Physicist Definitively Rules Time Travel Impossible

[Averant]

[sub]Serious response:
Call me a cynic if you wish but I'm reluctant to take his word as gospel.

Also I thought time was relative to gravity? Less Gravity present=faster flowing time? Time is also an artificial construct. Where I am at the moment (UK) I am living out the past of some people (those GMT+X) and the future of others (those GMT-X). If I wanted to be snarky I'd say you could time travel by flying round the world's timezones.
[./crackpot ill-educated troll-physics][/sub]

Less serious response: So I can rule out the possibility that I am in fact my own ancestor? Dammit I'd better get back to work on my family tree homework

Forgive me for any and all ignorance found in this post. I'm only a Junior in highschool. XD


I've actually somewhat formed my own theory for gravity. as for time being relative to gravity? Well, yes and no. Our frame of reference with time is c, the speed of light. Light is affected by gravity, ergo gravity affects time. Except it has to be a seriously dense gravity for it to have much effect on light, such as a black hole (thank you informative stargate episode...). Since it has little to no mass, it's basically our ruler for time. due to it's inability to be affected by anything other than a heavily dense mass gravity. Now that we've established time is based on light, let's look at time travel.

In order to travel back in time, you effectively need to rewind light. God, even thinking about this seriously makes me wonder how people could even think it possible. To travel backwards in time, you'd need to TURN BACK TIME, and since you can't reverse light, you can't reverse time. Even if you COULD, you'd need to do it on a universal scale, because if even one atom is out of place, it wouldn't be your past. It'd be an alternate dimension. Hence the original post about fucking up somebody ELSE's hitler. Even if you DID do all this time travel shit, and you DID kill our hitler... it wouldn't be our hitler anymore. It'd be ANOTHER hitler who died, and OUR timeline would be an alternate where hitler was still alive.

So, yeah. Time travel FTL. Try dimensional travel, and we might be talking.

 

[Trolldor]

One scientist?

Not good enough.

Give me a scientific consensus and I'll start paying attention.

 

[Tiamat666]

I saw this Stephen Hawking show about time travel and he believed that going backwards was impossible but going forward by traveling at near light speed was! just it is a one way ticket

Yeah. I thought that the relativity theory made it pretty clear that travelling into the future is possible.

 

[DRSH1989]

Traveling back and forward through time is a piece of cake. You just need a DeLorean...

 

[LogicNProportion]

Time Travel already didn't make sense before this guy threw a wall of text at it...

Simply put:

If in the history of time, if someone went back and did something, then it's already played out. Take, like, Hitler not being time-assassinated. If someone did indeed go back, it was already in the timeline that it would, thus, they failed.

This is hard to explain. Bleh. Go read the man's wall of text. I'm bored now.

 

[Scorched_Cascade]

[sub]Serious response:
Call me a cynic if you wish but I'm reluctant to take his word as gospel.

Also I thought time was relative to gravity? Less Gravity present=faster flowing time? Time is also an artificial construct. Where I am at the moment (UK) I am living out the past of some people (those GMT+X) and the future of others (those GMT-X). If I wanted to be snarky I'd say you could time travel by flying round the world's timezones.
[./crackpot ill-educated troll-physics][/sub]

Less serious response: So I can rule out the possibility that I am in fact my own ancestor? Dammit I'd better get back to work on my family tree homework

Forgive me for any and all ignorance found in this post. I'm only a Junior in highschool. XD


I've actually somewhat formed my own theory for gravity. as for time being relative to gravity? Well, yes and no. Our frame of reference with time is c, the speed of light. Light is affected by gravity, ergo gravity affects time. Except it has to be a seriously dense gravity for it to have much effect on light, such as a black hole (thank you informative stargate episode...). Since it has little to no mass, it's basically our ruler for time. due to it's inability to be affected by anything other than a heavily dense mass gravity. Now that we've established time is based on light, let's look at time travel.

In order to travel back in time, you effectively need to rewind light. God, even thinking about this seriously makes me wonder how people could even think it possible. To travel backwards in time, you'd need to TURN BACK TIME, and since you can't reverse light, you can't reverse time. Even if you COULD, you'd need to do it on a universal scale, because if even one atom is out of place, it wouldn't be your past. It'd be an alternate dimension. Hence the original post about fucking up somebody ELSE's hitler. Even if you DID do all this time travel shit, and you DID kill our hitler... it wouldn't be our hitler anymore. It'd be ANOTHER hitler who died, and OUR timeline would be an alternate where hitler was still alive.

So, yeah. Time travel FTL. Try dimensional travel, and we might be talking.

I know I put "Serious Response" but it actually wasn't one. I was taking a side swipe at everyone here suggesting similar things (and my own ignorance in this field see: here [http://www.escapistmagazine.com/forums/read/7.275642-Physicist-Definitively-Rules-Time-Travel-Impossible?page=3#10692028])

This area of physics is something I really don't understand. I can grasp most of the rest of it but astrophysics melts my brain; psychology is more my speed. Did you know for example that without any external indicators of time (i.e living in an underground bunker/cave) your average human reverts to a 25 hour day? (ranges from 21-27). That is all kinds of messed up when you consider that our planet's day/night cycle is fairly consistent time wise.

I understand the theory about alternate timelines and universes in parallel but thanks for the gravity information. If you want a philosophy question: if you change an alternate universe's history and are resident in that alternate with no present analogue (other you) what makes this universe alternate? To put it another way: how can you be sure the history you came from is the unbroken, unmeddled with "true" course of history?

 

[LCP]

Hahahaha, Impossible...

That word is funny to me...

people will look back at this thread and laugh when we're eating dinosaur burgers

 

[Foxbat Flyer]

I want to time travel... I want to go forward to march next year... for march mayhem and for a 14 day cruise to fiji... but i guess ill have to travel at the speed of earth seconds/minutes/hours/days/weeks/months Owwwww

 

[Will Holmes]

It doesn't rule time travel out at all, it just gives hope for the Many Worlds Theory.

If you go back in time, as soon as you materialise in the past, you've made a little change in the universe that wasn't there before, an impact that will permanently change the future, and will never be the same future that you came from in the first place. If you go further back in time to make changes, the change in how things pan out in the future increases really quickly. That's the Butterfly Effect.

Even if you travel in what you perceive to be a loop and end up at the same point in space and time from your point of view, you won't be in the same universe you started in, and you can never get it back exactly as it was because entropy will kick in and make your actions irreversible.

You can kill Hitler, or teach him to paint better, but the Holocaust would still have happened in your original universe. Actually, it would probably still happen in the universe you landed in as well, but I won't get into that.

 

[fulano]

Yeah, I might have a few things to note:

The guys are using metamaterials, and that's great, but I assume that he's taken as a given that the universe is isotropic and homogenoeous in his model otherwise he'd not be able to use the tools he's using. If that were to not be the case then the whole thing goes out the window.

Let's keep in mind that according to modern findings, and accepting that Dark Matter is a real thing, it would constitute 80% of the matter in the universe, while ordinary matter makes up only 20%. To say the universe is isotropic and homogeneous, considering that, and on top of it say that because of that, plus your theory, time trivel is 100% impossible seems a little out there, if you ask me.

Again, I'm not saying he's wrong, but the fundaments of the assumptions should be noted.

EDITED: because I left out something

 

[Knight Templar]

I am reminded of something I can't quite remember.

"I thought time travel was impossible?"

"Oh no, it's very possible, it just that changing anything creates a logical paradox, so there's not much point and you usually fall into a cave or something and never get found"

"Then how do we change the past?"

"Simple, we go over to a universe almost the same as ours, except it's clock is running a little slow."

 

[Freechoice]

Isn't it basically a requirement that if you travel through time, you're within another dimension? You know, conservation of mass and energy, wot wot?

 

[Kelethor]

This guys a killjoy. Major Killjoy.

 

[Devil's Due]

Anyone who claims to be a scientists but believes in absolutes such as impossibility rather than plausibility are frauds and / or idiots.

There is no way to state something is outright impossible when we have yet to expand to other planets, or galaxies for that matter. Just because something applies here in the Milky Way does not mean it'll apply every where else

 

[aashell13]

Physicists have known that traveling back in time is impossible for quite some time now. This is more of a verification of that and less a new discovery. Time travel forward, on the other hand, is an everyday occurrence

 

[Bara_no_Hime]

[HEADING=1]Dont lose hope![/HEADING]

Science updates theories on a regular basis.

All it will take is some new, previously undetectable something or a mad sub-theory to turn out to be right and it could happen again.

Yeah, seriously.

Wasn't there an article on the Escapist not long ago about a 12 year old disproving the Big Bang Theory?

And doesn't this no-time-travel theory rely on the Big Bang Theory working?

So if the 12 year old kid is right, then time travel is back on the table.

I'm just saying....

 

[Treeinthewoods]

He did a lot of work to find out something I already proved. I promised myself that if I am ever able to travel through time I will journey back to when I was ten and put a note on my nightstand. Since I never found the note I will never be able to travel back in time.

Duh.