What a time machine means? cant we build it?
541554
I know i ain't no gonna be the best answer but isn't this spamming?!?!
248955
I don't think it is possible, and if so the experiment itself would probably detroy the fabric of our reality to the point that people's answers would disappear, and reappear as different answers. The time machine does make for some fine fiction, though.
12025
no, because time is only a mesurement that we humans have come up with.  if anything, you can't travel through time because there are an infinite number of universes constantly being created.
1119002
Time folds in as much as it is within life.\nThe future exists with the past
418249
no...the past cannot be revisited.It is scientifically impossible to redo realtime...time is not a program we can go back and fix.\nReligously,it is not even thought of....
720083
well its theoretically feasible to go forward in time but not backwards, but with today's technology its not very doable.
381508
Think about what time traveling to the past means. It means that the entire universe except the time traveler is in a previous state. Now, for the time traveler, his time is still moving forward. He is older in the past after his journey than he was before his journey. \n\nSo, you have an entire universe one way and our traveler another. Since there was no past that existed that had his time traveler self in it, where has he gone? What is more reasonable is a time traveler experiment you can do yourself  by sending a smaller part of the universe into the past and watching that as you move foreward. Sound weird? Well, you can do it by resetting your computer. It goes into a past state and you keep moving foreward. This sort of time travel sounds like a cop out but it is just what is generally described on a smaller scale. That is, the entire universe but the traveler gets re-set to a previous condition.\n\nI know this answer doesn't satisfy the mystery feeling one gets with the time traveling notion, but it's what we really mean.
326685
Once i invent a time machine, i'll contact you and take you with me. You'll get your answer then.
584068
Who knows? To be honest, no-one will ever know, barring the invention of a (theoretically impossible) time machine. It's a matter of personal belief.
1045387
GOOD QUESTION: well done! There is not really any such thing as time, it is merely our way of describing a particular abstract concept. If it was a solid physical reality it surely couldn't be relative. Lets all go and read Einstein and try to figure it out!
1156487
The accurate answer to your second question is "not really".  Our current system for measuring time is based on the movements of our planet & our solar system, which of course did not exist in their current state at the beginning.  Those units, however, have been standardized for convenience & accuracy to reference the cesium atom, so can be back-calculated.\n\nThe answer to your first question is that time began at the instant of the so-called 'big bang'.  Before that there was nothing to reference it again, so the passage of time had no meaning or substance.\n\nWeird, huh?
601936
I believe that true time is simply another dimension we just haven't figured out how to move in any but one direction. Time as in seconds, minutes, etc are nothing but a random measurement we have placed on that axis; more random than how we chose inches, feet, or meters for the other axis'.
186420
Time travel seems to make sense to us because we have the concepts of past and future.  In particular, we can vividly picture in our minds the parts of the past we have experienced.  The past can seem to have a kind of reality because of memory, as the can future because of imagination.  But, neither the past nor the future have any real existence.  There is only the present.\n\nTime is not a container like space is.  We can travel in space because other places really exist.  Time is not a container.  There's nowhere to go.  So, no, time travel is not possible.
964513
A time machine.\n\nI have always been fascinated with the concept of time travel, changing the past and seeing the future.  \n\nActually, I think most people are. \n\nMost have thought "What if" I could go back in time and rearrange a key event in their past or in history. \n\nThe future, of course, would just be fun to gaze on.  So many things have changed in the last 100 years, it's difficult to imagine where we might be in another 1000 years...if we don't destroy ourselves.\n\n...but even that would be fascinating to see:\n\n"The day the earth died".
18909
Time is just a concept, it does not really exist. We track time by the movement of celestial objects in the universe and light but time is abstract.
803113
Time- and who knows where it goes- don't know where it came from- D
590908
Without going into detail I don't claim to understand, I have read that time travel to the past is theoretically possible, but not with today's technology, so yes, I allow for the possiblity. Many of yesterday's theories are now today's scientific facts.\n\nFurthermore, UFO means "unidentified" flying object. Every year, there is a small fraction of aerial phenomena which cannot be identified or explained - making them "unidentified". These occurrences may not be inhabited extre-terrestrial spacecraft (or they may), but to say there are no "UFOs" is fallacious.