"FTL Yes or No" Topic

Ok some dumb??? questions if you go FTL you time travel?

If time travel is possible then there must be multi time lines.

As with time travel one time line would be impossible too many paradoxes.

Therefore if you travelled FTL you could not return to your time line.

With wormholes, space strings and warp if you have travelled FTL back to Q1 you must of time travelled.

I see time travel as the province of "gods". Once you can do it, you are godlike, because you can see all history, past and "future" (not your future, of course, only relative to a position leading up to the furthest extent of the universe's light spectrum record), simply by "traveling" to the place where it is recorded in the light record. Forward or backward along the light spectrum, makes no difference to a godlike traveler.

Now, what "technology" would allow entry or penetration into the "recorded" light spectrum? It would be one thing to observe, quite another to "join" with the recorded events…………..

Everyone and everything travels in time. Forward.
Other than that, it's the province of science fiction. The "Gotcha!" kind where the reader is looking for logical fallacies.
When it happens on a tv show, it's a sign of lazy writing and that the show has jumped the shark.

Who could have known that Faster-than-light travel could be so complicated?

Star Trek OS jumped the shark a couple of times at least. And the movies followed in the same lazy vein. I never liked the time travel plots. And other than enjoying Tom Baker, I've never been a Dr Who fan………….

if you go FTL you time travel?

Depends on how it is accomplished.

If time travel is possible then there must be multi time lines.

No. The type of time travel based on general relativity and warping of space breaks the causality chain, so you don't need multi timelines since there are no paradoxes.

The most important thing to understand about time travel is that there is no such thing as time. It's just a placeholder concept to help us characterize change.

Ok I go back in time and kill Hitler when he is 20 years old. Hitler is dead. So back to NOW why would I kill Hitler he never came to power how do I know to go back to kill him.

The most important thing to understand about time travel is that there is no such thing as time.

Its part of the space-time continuum.

"The views of space and time which I wish to lay before you have sprung from the soil of experimental physics, and therein lies their strength. They are radical. henceforth, space by itself, and time by itself, are doomed to fade away into mere shadows, and only a kind of union of the two will preserve an independent reality."

A Einstein

link

@jah: if there is anything to "time travel" then there is something to the multiverse, where an event "splits off" into a separated "time frame". If time travel is possible, it can only prove the multiverse…………

Everyone and everything travels in time. Forward.

Yes, but time dilates the faster one travels. Even atomic clocks on jets going around the world have time going slower than with stationary clocks.

link

So the closer to C the more time slows down. At C time stops. So for theoretical FTL particles like tachyons does time go backwards? Possibly.

Other than that, it's the province of science fiction.

Yep.

Who could have known that Faster-than-light travel could be so complicated?

Lol!

When it happens on a tv show, it's a sign of lazy writing and that the show has jumped the shark.

Some gentlemen are here who would like a word with you.

Ron

A short video on time travel, according to the educated people, its possible.

YouTube link

And then the science of Dr. Who.
YouTube link

If your motivation to go back in time is to kill Hitler, then you may very well go back in time; you just won't succeed in killing Hitler, because Hitler was not killed. That isn't to say that the past can't be affected by a time traveler, just that the time traveler's actions in the past will have already happened before the time traveler ever goes back in time, or even finds the motivation to do so. In short, Bradbury was wrong; there is no butterfly effect, nor is there ever a time paradox. The causality of events will not be altered; everything in the past, even the actions of time travelers, is already done. There is no need for any multiverse, or alternate time lines, or anything of the sort; that's all fiction. "The moving finger writes; and, having writ, moves on; nor all thy piety nor wit shall lure it back to cancel half a line; nor all thy tears wash out a word of it."

For an excellent treatment of this idea (and just a fun read), I point you to Robert Heinlein's classic The Door Into Summer.

By the way, I also don't think that travelling faster than light necessarily entails travelling faster than time, but rather faster than the perception of time with regards to both the point of origin and the destination.

Consider if I take a warp ship from here to Alpha Centauri. Let's assume that the ship is fast enough to measure the journey in months rather than years. So I arrive at Alpha Centauri in around 4 months, nearly 3 years and 8 months prior to the light of my departure. I can see myself leave! However, that seeing myself leave is merely a glimpse into my past, not my past itself, just as the light from the Sun on reaching the Earth is the light of the Sun's past (eight hours previous), not the Sun's current state. My trip still took time— four months of it, for me. And while yes, on Earth, the light of my arrival will not be seen for 4 years and 4 months, that does not mean that I will have arrived some 4 years and 4 months after my departure; it just means that Earth is only then receiving the notification. Similarly, if I turn around and return to Earth immediately upon arrival at AC, my entire trip will take 8 months, for both me and Earth, and though I will show up before I can be seen to either arrive at AC or leave AC, I have not travelled back in time by any logical argument.
The catch, of course, is time dilation caused by acceleration; however, if I am using a warp bubble as described in a previous thread (moving spacetime itself rather than merely matter), then I don't think such dilation would ever occur, rendering consideration of it moot.

On a side note, while it's probable a space warping technique might be visible to an outside observer due to gravitational lensing on light sources in a direct line to the observer with the ship's travel intersecting that line, any other as yet unknown to us form of FTL would likely be completely unobservable through any conventional means. So FTL craft could be zipping through our little corner of the Galaxy, and we'd never ever see them unless they stopped to have a look around themselves.

Oh, and I think people just like to say that time travel stories in science fiction shows are bad because for some reason it's currently trendy and superior-sounding to say so. For me, I often find time travel episodes to be among the more cleverly written ones. Not saying there aren't bad ones, just that the bad ones are usually bad because the writing itself is bad, not because of time travel as a plot point.

Take Star Trek. It's acknowledged almost universally that the best episode of the original series is "The City on the Edge of Forever", which is a time travel episode! Similarly, "Yesterday's Enterprise," oft acclaimed best episode of ST:TNG is about time travel. Ditto ST:DS9's "Trials and Tribulations," Voyager's two part "Year of Hell" (quite good, even if you hate the show). And in a different vein, I happen to love the Castle sixth season episode "Time Will Tell," which delightfully mocks Terminator (and features some great TV SciFi actors in cameo roles, too).

So, no, time travel DOES NOT equal "bad TV." Bad TV equals Bad TV; time travel just gets sucked up into it, along with any other otherwise good ideas that bad tv writers latch onto as a gimmick to save their failing efforts. It's not the plot that's the problem, it's the plotter.

By the way, I also don't think that travelling faster than light necessarily entails travelling faster than time,….

But that's not what's being proposed. Just what does "traveling faster than time" mean? Luckily, it doesn't matter.
As speed of an object increases, it's relative passing of time slows down. Time ceases to exist for a photon particle. What happens to an (admittedly theoretical) tachyon?

The consensus is that the only way for time travel in to the past to be possible is multi timelines/multi verses . Einstein stated that time was not fixed and nobody of note has proved otherwise. I do not agree with you on fixed time the only way that is possible is that we have no free will and everything is preordained. Regardless of the method FTL will affect you and not the rest of the universe it will continue on. What I am looking for is if it is possible to travel FTL and return to your own timeline.

Well, if you think about it, you realize that every action is determined by the conditions present at the time of the action (ALL of the conditions). For example, take the roll of a die. It appears random to us, but in fact the results of the die are determined by all the factors in place when the die is dropped; its angle, spin, internal molecular structure, the molecular state of the air it passes through, not to mention temperature and pressure, any air currents, the height of the fall, the specific gravitational conditions of the point where the die is dropped, however minutely different (or not), even the molecular makeup, shape, texture, etc. of the surface the die strikes and rolls along… If you could know ALL of these, every minute detail, then you could, in theory, predict the final outcome of the roll with absolute certainty. So, too, for all other occurences, even those that involve "choice."

BUt that does not mean that free choice is not a factor, or that even a set past defines the current choice. A set past does not define the future any more than looking down at a table determines the path of an ant crossing it. All it defines is the choices that have already occurred, though these choices were made freely in the time they were made. Even time travel into the past would be incorporated into these choices. It's not that time is indelibly set to begin with, it's just that events which we know to have occurred will have occurred, and no choice in the future made by any time traveler will change that because they didn't change that. You are therefore fully free in the future to TRY to go back in time and kill Hitler, but you won't succeed in one or certainly the other, no matter how you plan it. It's not that time is protecting itself, it's just that it didn't happen, QED. Which you now know, so maybe it's best not to try, after all.

faster than time

Mea culpa; poor choice of words on my part. I should have just said "time travel." And since the tachyon is entirely theoretical, we actually don't know what happens to an object travelling faster than light as regards to time.

As speed of an object increases, its relative passing of time slows down.

Yep. "Speed of an object increases…" Meaning mass (AKA matter) under acceleration. But our theoretical warp drive never accelerates ANY object, much less any matter. It just carries the object along as SPACETIME "ripples" through itself. So I'm saying no time dilation may occur AT ALL since it's not the matter that's moving, but the bubble of spacetime around it. If that's the case, then an FTL warp drive is not a time travel device at all, but just a way to beat light to wherever we want to go and hopefully arrive in time for dinner.