Time Travel question

[EXOTICLEX]

[ame]https://www.youtube.com/watch?v=ewj3wrIUR3s[/ame]

 

[Darkmatter]

JCVD's best movie!!!

 

[Intruder04]

You are asking this question on a toy forum? Also, someone who collects statues of the Hulk is asking it? Come on now.

 

[a-dev]

Any change to the past could be a serious **** up, no matter how 'right' it seems. Like if you went back and killed Hitler and prevented the holocaust. You could be wiping out countless people in your own time who would never be born because their grandparents didn't get together; they didn't get together because they instead met and married someone else who was originally killed in a gas-camp.

Unless changing the past merely sets up an alternate reality that runs parallel, the original reality remains unchanged. This is what seems to happen in Terminator. If it was all linear, one single timeline where affecting the past changes the future of that same timeline, then the resistance should never have had the chance to send protectors back to the past. Since Skynet had made the first move, their mission - from the 2029 POV - should have been an instantaneous success. The fact that the resistance had any opportunity at all to respond suggests that changing the past has no impact on that one particular reality. Rather it sets up another parallel one.

 

[Vitus]

lolll...how old are you and how much time in a day do you spend thinking about those things? lolll

buahahah stupidest post I read all day

 

[Intruder04]

Any change to the past could be a serious **** up, no matter how 'right' it seems. Like if you went back and killed Hitler and prevented the holocaust. You could be wiping out countless people in your own time who would never be born because their grandparents didn't get together; they didn't get together because they instead met and married someone else who was originally killed in a gas-camp.

Unless changing the past merely sets up an alternate reality that runs parallel, the original reality remains unchanged. This is what seems to happen in Terminator. If it was all linear, one single timeline where affecting past changes the future of that same timeline, then the resistance should never have had the chance to send protectors back to the past. Since Skynet had made the first move, their mission - from the 2029 POV - should have been an instantaneous success. The fact that the resistance had any opportunity at all to respond suggests that changing the past has no impact on that one particular reality. Rather it sets up another parallel one.

Agreed. This is what I was querying about originally. I just read about the grandfather paradox and Can-Not Because Has-Not theory

 

[Solidus]

I know many of us fantasise about time travelling and it might even be possible in the not-so-distant future. I've always wished to go back in time to undo all the wrongs I've done but there's always one question that bugs me.

If we travel back in time, for eg. to correct a mistake that we did, it would imply that we are changing our history. In other words, we are setting things right and by doing so, we are altogether eliminating the need to travel back cuz nothing ever went wrong. Thus creating an anomaly. Do you guys know any way outta this??

Well, most theoretical physicists today agree that traveling backwards in time would be impossible. Mostly because of the grandfather paradox. In the sense that, that if you go back in time to kill your grandfather, then you wouldn't have been born. And if you were never born, then you shouldn't have been able to "travel back" to kill your grandfather.

So, you'll have to live with whatever mistakes were made in life .

However, it is possible to slow down time. Space time will dilate in the presence of gravity. And if you can find a large gravitational source like a black hole, and achieve a close orbit around its event horizon (the region where the escape velocity equals the speed of light), your time will slow down relative to your surroundings. So, if you have a twin on Earth, and are orbiting closely around a black hole, you will age more slowly relative to your twin.

 

[a-dev]

Dammit. Killing my grandfather was the only reason I even thought of time travelling. Now I guess I won't even try.

 

[Solidus]

Dammit. Killing my grandfather was the only reason I even thought of time travelling.

Nooooooooo! Then there wouldn't be an a-dev, and SSF would be a very dull place without all of his Terminator knowledge .

Of course, you could take parallel universes into account. But, I really find it hard to believe that simply pulling a trigger and killing one's Grandpa, would automatically create an entirely new universe out of the "ether", just to correct itself .

 

[Intruder04]

Well, most theoretical physicists today agree that traveling backwards in time would be impossible. Mostly because of the grandfather paradox. In the sense that, that if you go back in time to kill your grandfather, then you wouldn't have been born. And if you were never born, then you shouldn't have been able to "travel back" to kill your grandfather.

So, you'll have to live with whatever mistakes were made in life .

There has to be a way around it. Thishttps://en.wikipedia.org/wiki/Temporal_paradox#Erased_timeline_hypothesis, this https://en.wikipedia.org/wiki/Temporal_paradox#Multiple_universes_hypothesisand thishttps://en.wikipedia.org/wiki/Temporal_paradox#Changes_allowed.2C_without_resolution_to_paradoxes seem hopeful. Just to say

However, it is possible to slow down time. Space time will dilate in the presence of gravity. And if you can find a large gravitational source like a black hole, and achieve a close orbit around its event horizon (the region where the escape velocity equals the speed of light), your time will slow down relative to your surroundings. So, if you have a twin on Earth, and are orbiting closely around a black hole, you will age more slowly relative to your twin.

Twins paradox. However, the intense gravity experienced whilst being that close to the black hole will have unknown physical effects.

Nooooooooo! Then there wouldn't be an a-dev, and SSF would be a very dull place without all of his Terminator knowledge .

Of course, you could take parallel universes into account. But, I really find it hard to believe that simply pulling a trigger and killing one's Grandpa, would automatically create an entirely new universe out of the "ether", just to correct itself .

Is the universe creating a parallel universe to heal itself after the killing or was it already in place before the killing?

Dammit. Killing my grandfather was the only reason I even thought of time travelling.

Just tell me his name

 

[Darth Snoopy]

 

[skooternb]

 

[BB&WSF]

I've always wished to go back in time to undo all the wrongs I've done...

[ame]https://www.youtube.com/watch?v=spKOib_D5YY[/ame]

 

[Solidus]

There has to be a way around it. This'https://en.wikipedia.org/wiki/Temporal_paradox#Erased_timeline_hypothesis', this 'https://en.wikipedia.org/wiki/Temporal_paradox#Multiple_universes_hypothesis'and this'https://en.wikipedia.org/wiki/Temporal_paradox#Changes_allowed.2C_without_resolution_to_paradoxes' seem hopeful. Just to say


Twins paradox. However, the intense gravity experienced whilst being that close to the black hole will have unknown physical effects.

The links aren't working. While, it's nice to fantasize about these things, science fiction from the movies has to be completely stripped away for any type of serious scientific discussion to take place. Truthfully, only about five-percent of peer reviewed papers on space time, parallel universes, etc, will ever get published on a yearly basis. It's not because those papers lack interesting theories, but it's because there's no empirical evidence to support any of the claims.

Well, this is SSF and I don't really expect much conversation outside of knowledge of pop-culture. But, just remember to take whatever you read on Wikipedia and elsewhere with a grain of salt .

As for what I mentioned about the black hole, if you're in a stable heliocentric orbit around its event horizon, you shouldn't even notice the effects of its gravity. That's because the inertial (or outward) force from the space ship would balance out the centripetal force from gravity that is directed toward the center of the black hole.

 

[AIR]

If it was ever possible, we would know about it by now.

If time travel were to ever be possible, how come nobody from the future has traveled back to a moment in recent history? Thoughts that keep me awake at night

 

[Intruder04]

https://www.youtube.com/watch?v=spKOib_D5YY

True dat but I wished I could just change one thing....errm, make it two!

The links aren't working. While, it's nice to fantasize about these things, science fiction from the movies has to be completely stripped away for any type of serious scientific discussion to take place. Truthfully, only about five-percent of peer reviewed papers on space time, parallel universes, etc, will ever get published on a yearly basis. It's not because those papers lack interesting theories, but it's because there's no empirical evidence to support any of the claims.

Well, this is SSF and I don't really expect much conversation outside of knowledge of pop-culture. But, just remember to take whatever you read on Wikipedia and elsewhere with a grain of salt .

As for what I mentioned about the black hole, if you're in a stable heliocentric orbit around its event horizon, you shouldn't even notice the effects of its gravity. That's because the inertial (or outward) force from the space ship would balance out the centripetal force from gravity that is directed toward the center of the black hole.

Links fixed. Yes, they are Wiki links and I do not take whatever I read there for granted.

Isn't a black hole a collapsing body? Wouldn't we have to constantly adjust our orbit in order to not have any ill-effects of gravity while at the same time use it for our time-slowing advantage?

If time travel were to ever be possible, how come nobody from the future has traveled back to a moment in recent history? Thoughts that keep me awake at night

Exactly what the can-not-has-not hypothesis outlines. Although, time-travelers may already be living among us, disguised.

 

[Solidus]

Links fixed. Yes, they are Wiki links and I do not take whatever I read there for granted.

Isn't a black hole a collapsing body? Wouldn't we have to constantly adjust our orbit in order to not have any ill-effects of gravity while at the same time use it for our time-slowing advantage?

Oh, no. Those type of black holes that you are referring to are stellar black holes and are already "collapsed" (as in the case of stars that are above the Chandrasekhar mass limit). The collapsing only happens once, and a stellar black hole will continue to lose its mass in the form of thermal energy and gamma ray bursts - provided that it's not drawing in any nearby matter.

A galactic black hole (like in the center of the Milky Way), on the other hand, was formed enormous rotating nebula and gas clouds. This type of black hole was never in a "collapsed" state, and just became millions of times more massive than the sun by feeding on matter.

The key thing to know, is that as long as a black hole (stellar or galactic) isn't "feeding" on matter, it's losing energy and evaporating.

Also, the more massive the black hole, the larger its event horizon. In order to effectively use that variation of the "Twin Paradox" that I mentioned before (which was postulated by Stephen Hawking by the way ), a galactic black hole will have to be used; in order to provide a large enough time dilation for the space ship, as well as a large enough orbital acceleration.

 

[a-dev]

I feel that the following is appropriate at this time.

[ame]https://www.youtube.com/watch?v=cFods1KSWsQ[/ame]

 

[The Ween]

If time travel were to ever be possible, how come nobody from the future has traveled back to a moment in recent history? Thoughts that keep me awake at night

Maybe.......they.......have......

 

[Frank]

I know many of us fantasise about time travelling and it might even be possible in the not-so-distant future. I've always wished to go back in time to undo all the wrongs I've done but there's always one question that bugs me.

If we travel back in time, for eg. to correct a mistake that we did, it would imply that we are changing our history. In other words, we are setting things right and by doing so, we are altogether eliminating the need to travel back cuz nothing ever went wrong. Thus creating an anomaly. Do you guys know any way outta this??

lolll...how old are you and how much time in a day do you spend thinking about those things? lolll

Old enough. Roughly 4-5 hrs a day.

You are creating a paradox right now by wasting so much time thinking about time travel. Your future self will want to go back in time and make you do something constructive like start your own polygamous cult! Look man, you will never be able to go back and keep those kids from flying your underwear on the flagpole at summer camp. Even if you could, I'm sure you'd still have an unexplainable fear of the national anthem.

But really hasn't this question been the focus of nearly every single time travel story out there? Come on man, you gotta make up your own mind and write a book.