h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

And it definitely moves faster as one gets older. Verified unanimously by every person I've ever asked.

Whilst I am completely ignorant of physics, beyond school boy knowledge and the half truths that are taught there because the 'truth' is too complicated for young minds, I have enjoyed following this conversation on the nature of the Universe and time and hopefully will continue to do so. Bearing that in mind forgive me my ignorance and, if you can, give me an idiot's answer to my question:

Does time exist if its passage is not observed?

Your question, my friend (as I'm sure you well know), is deeply profound. It strikes to the very heart of metaphysical enquiry. Traditionally, I suppose you could say that there are two camps. It comes down to those who believe that the universe is objective and can exist quite happily without the presence of a conscious observer, and those who believe that the universe is subjective and ONLY exists in the presence of a conscious observer. Objective or Subjective? You take your choice.

I believe that the answer to your question is far more subtle. Indeed, I don't believe there is a rational answer, for just as surely as the personal is embodied within the universal, the universal is embodied within the personal. The personal and the universal, subject and object, are recursively engaged in a mystical symbiosis. The whole is composed of parts, but those parts are composed by the whole. We and the universe exist as one unbroken, unbreakable epistemic circuit.

I doubt whether this is the kind of answer you were looking for, but at least there's no physics! Glad you've been enjoying the conversation.

My dear Serendipity, the kind of answer I was looking for was one which did *not* consist of complicated mathematical formulae or reference to obscure physics theories, and you have ably satisfied that implied requirement. Not only that, I am sympathetic to your answer and its subtlety. I will consider this further...

Sorry for the delay, a single ISDN line split 16 ways doesn't give fast net access.

I deliberately said time 'appears to be' unidirectional to avoid this debate, since wormholes and other esoteric physics allow time travel in theory (I'm writing a 5000 word essay to win a £500 prize from Cambridge university on this topic). Is there anything which we definately know, or failing that, believe is NOT quantised? So far, time, charge (even if in 1/3rds), space and loads of other things are... is it truly digital?

I believe that space AND time ARE expanding..as in 'spacetime',but
the conversion factor of 1/300,000,000 (as in metres per second)
tends to dilute the effect of this.
Time is in effect expanding at a rate of one second per second 8^D.
If the expansion of the universe were to stop,perhaps so would time,
and if it started to contract..time may run sdrawkcab....
I really think that spacetime is very 'flat',with insufficient mass
to cause a collapse,this because of the inflationary period in the
very early universe.

The point you make is very interesting. Your understanding of the expansion of time seems to be one derived directly from the interrelationship of space and time, but I think it exposes the very kind of problems that are normally glossed over with the standard theory. You suggest that an expansion in space implies an expansion in time because the two are effectively inter-convertible, but this would seem to imply that the expansion of space does indeed change the laws of physics - even if the effect is very small - which does not seem to happen. This is my big question: how does spacetime expand WITHOUT changing the laws of physics, unless the expansion is a scale expansion?. The inflationary scenario only has space expanding in the absence of matter, between galaxies, but I believe this assumption needs to be questioned. My main point is that we don't really know how to interpret the meaning of the various solutions to Einstein's General Relativity equation, and therefore we should remain open to other possibilities of interpretation besides the Big Bang model. One can easily be led to believe that physicists have solved the big cosmological questions. I just think that there is much more uncertainty than is acknowledged, and even if I supported the Big Bang theory, I would still like to see more debate than there is right now.

At one representational level I do believe we can say the universe is digital. But there is another level where continuity rules over discreteness. This is the realm of wholeness. As I have said before, the whole is composed of parts (rational, digital), but those parts are composed by the whole (intuitive, mystical). I think we have to be very wary of thinking that the universe can be described purely in a digital way. I believe that to be a gross simplification.

Serendipity,
I've always thought of time as a field, much like gravity, which doesn't move at all. Rather, we move through it, and percieve our movement as the movement of time.
Our perceptions seem to create the reality we wish to percieve. Just as we look at vast empty spaces with tiny particals bopping about in their dance of attraction/repulsion and percieve physical objects, so do we look at our directional development and project our movement as the movement of time.
But then, I do tend to percieve things a bit oddly.
Love is the law,
Mordek 93

Time as a field? Certainly an interesting idea that needs further consideration.
As regards completeness vs. digital, the interest in digital is on the 'Massive Universe-wide MUD' idea [ie: the entire universe is a multiuser simulation]. I wonder how long at the current increase in processor power it would take to simulate the world?

The Cow,
Sooner than you think. The work on AI right now is getting much closer to an S/R mechanism/life-form than most people realise.
Love is the law,
Mordek93

Sorry, what's S/R? Self-realising? Replicating? If it's replicating it reminds me of 'Batteries not Included'!

Love is the law.
The reference was to stimulus/response mecanisms (much like human beings) that are being rapidly realised by the researchers into AI.
Interestingly, Artificial Intelligence will probably first be realised into bodies that are much like Lego blocks in their construction.
Love under will,
Mordek93