Time Travel

[Guest]

@TG:

Therefore, you could travel faster than a lightpulse through the usual space-time to the same destination, that effectivly would be time travel.
(but if you travel back, you don’t arrive earlier than you started, so some of the paradoxa against time travel don’t hold).

Wormholes will just cut the amount amount of time spent traveling - I don’t see traveling backwards into time (cerca 1000 BC). There is, of course, no experimental confirmation that such wormholes exist, or that any finite-sized body could take the short-cut without being torn apart if they do.

You can’t go back in time and stay at the same place, as mentioned above.
Unless of course, if you use a wormhole, and this wormhole connects two places in space time in a special manner, then you could.
That special manner would be: the exit point must be further back in time than the amount of time you need to travel (with speed of light) from there to the entrance along the “normal space”.

And, well, if wormholes are made up of two black holes, then traveling those will be sightly more difficult than all Star Trek technology :)

[Xi]

@F_alk:

Example: You travel one lightyear, stay there a second, and travel back. Then all you noticed is the one second you stayed, while at the starting/arriving point, two years and a second have passed.

Does anybody really know what time it is!? (or is it ?!)

This time and or time/space travel Sci-Fi technology was the part with which I always had trouble. For example, if I were to travel in time and space from here to Beta Centauri :P 100 years in the past. How do I account for the movement of the target’s rotation in space, revolution around its’ star, movement through space caused by nearby celestial bodies ( :P woo woo) and the expansion/contraction of the universe, etc.? Even worse, if I travel into the future, I may not be able to account for an asteroid striking the planet. No planet? I cannot even drop a coupla inches I was off target. Or into the past, if I time travel past an asteroid striking the Earth, I might materialize inside the planet … buried alive … or would it be materializes with dirt in my lungs, bowels and other body cavities. :oops: Oow! - Xi

[Yanny]

You got a point, a Black Hole’s gravity is so strong not even light can escape it, right? Speaking from 8th Grade Physics here.

[TG Moses VI]

Unless of course, if you use a wormhole, and this wormhole connects two places in space time in a special manner, then you could.

And where would you find enough antigravity to keep the well open, let alone fit a spaceship through it? Sorry, there are better means then using wormholes if we’re talking about time travel.

You can’t go back in time and stay at the same place, as mentioned above.

Exactly.

You got a point, a Black Hole’s gravity is so strong not even light can escape it, right? Speaking from 8th Grade Physics here.

I dunno, us Californians aren’t very smart - at least that’s what standards show. :-?

[Xi]

GO jump in a black hole! - Xi

[Guest]

@Xi:

Does anybody really know what time it is!? (or is it ?!)

This time and or time/space travel Sci-Fi technology was the part with which I always had trouble. For example, if I were to travel in time and space from here to Beta Centauri :P 100 years in the past. How do I account for the movement of the target’s rotation in space, revolution around its’ star, movement through space caused by nearby celestial bodies ( :P woo woo) and the expansion/contraction of the universe, etc.?

We do have a picture of what time is, and up to now it serves us pretty well. Actually, we have several pictures, and all serve well in some accounts, but they are not fully compatible :D

So, if you move to Beta Centauri….
You need of course to calculate where the star will be etc etc, probably, you would travel “close” to it (at max speed), and do the final maneuvers at “impluse drive” :), much slower.

Even worse, if I travel into the future, I may not be able to account for an asteroid striking the planet.

Well, you need to know what will happen, as said above. Fortunately asteroids do not come out of nowhere, so if you know when and where they are, you can navigate around it. …
But yes, having that computational power and first of all the data you need (seeing asteroids there from here) would be yet another task to solve :D

@Yanny:

You got a point, a Black Hole’s gravity is so strong not even light can escape it, right? Speaking from 8th Grade Physics here.

Yup. Nothing / nothing useful (that is being discussed, wether there can be some kind of information leakage or not) can escape a black hole.

@TG:

Unless of course, if you use a wormhole, and this wormhole connects two places in space time in a special manner, then you could.

And where would you find enough antigravity to keep the well open, let alone fit a spaceship through it? Sorry, there are better means then using wormholes if we’re talking about time travel.

Ach…. that’s “just” some practical questions. In theory, you just pull out your cool device that does what you need, and go on :D…
But, I am an experimentalist, and you are absolutely right with the first. For the second, i don’t believe that there are other ways, which means: i don’t believe we could travel in time.

[Xi]

The Xi Hole [not Pi Hole](Rainbow Plumbing) Hypothesis -

I) There are multiple hole (let us not limit ourselves to calling them black) entrances leading to the same destination. These multiple holes lead to a system we shall, henceforth, refer to as “Rainbow Plumbing.” Matter(asteroids, spacecraft, humans [all lifeforms would refer to themselves as humans in translation], light, etc., passing through a black hole merges with anti-matter entering the rainbow plumbing by another entrance we shall, for the moment, refer to as a “fuscia hole” to the rainbow plumbing. This intake by the rainbow plumbing must be a near 50/50 balance of matter and anti-matter.
a) There may be multiple (two or more) entrances to the rainbow plumbing from the matter and anti-matter universes.
b) There may be multiple (two or more) matter and anti-matter universes feeding the rainbow plumbing.
–------------------------------------
Submitted for your consideration,
this date of October 2, 2002,
your humble savant,

• Xi

[TG Moses VI]

For the second, i don’t believe that there are other ways, which means: i don’t believe we could travel in time

Sorry, I did not mean it in that way. I talking more about traveling long distances. Cosmic strings might work for that.

[Xi]

What? No complaints! …
I mean compliments! - Xi

[TG Moses VI]

What? No complaints! …
I mean compliments! - Xi

Where would you get the anti-matter from? What would you do with the energy once it is released?

[Xi]

Oops! Sorry, I meant to add that it all combined at the end of a “downspout” to form a “true matter universe.” - Xi

[Yanny]

Well, if Light cannot escape a Black Hole, how can we detect them?

[DeviantScripter]

I do not believe time travel is possible.

I think Stephen Hawking explained it best when he said that time travel is not possible because nobody from the future has visited us yet.

[cystic crypt]

@Yanny:

Well, if Light cannot escape a Black Hole, how can we detect them?

the same way you can detect something behind you - it casts a shadow (i.e. the absense of light)

[TG Moses VI]

@Yanny:

Well, if Light cannot escape a Black Hole, how can we detect them?

Well most of the known universe is shrouded in dark matter. Plus we can see X-ray and infra-red radiation signals given off from the strong gravity fields of a blackhole?

[DeviantScripter]

@F_alk:

Yup. Nothing / nothing useful (that is being discussed, wether there can be some kind of information leakage or not) can escape a black hole.

That’s wrong.

[Guest]

@Deviant:Scripter:

I do not believe time travel is possible.

I think Stephen Hawking explained it best when he said that time travel is not possible because nobody from the future has visited us yet.

Which is an experimentalists point of view, and one i agree (even if i think Hawking is usually overestimated ).

@Yanny:

Well, if Light cannot escape a Black Hole, how can we detect them?

@TG:

Plus we can see X-ray and infra-red radiation signals given off from the strong gravity fields of a blackhole?

Exactly, matter accumulates a lot of energy when falling towards the hole. Part of that energy is emitted as radiation. And as long as the matter has not fallen into the event horizon, this radiation still reaches us.

@Deviant:Scripter:

@F_alk:

Yup. Nothing / nothing useful (that is being discussed, wether there can be some kind of information leakage or not) can escape a black hole.

That’s wrong.

It’s not :)
(g9ving you as much evidence for my stance as you did for yours….)
why i am wrong ?

[DeviantScripter]

Well F_alk, I hate to use Stephen Hawking again, but I think I must:

“Black holes are usually thought of as objects with such strong gravity that nothing, not even light, can escape from them. However, Stephen Hawking has shown that black holes can radiate energy. The reason goes back to quantum mechanics and the uncertainty principle. For very brief periods of time, matter or energy can be created from “empty” space because no such thing as truly empty space exists. Hawking realized that if a particle/anti-particle pair came into existence near the event horizon of a black hole, one might fall into the hole before annihilating its anti-particle. The other particle could then escape the gravitational clutches of the black hole, appearing to an outside observer as radiation.”

[Yanny]

So, we cannot see the black holes themselves, but since the pull of it’s gravity is so strong, we can see the energy pooling up ready to be sucked in?

[cystic crypt]

@Yanny:

So, we cannot see the black holes themselves, but since the pull of it’s gravity is so strong, we can see the energy pooling up ready to be sucked in?

maybe consider them to be like magnetic fields (VERY crude analogy). a body/solution/molecule subject to a magnetic field (for example, in an MRI/NMR (nuclear resonance imaging) machine will become excited. This excitement has a signiture (likely multiple signitures) that may register in different ways. One of these might well be captured by: infra-red/spin-spin coupling/ etc. (i.e. something that does not get sucked into the black hole).
i hope this is a little clear - sorry, i’m no astrophysicist, however i do find imaging fascinating.