm saying you would see a highly energized version of the object that would appear almost like an negative photo in appearance just before the speed of light was reached That frozen image would then frame drag across the visual spectrum. Of course I could be wrong maybe there is reason a black hole would be created but it seems highly improbable.

[imatfaal]

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Moderator Note

 

Pure Genius

 

Please stop answering mainstream questions in the physics forum with speculations and your own ideas. If you do wish to posit an answer to a topic which uses unconventional physics create a new thread in speculations.

 

Do not respond to this moderation within the thread - report the post if you feel it is unjust

 

[Delbert]

Speed is relative. There is no absolute 'speed' for anything. The speed of light is the same for everybody.

 

We talk about what it's like to travel at the speed of light without any reference as to what we're doing right now. But as above that's a non-argument because there's no absolute speed! Speed can only be referenced to something else.

 

Presumably to accommodate the above person B sees or experiences the stadium shrink and person A age much faster. With person A seeing person B age much slower. With person C experiencing something in between. The stadium only shrinks for person B, person A won't see the stadium shrink; for the same reason that the operators of the LHC don't see the LHC shrink when particles are whizzing round the thing at 99.9% the speed of light. The particles (if one could endow them with feeling!), sense the LHC to shrink. Whereas the operators see them heavier and age much slower.

 

Think that's about it. But others might know better.

 

Anyway, perhaps taking all this a tad further: mass, speed, time and perhaps everything is all relative. So what does that say about the universe?

Edited July 29, 2013 by Delbert