So true. A timeline does not need to be straight. It could be a circumference, where anything in the middle is just a radius away from anything that has / is / about to happen.


This pretty much sums it up.

regarding time travelling paradoxes in the first few pages of the thread, how do we know that its not happening now? how do we know that there arent anybody constantly changing our present moment now? How do we know non of the results of the various wars on earth havent been 'fixed' ?

When these changes happen we wouldnt be able to tell right? i'm totally noob in this subject. hope i dont sound too stupid.

Well, that's the problem. We don't.

And so we did not assume.

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This post has been edited by marsalee: Nov 10 2010, 04:53 PM

Time travelling doesnt make sense. What is done cannot be undone. And futures are just possibilities. Life is more complex that you'd think.

Time visits, however, is a different story. But you can only observe.

This post has been edited by teongpeng: Sep 28 2009, 08:13 AM

Some may take science like a religion and here to defend defend and defend so called proven theory, if proven why is it a theory? Similar to the debate of religion and the existence of god using light as the element that thought can travel in time just because of the speed like spirit do. While thinking of the mode of transport, the implication suggests that time can be manipulated as wish and that makes life a joke and purposeless. Imagine going back to the birth of Universe or the end of it, would you go back to where you came from and continue to live?

Preserving a life form of today will make it a primitive specimen in the future, human ethic only permit medical purpose of such technique where a lifetime is a lifetime, who are you to live in the future just because you think you were born in the wrong era? To me, the possibility means the end of the physical world and maybe you are in the spirit world, if there is such a dimension, what are you doing there?

This post has been edited by 3dassets: Sep 28 2009, 02:25 PM

Thinking past is history and now is present and future is not coming yet, this framework obviously restricted the idea of time travel.

Since this is a topic on Time Travel - The Past, Present, and Future, would like to quote the following:

"The distinction between past, present and future is only an illusion, however persistent" - Albert Einstein

His view on time is not time's arrow or the river of time, where time is not flowing through us and every moment we experience now should not be labeled present.

It is merely an event happened in the time medium itself, just like the event happened in the space (x,y,z).

As such, just like we could "go" north, south, east, west (-x, +x), if condition is right, we could "go" in time medium (-t, +t) as time is relative, just like space is relative depending on the observer state.

One needs to put down the past, present, future model and replace it with the elasticity of time to appreciate the idea of time travel.

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Added on October 13, 2009, 2:26 pm
You are referring to casual loop, where past is causally linked to the present. Changing the past is paradoxical, but affecting the past is logically possible, which means that there is no breaking in logic if one event caused another event to occur.

Example, A rich person now rich due to inherited a wealth from a "mystery person" who befriend with his great grandmother 100 years ago. He financed a time machine project now to go back to discover the source of his wealth. At the same time, he bring today news paper to his young great grandmother. With the news paper information on finance, his great grandmother made a fortune out of it, hence this is the source of the rich person wealth.

The rich person was infact the "mystery person" his great grandmother befriend with. Of course later he go back to the future where he stays.

No paradox issue here as the causal loop is self-consistent.

Another example of killing his own ancestor is a paradox as it breaks the cause and effect loop, hence is non-consistent.


This post has been edited by nice.rider: Oct 13 2009, 02:26 PM

Its uncanny that when people think to time travel, they will be drawn to paradoxes. Not to say that we CAN prove it, because the reality we will never know when a paradox occurs. But supposedly to say using time travel to change the past, if we think of time as a book, after umpteen chapters of writing, we remove a supporting character it may not make much of a difference to the reader but supposedly we remove a main character, it would make the book ridiculous so therefore, the writer has 2 options. Continue to read the book, omitting any issue of the erased character wherever he thinks should be included, or write an entirely new book. Therefore it would explain why there are no time travellers visiting us now. Either, they realise that it would not be prudent to go too far back into time to change anything because that would change too many details of the storyline, or only choose to go back a chapter or two where the changes would not be too damaging.
Either way I think the book "the time machine" by H.G. Wells (a good writer btw), has a pretty nice way of explaining time travel.

1)If the light transmitted from our earth need 4 days to reached Mars.
2)A space crew that observe at the earth from mars will have a 4 days delay.(the image of earth he see r 4 days ago,due to light transmitted from earth need 4 days to reached Mars)
3)When a spacecraft travel to Mars in speed of light,the image of our earth tat the spacecrew will c will remain the same/non changing,or wat we said time stopped.
4)But when a spacecraft travel to Mars in a speed tat exceed light speed,the spacecrew will notice things on earth will be moving in backward/like reverse mode on movie,or should i say going back to the past?
5)On the opposite,a spacecraft tat travel back to earth from Mars in light speed/close to light speed,will notice things on earth moving in fastmotion/like fastforward mode in movie,so travel to the future?
6)By the time the spacecraft reached earth,the spacecrew will notice the earth is totally 8 days different from wat he seen from Mars.(the image of earth he c on mars is 4 days ago,when he travel back to earth he need 4 days too even in lightspeed,so 4+4=8 )

Btw,communication signal r not any faster than lightspeed,if we send an email to Mars,the email will need 4 days to reached mars.

if we have the technology to bring one of our (telescope+a video recorder+a crew on it to press the record button) to a faraway place tat r million lightyear away,we might be able record down how dinosaur extinct

This post has been edited by Louiz87: Jan 16 2010, 04:50 PM

Time is just a name for the second u read this tilllllllllllllllllllllllllllllllllllllll this.

So,its impossible to actually travel in time,if we could ever travel faster than speed of light,we'll turn into human spaghetti.

Travel in time,has many meanings

It may means that MrX flew back to 2001 to cease the 911

Or

Your mom adjusted your watch,and so u traveled faster than most of us with 5 seconds or wat.

Or

If every living creature in the world agrees to change today's date to 2009,and it does,then we are still traveling in time ain't it?

No, because the very definition of time is man-made. So if it was a unanimous agreement by the entire world population that we are to suddenly be in year 2030, then what? Time, the travelling of it and other aspects of it are defined by man, and as such are subject to its constraints. In essense, its subjective you know.

Please read the previous posts in the thread.

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This post has been edited by marsalee: Nov 10 2010, 04:53 PM

time travel = teleportation

is that same?

i'm time traveling right now.

I think you just time travel!? I dont mean you literally :-) but your scenario above if if you COULD travel faster than light.

Since the spaceship is traveling with the SoL but our naked eye only be able to see things 4 days later.

You could easily go and do certain thing in Mars and and come back ans say "predict" whats doing to happen and in 4 days it will be true as we see on earth!

There is possibility for time travel, but I think we still have a long way to go to have a breakthru...never say never in science. Once mankind giveup on science we will cease to exist. Our survival was always been on curiosity and to explore.

no one can ever travel in time duh...
only in fiction movies or novels..
it is told..you can nver reach the past...

even if a theory can says that travel in light speed can do it...but..there is no machine can travel in the speed of light....

besides it is only a dream....
i am sure that everyone wants to go to the past or future to change something for their own needs...
but unfortunately..time travel is not theoretically and practically proved...

so..dont ever dreamed to time travel...
tq..

^ this guy is new here, right? =x

Never says never......When you said time travel is not possible, I believe you referred to going back 20 years before and altered the event at that time which impacts the future outcome.

In classical mechanic era, almost everyone by default shared the same view.
Absolute view:
Drama - Nature
Cast - all the atoms, matters
Stage - Space and time

In this classical view, the physicists were tasked to work out the "plot" of this cosmic drama within the absolute entity of space and time or to analysis the cast who plays on the stage.
The centric or core of this "stage" idea is that there is an unidirectional of the arrow of time that the casts are playing throughout the entire cosmic drama.

It took Einstein to challenge this very conceptual foundation of the absolute entity of space and time.
Relativity view:
Drama - Nature
Cast - all the atoms, matters, space and time

The stage is not like what is defined earlier in classical view, there is "no stage", and space and time are part of the cast. What does this means?

Space and time play a full and active role in the drama. They are not simply there as an unchanging, absolute entity of nature, ie the "stage"; they are physical things, changeable, and subject to physical law.

A physical thing (space and time in this case) which is subjected to physical law, means they are subjected to alteration and modification pending on the external factors that influence them.
Can we go to +t or -t if we were in the right condition? Think again...............

P/S: In this cosmic drama, "by default", one will ask if "an intelligent director" exists who decide how the drama start, ie "the begining" and how he influences the "play" and how he would like the drama end. This became an determinism and free will arguments, and has been pretty much covered under different topics altogether.

i hope this is impossible,
cause if there is something like time travel
i think no one will treasure what they have now