The real problem is time.

[ollypenrice]

We need a better theory of time. The idea of a past. present and future, with the present advancing into the future and leaving more past behind, is fine in everyday life. It's clearly wrong, though. Or at least it is incomplete. It doesn't seem to work at the quantum scale and it leaves us stuck for what to say about the Big Bang. I don't like the phrase 'before' the big bang and think 'outside' would be better. The majestic

Feynman pointed out that you can never distinguish between an electron and a positron moving backwards through time. They seem to be the same thing.

Aha... we are onto something, but what??

Olly.

[EA2007]

I am just waiting for.................

"on the third stroke of the time sponsored by accurist it will be 'no-one really knows'"

[thing]

I'm rather drawn to the conclusion that time is a mental construct, it doesn't really exist. Past present and future are already there, there is only the now.

[lunator]

I'm rather drawn to the conclusion that time is a mental construct, it doesn't really exist. Past present and future are already there, there is only the now.

So what you are saying is 6 year olds have it right as they only live in the now

[SteveL]

Olly, step away from the wine...

[acey]

We need a better theory of time.

I totally agree, Olly. For some alternatives try:

Time is subjective (H. Bergson, early 20th cent philosopher)

Time does not exist (McTaggart, early 20th cent philosopher)

There is not one time dimension but an infinite number (JW Dunne, aero-engineer and fly fisher)

Time is the moving image of eternity (Plato)

Time is circular (Godel - mathematician and paranoic)

Time does not exist (Julian Barbour, physicist, The End Of Time - fascinating book)

There are plenty more of course but try googling some of these guys for starters.

Another book I really liked - Time's Arrow by Huw Price (considers eg time is entropy - Boltzmann).

Andrew

[ollypenrice]

Thanks Andrew, when my mind has recovered from Michael Lockwood's Labyrinth of Time I will give some of those a try. I was a little disturbed when a rather clever chap from Astronomy Now flipped through my copy and seemed to find it light and entertaining. I waded through at two pages per day!!

Wine, Steve? Me? Can't afford it. You have a to pay a euro a litre for the good stuff down here...

Cheers (whoops)

Olly.

[thing]

I'm rather drawn to the conclusion that time is a mental construct, it doesn't really exist. Past present and future are already there, there is only the now.

So what you are saying is 6 year olds have it right as they only live in the now

There's something to be said for that actually.

[acey]

Feynman pointed out that you can never distinguish between an electron and a positron moving backwards through time. They seem to be the same thing.

Feynman and Wheeler noted that you might therefore suppose that all the electrons and positrons in the universe are really a single particle whose world-line is like a tangled thread - each "now" corresponds to a horizontal slice through the tangle, which the thread meets in a great many points. Problem with this idea is that it predicts an equal number of positrons and electrons, which we don't see. But it does bring in yet another theory of time - the "block universe".

Related to this, Wheeler and Feynman developed the "absorber theory" of radiation, the idea being that light goes both forwards and backwards in time (as James Clerk Maxwell actually predicted but thought nuts). The backwards moving light should cancel with forward-moving light, which is why we don't see light converging on light bulbs etc. Attempts were made to find some residual backwards-moving light - but failed, so this was another of their theories that fell by the wayside.

It's nicely explained in Paul Davies's book "About Time".

[ollypenrice]

I must read this one. To challenge Dave's point that he he doesn't belive in past or future but only in 'now' ... well doesn't 'now' need past and future to define it? What, in the absence of past and future, does 'now' mean?

However, no, I think a sound point remains. I might not want to call it 'now' but I suspect we are somehow embedded in something that just 'is.'

The philosophers I have read seem to feel that if you lose past, present and future, you lose free will. I don't know if I buy this. To stick with the language we know, maybe the future 'already knows' what we decided.

A clear sky and a cloudy mind. Ah well...

Olly.

[timetraveller]

I don't look at time in terms of hours minutes and seconds those are just man made divisions that are used to assist in the division of what are endless rhythms or natural occurring cycles I preffer to look at time as a series of natural vibrations or wavelengths created by the energy locked up inside all matter and that the various electromagnetic wavelengths are present from DC to light and that all of these different frequencies interact with each other to create a continuum so instead of saying it takes 8 minutes for sun light to reach Earth it would be more accurate to say that it takes x number of wavelengths to reach from one set point to another

[Tiny]

As a three dimensional person wandering along a timeline it does not really affect me if everything is set in stone or if it just makes itself up as it goes along. As far as I am concerned I only observe it when (or rather just after) it happens.

Having said that....I might expect, given a set of constraints for something to happen in the next few minutes time - but life tends to spring surprises. (Like the post arriving just at the moment I wrote the word surprises and me stopping to read and react to it.)

Knowing the future might be interesting but would you like to know when you would die and how? Better to let that stay as an unknown in the future maybe.

[Rosanella]

I'm rather drawn to the conclusion that time is a mental construct, it doesn't really exist. Past present and future are already there, there is only the now.

I too believe that time does not exist at all. It is just a modus of reference indicating the passing of events that the human mind needs to refer to, facilitating (or so we think) our day-to-day occurrences. There is not Time, there is only the Continuum (in my opinion).

[Tiny]

Certainly I think we use time and expect things to be in such a state at such a time of day.

Often on the boat I used to change all the clocks so 5am was 7am. Magically those who didn't know happily got up at 5 rather than 7 and worked the day to that clock. As we had little contact with the outside world this worked perfectly until some bloke asked mother the time and we had to correct her when he started panicing about loosing hours out of his life. At that point mother gave a huge lecture on how she really knew and refused to operate on the revised time scale when it was time to get up next day as she could not stand to get up so early. The fact she had when she thought the clocks was right and not two hours fast showed how dependent she (and maybe we all) are on what the clock says.

It is interesting that before clocks were widespread the early civizations divided day into 12 hours and night into twelve - no matter that the two periods really were different lengths on all but a couple of days of the year. It worked OK for them showing time is more an agreed state of mind than a constant when good old man gets on the job.

[supernova]

I'm rather drawn to the conclusion that time is a mental construct, it doesn't really exist. Past present and future are already there, there is only the now.

I too believe that time does not exist at all. It is just a modus of reference indicating the passing of events that the human mind needs to refer to, facilitating (or so we think) our day-to-day occurrences. There is not Time, there is only the Continuum (in my opinion).

Very well put, I have allways had a problem with this Time thing.

If nothing moved or happend then there would be no time.

[acey]

If nothing moved or happend then there would be no time.

Everything's happening and there's no time!

[Tiny]

No time - there is never enough time!

[surfindogg]

That's because there isn't any!!!!!!!!

[thing]

I must read this one. To challenge Dave's point that he he doesn't belive in past or future but only in 'now' ... well doesn't 'now' need past and future to define it? What, in the absence of past and future, does 'now' mean?

However, no, I think a sound point remains. I might not want to call it 'now' but I suspect we are somehow embedded in something that just 'is.'

The philosophers I have read seem to feel that if you lose past, present and future, you lose free will. I don't know if I buy this. To stick with the language we know, maybe the future 'already knows' what we decided.

A clear sky and a cloudy mind. Ah well...

Olly.

Now is a poor word to describe now..... We construct past and future because our mind is in glorious 3D and it need points of reference, plus there are interesting philosophical points about the ego being involved in these constructs but we won't go there.....that's not to say that the dinosaurs didn't roam the Earth and the Sun isn't going to become a lovely planetary neb but my gut instinct is that all of these things are happening now. Hard to put into words really and I have no empirical evidence for this so I can't really add anything else!!

The best way I can try to describe it is imagine a book, all of the story is there, but you as the reader start the book at time 0 and finish it at time 1. But to the book there is no time, it's pages are already there, it's just our reading of them that gives us the illusion of the passage of time. All of the pages are there all of the time and at the same instant.

TBH that's a pretty poor analogy of what I'm trying to say but it's the closest I can get with my 3D mind...

[kniclander]

last night, in the pub, the landlord called "time gentlemen plaase". I explained to him that time did not exist but he insisted (quite forcefully I might add) that it did. Ouch.

[Bigwings]

My dog sits by its foodbowl every night at 6 pm without reference to a clock. If I dont feed it she barks. She has an inbuilt "Timepiece"??? Try telling her time is a psychological or social construct.

[thing]

My dog sits by its foodbowl every night at 6 pm without reference to a clock. If I dont feed it she barks. She has an inbuilt "Timepiece"??? Try telling her time is a psychological or social construct.

Dogs don't exist, you just imagine they do.........

[themos]

There is no dog?

[MartinB]

My dog sits by its foodbowl every night at 6 pm without reference to a clock. If I dont feed it she barks. She has an inbuilt "Timepiece"??? Try telling her time is a psychological or social construct.

Dogs don't exist, you just imagine they do.........

[GazOC]

There is no dog?

Its Schrodingers dog.