Go back
What really is time?

What really is time?

Posers and Puzzles

AThousandYoung
Chato de Shamrock

tinyurl.com/2s4b6bmx

Joined
23 Aug 04
Moves
26926
Clock
04 Jan 10
5 edits
Vote Up
Vote Down

Originally posted by Palynka
If time is just a measure of entropy, then entropy would exist without time? Mmm... Something doesn't add up. I've heard that entropy implies a direction of time, but time cannot simply be a measure.
I don't understand your post.

Entropy could exist without time, but a change in entropy could not.

A clock or watch is a device that creates entropy by turning chemical, mechanical or electrical potential energy into heat by doing work on the display, moving the hands or changing what pattern of light is displayed. As it creates entropy in a more or less unchanging pattern, the hands move at a specific, measurable rate, allowing us to measure the local change in entropy which acts as an estimate of the universal change in entropy.

P
Upward Spiral

Halfway

Joined
02 Aug 04
Moves
8702
Clock
04 Jan 10
Vote Up
Vote Down

Originally posted by AThousandYoung
I don't understand your post.

Entropy could exist without time, but a change in entropy could not.

A clock or watch is a device that creates entropy by turning chemical, mechanical or electrical potential energy into heat by doing work on the display, moving the hands or changing what pattern of light is displayed. As it creates entropy in a mo ...[text shortened]... asure the local change in entropy which acts as an estimate of the universal change in entropy.
I think I see what you mean.

But isn't time dilation a real phenomenon? How is that compatible with time being a measure of the entropy of the whole universe?

h

Joined
25 Apr 06
Moves
5939
Clock
04 Jan 10
1 edit
Vote Up
Vote Down

Originally posted by EmLasker
What really is time?
It's what you're wasting right now

u
The So Fist

Voice of Reason

Joined
28 Mar 06
Moves
9908
Clock
04 Jan 10
Vote Up
Vote Down

Originally posted by Palynka
I think I see what you mean.

But isn't time dilation a real phenomenon? How is that compatible with time being a measure of the entropy of the whole universe?
I've spent too much time reading this thread. It just comes down to whether or not you believe in absolute time.

Look, you guys are are just arguing different sides of the question. On one side you have newton, on the other you have Einstein. Now if one of you woud just throw in Hawking we'd be set. (even if he just repackaged and added some philosophy to it)

If none of this makes any sense to you, read the following:

http://library.thinkquest.org/06aug/02088/whatistime.htm

P
Upward Spiral

Halfway

Joined
02 Aug 04
Moves
8702
Clock
04 Jan 10
Vote Up
Vote Down

Originally posted by uzless
I've spent too much time reading this thread. It just comes down to whether or not you believe in absolute time.

Look, you guys are are just arguing different sides of the question. On one side you have newton, on the other you have Einstein. Now if one of you woud just throw in Hawking we'd be set. (even if he just repackaged and added some philosophy ...[text shortened]... sense to you, read the following:

http://library.thinkquest.org/06aug/02088/whatistime.htm
FAIL

ATY already threw in Hawking.

diver

Joined
16 Feb 08
Moves
121320
Clock
04 Jan 10
Vote Up
Vote Down

Originally posted by AThousandYoung
How can something move in space without moving in time? Movement in space is defined as distance/time.
Isn't that speed = distance/time?

P
Upward Spiral

Halfway

Joined
02 Aug 04
Moves
8702
Clock
05 Jan 10
Vote Up
Vote Down

Originally posted by divegeester
Isn't that speed = distance/time?
Tangent: I think that disagreement between me and ATY is that I see things more mathematically and he sees it more as physics. Movement for me is changing coordinates along the basic 3 dimensions. If I think of time as simply another coordinate (4D or more), then if I keep that coordinate fixed and change one of the first three, I have "movement" with time fixed.

Of course, this may be an abuse of language from me being a layman in physics.

wolfgang59
Quiz Master

RHP Arms

Joined
09 Jun 07
Moves
48794
Clock
05 Jan 10
Vote Up
Vote Down

Originally posted by Palynka
Tangent: I think that disagreement between me and ATY is that I see things more mathematically and he sees it more as physics. Movement for me is changing coordinates along the basic 3 dimensions. If I think of time as simply another coordinate (4D or more), then if I keep that coordinate fixed and change one of the first three, I have "movement" with time fixed.

Of course, this may be an abuse of language from me being a layman in physics.
Consider a point 'moving' while keeping t as constant. That means that at a single moment in time it occupies a number of places.

Doesnt it simply become a line, or plane or hyper-plane or perhaps just a series of points? I don't think that this could be considered movement.

'Moving' while t is constant isnt really movement in any practical sense.

Movement must involve time (whatever that is!)

P
Upward Spiral

Halfway

Joined
02 Aug 04
Moves
8702
Clock
05 Jan 10
1 edit
Vote Up
Vote Down

Originally posted by wolfgang59
Consider a point 'moving' while keeping t as constant. That means that at a single moment in time it occupies a number of places.

Doesnt it simply become a line, or plane or hyper-plane or perhaps just a series of points? I don't think that this could be considered movement.

'Moving' while t is constant isnt really movement in any practical sense.

Movement must involve time (whatever that is!)
Indeed... Like I said it depends on how you define movement, and I was defining more as a mathematician than as a physicist, so I was probably imprecise with my terminology.

AThousandYoung
Chato de Shamrock

tinyurl.com/2s4b6bmx

Joined
23 Aug 04
Moves
26926
Clock
06 Jan 10
Vote Up
Vote Down

Originally posted by wolfgang59
Consider a point 'moving' while keeping t as constant. That means that at a single moment in time it occupies a number of places.

Doesnt it simply become a line, or plane or hyper-plane or perhaps just a series of points? I don't think that this could be considered movement.

'Moving' while t is constant isnt really movement in any practical sense.

Movement must involve time (whatever that is!)
Much better explanation than mine!

E

Joined
28 Mar 07
Moves
5104
Clock
06 Jan 10
Vote Up
Vote Down

in other words: tick tock tick tock...

D
incipit parodia

Joined
01 Aug 07
Moves
46580
Clock
06 Jan 10
1 edit
Vote Up
Vote Down

Of course, plenty of respected thinkers (in mathematics and physics, as well as philosophy) will tell you that time does not exist...

I first came accross the notion in the pop-science book What We Believe But Cannot Prove, where the Physicist Carolo Rovelli writes, "I am convinced, but cannot prove, that time does not exist..."

Of course, that is an inversion of the popular conviction, also inherently unprovable, that time does exist.

No great physicist me, but there is information out there to support the suggestion that makes for interesting (and, the deeper you go, baffling) reading.

P
Upward Spiral

Halfway

Joined
02 Aug 04
Moves
8702
Clock
06 Jan 10
Vote Up
Vote Down

Originally posted by DrKF
Of course, plenty of respected thinkers (in mathematics and physics, as well as philosophy) will tell you that time does not exist...

I first came accross the notion in the pop-science book What We Believe But Cannot Prove, where the Physicist Carolo Rovelli writes, "I am convinced, but cannot prove, that time does not exist..."

Of course, that is ...[text shortened]... support the suggestion that makes for interesting (and, the deeper you go, baffling) reading.
Do you remember the reason he gave for his conviction?

F

Joined
11 Nov 05
Moves
43938
Clock
06 Jan 10
Vote Up
Vote Down

Originally posted by DrKF
I first came accross the notion in the pop-science book What We Believe But Cannot Prove, where the Physicist Carolo Rovelli writes, "I am convinced, but cannot prove, that time does not exist..."
He will, given time.

D
incipit parodia

Joined
01 Aug 07
Moves
46580
Clock
06 Jan 10
Vote Up
Vote Down

Originally posted by Palynka
Do you remember the reason he gave for his conviction?
Sadly, no - and I think the book is in storage in London.

The Edge has a piece where he expands, if only a little, though:

"I am convinced, but cannot prove, that time does not exist. I mean that I am convinced that there is a consistent way of thinking about nature, that makes no use of the notions of space and time at the fundamental level. And that this way of thinking will turn out to be the useful and convincing one.

I think that the notions of space and time will turn out to be useful only within some approximation. They are similar to a notion like "the surface of the water" which looses meaning when we describe the dynamics of the individual atoms forming water and air: if we look at very small scale, there isn't really any actual surface down there. I am convinced space and time are like the surface of the water: convenient macroscopic approximations, flimsy but illusory and insufficient screens that our mind uses to organize reality.

In particular, I am convinced that time is an artifact of the approximation in which we disregard the large majority of the degrees of freedom of reality. Thus "time" is just the reflection of our ignorance."

http://www.edge.org/q2005/q05_2.html

He then goes on to say that "I am also convinced, but cannot prove, that there are no objects, but only relations." 🙂

Cookies help us deliver our Services. By using our Services or clicking I agree, you agree to our use of cookies. Learn More.