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View Full Version : What exactly is 'time' ? please define.



eliquant
20th March 2009, 22:48
I started thinking about "time" as an 'element', as a 'force', as a concept .... what the hell is it exactly !!?!? and where does it come from !!!!?

Cliphead
20th March 2009, 23:27
Time is nature's way of stopping everything happening at once.

Attributed to John Archibald Wheeler

moorfield
20th March 2009, 23:29
Time is Money, plus 15% VAT, it comes from unwitting ClientCos.

BolshieBastard
20th March 2009, 23:49
I started thinking about "time" as an 'element', as a 'force', as a concept .... what the hell is it exactly !!?!? and where does it come from !!!!?

Give us a minute to explain.............

gingerjedi
21st March 2009, 08:54
A clock representing man's impending doom is as nourishing to the mind as a photograph of oxygen to a drowning man. -Jon Osterman

scooterscot
21st March 2009, 09:31
Time is nature's way of stopping everything happening at once.

Attributed to John Archibald Wheeler

I've been saying this for years!

pmeswani
21st March 2009, 09:43
I've been saying this for years!

Well I guess it's time to make a stand then.

HairyArsedBloke
21st March 2009, 09:51
Time is an illusion. Lunchtime doubly so.

EternalOptimist
21st March 2009, 10:09
I started thinking about "time" as an 'element', as a 'force', as a concept .... what the hell is it exactly !!?!? and where does it come from !!!!?

Time can be looked at in two ways, the first is as a subject of philosophical exploration, the second way is by using intuition.

The first way of looking at time has a whole load of problems, it's only humans who do this so it's subjective, the language gets in the way, the way the human brain works gets in the way. If science tells us something that is fundamentally opposed to what we observe, which do we believe ?

The second way of looking at time is by using intuition. We just 'know' what it is. The dinosaurs understood time, they couldnt get by without knowing. Humans evolved with the same understanding of time, if it was good enough to get us evolved to this point, maybe thats all we need to know.

We just 'know' that there is a past, a present and a future. We just 'know' that the food we ate last week is not going to be there next week, it's in the past. We just 'know' that if we fire an arrow it will get to its target in a certain amount of time. It's not going to stop, its not going to go backwards.

Science, on the other hand, tells us that time is a variable, it can speed up and slow down. At least it goes in the same direction as intuitive time though, which is a bonus. Philosophers will say that this might be an illusion, time can go in the other direction, like un-drinking a pint of lager back into the glass, then getting younger till we get unconceived.

what exactly is it?

It has a lot of the properties of a law. If you make a fixed length pendulum, it will swing in a frequency that is a constant multiple of the half life of uranium. Its not possible to take a law and look at it in a test tube.


where does it come from ?

Science tells us that it was not created, it has always existed. The big bang is a result of cause and effect, a cause and its effect are seperated by time, therefore time must have preceded the big bang and could not have been created by it.

intuition tells us that it doesnt actually exist as a thing. It simply a way of describing that one event occurs after another, always has done and always will.




:rolleyes:

DaveB
21st March 2009, 10:14
Time is nature's way of stopping everything happening at once.

Attributed to John Archibald Wheeler

Space is natures way of stopping it all happening to you.

TimberWolf
21st March 2009, 10:47
I started thinking about "time" as an 'element', as a 'force', as a concept .... what the hell is it exactly !!?!? and where does it come from !!!!?

Newton assumed time was absolute (a big clock that ticks at the same rate for the whole universe), but Einstein tells us that time is relative (your wristwatch won't tick at the same rate or tell the same time for all observers). As a consequence of the postulate that the speed of light being constant for all observers, time and space were connected (into space-time) and in this space events can be agreed by all observers.

I quite like the speculation that time is a statistical process, based on a lot of juju happening outside our familiar dimensions. Anyway, without it we would be in deep tulip, as in not even existing.

OwlHoot
21st March 2009, 10:49
Time is a dynamical parameter which allows a Lagrangian to be integrable (http://arxiv.org/abs/hep-th/0208189), which is the case if it admits a foliation (http://en.wikipedia.org/wiki/Foliation).

HTH :glasses

VectraMan
21st March 2009, 10:52
Time is 10:51, no wait... 10.52.

scooterscot
21st March 2009, 11:02
Time is change - think about it.... if movement is not allowed to occur on smallest scale how can time exist?

EO makes a good point about the human perception. Did you know that here in the UK we think of time as in front of us and the past behind us, however in Italy they believe the future is above and the past is below them - don't think about it.

Ivor Bigun
21st March 2009, 11:14
Time is 10:51, no wait... 10.52.

Our perception of time, is what time is.
What we see is not real, it is a reflected 2D image.
Our sensation of touch does not make something "real"

We think something is "real" because we see it and touch it at the same time) We, as humans only know "reality" by the instant. Time is the gap between these "realities" and as such is less important.
We stretch and slow down our perception of time constantly yet we are not normally aware of it.

Consider yourself, waiting for the phone to be answered, the phone is ringing "Durr Durr" etc
Take the phone away from your ear for a short while, then put it back to your ear. On a few occasions, you will be suprised how long the silence is - It will appear longer until you hear it eventually ring.
After you've heard it, the silence gaps appear to be normal.

What is happening?
When you hear something rythmic, part of your "flight or fight" brain shuts off.
The brain "knows" that there will be a ring so it goes into your normal "concious" thinking which is quite deliberate (multitasking if you like) - rather like holding an image in your head as opposed to being "blank" .

When you take your ear away from the telephone and put it back, that part of the concious brain is "reset to blank" and the instant you put the telephone to your ear, you start hearing the rings with the raw "fight or flight" part of your brain (your subconcious/instinct) This is faster i.e. time appears slower. That is why it appears that the silence gap is longer. You may even feel a slight "fear" before you hear the eventual ring. When your brain has established the pattern, you no longer feel that fear.

AlfredJPruffock
21st March 2009, 11:17
Time is - not what you think it is.

Ivor Bigun
21st March 2009, 11:28
Our perception of time, is what time is.
When you hear something rythmic, part of your "flight or fight" brain shuts off.
The brain "knows" that there will be a ring so it goes into your normal "concious" thinking which is quite deliberate (multitasking if you like) - rather like holding an image in your head as opposed to being "blank" .


What I should have added - is that when you are "enjoying" yourself, time passes quickly. Why? because whatever you are enjoying is tripping your brain into a concious "steady state" - similar to being asleep.
The most powerful "time slip" device your brain has, is of course when you are asleep.

When you are bored, you are thinking more with your "flight or fight" part of your brain - almost constantly - this is very expensive in terms of "alertness" and can give rise to feeling blue as sugars drop. Its Nature's way of slowing you down to give your body a rest.

EternalOptimist
21st March 2009, 11:38
Ivor

you are concentrating on the human psychological awareness of time. If you think about time, it passes slowly. A watched pot never boils.

Have you ever gotten into your car for a long journey, then stepped out and thought, 'that went fast'. Other times it can seem like an eternity.

but time passes for cats and dogs. and daffodils.



:rolleyes:

Liability
21st March 2009, 11:48
time is simply a timer as to how long you have left to die.

NotAllThere
21st March 2009, 12:18
It is incorrect to say that there was time before the big bang, because it didn't have a cause. Time came into existence at the time of the big bang. That was settled by Augustine.

Time is merely distance travelled in at right angles to the three dimensional space we think we live in. One second is 186 million metres.

Ivor Bigun
21st March 2009, 14:48
Ivor

you are concentrating on the human psychological awareness of time. If you think about time, it passes slowly. A watched pot never boils.

Have you ever gotten into your car for a long journey, then stepped out and thought, 'that went fast'. Other times it can seem like an eternity.

but time passes for cats and dogs. and daffodils.

:rolleyes:

Indeed EO. However, I would like to postulate that there is no other way of "experiencing" time.

Sure, we can translate what we experience into the absolute world of math, but to prove the math works, we need to observe the outcome.
e.g. time slows down on satelites.

Going off on a tangent for a moment, we also have to accept the premise (law) that "1 + 1 = 2". i.e. we mustn't lose sight (!) that this law is itself based on observations using the senses in a 3d world.
Just because the majority of people here believe in the church of "1+1=2", it doesn't mean it is an absolute truth. I'm sure the dogs and daffodils would agree here - they nothing of this secret abstract world. Why should they? they don't need it.

Also, Time is not constant across the universe - It is progressing differently in different areas of the galaxy right now (fact).

Math also allows for the possibility that time is really going backwards but we perceive it as going forwards.
- Especially on a Monday morning.......:wink

So what exactly is time?
I'm just saying its something that we experience and are able to abstract into the form of math.

IMO, the fact that we observe it, it exists.

threaded
21st March 2009, 21:46
Tempora mutantur, nos et mutamur in illis; Quo modo? fit semper tempore pejor homo.

OwlHoot
21st March 2009, 22:05
"Tempus item per se non est, sed rebus ab ipsis
consequitur sensus, transactum quid sit in aevo,
tum quae res instet, quid porro deinde sequatur;
nec per se quemquam tempus sentire fatendumst
semotum ab rerum motu placidaque quiete."

Lucretius, De rerum natura (http://en.wikipedia.org/wiki/On_the_Nature_of_Things)

(full text here) (http://www.thelatinlibrary.com/lucretius/lucretius1.shtml)

"Similarly, time by itself does not exist; but from things themselves there results a sense of what has already occurred, what is now going on, and what is to ensue. It must not be claimed that anyone can sense time itself apart from the movement of things or their restful immobility"

Doggy Styles
22nd March 2009, 10:44
Time must have always existed, otherwise there would have been nothing for the big bang to start in.

threaded
22nd March 2009, 12:01
Time must have always existed, otherwise there would have been nothing for the big bang to start in.

:rollin:

NotAllThere
22nd March 2009, 19:36
Time must have always existed, otherwise there would have been nothing for the big bang to start in.

:suicide:

Fruit flies. Time walks.

Doggy Styles
22nd March 2009, 22:32
Steady on! :laugh

All you guys think you know various answers, but nobody has ever proved what time is.

It's just comparing the longevity between events with longevity between some more events. The rest is just made-up b*ll*cks. Einstein would agree with me.

Board Game Geek
23rd March 2009, 00:19
I would say that Time is :

The transitive state of any atom in the known universe.

Whilst the imagined concept of time on an individual biological level varies between organisms, at the top level it is the same for all us.

Imagine a man, puppy, a mayfly and an elephant.

Time on the individual biological level affects each of these organisms at different rates.

Now imagine all of these creatures are passengers in the Great Universal Bus.

They, and everything else in the universe, are inside the bus, encapuslated by it, if you like.

Time, at the top level, is the bus, and the motion it makes as it expands through space.

There is nothing "beyond" the bus. The bus is the final arbiter of time.

Therefore, I'd argue that time is the transtive motion of the Universe. Possibly even the existence and being of the Universe, regardless of motion.

NotAllThere
23rd March 2009, 06:28
The speed of time is well established. 1 second per second.

Gonzo
23rd March 2009, 07:21
I agree this has become an increasingly complex issue over the past few years.

In the olden days, time was called at 11:00pm sharp (or 10:30pm on a Sunday). It was the same everywhere, and everyone knew where they were.

With the lifting of the restrictions on opening hours you can never be sure exactly when particular licensed premises are going to close so if you're out on a pub-crawl it is a bit of a nightmare towards the end.

I blame the Government. :rolleyes:

EternalOptimist
23rd March 2009, 07:59
I would say that Time is :

The transitive state of any atom in the known universe.

Whilst the imagined concept of time on an individual biological level varies between organisms, at the top level it is the same for all us.



Well now you have an interesting problem. Imagine a vacuum, there are no atoms in the vacuum, therefore no time.
take it further.
Imagine a valve radio, with a clock on the front. Time exists for most of the radio, because it has atoms, but the bit that makes the radio work, the inside of the vacuum tubes, has no time.

this does not chime with what we intuitively 'know' - that time exists for the whole radio.




:rolleyes:

NotAllThere
23rd March 2009, 08:15
There are no perfect vacuums. ( And Dyson doesn't count ). But even if there were, you'd still have protons, neutrons and other particals popping in and out of existence, in accordance with the Heisenberg Uncertainty Principle.

That this actually does happen is demonstrated by the Casimir effect.

And it's not the vacuum inside a vacuum tube that makes the radio work. It's the absence of anything to absorb the electron stream. A subtle, but important distinction. Rather like it isn't the air that allows you to pee into a toilet, it's the fact that the lid is up that's importnant.

EternalOptimist
23rd March 2009, 08:23
This has got absolutely nothing to do with heisenbergs uncertainty principle. It is about the intuitive view of time. In that view, there are vacuums, and therefore tying time to atoms and transistion does not hold water.




:rolleyes:

NotAllThere
23rd March 2009, 08:24
But intuitive views of anything involving quantum mechanics, atoms or transistions is 100% wrong. QM is counter-intuitive.

EternalOptimist
23rd March 2009, 08:28
But intuitive views of anything involving quantum mechanics, atoms or transistions is 100% wrong. QM is counter-intuitive.

exactly. and if you read my earlier post you will see that.
Now this leaves YOU with a problem. The intuitive view of time helped the dinosaurs and humans evolve, so how wrong can it be ?


:rolleyes:

NotAllThere
23rd March 2009, 08:31
Completely. Dinosaur bones were laid down by the planetary engineers who constructed our planet to give us a sense of history. ( And the complete fossilised remains of a T-Rex with a ban-the-bomb placard was put down just to confuse the paleontologists. Which is why it's suppressed by the men in black. )

expat
23rd March 2009, 08:53
There are no perfect vacuums. ( And Dyson doesn't count ). But even if there were, you'd still have protons, neutrons and other particals popping in and out of existence, in accordance with the Heisenberg Uncertainty Principle.

That this actually does happen is demonstrated by the Casimir effect.

And it's not the vacuum inside a vacuum tube that makes the radio work. It's the absence of anything to absorb the electron stream. A subtle, but important distinction. Rather like it isn't the air that allows you to pee into a toilet, it's the fact that the lid is up that's importnant.Way WAY too good for this board!

AlfredJPruffock
23rd March 2009, 09:00
Completely. Dinosaur bones were laid down by the planetary engineers who constructed our planet to give us a sense of history. ( And the complete fossilised remains of a T-Rex with a ban-the-bomb placard was put down just to confuse the paleontologists. Which is why it's suppressed by the men in black. )

No they were not ! Laughed the Children of Gong


Time - in Vodka and Red Wine
Demanding Billy Shears
And other Friends of Mine ....

Take your Time

Time - is not what you think it is.

NotAllThere
23rd March 2009, 09:11
Ticking away the moments that make up a dull day
You fritter and waste the hours in an off hand way
Kicking around on a piece of ground in your home town
Waiting for someone or something to show you the way

Tired of lying in the sunshine staying home to watch the rain
You are young and life is long and there is time to kill today
And then one day you find ten years have got behind you
No one told you when to run, you missed the starting gun

And you run and you run to catch up with the sun, but its sinking
And racing around to come up behind you again
The sun is the same in the relative way, but youre older
Shorter of breath and one day closer to death

Every year is getting shorter, never seem to find the time
Plans that either come to naught or half a page of scribbled lines
Hanging on in quiet desperation is the english way
The time is gone, the song is over, thought Id something more to say

Home, home again
I like to be here when I can
And when I come home cold and tired
Its good to warm my bones beside the fire
Far away across the field
The tolling of the iron bell
Calls the faithful to their knees
To hear the softly spoken magic spells.

That's Time, that is.

AlfredJPruffock
23rd March 2009, 10:04
[

That's Time, that is.

Oh No - it's not ! Cried the Children Of Gong

shaunbhoy
23rd March 2009, 10:12
"Time" is what the barman shouts when he decides that he is fed up serving alcoholic refreshments and wishes everyone to leave.

HTH