Time Travel???

What is possible, then?

Events are possible only if they are consistent with everything in the timespace.

time
hello, I just dropped by these boards and seen this interesting topic and I wondered if you would mind if I told you what came to me when I thought on this question you have raised here.

could it be that time is the expansion of space and that is why it is relative to Gravity and velocity? If that were true then this particular time is a position in an expanding field and so could never be returned to. It would mean that time passage would differ on different bodies in space according to their mass, their gravity slowing the local expansion and in the case of travel near the speed of light, it would be the hubble constant which would be the relevant velocity but any velocity would have it's affect.

but these are just the musings of a curious little monkey

Satt, but why would it be impossible? What is there to prevent that from happening?

going back,
I think that if it were possible to go back in time you wouldn't find it as it was. I think that if time were like a river and you could paddle against the current to get back to where you came from that would be the way we imagine time travel usually, everything is the same as it once was.

But, I don't think it's like that, I think it's more like a river which flows but so does the banks and the riverbed and the fields and the sky's above and everything that there is, all flowing along and moving and changing and if you could paddle back down the river that you were in you wouldn't recognize the scenery when you got back to the place in time you were looking for,because now there would be new events, new fields and sky's occupying that space. that's just what I think though.

c.g.

Human knowledge is not formed to allow for inconsistencies. And "time" is a part of human knowledge.

You might find out that the man your mother married wasn't your father, for one thing..

LOL Stillwater.

stillwater, then why do u exist as the current you? your dna and genetic makeup would not be the same anymore

HI!

One of the scenarios I like the most is the one from
the Hitchicker's Guide book: time travel machine was impossible
to invent, so the folks in the future just sent it back in time
with instructions on how to build it - and there in the past
scientists used this info to build one. So the folks in the future
could send it back..

I think therein lies the great mistery of time :wink:

Relative

Axon, welcome; just a couple of thoughts:

time is merely the 'relationship' of masses in the universe; think of it as a scale, not an entity.

going back in time could be possible (as you know 100 years ago scientific wisdom pointed out that heavier than air flight was impossible!); and the reason that it wouldn't be noticed is that the changes caused by such an event would be imposed on the universe instantly, and would include the content of your perceptions and memory, so that no evidence of the 'pre-event' status would ever be apparent (rather like the Men in Black's little 'flash pen' effect!). A further analogy would be the save function on your computer overwriting a new itteration over the old with no residual evidence of 'before'.

and if and when the 'time machine' is invented, the hydrogen bomb is going to look like a child's toy in comparison to the devastation that could be wrought1

Re: Time Travel???

The second law of thermodynamics is asymmetric in time. Looks like factual essence to me.

I read about other 'time arrows' - but can't remember any.. other than the fact that we remember the past and not the future.
But they only break the symmetry of time, they do not say what time is, or that time travel is impossible..
I think some results of General Relativity indicated there is a possibility called 'White holes' or 'Wormholes' in it that permit time travel.

But I agree time is real - I mean it would be difficult to ignore.

Not sure I understand this idea.

I'm not sure what point you are trying to make here. Yes, I obviously exist as an entity, moving through time. Processes that occur in a linear fashion occur (for example, I cut myself and then it heals, I do not develop scar tissue now to deal with an injury I may suffer next year) and I perceptively age from infant to an elderly man.

To the best of my knowledge this is not a result of my genetic make-up. That only provides the plans and processes to 'build' a fully functioning, fertile member of my species. If I made a journey through time to 'meet' myself, unless the process involved some sort of realignment of my cells or molecules, we'd only be two functioning human beings with identical genetic information.