Time is both infinite and finite – we have an estimate of the age of the universe (about 12 to 15 billion years, which has been refined down from that wide range in recent times from the earlier 9 to 22 billion years). To put it in context the estimated age of our earth is a bit more than the current range of error in the age of the universe (about 4 billion years). It is predicted that our Milky Way Galaxy will collide with the Andromeda Galaxy in about 10 billion years – and that may result in disruptions that may destroy our earth – but then again, depending on which galaxy takes dominance, it may not.
Time and space are a continuum, according to Einstein. Others have modified that a bit. No theoretical physicist can ever be correct, he can only approximate the conditions of the universe through theory – and the practical physicist can only find ways to confirm or deny the “working hypothesis” (as Hubble did for Einstein).
If time and space are a continuum, and Wheeler’s black holes and singularities are real, then all sorts of Star Trek things might be possible. UFOs from a distance through warp drive, megneto/gravito devices that warp the continuum. But I’m afraid there is a problem there. These all work at molecular or atomic levels – and we as human beings are a complex combination of organized molecules. And I have to assume the proposed aliens would be also (even if silicon based from a different atmosphere).
The current speculation (recent Scientific American) on alternative universes falls into the same trap. Their existance may be real, but our ability to penetrate them is limited by our corporeal status.
Infinity is an impossible perception for us – we can conceive it mathematically (and Cantor even proposed, and proved, an infinity beyond infinity). We can pontificate on the equality of the integers and the rational numbers, even though they each go on forever and can’t be mapped within a range. But when it comes to philsophical time – the infinity of time and space, but yet the finiteness of the closed universe in space – and the finiteness of the apparently discovered beginning of time with the Big Bang – the mind boggles. Some seek God (and some already knew He was there – and don’t really think of space and time). Others, like myself, find it both mind boggling and fascinating. Conflicting “truths”, the truth of infinity and the truth of an initial Big Bang. Einstein was once asked (probably apochryphal) “if the universe is closed then what is beyond it”. “Nothing, not even space”.
Our lives are finite, or infinite if we are believers in any of many gods. Our ability to perceive the infinite is limited by our selves, although our minds can conceive of it. The Theists solve the problem by postulating God, the Atheists duck the problem by ignoring the void – those like myself who recognize the impossibilities just relax and enjoy life.
Isaiah Berlin spoke of a dichotomy of people, the foxes and the badgers. The fox sees the complexities of the world and glories in it – the badger builds his burrow and protects himself from it. The militant Atheist sees himself as a fox, but he is actually a badger who rejects the complexity. I’ll not discuss the religious, they have been discussed enough by others.
I’ll not compliment myself by calling myself a fox, I’ll just relax and hope the religious are right – eternal life wouldn’t be the worst thing that could happen.