if someone went back in time to recover a missing object, wouldnt that mean they already have it in their possesion? And woulndnt the object they were looking for not be there?

I like to think of time as a river. You're a particle floating down the river. Pick you up and move you upstream, and you'll still pass through the same moments in time, but you won't affect the water you used to be in. Cut the whole river off with a dam, and all the water downstream of the dam continues to flow (please, no one talk about turbulence and fluid dynamics, you'll ruin the illustration).

Go back in time and change something -- you'll change it for you and everyone else that exists at the same time as you, but for those in the timeframe you came from there will be no change, except that at some point in time you disappeared.

The most effective way to clone yourself from your own perspective is to go back in time a few seconds and then stop yourself from going back in time again. Voila! There are two of you! But at the cost of your existence in the time-frame you originally left -- you can't say to someone "Watch, I'll clone myself!" As they'll see you leave their timeframe and never come back.

Well, if time travel was to happen that's how I would imagine it.

Jibb

if you "travel back" in time,
you will not have the actual "past".

Because you have not been exactly there in the past.
So it is not your actual past, but some new state
that resembles your past.

There is simply no way to travel back in time.

Maybe some way to recreate a past state to a certain degree.
(like repositioning billiard-ball to a past position)
Even if everything looks like in the past, it is
not an actual tryvelling into the past.

Since in the past you did not know you where in the
future, you can never "BE" in the past with memories about
beeing in the future before.

There are a few different theories around.

But I believe if you look at it logically, you can only
ever end up with the "fixed event" theory.
(thats what I call it, as I dont know its official name)
The past has already happened and is therefore 'fixed', so it cant be 'changed'.
Anything you do in the past has already happened,even if there is no record of it in the future.

So, using your example, yes you can travel back in time to recover a lost object.
But in turn, YOU may be the reason it was lost. Because the 'future' you took it away.
And during the time it was "lost", it wasnt anyWHERE, because it was someWHEN else.

Unless of course the 'future' you stays in the past, in which case, "he" has it, not the 'past' you.

And, of course, the 'future' you will never give the object to the 'past' you
for an unknown reason... Because if he did, then the 'future' you would have
no reason to go back, and therefore was never there to hand it over, an so would
then need to travel back from the future cause its missing again.....
Bzzzzt.... CLICK.... Ping! Paradox Achieved. Thats the unknown reason.


Yes it IS tricky, keeping all the pre- current- and past- tenses in mind,
but you can see the underlying logic.

The whole problem with any type of "timeparadox" questions,
is, that
the first analysis must be:
How should it be possible to turn back time?

If this can not be answered, the following
analysis is not valid, as it
might ignore mechanics of the nessecary first analysis.

Traveling back in time is impossible. Period.

ppl say time is a device created by humans to measure the past present and future.So the past could really just be recorded memories.Maybe the past doesnt physicly exist to where ppl can go back and change it.Maybe its all just memerories.Theres too many paradox type scenario's for time travel to be possible.

Is travelling back in time possible when you first leap forward, and then return back to where you left? Like, when you first invent a time machine, you are then able to store the current date, and that's as early back as you can go...

restoring/changing/altering or actually being there is indeed impossible. But all that data is not lost. I mean altough you cannot travel back in time, you can still see that data, if you knew how to use it.(i mean non-pre recorded camera.)

another thing is that you know that things like about hearing the sound of the lightings a bit later or like when you look at the sky you dont see the actual place of the sun but you see where it was 8 mins ago... then if we could travel faster than light, we do something and get into that device and travel somewhere and when you look back, you should be seeing yourself doing what you just did.

Hehe, the place of the sun? Are you sure?
You do see what the sun looked like 8 minutes ago, but not its place. It's not the sun turning around us!

That said, theoretically a hole in time and space can travel you back and forth in time. I've been reading some time ago something about using a rotating gravitational field that you could theoretically use to move back and forth in time. But this is entirely based on fragments of memory from my mind. Not quite a stable source.