a timely question

[Brian W (Brian)]

Just too many cloudy nights and too much time on my hands so here goes...

I believe that it is fair to say that -change- gives one the perception of time.

Is it also fair to say that -change- creates time.

One possible end of the universe scenario has everything expanding and slowing down until absolute zero is reached and then everything just stops. (I know way over simplified)

Would that mean time stops as well?

Brian

[CraigS]

Time is our way of measuring changing motion.

I can't see how we can measure this, if we don't exist.

It is also relative, and observers elsewhere may perceive its passage differently from us.

Quantum fluctuations and symmetry changes may have given rise to the Big Bang, (under presently accepted theory), … so if quantum fluctuations and symmetry changes are all there is left at 'the end', then there will still be changes in motion .. but no one will ever be there to observe it !

Neat stuff !!

Cheers

[renormalised (Carl)]

So Craig, if no one is there to observe it, does it exist??

There's a question for you

Remember, the link between observer and the observed in quantum physics.

[CraigS]

Originally Posted by renormalised

So Craig, if no one is there to observe it, does it exist??

There's a question for you

It doesn't get much mooter ...(??).. er .. more moot, than that question !!

Moot .. moot !!


I reckon I'll leave that one to Brian !!


Cheers

[Brian W (Brian)]

Thank you Craig finally a question I can answer... comparative 'more moot'... superlative 'most moot'.

But I am not sure it is a moot point.

If time only exists as an observable recordable experience then time cannot exist without an observer.

Now my niche is more philosophical than scientifical so here I will put the clock back in the scientists court (if the following question makes sense from a scientific perspective);

Was there -time- in whatever existed to cause the Big bang?

I realize how loose a question I just asked but hey, it is still monsoon season.
Brian

[astroron (Ron)]

Surely Time is only now or in the past, there is no future time till you get there
I think time started with the Big Bang,so there could have been no time before it

[CraigS]

Brian … (thanks for the pointers on the 'moot' thing .. I hate words coming from a legal system origin, in science discussions. )

Ok ..

Originally Posted by Brian_W

Was there -time- in whatever existed to cause the Big bang?

Theory tells us what must have happened during very small time intervals immediately following the BB. So time after the BB isn't a problem for theoretical Physics.

The BB origin was a singularity as 'predicted' by running the clock backwards in our present day theoretical, mathematically described laws of physics. We have no mathematical framework to describe what happens before a singularity. So there is only conjecture about what may/may not have been, prior to the singularity.

(Aside: interestingly, we also have no framework to describe the conditions of anything smaller than Planck size).

On this basis, scientists make the statement that 'time began at the BB and probably didn't exist prior to it'. Interestingly, I have heard Hawking say that gravity existed, prior to the BB .. which I think, confuses the issue a lot. I'll put his words aside for now .. he probably had some reason for making this statement but I don't know what it was.

Hope this helps.
Others: corrections welcome, if I've misinterpreted something incorrectly.

Cheers

[renormalised (Carl)]

Originally Posted by CraigS

It doesn't get much mooter ...(??).. er .. more moot, than that question !!

Moot .. moot !!


I reckon I'll leave that one to Brian !!


Cheers

It's not a moot point, Craig. It strikes right at the heart of quantum physics. If something isn't observed, then it can be said to be in all states simultaneously. It's only when an observation is made that the waveform of the observed object/process collapses to the value the observer assigns to the observation (just by the act of making the observation).

If there is no observer to make the observation in the first place, how can universal simultaneity even be said to exist, since that simultaneity is predicated on the existence of both...only that an observation hasn't been made which gives the observed its form. That which is being observed also observes the observer...so before the observer makes an observation of the observed, the observer is also in all possible states.

[bojan]

Originally Posted by renormalised

the observer is also in all possible states.

... and "observer" doesn't necessarily mean us (humans, alive sentient organisms etc)..
"Observer" may be another particle, affected by the "observed" event.
The observation can be conducted using automated, non-sentient equipment (computers, robots.. artificial intelligence....)

So, my conclusion from the above is - time MUST exist without us... as long as there is more than one single particle in the universe.

[CraigS]

Ok .. so the question was:

So Craig, if no one is there to observe it, does it exist??

To which I (rather arrogantly) commented that it was a moot point. I should have said “moot point for me”).

Then I passed it over to Brian to answer, as I interpreted it as a philosophical question, for which he is very well suited to continue the discussion.

Brian replied:

Originally Posted by Brian

But I am not sure it is a moot point.

Which I respect .. as my comment was only an opinion.
His other answer was:

Originally Posted by Brian

If time only exists as an observable recordable experience then time cannot exist without an observer.

So now Carl says:

Originally Posted by renormalised

Its not a moot point

Fair enough ... I have no problems with that.

Summarising from my own understanding, it can be said that for the case of a ‘no existence’ state, (in the traditional sense), for the observer and the observed, then it can also be said that both can also ‘exist’ in all possible states, simultaneously. (Quantum Mechanics perspective).

Special Relativity (SP) argues that simultaneity is not universal. Observers in different frames of reference can have different perceptions about whether a given pair of events, happened at the same, or different times (depending on their frame of reference). (Aside: there is one particular case where this statement is not apparent, however). There is no physical basis for preferring one observer’s observation over the other’s.

But simultaneity may not exist in the first place, ie: if there are no observers. So, the case where ‘simultaneity is {Edit: oops .. just removed the 'not'} universal’, has not been ruled out (ie: see the first paragraph).

Hence the QM perspective has 'more to say' about Brian’s case/scenario at ‘the end’.

I'm not sure whether it says anything about the original question:
Ie: does it (time) exist ?

Is the above a reasonable interpretation ?

Cheers

[Brian W (Brian)]

Originally Posted by CraigS

Ok .. so the question was:


I'm not sure whether it says anything about the original question:
Ie: does it (time) exist ?

Is the above a reasonable interpretation ?

Cheers

Actually Craig, the original question was not 'does time exist' but rather 'would time exist without change?'

It is my left handed crazy canuck way of trying to get to the essential necessities for there to be time.

This question is of course based upon the entirely possibly erroneous belief that time is a 'result' rather than a 'cause'
Brian

Brian

[CraigS]

Originally Posted by Brian W

Actually Craig, the original question was not 'does time exist' but rather 'would time exist without change?'

Yes Brian that was your original question .. but Carl hammered us (me) with another mind-bender … which is what I was referring to in my previous post.

It is my left handed crazy canuck way of trying to get to the essential necessities for there to be time.

This question is of course based upon the entirely possibly erroneous belief that time is a 'result' rather than a 'cause'.

… a result of the observer's existence, eh ?
.. rather than the cause of the observer's existence ?

Cheers

[Karls48 (Karl)]

Back to original post. To me – if the time was created by Big Bang then the BB could not happen. The singularity that caused BB would be static without passage of the time. Therefore I think that there must be some kind of not relativistic Universal time in the Universe.
Best analogy of BB singularity we can see today is possibly a black hole. If BH swallows a star what happen to the space and the time that was occupied by the star. Does the total volume of the space in our Universe diminish by the volume of the star that is crushed to singularity? Inside of BH dimensions supposed to be 0 therefore the time does not exist. And yet BH is supposed eventually to evaporate or explode. It is because the time still flows outside of BH and allows the interaction with what should be static object. This is one of the reasons why I believe that there must be kind Time that flow and exists outside of our Universe.

[renormalised (Carl)]

Originally Posted by bojan

... and "observer" doesn't necessarily mean us (humans, alive sentient organisms etc)..
"Observer" may be another particle, affected by the "observed" event.
The observation can be conducted using automated, non-sentient equipment (computers, robots.. artificial intelligence....)

So, my conclusion from the above is - time MUST exist without us... as long as there is more than one single particle in the universe.

Actually, following this logic, you only need one particle to exist for time to be present because the observer and the observed can be one and the same.

[sjastro]

Originally Posted by CraigS

Yes Brian that was your original question .. but Carl hammered us (me) with another mind-bender … which is what I was referring to in my previous post.

Here is another mind bender, time is not an observable in Quantum Mechanics.

Now I need to try to explain it without using maths.

Regards

Steven

[CraigS]

Originally Posted by sjastro

Here is another mind bender, time is not an observable in Quantum Mechanics.

Now I need to try to explain it without using maths.

Regards

Steven

Oh man .. there goes everything up in a puff of mathematical logic !!

Damn !!

I'll wait for an explanation of that one !!

Cheers

[renormalised (Carl)]

Ok....here's another "mind bender"....what is time???

Does it actually have a physical reality or is it nothing more than an illusion.

Remember, you can't argue this on the basis of SR alone, since SR is a limited case to begin with, or by GR because it's limited to existence on a macroscopic scale (usually very large scales), and quantum physics would ultimately say that time is nothing.

So what is it??

[bojan]

Originally Posted by renormalised

Actually, following this logic, you only need one particle to exist for time to be present because the observer and the observed can be one and the same.

Errr.. is that so?

We define time as "something" that happens/elapses between two events, one happening at the "observed" object (particle) and "observer" (affected particle).

I think we need at least two particles (observer is the reference) to be able to measure time (to determine if the event associated with object happened before or after the event(s) happening on the observer.

[renormalised (Carl)]

Here Steven, this might save you the time (pun intended)

http://timeandquantummechanics.com/overview/

[CraigS]

Originally Posted by renormalised

Ok....here's another "mind bender"....what is time???

Does it actually have a physical reality or is it nothing more than an illusion.

Remember, you can't argue this on the basis of SR alone, since SR is a limited case to begin with, or by GR because it's limited to existence on a macroscopic scale (usually very large scales), and quantum physics would ultimately say that time is nothing.

So what is it??

I notice that whilst questions about it are valid, answers clearly, may not be supportable in Science.

Definition of 'moot': of little or no practical value or meaning; purely academic !!

.. The only value or meaning it has, is what we associate with it.



Ok … so attempting to answer the question doesn't work …

… I'm going to become religious .. … and its all Brian's fault …
... (just kidding, Brian .. its not your fault .. and there's nothing wrong with religion .. )

Cheers