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Author Topic: What is Time? If there was no light would Time cease to be?  (Read 61152 times)

Offline king5118

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What is Time? If there was no light would Time cease to be?
« Reply #25 on: 27/10/2010 10:00:15 »
Light is a human invention and is linked to the past and future, but you are quite right in saying that it is also linked to light. If we hadn't invented time we would still rely on the sun and moon to measure our activities throughout the day and night. People get so wrapped up with time and forget that as an invention by us it can be abused and used to explain so many things. I would say that the main focus of our attention should be distance and not time. It is theoretically possible to travel faster than light and just takes someone to come up with the idea.
 

Offline king5118

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What is Time? If there was no light would Time cease to be?
« Reply #26 on: 27/10/2010 10:16:32 »
If our sun didn't exist and the stars that we can see were using the light of their own galaxies then could we still say that they were in the past? Or is it relative to where we are in conjunction with them.
 

Offline Bill S

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What is Time? If there was no light would Time cease to be?
« Reply #27 on: 27/10/2010 16:07:56 »
Quote from: imatfaal
no it would be really boring!

Of course it would be boring if a language in which each word had only one meaning were the only language we had, but there could be advantages to having a sort of techno-speak in which everyone could agree on definitions.   
 

Offline Bill S

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What is Time? If there was no light would Time cease to be?
« Reply #28 on: 27/10/2010 16:13:40 »
Quote from: King5118
It is theoretically possible to travel faster than light and just takes someone to come up with the idea.

Relativity does not preclude travelling at superluminal speed.  My understanding is that serious problems arise if you try to accelerate from sub- to super-luminal speed.  are you saying that that is theoretically possible?
 

Offline Bill S

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What is Time? If there was no light would Time cease to be?
« Reply #29 on: 27/10/2010 16:26:38 »
Quote from: King5118
If our sun didn't exist and the stars that we can see were using the light of their own galaxies then could we still say that they were in the past? Or is it relative to where we are in conjunction with them.

I'm not sure that I follow this.  What difference would the absence of our sun make to the scenario?
The fact that we see distant stars, galaxies etc. as they were in the past is due to the length of time their light takes to reach us.  This even applies to our sun; we see it as it was about 8 mins ago.
Could it be that we create some of our own problems by thinking of time as "flowing"?  It might be simpler (some hopes  ;D)to think of time as static, and ourselves as travelling through it.
 

Offline simplified

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What is Time? If there was no light would Time cease to be?
« Reply #30 on: 28/10/2010 14:42:32 »
Moving cannot be without time.
 

Offline Ron Hughes

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What is Time? If there was no light would Time cease to be?
« Reply #31 on: 28/10/2010 15:25:36 »
Suppose that the Universe consisted of only a single electron, would time exist? The quick answer would be no because nothing is moving with respect to anything else.That is not entirely true and I will explain if anyone asks. Now suppose we insert another electron, that is in motion WRT the other electron, into the Universe. Now there are two electric fields in our hypothetical Universe and they are changing with WRT each other. Time is any change WRT something else.
 

Offline Bill S

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What is Time? If there was no light would Time cease to be?
« Reply #32 on: 28/10/2010 23:23:00 »
Quote from: Ron Hughes
Suppose that the Universe consisted of only a single electron, would time exist? The quick answer would be no because nothing is moving with respect to anything else.That is not entirely true and I will explain if anyone asks.

Explanation, please.
 

Offline CPT ArkAngel

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What is Time? If there was no light would Time cease to be?
« Reply #33 on: 29/10/2010 03:00:14 »
The event horizon of a particle or a black hole is defining the 0 timerate of it. Gravity around it defines the local timerate. According to photon Theory, there is a point in the middle (not really a singularity but due to symmetry of the gravitational field) where the timerate is 0. This point will move according to interference with the event horizon from outside fields.
 

Offline Ron Hughes

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What is Time? If there was no light would Time cease to be?
« Reply #34 on: 29/10/2010 03:13:29 »
(Play like) you were an entity capable of creating space/time and the matter that makes our Universe. Instead you create only a single electron which would include it's electric field. At the instant you create it that electric field would start expanding at C, This expanding field would obey the inverse square law which would mean that time and space started at the instant the electron was created.
« Last Edit: 29/10/2010 15:44:51 by Ron Hughes »
 

Offline Bill S

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What is Time? If there was no light would Time cease to be?
« Reply #35 on: 29/10/2010 22:10:28 »
Thanks R H.  Just to make sure we are not running into Mark McCutcheon's expanding electrons [:o)], it is only the electric field that expands?
 

Offline Ron Hughes

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What is Time? If there was no light would Time cease to be?
« Reply #36 on: 29/10/2010 23:25:04 »
Yes the field is what expands. If you somehow move the electron that will create a photon. You could ask, move it with respect to what? The answer is move it with respect to the expanding field that started from it's original position.
« Last Edit: 29/10/2010 23:28:41 by Ron Hughes »
 

Offline Bill S

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What is Time? If there was no light would Time cease to be?
« Reply #37 on: 30/10/2010 17:02:01 »
Quote from: R H
If you somehow move the electron that will create a photon.

Is that because you would have to hit the electron with something to move it, and the collision would "create a photon"? 
Would it matter what you used to hit the electron?
 

Offline Ron Hughes

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« Last Edit: 30/10/2010 17:30:56 by Ron Hughes »
 

Offline simplified

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What is Time? If there was no light would Time cease to be?
« Reply #39 on: 18/01/2011 16:19:14 »
Propagation of my time definition:
   "Time is quantity of motion"  ;)
 

Offline QuantumClue

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What is Time? If there was no light would Time cease to be?
« Reply #40 on: 18/01/2011 21:28:15 »
Time is in three parts:  Future-which never arrives and exists only in ones' imagination.  Present-which exists only for an infinitesimal split second and Past which goes on forever in ones' memory but never returns except as mistakes which we make and are inclined to repeat.  Thanks for comments.  Joe L. Ogan

This is wrong. Time does not have a description of past, present and future. These objects do not exist within relativity and quantum theory.
 

Offline QuantumClue

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What is Time? If there was no light would Time cease to be?
« Reply #41 on: 18/01/2011 21:31:54 »
Propagation of my time definition:
   "Time is quantity of motion"  ;)

This is also wrong. This is a Newtonian definition of time. Time does not equal motion.
 

Offline QuantumClue

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What is Time? If there was no light would Time cease to be?
« Reply #42 on: 18/01/2011 21:33:05 »
Moving cannot be without time.

Since time is quantized in quantum mechanics, and since time has no flow in relativity, this is not true.
 

Offline Geezer

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What is Time? If there was no light would Time cease to be?
« Reply #43 on: 18/01/2011 21:46:58 »
Propagation of my time definition:
   "Time is quantity of motion"  ;)

This is also wrong. This is a Newtonian definition of time. Time does not equal motion.

Time is measured in terms of motion. Just because it's Newtonian, it does not mean it's "wrong".

Also, unless you are only trying to start an argument, if you believe something is wrong, it would be nice if you provided an explanation for why you think it's wrong.

Can you explain how you are able to measure time without motion?
 

Offline QuantumClue

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What is Time? If there was no light would Time cease to be?
« Reply #44 on: 18/01/2011 21:50:58 »
Suppose that the Universe consisted of only a single electron, would time exist? The quick answer would be no because nothing is moving with respect to anything else.That is not entirely true and I will explain if anyone asks. Now suppose we insert another electron, that is in motion WRT the other electron, into the Universe. Now there are two electric fields in our hypothetical Universe and they are changing with WRT each other. Time is any change WRT something else.

This is probably the best explanation I've heard so far. However, just because we have more than one moving object in our universe does not mean that clocks necesserily tick.

Explaining why is a little harder to explain. Time evolution, like you would find in the Schrodinger equation (you could even look at the writeup recently which has a small part on the evolution equation) is a type of diffeomorphism. Time constraints in a classical Hamiltonian will eventually find the Schrodinger Equation effectively having no time description.

This is called the Wheeler de Witt equation, and its at the heart of quantum theory and General Relativity.
« Last Edit: 18/01/2011 21:52:29 by QuantumClue »
 

Offline QuantumClue

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What is Time? If there was no light would Time cease to be?
« Reply #45 on: 18/01/2011 21:52:09 »
Propagation of my time definition:
   "Time is quantity of motion"  ;)

This is also wrong. This is a Newtonian definition of time. Time does not equal motion.

Time is measured in terms of motion. Just because it's Newtonian, it does not mean it's "wrong".

Also, unless you are only trying to start an argument, if you believe something is wrong, it would be nice if you provided an explanation for why you think it's wrong.

Can you explain how you are able to measure time without motion?

Oh it is wrong. Motion does not equate to time. In general relativity motion ceases to exist, we have what are called pure gravity models. If the universe was an object, internal energies ceases to move due to the Wheeler de Witt equation.
 

Offline Geezer

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What is Time? If there was no light would Time cease to be?
« Reply #46 on: 18/01/2011 22:17:35 »
Propagation of my time definition:
   "Time is quantity of motion"  ;)

This is also wrong. This is a Newtonian definition of time. Time does not equal motion.

Time is measured in terms of motion. Just because it's Newtonian, it does not mean it's "wrong".

Also, unless you are only trying to start an argument, if you believe something is wrong, it would be nice if you provided an explanation for why you think it's wrong.

Can you explain how you are able to measure time without motion?

Oh it is wrong. Motion does not equate to time. In general relativity motion ceases to exist, we have what are called pure gravity models. If the universe was an object, internal energies ceases to move due to the Wheeler de Witt equation.

That does not answer my question. How do you measure time?
 

Offline QuantumClue

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What is Time? If there was no light would Time cease to be?
« Reply #47 on: 18/01/2011 22:30:23 »
Propagation of my time definition:
   "Time is quantity of motion"  ;)

This is also wrong. This is a Newtonian definition of time. Time does not equal motion.

Time is measured in terms of motion. Just because it's Newtonian, it does not mean it's "wrong".

Also, unless you are only trying to start an argument, if you believe something is wrong, it would be nice if you provided an explanation for why you think it's wrong.

Can you explain how you are able to measure time without motion?

Oh it is wrong. Motion does not equate to time. In general relativity motion ceases to exist, we have what are called pure gravity models. If the universe was an object, internal energies ceases to move due to the Wheeler de Witt equation.

That does not answer my question. How do you measure time?

We are not sure you can in General Relativity. Matter fields vanish, and what is left is an energy field which does not change at all.

In quantum theory, it looks like an approach to this is to measure motion as static frames of tiny little moments called the Planck Time. In theory, time does not have flow, but is a succession of tiny beginnings and ends, each existing for the smallest frame of time possible, and so does not contain a motion as such, not a continuous one any way.
 

Offline Geezer

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What is Time? If there was no light would Time cease to be?
« Reply #48 on: 18/01/2011 22:32:29 »
Propagation of my time definition:
   "Time is quantity of motion"  ;)

This is also wrong. This is a Newtonian definition of time. Time does not equal motion.

Time is measured in terms of motion. Just because it's Newtonian, it does not mean it's "wrong".

Also, unless you are only trying to start an argument, if you believe something is wrong, it would be nice if you provided an explanation for why you think it's wrong.

Can you explain how you are able to measure time without motion?

Oh it is wrong. Motion does not equate to time. In general relativity motion ceases to exist, we have what are called pure gravity models. If the universe was an object, internal energies ceases to move due to the Wheeler de Witt equation.

That does not answer my question. How do you measure time?

We are not sure you can in General Relativity. Matter fields vanish, and what is left is an energy field which does not change at all.

In quantum theory, it looks like an approach to this is to measure motion as static frames of tiny little moments called the Planck Time. In theory, time does not have flow, but is a succession of tiny beginnings and ends, each existing for the smallest frame of time possible, and so does not contain a motion as such, not a continuous one any way.

Yes, but how do you measure time without motion?
 

Offline QuantumClue

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What is Time? If there was no light would Time cease to be?
« Reply #49 on: 18/01/2011 22:36:46 »
That's the stubborn illusion of reality Einstein often talked about. Past and future seem to be stubbornly persistent illusions - motion is measured with our equations, but the truth and crux of the matter is that a unified approach will not use the classical postulations of equations of motion. They will adhere to support the framework of relativity.
 

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What is Time? If there was no light would Time cease to be?
« Reply #49 on: 18/01/2011 22:36:46 »

 

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