There is a classic bit on a Cheech and Chong album where a hustler asks a hippie, “Hey, wanna buy a watch?” To which the hippie replies, “Aah – no thanks, man. I’m not into time.”
Which is less prosaic than it sounds. The thing is: time does not EXIST – there is only NOW.
Oh sure, try telling your boss that when you roll in ten minutes late for work. But actually, from everything we know, it is TRUE.
A look at time travel tells us this – the concept of travelling to the past and future. Except we ALL travel to the future on a regular basis. Every night, we go to sleep and when we wake – voila! It is the next day.
And if scientists ever manage to iron the wrinkles out of cryogenic suspension technology, it will be possible to “hibernate” for a century – or a millennium.
The trick is coming BACK.
When people talk of travelling in time to the FUTURE, they are assuming it will then be possible to RETURN. But to do THAT, would involve travelling BACK in time – and that is just NOT POSSIBLE.
There are many paradoxes involved – go back and kill Hitler and when you return, everything will be different. You might not EXIST. Or go back and stop your parents meeting and you DEFINITELY will not exist. So in either case, how could you have gone back in time in the first place?
Actually, the best one is the causal loop. This is where you go back and change something – only to return to the present to discover nothing has changed. Then you go back again and discover your last action MADE the present happen. But how…?
And so on.
Of course, SEEING back in time is fine: you merely change the PRESENT, by gaining a fuller understanding of the past – which remains unchanged.
Thus we ALL visit the past every day – but only because light takes time to travel. F’rinstance, when you observe the Moon, you are seeing it as it was about one point three seconds ago – the Sun, around eight point three minutes – and the stars, YEARS ago.
Even talking to someone face to face, you are seeing them as they were, some three pico-seconds ago. Of course, SOUND only travels at 750-odd MPH – so you are HEARING them with merely a three milli-second delay.
They are OUT OF SYNCH – just not enough to for you to detect!
But all of that is just a trick of the light (and sound). It is travelling PHYSICALLY back in time that causes the chronoclasms.
Even if you materialised in the middle of a desert, hundreds of miles from people, animals, even insects – you would still be CHANGING the past, simply by displacing AIR.
The fact is, the past has HAPPENED. You CANNOT change it.
We all live in the PRESENT. We have free choice about what to do in it and while our actions may change the FUTURE – for better or worse – the past is done and dusted.
It may have shaped our present, but otherwise it is irrelevant.
As stated above, there is only NOW – so eat, drink and be merry!
Note: one can still have fun with FANTASISING about travelling back in time – for an example, hit http://maxtimetraveller.wordpress.com/