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the_merv · 2005-09-04 23:27:34

Hi, forgive me if i make false assumptions etc. I'm not academically trained as a physicist, its just an obsession .

From what I understand if one ignores the practicalities(which are huge to overcome) time travel is possible. All you need is a stable and large enough wormhole, and a ship capable of accelerating a human to 99.9% of the speed of light that would not result in the fragile human body being pulverised. Creating a wormhole sounds like a difficult task but as far as i know at the ultra microscopic level through quantum jitters in the fabric of spacetime wormholes are being created the whole time. If one could create enough negative pressure within the wormhole, one could use gravity to stretch the wormhole out thus allowing a human to fit through it. lets say that one end of the wormhole is in my bedroom and the other is in this very fast spaceship. The spaceship circles the earth at almost the speed of light for a few hours, the spaceship would have only experienced a few hours but according to relativity the earth would have been going on for a good few million years. THe space ship could land on this future earth and i could walk from my bedroom in the present through the wormhole to the ship that is on an earth millions of years from now, thus travelling to the future. Could someone clarify whether this is a theoretical possibility or whether im barking up the wrong tree.

insomnia · 2005-09-05 09:40:26

To me it sounds like BS. As I think when you make a wormhole, the entrance and exit are created simultaneously and you can't move the entrance or exit.

Correct me if I'm wrong.

drowsy turtle · 2007-06-13 21:16:45

what makes this precious speed of light so important? It's just a speed, nothing more. As for wormholes, I'm yet to see a decent theory behind them, but I'm willing to read any articles or pages that prove otherwise.

Tina Bear · 2007-06-13 22:13:48

the speed of light is slow, gamma and xrays are much faster. gravity is instantious. wormholes do not exist and time travel is not possible.

jmg810 · 2007-09-19 14:16:20

drowsy turtle wrote:
what makes this precious speed of light so important? It's just a speed, nothing more. As for wormholes, I'm yet to see a decent theory behind them, but I'm willing to read any articles or pages that prove otherwise.

What makes the speed of light precious is that it remains at the same speed in any inertial reference frame. Because the speed of light is a constant in every inertial reference, we have the phenomena of time dilation and length contraction. These are topics of special relativity.

jmg810 · 2007-09-19 14:22:52

Tina Bear wrote:
the speed of light is slow, gamma and xrays are much faster. gravity is instantious. wormholes do not exist and time travel is not possible.

Actually the speed of light is very very fast! Also there isn't any difference between the speeds of gamma rays, x-rays, and light. In fact gamma rays, x-rays, and light all travel at the same speed! The reason this is so is that gamma rays, x-rays, and light are all the same phenomena, electromagnetic radiation. However what differentiates gamma rays, x-rays, and light is that they each have different frequency ranges.

Last edited by jmg810 (2007-09-19 14:24:36)

VastBlueSky · 2007-10-28 19:53:10

jmg is right, and not only that, but gravity is not instantaneous either. Besides the physical reasons for this (which I forget) it would not be consistent with it being impossible to transmit information faster that c. If gravity were instantaneous, if the sun disappeared we would know immediately, therefore transmitting information much faster than the eight and a half minutes the light takes to get here.

BenTheMan · 2007-11-01 15:11:41

VBS---This is essentially right. The reason is the second postulate of Special relativity, which says that nothing can go faster than the speed of light.

JulianH · 2008-04-21 12:08:09

On a similar note - I understand that one of the reasons that "speed of light" travel is unfeasible is that as you approach this speed, c, the mass of teh object travelling at this speed becomes unimaginably large. Presumaby electromagnetci radiation can only travel at this speed as it is massless (or close to it)

M@Man · 2008-04-22 03:15:35

One tidbit I learned in my general relativity course:

Yes, wormholes do link spacetime at different points, but, if you wanted to send something through it (intact, presumably), you would have to send it in on a trajectory that avoids the singularity. But in order to bypass the singularity and come out on the other side, you have to move faster than the speed of light. And if you could do that, you wouldn't need a wormhole in the first place.

Nicholas · 2008-05-10 06:32:05

The only time travel is into the future. This is accomplished by getting into strong gravity or very high near light speed motion. If you were to enter the strongest of gravitational fields you might spend a few minutes there by your time but when you come out the rest of the universe is a million years older. So what was a flash to you really was a million years to the outside universe. This is the relativity of time that allows you to travel into the future.

This is the only time travel possible: into the future of the rest of the universe.

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#1 2005-09-04 23:27:34

Time Travel is theoretically possible

#2 2005-09-05 09:40:26

Re: Time Travel is theoretically possible

#3 2007-06-13 21:16:45

Re: Time Travel is theoretically possible

#4 2007-06-13 22:13:48

Re: Time Travel is theoretically possible

#5 2007-09-19 14:16:20

Re: Time Travel is theoretically possible

drowsy turtle wrote:

#6 2007-09-19 14:22:52

Re: Time Travel is theoretically possible

Tina Bear wrote:

#7 2007-10-28 19:53:10

Re: Time Travel is theoretically possible

#8 2007-11-01 15:11:41

Re: Time Travel is theoretically possible

#9 2008-04-21 12:08:09

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#10 2008-04-22 03:15:35

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#11 2008-05-10 06:32:05

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