I c said the old man

[disappoint]

So I was thinking....

Yeah I know but I do it anyway.

So I was thinking....

If you travel near c you grow older slower therefore you "time travel" ahead into the future faster then your slower brethren.

Do you have to cover any significant distance? Or could you just "vibrate" back and forth really fast?

So what if you could oscillate a human really fast back and forth at near c speeds? Like a tiny fraction of a mm perhaps? Ok I dunno how you'd accomplish it, maybe some magnets strapped to you and realy huge magnets pushing and pulling you.

Or what if it was even smaller distance than that? What if it was say a fraction of a nm? OK its a short distance but if the vibration is fast enough...Well would it pose a threat to you I mean would you fall apart or could you time travel?

Yeah nutty idea I know.

 

[Mr. Pedantic]

I think if you did that you would cause extensive bruising and internal bleeding, as well as brain damage and possibly several fractures. It would not be a good idea. Especially since nearing c mass would increase, further increasing the effect. With the acceleration involved you may even just compress the body into a sliver. Even if you found out how to do that, you would still suffer from the problem that you'd be only traveling at c for part of the time. Which makes it really useless. You may as well just spend the energy getting them into space and traveling at 0.9999c or something.

 

[disappoint]

I think if you did that you would cause extensive bruising and internal bleeding, as well as brain damage and possibly several fractures. It would not be a good idea. Especially since nearing c mass would increase, further increasing the effect. With the acceleration involved you may even just compress the body into a sliver. Even if you found out how to do that, you would still suffer from the problem that you'd be only traveling at c for part of the time. Which makes it really useless. You may as well just spend the energy getting them into space and traveling at 0.9999c or something.

Internal bleeding, bruising, fractures from moving a fraction of a nanometer?

 

[KIAman]

Internal bleeding, bruising, fractures from moving a fraction of a nanometer?

Nope, rather you would simply lose all connectivity and decompose into quantum particles.

 

[Daedalus685]

Internal bleeding, bruising, fractures from moving a fraction of a nanometer?

Damage in a car accident, for instance, is merely a function of the speed and the time it takes to stop. F=ma and all that, so you can figure out the force you are under based on the time (acceleration) it takes to come to rest. If you are going 100Km/hr and hit a giant marshmellow that stops you after 100ft vs a diamond wall that stops you over the length of the now flat car you will very quickly know the difference.

The force involved in accelerating from 0 to c over a mm would be such that your body would be vapourized into a blindingly hot plasma. Ignoring problems with how difficult (read: impossible) it would be to accelerate that fast.

 

[DrPizza]

Do you have any idea how much energy it would take to have an 80kg (rest mass) human accelerate from +0.9999c to -0.9999c in a very very very short amount of time? (I'm not sure whose time.)

 

[Mr. Pedantic]

Internal bleeding, bruising, fractures from moving a fraction of a nanometer?

Maybe that was an understatement. To daed's example, traveling at a given speed inherently poses no danger; it's how you get up there that's dangerous. In most situations having an acceleration above about 50m/s^2 is dangerous, because your heart cannot pump enough blood to effectively perfuse the brain, and your venous blood does not have enough pressure to force the blood back up into the heart from your extremities. That's with 50m/s^2. To get from 0 to c in the space of half a millimeter, your acceleration would be 90,000,000,000,000,000,000m/s^2 (I think I put the right number of 0s in). At that point, whatever molecules the acceleration would be acting upon would just go right through the rest of your body. I don't think the atoms would even be able to stay together.

 

[Mark R]

Do you have any idea how much energy it would take to have an 80kg (rest mass) human accelerate from +0.9999c to -0.9999c in a very very very short amount of time? (I'm not sure whose time.)

Heh.

Just to put the numbers into perspective, I worked out how much force would be required to accelerate a 70 kg mass from 0 to 0.99c in 1 mm.

The force comes out at 7 x 10^21 N. The time taken to travel 1 mm is 5 x 10^-12 s. Kinetic energy is 4 x 10^19 J.

Edit:
Except I've probably done something wrong because F.x doesn't equal E. I wonder what.

 

[BurnItDwn]

That would be awesome .... pretty much the acceleration required would everything apart ... sorta like two semi tricks each pulling on the opposite end of a tiny string.

 

[Mr. Pedantic]

Except I've probably done something wrong because F.x doesn't equal E. I wonder what.

Relativity, maybe?

 

[Mark R]

Relativity, maybe?

I thought I'd taken that into account in my equations of motion. I guess I must have screwed it up.

Taking Mrel = Mrest / (sqrt (1-v^2/c^2)) - from relativity

and

F = Mrel . a - I'm guessing this holds in relativity

integrating gives

v = c . (1- tan (qt) cos (qt))
where q = F/(c . Mrest) and is constant

integrating again gives
s = c . (1 - cos (qt)) / q

 

[Daedalus685]

Except I've probably done something wrong because F.x doesn't equal E. I wonder what.

Not sure... Rounded to oblivion I get:

3e18 from .5*70*(.99*2.98e8)^2 for energy

and

3e21 from 70*a, where a = (.99*2.98e8)^2/(2*1mm)

At any rate.. big numbers...


Though note that these numbers are not correct given they are relativistic and simply using regular old newtons laws.. If you used special relativity to find the values (not gonna bother, time to go home) your values would be different.

 

[TuxDave]

nvm, you did.

 

[Nathelion]

This could theoretically be done, if you could find some way to make the force act uniformly on all the particles in your body. The only way I can think of doing that would be with gravity, which poses some pretty severe problems. But you could do it for, say, a single elementary particle. However, I would recommend spinning it in a circle instead, since it would require less acceleration and be more efficient (with back-and-forth motion, you spend a significant amount of time travelling at slower speeds as you accelerate, whereas spinning in a circle, you would always be travelling at your higher speed relative to the earth inertial frame). Presto, you have a particle accelerator! One could, of course, make the "ring" you spin around so large that the acceleration would be tolerable for a human. Calculating how large it would have to be is an exercise that I will leave to some other diligent poster, I'm just too rusty with those relativistic equations.

 

[Howard]

This could theoretically be done, if you could find some way to make the force act uniformly on all the particles in your body. The only way I can think of doing that would be with gravity, which poses some pretty severe problems. But you could do it for, say, a single elementary particle. However, I would recommend spinning it in a circle instead, since it would require less acceleration and be more efficient (with back-and-forth motion, you spend a significant amount of time travelling at slower speeds as you accelerate, whereas spinning in a circle, you would always be travelling at your higher speed relative to the earth inertial frame). Presto, you have a particle accelerator! One could, of course, make the "ring" you spin around so large that the acceleration would be tolerable for a human. Calculating how large it would have to be is an exercise that I will leave to some other diligent poster, I'm just too rusty with those relativistic equations.

I think you would just die from dizziness.

 

[Elias824]

Your body stopping instantly before accelerating in the opposite direction after you were going nearly the speed of light would be very very bad. My gut reaction is that rather then aging slower then everyone else, you would stop aging altogether.

 

[MrDudeMan]

This could theoretically be done, if you could find some way to make the force act uniformly on all the particles in your body. The only way I can think of doing that would be with gravity, which poses some pretty severe problems. But you could do it for, say, a single elementary particle. However, I would recommend spinning it in a circle instead, since it would require less acceleration and be more efficient (with back-and-forth motion, you spend a significant amount of time travelling at slower speeds as you accelerate, whereas spinning in a circle, you would always be travelling at your higher speed relative to the earth inertial frame). Presto, you have a particle accelerator! One could, of course, make the "ring" you spin around so large that the acceleration would be tolerable for a human. Calculating how large it would have to be is an exercise that I will leave to some other diligent poster, I'm just too rusty with those relativistic equations.

This is along the lines of what I was going to say. My only addition would be to point out that it is illogical to discuss this device, and not because it is probably impossible, but because it is unnecessarily more complicated than it has to be. Making the range of motion bigger gives the same outcome with fewer constraints. If you wanted to age at some rate compared to the nominal aging speed of a human, simply shoot them off into space for a given distance and then turn them around and send them home. They could travel millions of miles in a straight line or millions of miles by oscillating with an amplitude of 1mm and the result would be the same. The difference is the first version is more reasonable, at least in the context of this discussion.

 

[Ninjahedge]

Last minute 2¢

If you accelerated every particle in a persons body uniformly, then nothing would happen to them. the main problem we have with acceleration is that it is usually a locally applied force (to your feet, your back, your backside). You accelerate too fast and the blood drains from certain parts and cannot circulate, rendering you unconcious.

Up the scale and you start blowing out blood vessels and damaging soft tissue. Next is hard tissue, and extreme would be the possibility of maybe even riping you down to atoms.


But you push on ALL of them to move them all at the same time you would not feel anything (until maybe the vector sum of your parts motion got so close to limiting factors like the speed of light that that extra m/s was enough to change its relation to space time.....).

As for oscilation? It would probably do the same, but only as the integration of its velocity over time in relation to the time dialation effect. You would not be spending all your time near "c" unless you were oscilating in a saw-tooth (which is a physical impossibility, although we could probably get CLOSE to it with extreme acceleration applied instantaneously at each end of the wave form (top and bottom)).

But whatever.

There are probably easier ways to catch a buzz.

 

[Gurgitate]

So I was thinking....

Yeah I know but I do it anyway.

So I was thinking....

If you travel near c you grow older slower therefore you "time travel" ahead into the future faster then your slower brethren.

Do you have to cover any significant distance? Or could you just "vibrate" back and forth really fast?

So what if you could oscillate a human really fast back and forth at near c speeds? Like a tiny fraction of a mm perhaps? Ok I dunno how you'd accomplish it, maybe some magnets strapped to you and realy huge magnets pushing and pulling you.

Or what if it was even smaller distance than that? What if it was say a fraction of a nm? OK its a short distance but if the vibration is fast enough...Well would it pose a threat to you I mean would you fall apart or could you time travel?

Yeah nutty idea I know.

You'd be instantly liquified. Imagine a trillion jackhammers pounding every millimeter of your body.

But what if you could move every atom at the same time in the same direction? Would you stop aging and be perfectly preserved for all eternity, or would the individual molecules still degrade?