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Why does time require matter ?

by phinds
Tags: matter, require, time
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shifty88
#91
Jan27-12, 11:02 AM
P: 53
Take a look at this link. I found it quite helpfull. Allthough i don't know the authors credentials its seems like he knows what he is on about

http://www.timephysics.com/what-is-time.html
phinds
#92
Jan27-12, 11:41 AM
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Quote Quote by shifty88 View Post
Take a look at this link. I found it quite helpfull. Allthough i don't know the authors credentials its seems like he knows what he is on about

http://www.timephysics.com/what-is-time.html
Mildly interesting, but I find it somewhat silly to conclude that time is just a construct of the human mind. I think time exists whether we do or not, as Dave pointed out way back up somewhere in this thread.
phinds
#93
Jan27-12, 11:46 AM
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Quote Quote by budrap View Post
I am indeed saying that time does not exist independently of the physical processes with which we measure it, that time is a characteristic of physical processes. And I'm saying that not because I simply feel that way about it but for the straight forward scientific reason that I know of no empirical evidence supporting the view that time has an independent existence.

Elsewhere in this thread you ask for factual information rather than opinions so let me turn that request back on your original question. In it you assume that time exists independently now and ask only if it will exist in some hypothetical future in the absence of matter and energy. My question to you then is what factual information supports your assumption that independent time exists now?
I cannot argue with your statements. You may well have it right. That's all at the heart of my original question. I started out believing strongly that time exists independent from matter and motion, but I am now much less convinced of that. I remain firmly convinced that time exists independent of human observation and that to think otherwise is just silly, and it is this belief that lends (to me) some credence to my continuing, albeit less firm, belief, that time may exist independent of matter and motion.
Fuzzy Logic
#94
Jan27-12, 12:50 PM
P: 38
You can think of it how you want, independent or dependent. It's a matter of perspective only.

Just like numbers. Do numbers really exist or is math just a construct of the human mind? If you start counting from 1, was there a before 1?

The scientific argument would be, do you care what is before 1? Does it make any difference, if all we know is definable with positive numbers?

Personally I would say it does make a huge difference (to know if time is finite or not), but there is no practical application for knowing.
juanrga
#95
Jan27-12, 02:00 PM
P: 476
Quote Quote by phinds View Post
I have read in serveral posts here that the concept of time in a total void is meaningless. That is, many scadzillions of years from now, assuming the expansion continues and black holes evaporate, and all goes REALLY dark (yes, I'm talking about a LONG time), the concept is that time loses its meaning because there's no way to measure it.

This really is perhaps one of those silly semantic arguments that I usually do not care for but this one is bugging me for some reason.

I GET completely the fact that you can't MEASURE time without matter but the concept that time just stops passing doesn't make sense to me. It is a somewhat pointless distinction, since even if time goes on, nothing HAPPENS. It's just the concept that "time stops" that bothers me and that SEEMS to be what I'm hearing from some of the threads here.

I'd appreciate any comments anyone has on this? Do you think time doesn't exist if you can't measure it because there's nothing to make clocks out of (and even no subatomic interactions to measure your ticks by) ?

Thanks,

Paul

By the way, I put this in cosmology since I can't think where ELSE to put it ... if a mod wants to move it, fine by me.
As the Nobel laureate said once:

Quote Quote by Ilya Prigogine
Time is previous to existence
salvestrom
#96
Jan27-12, 02:40 PM
P: 226
I find myself considering two view points.

1) Time is a consequence of the universe, a property of space under compression. Not even that, merely a construct for measuring something we can't define in the absence of the construction.

2) Time is the absolute driving force of our universe, without which there would be no beginning, no expansion, no movement or anything else. More precisely, movement through the dimension of time started expansion, causing the beginning. Sort as if time were an explosion, upon whose leading shockwave space now expands.
DaveC426913
#97
Jan27-12, 02:51 PM
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3) Time is simply a dimension, much like the other 3 spatial dimensions. No point in the universe can be uniquely defined without specifying four coordinates. The major difference between the time-like dimension and the space-like dimensions is that have no control over our speed or direction through the former.
salvestrom
#98
Jan27-12, 03:21 PM
P: 226
Quote Quote by DaveC426913 View Post
3) Time is simply a dimension, much like the other 3 spatial dimensions. No point in the universe can be uniquely defined without specifying four coordinates. The major difference between the time-like dimension and the space-like dimensions is that have no control over our speed or direction through the former.
This description can be used for either 1 or 2. In particularly it corresponds most directly to 1.
Fuzzy Logic
#99
Jan27-12, 05:40 PM
P: 38
Quote Quote by salvestrom View Post
This description can be used for either 1 or 2. In particularly it corresponds most directly to 1.
Time is neither a consequence or a force. Only a unit of measure.
Energy is the cause for change, not time. Time is how we quantify change.
salvestrom
#100
Jan27-12, 06:10 PM
P: 226
Quote Quote by Fuzzy Logic View Post
Time is neither a consequence or a force. Only a unit of measure.
Energy is the cause for change, not time. Time is how we quantify change.
Energy does nothing without time. The quantifying of the interval of two changes is a human construct using arbitrary units. The interval as a reality is something different. It is unhelpfully also named time.

The interval could easily be seen as a force or a consequence. It is intimately linked with space. Under compression it passes slower. In expansion it may pass faster, depending on how one defines the expansion. A ballon's expansion is stretching of the material. The expansion of a territory is a growth in the amount of land it encompasses. The former necessarily includes an increase in the passing of time. The latter does not.

Space and time, linked, means that passing time - an increase in the dimension of time - expands space - an increase in the dimension of space (this would seem to support the idea of the growth of space). With nothing to oppose this, space will expanded indefinitely.

Taking the ballon analogy, the center is the beginning of time, the interior the past, the surface the present, the outside the as yet unreached future.

I propose this as a logical extension of the concept of spacetime. In this it might be seen that spacetime is presented as a driving force for the development of the universe purely by its very nature.

This is only one point of view on the nature of time, as reflected in a prior post of mine where I put forward two different concepts of time which give different answers to the OP's original question.
budrap
#101
Jan28-12, 02:42 PM
P: 40
Quote Quote by DaveC426913 View Post
3) Time is simply a dimension, much like the other 3 spatial dimensions. No point in the universe can be uniquely defined without specifying four coordinates. The major difference between the time-like dimension and the space-like dimensions is that have no control over our speed or direction through the former.
That doesn't address the question though, which would be in this context: Are the time or spacetime dimensions independent of matter-energy or simply manifestations of their interactions?
budrap
#102
Jan28-12, 03:35 PM
P: 40
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Quote Quote by phinds View Post
I cannot argue with your statements. You may well have it right. That's all at the heart of my original question. I started out believing strongly that time exists independent from matter and motion, but I am now much less convinced of that. I remain firmly convinced that time exists independent of human observation and that to think otherwise is just silly, and it is this belief that lends (to me) some credence to my continuing, albeit less firm, belief, that time may exist independent of matter and motion.
I think that your difficulties in this area are largely related to an uncertainty regarding the border between philosophy and science. Philosophy is much more accommodating of beliefs than is science. Beliefs in science are only admissible as hunches or hypotheses to be tested against the empirical baseline that is the sine qua non of all science.

So it's good that you are less certain of the scientific validity of your belief in the independent existence of time; it speaks of an open mind amenable to scientific discourse. A useful approach toward resolving your current apparent uncertainties would be to get your philosophical side to propose an observation or experiment that might conclusively prove or disprove the independent existence of time to the satisfaction of your scientific side.
salvestrom
#103
Jan28-12, 03:46 PM
P: 226
Quote Quote by budrap View Post
A useful approach toward resolving your current apparent uncertainties would be to get your philosophical side to propose an observation or experiment that might conclusively prove or disprove the independent existence of time to the satisfaction of your scientific side.
Awesome suggestion. Unfortunately, I have no idea how to measure the passing of time between galactic filaments...

Anyone know how to calculate the circumference of a circle where the radius is a unit of time and the arc is a unit of distance...? Don't answer that...
Chronos
#104
Jan28-12, 04:29 PM
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Time and space are thought to be a consequence of gravity. Theoretically, without gravity, there would be no time or space -
re: http://www.astronomycafe.net/gravity/gravity.html

"Perhaps the most unusual thing about gravity we know about is that, unlike the other forces of nature, gravity is intimately related to space and time. In fact, space and time are viewed by physicists, and the mathematics of relativity theory, as qualities of the gravitational field of the cosmos that have no independent existence. Gravity does not exist like the frosting on a cake, embedded in some larger arena of space and time. Instead, the 'frosting' is everything, and matter is embedded and intimately and indivisibly connected to it. If you could turn off gravity, it is mathematically predicted that space and time would also vanish!"
budrap
#105
Jan28-12, 05:22 PM
P: 40
Quote Quote by Chronos View Post
" In fact, space and time are viewed by physicists, and the mathematics of relativity theory, as qualities of the gravitational field of the cosmos that have no independent existence.
But on the cosmological scale spacetime appears to be flat which can only mean that there is no cosmological gravitational field, no?
salvestrom
#106
Jan28-12, 07:08 PM
P: 226
Quote Quote by Chronos View Post
... In fact, space and time are viewed by physicists, and the mathematics of relativity theory, as qualities of the gravitational field of the cosmos that have no independent existence...
This is a mainstream view?
Chalnoth
#107
Jan28-12, 07:17 PM
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Quote Quote by salvestrom View Post
This is a mainstream view?
Yes. Space-time is curved, and gravity describes that curvature and how it is related to matter.
salvestrom
#108
Jan28-12, 08:59 PM
P: 226
Quote Quote by Chalnoth View Post
Yes. Space-time is curved, and gravity describes that curvature and how it is related to matter.
That isn't the portion I was seeking clarification on. I was inquiring about the statement that neither have an independent existance. The link he is quoting from goes as far as to state without gravity both vanish.


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