Time Travel - Page 2

Sikander · August 22, 2003, 04:14

What are the best pieces of Time Travel fiction in your opinions?

DAVOUT · August 22, 2003, 04:18

The only way to measure time is to measure movements of physical particles; in a universe where nothing moves, the concept of time would not exist.

The relativity law states that for to bodies moving differently (in speed or direction), the flow of time is not identical : how travelling in time could be possible if most moving particles (and our present universe is made of moving particles) follows different flows of time?

Richard Bruns · August 22, 2003, 11:15

Quote:

Originally posted by Sikander
What are the best pieces of Time Travel fiction in your opinions?

Tinothy Zahn wrote a really good short story called "The Time Bomb" but it would be really hard to find. I read it in an old short story collection from a secondhand bookstore.

Basically, the premise is that simply knowing how to build a time machine causes disruptions in the space-time continuum around the person who has the knowledge, simply because of what might happen if the time machine were used to change something.

For example, cigarettes crumble into dust around the scientist because he knows that someone might want to use the time machine to go back and prevent the cultivation of tobacco and subsequent establishment of the tobacco industry.

They actually tried to build a time machine, and as they did so, these disruptions became so severe that the electronic compopnents, and the lab itself, fell apart faster than they could put the machine together.

So the possibility of going back in time and changing things causes distortions in space-time that prevent you from ever actually going back in time. A very cool paradox.

Kuciwalker · August 22, 2003, 11:20

Quote:

Originally posted by Gatekeeper
The only way time travel should be possible is if, when you go back, you cannot physically interact with the past. Failing that (or on top of that), every time you go back, you spawn a separate timeline from the one you came from. These timelines all remain "bundled" together (think individual lanes in a super-super timeline highway of human possibilities), but passage among them is even harder than traveling through time.

It's all SF. Or is it?

Gatekeeper

If you cannot physically interact with the past, then for all intents and purposes you aren't there. You'd have no mass - as gravity would be an interaction. You couldn't see anything - because absorbing photons would be an interaction. You couldn't feel things - because matter resisting you passing through it would be an interaction.

All observation is interaction.

Kuciwalker · August 22, 2003, 11:22

Quote:

Originally posted by Richard Bruns
Tinothy Zahn wrote a really good short story called "The Time Bomb" but it would be really hard to find. I read it in an old short story collection from a secondhand bookstore.

Basically, the premise is that simply knowing how to build a time machine causes disruptions in the space-time continuum around the person who has the knowledge, simply because of what might happen if the time machine were used to change something.

For example, cigarettes crumble into dust around the scientist because he knows that someone might want to use the time machine to go back and prevent the cultivation of tobacco and subsequent establishment of the tobacco industry.

They actually tried to build a time machine, and as they did so, these disruptions became so severe that the electronic compopnents, and the lab itself, fell apart faster than they could put the machine together.

So the possibility of going back in time and changing things causes distortions in space-time that prevent you from ever actually going back in time. A very cool paradox.

Not that any of that is actually possible...

Kuciwalker · August 22, 2003, 11:30

The thing about time travel is that, for it to work, it requires that all times exist "simultaneously". There are two results of the existance of time travel:

In the first, time travel would never change the past, because when it did, the future would be altered, which would alter the alteration of the past, which would alter the alteration of the future which would then alter the alteration of the past, and this would keep "happening" until a stable configuration emerged, one that altered itself to be itself. Since all times are "simultaneous", this would happen in zero time, and so we are living in that stable configuration.

The second possibility is similar to the first (in fact, the first could be a subset of this), but it makes things easier to understand. There would be a second time dimension. This is very similar to the idea of a "multiverse", in that it would really be an array of spacetimes. You are traveling in both time dimensions. When you go back in time, however, you go back in only the first time dimension - it's impossible to go back in the other. You thus end up in a different spacetime at an earlier time along the first time dimension. However, you cannot go back along the second time dimension. Thus, you cannot interact with the past of your own spacetime, only another. This is basically what the theory was in Timeline.

DAVOUT · August 25, 2003, 10:40

The Physical Concept of Time

http://www.rzuser.uni-heidelberg.de/...ection/Ch1.pdf

Interesting although helpless for time travel

:

Sava · August 25, 2003, 10:42

perhaps no one has come back because the future hasn't happened yet...

DAVOUT · August 25, 2003, 10:56

Quote:

Originally posted by Sava
the future hasn't happened yet...

Is not it why we name it the future ?

Sava · August 25, 2003, 10:59

Quote:

Originally posted by DAVOUT
Is not it why we name it the future ?

well, for time travelers to come back FROM the future... the future would have had to happen... but it hasn't... so they won't.

ricketyclik · August 25, 2003, 11:03

Quote:

Originally posted by johncmcleod

This gives me an awesome idea for a novel. Mankind is about to wipe itself out. So some smart people are sent back in time to steer the world leaders away from destroying ourselves. Of course they wouldn't tell the public or anything.

And obviously, Bush didn't get one of these advisors.

If mankind is about to wipe itself out, there is no future from which to return.

DAVOUT · August 25, 2003, 11:09

Quote:

Originally posted by Sava
well, for time travelers to come back FROM the future... the future would have had to happen... but it hasn't... so they won't.

So we get rid of all other posters of this crazy thread ? Not necessarily a bad thing.