Questions About Time

[surreptitious57]

Is time a dimension without any past or present or future? Does one move through it at the rate of one second per second?

That is to say the same rate as the second hand ticking on a clock is also the same rate one experiences time in real time?

Is there a reason why the three arrows of time [ biological / thermodynamic / cosmological ] move in only the one direction?

Why is the Second Law Of Thermodynamics the one major one that is actually non reversible from a temporal perspective?

Is time what space expands into? What happens to time once it passes the event horizon? Does it speed up or slow down?

Or stay just the same? How is it possible for a photon not to experience time but travel through it? Has time always existed?

[ajb]

You have asked a lot of questions...

 

Is time a dimension without any past or present or future?

We have the notion of coordinate time and proper time. The coordinate time is a 'dimension' (okay, poorly stated) while the proper time is the time that an observers clock measures.

 

Is there a reason why the three arrows of time [ biological / thermodynamic / cosmological ] move in only the one direction?

Good question and nobody knows the answer.

 

Why is the Second Law Of Thermodynamics the one major one that is actually non reversible from a temporal perspective?

No idea. But it does seem that several of the other arrows really can be reduced to the thermodynamic arrow. Maybe this arrow is the real fundamental one, but again no one is really sure.

 

Is time what space expands into?

As in the expansion of the Universe? If so then no. I am not sure if you have something else in mind here.

 

What happens to time once it passes the event horizon? Does it speed up or slow down?

Or stay just the same?

You mean the proper time as measured by an in falling observer? Then nothing happens.

 

How is it possible for a photon not to experience time but travel through it?

Photons do not have a rest frame and so the notion of proper time makes no sense. You have to be careful with 'the photon's point of view'.

 

Has time always existed?

No idea.

[michel123456]

Is time a dimension without any past or present or future?

Theory says Time is a dimension. Future past & present are direction on this dimension that are relative to the observer. Napoleon is somewhere on our past, we are somewhere on Napoleon's future

Does one move through it

I believe so, yes, but some other members may disagree on that.

at the rate of one second per second?

No. A rate of seconds by seconds (s/s) has no meaning. No more meaning that a meters by meters for distances. A distance has units meters, and time has units seconds. Point. There is no rate.

That is to say the same rate as the second hand ticking on a clock is also the same rate one experiences time in real time?

I don't understand that.

Is there a reason why the three arrows of time [ biological / thermodynamic / cosmological ] move in only the one direction?

Well, there are only 2 directions available, so for 3 elements it should not be a surprise that the 2 of them have the same direction.

Why is the Second Law Of Thermodynamics the one major one that is actually non reversible from a temporal perspective?

Equations of thermodynamics are time reversible IIRC. The 2nd law is empirical, it describes an observation, so it should not a surprise that this observation is accurate.

Is time what space expands into?

I don't think so. Space by itself is an outdated concept. The correct concept is Spacetime.

What happens to time once it passes the event horizon?

If time is part of Spacetime, then the question is what happen to spacetime once it passes the event horizon. And since Spacetime is a receptacle, my gut feeling is that nothing happens.

Does it speed up or slow down?

Or stay just the same?

Time cannot "speed up" nor "slow down", these are wrong concepts similar to the concept of rate you introduced earlier.

How is it possible for a photon not to experience time but travel through it?

That ressembles your earlier question. Indeed, does a photon "travel" through time?

Has time always existed?

That is a tricky question because the concept itself of "existence" is directly linked to time.

[studiot]

 

Time cannot "speed up" nor "slow down",

 

Isn't that what is observed by an observer in relative motion to the observed?

 

 

That ressembles your earlier question. Indeed, does a photon "travel" through time?

 

 

I think the question arises because for lightspeed relative motion time dilation is infinite or time 'stands still'.

There is some 'lively discussion' about what his means in technical circles.

[michel123456]

Isn't that what is observed by an observer in relative motion to the observed?

Time is not a speed.

I think the question arises because for lightspeed relative motion time dilation is infinite or time 'stands still'.

There is some 'lively discussion' about what his means in technical circles.

I have been challenged here on this forum when I tried to explain my POV of things "traveling" through time. The word "travel" or "motion" through time is the question here.

IOW do we "move" through time?

Some other members say that no, we don't "move".

If I am not abused, Theory states that we "extend" through time.

Edited September 7, 2015 by michel123456

[studiot]

Time is not a speed.

I have been challenged here on this forum when I tried to explain my POV of things "traveling" through time. The word "travel" or "motion" through time is the question here.

IOW do we "move" through time?

Some other members say that no, we don't "move".

If I am not abused, Theory states that we "extend" through time.

 

So you are arguing semantics or terminology, not the effects themselves, which is (I think) what the OP wanted to discuss.

 

If you can agree that the effects themselves (often called time dilation in special relativity) occur and what to call them then the discussion can proceed.

 

Surely this is better than just telling someone they are wrong because they used the wrong word?

Edited September 7, 2015 by studiot

[swansont]

!

Moderator Note

The hijack on the topic of QM and ESP has been split.

 

http://www.scienceforums.net/topic/91039-hijack-from-questions-about-time/

I have been challenged here on this forum when I tried to explain my POV of things "traveling" through time. The word "travel" or "motion" through time is the question here.

 

!

Moderator Note

This is not your thread, so advancing your POV is inappropriate here. Stick to mainstream science for as much as the OP that is science rather than philosophy.

[michel123456]

(...)Does one move through it?(...)How is it possible for a photon not to experience time but travel through it?(...)

This quote above from the OP.

 

The OP has introduced the concept of "travel" through time.

So you are arguing semantics or terminology, not the effects themselves, which is (I think) what the OP wanted to discuss.

 

If you can agree that the effects themselves (often called time dilation in special relativity) occur and what to call them then the discussion can proceed.

 

Surely this is better than just telling someone they are wrong because they used the wrong word?

I disagree it is about semantics.

 

It is about the difference between an object experiencing motion and the receptacle in which motion happens. An object can speed up or decelerate. The receptacle, called Spacetime, is like a block engraved in Pendelikon marble. The concepts of time dilation and length contraction are about the measurement from one Frame of Reference to another. Time & Space do not dilate & contract just because someone else in another FOR is taking a measurement. If ten observers in 10 FoRs are taking measurements of a single moving object, they will obtain 10 different dilations & contractions. That does not mean time & space dilate & contract in 10 different ways, it means that each observer will take a different measurement and will be able to know exactly what the 9 other observers will measure.

------------

Sorry, the correct is "pentelic marble".

Edited September 8, 2015 by michel123456

[studiot]

This quote above from the OP.

 

The OP has introduced the concept of "travel" through time.

I disagree it is about semantics.

 

It is about the difference between an object experiencing motion and the receptacle in which motion happens. An object can speed up or decelerate. The receptacle, called Spacetime, is like a block engraved in Pendelikon marble. The concepts of time dilation and length contraction are about the measurement from one Frame of Reference to another. Time & Space do not dilate & contract just because someone else in another FOR is taking a measurement. If ten observers in 10 FoRs are taking measurements of a single moving object, they will obtain 10 different dilations & contractions. That does not mean time & space dilate & contract in 10 different ways, it means that each observer will take a different measurement and will be able to know exactly what the 9 other observers will measure.

 

So how are you not offering absolute time and absolute space?

[michel123456]

 

So how are you not offering absolute time and absolute space?

It is my understanding of established physics. Not considering the cosmological expansion of space of course.

If I am wrong, please proceed.

 

Anyway this is not about absolute time and absolute space. It is about relative measurements of time and space into Spacetime. When time dilates, length contracts. You cannot have the one without the other. It acts as a conservation law.

Edited September 8, 2015 by michel123456

[Strange]

You cannot have the one without the other. It acts as a conservation law.

 

That is a nice way of putting it; it is not quite a conservation law (because there is no "stuff" that is being conserved), but there is an invariant (the spacetime interval between two events).

[studiot]

I see what I wrote was ambiguous, apologies for the confusion.

 

Your post#8, specifically the 'container' implies the existence of absolute time and absolute space, both of which are forbidden by relativity.

 

So to rephrase my question

 

Why are you offering absolute time and absolute space?

[MigL]

Michel123456 ( and GR ) is saying that all events, past, present and future are 'fixed' in space-time.

I don't understand how that equates to absolute time or absolute space.

Please explain.

[kaliet]

Hi, i had (and i continue have) the same kind of questions as you, about the time-concept.

 

To properly answer your questions, man should read --- and understand --- a lot, a lot, ..., a lot of books.

 

I will try to answer, some of them, taking in account i can be wrong, but exposing different points of view, i think can help.

 

The concept of "time rate" is a key-point to understand what really time is.

 

Naturally, we must assume the validity of the General Theory of Relativity of Albert Einstein. It is approved and verified by multiple experiments.

 

To get a "value" of "time rate" we must make at least 2 measures, that is:

 

 

O1 ---> O2 AND O2 ---> O1

 

 

O1 and O2 are both "Observers", i.e., systems capable to process information.

 

 

Say t_1_2 the time measured by O1 for O2.

 

Say t_2_1 the time measured by O2 for O1.

 

 

Can you find -- mathematically -- a "time" t, such that t / t_1_2 = t / t_2_1, meaning t / t1 the "time" t modulo t1, and t / t2 the "time" t modulo t2 ?

 

Furthermore, (have) had that question a "physical" meaning, or it is only a mathematical abstraction?

 

That is, why t / t =1. My answer, it is algebra.

[neutrinosalad]

Is there a reason why the three arrows of time [ biological / thermodynamic / cosmological ] move in only the one direction?

 

Good question and nobody knows the answer.

 

Here's an interesting question to think about.

 

What if the three arrows of time move in more than one direction and that we as human beings only have capacity to perceive one of them?