Is time an illusion?

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Offline Ęthelwulf

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Re: Is time an illusion?
« Reply #50 on: 21/03/2012 06:50:08 »
Perhaps this will enlighten you

http://meopemuk2.blogspot.co.uk/2006/07/is-there-observable-of-time.html

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Offline Nizzle

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Re: Is time an illusion?
« Reply #51 on: 21/03/2012 09:03:53 »
The biggest fall I seem to be seeing right now, is people making

Time = Change

Time does not necesserily mean change at all. In fact, if anyone can follow the math of Julian Barbour, he shows you can deal with real observable things and omit time from the equations. Change can happen with real observables, the way physics should be.

You are correct: Time does not equal Change, just as length does not equal metre or volume does not equal m3

But it's still a physical quantity for me. One of the base physical quantities even, together with Length, Mass, Temperature, Amount of Substance, Electric Current and Luminous Intensity, and I'm backed up by the International System of Units! See here.

If this doesn't convince you I'm wasting my energy.

EDIT: Btw, if Barbour can eliminate Time from his equations to demonstrate 'Change', then how does he demonstrates 'Rate of Change'?
« Last Edit: 21/03/2012 09:09:19 by Nizzle »
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Offline Ęthelwulf

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Re: Is time an illusion?
« Reply #52 on: 21/03/2012 10:29:46 »
It may be defined by a physical but time is not a real artefact of physical manifestations which arise in physics as an observable. Please read the link provided.

Anyway, this change without time, what are you wanting me to do, take you through Barbour's math or something?

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Offline Ęthelwulf

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Re: Is time an illusion?
« Reply #53 on: 21/03/2012 10:34:13 »
Or rate of change specifically I see... He doesn't define that if I remember correctly. But I don't see your point. Many rate's of change are algebraicly created without any time.

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Offline imatfaal

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Re: Is time an illusion?
« Reply #54 on: 21/03/2012 10:57:01 »
Aethelwulf and others, 

Can we have fewer implications of lack of knowledge and less condescension?  Let's keep this friendly.

Thanks
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Offline yor_on

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Re: Is time an illusion?
« Reply #55 on: 24/03/2012 16:37:09 »
So tell me, what did they use to write their hypotheses in?
Were they in SpaceTime doing it.

As they refute time?
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Offline yor_on

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Re: Is time an illusion?
« Reply #56 on: 24/03/2012 16:40:19 »
You need a arrow for most of the science we built. It's all about experimenting in a arrow. Or can you give me any example of a experiment ignoring the arrow? Theoretically you can ignore it, but in reality?
=

Although I agree with some of his observations. I too think it could be described as a 'static' universe from some weird point of view, as well as there is no real evidence for anything being as 'real' as the 'present'. But I also believe that there is something changing even though the changes only can be defined through history. Probability is using that 'history' to predict what may happen in a 'future', and the funny thing is that it works? Which becomes problematic if that history doesn't exist, as well as the predicted 'future'.
« Last Edit: 24/03/2012 16:48:20 by yor_on »
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Offline yor_on

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Re: Is time an illusion?
« Reply #57 on: 24/03/2012 16:55:54 »
But this is philosophy, not science, although it's very hard to differ them at time. It becomes a quagmire to define a 'now', in that as you make the definition of it, it has already passed you by. A lot of mediations is about living in the 'now', which sometimes also is called a 'time less experience', but if you experience it, how can it be 'time less'?
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Offline Bill S

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Re: Is time an illusion?
« Reply #58 on: 24/03/2012 17:10:54 »
Quote
What is 'tensed and untensed time,'?

Sorry it has taken me a while for me to get back on this - busy!

Yor-on has covered this at length, but I was not thinking of anything as complex as that.

Put simply, its more like this:

Tensed time is “now relative”; it assumes an ever moving now, which progresses towards the future, always leaving more “past” behind it.

Tensless time relates to clock time, dates etc. and is regarded as being static.  For example, 11.30 (GMT) on the 25th October 2007 is a tensless time; in relativistic terms it is an unchanging spacetime event.  In this view there is no objective passage of time. 
There never was nothing.

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Offline yor_on

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Re: Is time an illusion?
« Reply #59 on: 24/03/2012 17:51:56 »
Let me break it down as I think of it.

A event is a description of something happening, something 'real'.
Events connect through causality.
Events when looked through history becomes a logic.

That logic holds for events still not 'here' (probability)
And as QM is probability to me?
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Offline Bill S

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Re: Is time an illusion?
« Reply #60 on: 24/03/2012 18:26:00 »
Quote
Two identical clocks, one on the Earths surface and one in orbit above the Earth will show a different passage of time.  Time passing faster for the clock in orbit.

One clock "ticks" faster than the other.  We interpret that as time passing faster, but is that necessarily the case?
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Offline yor_on

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Re: Is time an illusion?
« Reply #61 on: 24/03/2012 18:33:41 »
No, it depends on how you define it.
In one whole undivided SpaceTime it will be necessary, as the twin experiment can show us.
From 'locality' the arrow is of one measure though, the same wherever you go. But to do so you will question what a SpaceTime is.
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Offline Bill S

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Re: Is time an illusion?
« Reply #62 on: 25/03/2012 02:33:39 »
It's easy to lose sight of the fact that the twin experiment is only a thought experiment.  which Terry Pratchett describes as “One that you can’t do, and which won’t work”.  :)
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Offline yor_on

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Re: Is time an illusion?
« Reply #63 on: 25/03/2012 03:31:44 »
NIST doesn't do thought experiments Bill, and they show the same effect, although minuscule (gravitational) time dilations.
They exist, and the twin experiment is correct. The question is more of what 'time' is. A geometry?
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Offline MikeS

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Re: Is time an illusion?
« Reply #64 on: 25/03/2012 08:12:12 »
NIST doesn't do thought experiments Bill, and they show the same effect, although minuscule (gravitational) time dilations.
They exist, and the twin experiment is correct. The question is more of what 'time' is. A geometry?
Yes. 
As gravity is geometry so to is time. Time has two components, the arrow and rate of passage (time dilation factor).  It is possible to have one without the other but only in combination do they constitute 'time'.  The direction of the arrow is always universal. (That is, it points in the same direction everywhere in the Universe.)  The time dilation factor is always local.

Time or more correctly space-time is the medium in which entropy increases.
If you consider a clock (any clock) to be a closed system it requires energy to power it.  This leads to an increase in entropy within that system.

Ultimately time, in a sense is a measure of the increase in entropy.
Entropy is necessary in order to measure time.  Time is necessary in order to measure entropy.

The universe and everything it contains is trying to reach a more stable state.  That state is approached by loosing useful energy which is an increase in entropy.  So the ultimate ground state of the Universe would be zero useful energy.  At which point time would cease to exist. (Time being infinitely dilated)

'Time is what allows things to happen but stops everything from happening all at once'.
« Last Edit: 25/03/2012 08:29:23 by MikeS »

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Offline Bill S

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Re: Is time an illusion?
« Reply #65 on: 25/03/2012 20:13:42 »
Of course time dilation is real and has been measured both in terms of gravity and air travel; but what was really being measured?  Surely, what was being measured was the rate at which measuring devices operate. 
There never was nothing.

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Offline MikeS

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Re: Is time an illusion?
« Reply #66 on: 26/03/2012 06:08:32 »
Of course time dilation is real and has been measured both in terms of gravity and air travel; but what was really being measured?  Surely, what was being measured was the rate at which measuring devices operate. 

Yes and that's what we call time.
A measuring device (clock) measures the passage of local time.  But not all localities have the same passage of time, so not all clocks agree.

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Offline Ęthelwulf

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Re: Is time an illusion?
« Reply #67 on: 26/03/2012 06:25:22 »
Of course time dilation is real and has been measured both in terms of gravity and air travel; but what was really being measured?  Surely, what was being measured was the rate at which measuring devices operate. 

Yes and that's what we call time.
A measuring device (clock) measures the passage of local time.  But not all localities have the same passage of time, so not all clocks agree.

Clocks, minutes, seconds... maybe even hours to centuries all man-made concepts. Time is an illusion that we have wrapped ourselves in. Time is a construction. An invention.

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Offline Geezer

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Re: Is time an illusion?
« Reply #68 on: 26/03/2012 07:17:02 »

Clocks, minutes, seconds... maybe even hours to centuries all man-made concepts. Time is an illusion that we have wrapped ourselves in. Time is a construction. An invention.


Ah right! But if there is no such thing as time, what is it that is controlling how matter decays? I could be wrong, but I'm pretty sure uranium does not turn into lead as a consequence of human willpower.
There ain'ta no sanity clause, and there ain'ta no centrifugal force ęther.

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Offline Ęthelwulf

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Re: Is time an illusion?
« Reply #69 on: 26/03/2012 09:29:25 »

Clocks, minutes, seconds... maybe even hours to centuries all man-made concepts. Time is an illusion that we have wrapped ourselves in. Time is a construction. An invention.


Ah right! But if there is no such thing as time, what is it that is controlling how matter decays? I could be wrong, but I'm pretty sure uranium does not turn into lead as a consequence of human willpower.

Not quite sure of your point, apart from a frivolous question on human will power. What does the radiation, of an atom supposed to do with conversation at large? I have heard, that radiation processes are used in arguements against a predeterministic universe since they purport to truely random processes.

To this I turn our attention to zeno effect. It is completely possible to make your system deterministic by the power of observation. A scientist in the lab can make so-called weak measurements on the system and freeze it in time, making it completely predictable. This is because you are suspending the time evolution operator.

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Offline Geezer

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Re: Is time an illusion?
« Reply #70 on: 26/03/2012 10:07:49 »
Not quite sure of your point, apart from a frivolous question on human will power. What does the radiation, of an atom supposed to do with conversation at large? I have heard, that radiation processes are used in arguements against a predeterministic universe since they purport to truely random processes.

To this I turn our attention to zeno effect. It is completely possible to make your system deterministic by the power of observation. A scientist in the lab can make so-called weak measurements on the system and freeze it in time, making it completely predictable. This is because you are suspending the time evolution operator.

Nothing frivolous about it.
 
If it is not time, please explain what it is that causes differences in atomic decay.
There ain'ta no sanity clause, and there ain'ta no centrifugal force ęther.

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Offline Ęthelwulf

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Re: Is time an illusion?
« Reply #71 on: 26/03/2012 10:19:47 »
Not quite sure of your point, apart from a frivolous question on human will power. What does the radiation, of an atom supposed to do with conversation at large? I have heard, that radiation processes are used in arguements against a predeterministic universe since they purport to truely random processes.

To this I turn our attention to zeno effect. It is completely possible to make your system deterministic by the power of observation. A scientist in the lab can make so-called weak measurements on the system and freeze it in time, making it completely predictable. This is because you are suspending the time evolution operator.

Nothing frivolous about it.
 
If it is not time, please explain what it is that causes differences in atomic decay.

Not sure what ''will-power'' has to do with this. Anyway, if equations help describe our world, then equations can describe changes quite well without time. Time is just a tool. Being ommitted from the equations does not stop us from using equations which don't require it.

Take Barbours work seriously. His equation can describe physical processes without time. His equation is a good example, because you might as well get comfortable with it. This is what GR predicts. A timeless universe.

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Offline Bill S

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Re: Is time an illusion?
« Reply #72 on: 26/03/2012 21:15:24 »
Quote from: MikeS
Yes and that's what we call time.

That sums up the situation perectly!  There is, or feels as though there should be, this something.  We can't see it, hear it, touch it, smell it or even agree as to what it might be.  However, life seems to make a lot more sense with it than without it.   

I'm with St Augustine on this one:  "What then is time? If no one asks me, I know;
if I wish to explain it to someone who asks, I know not."
There never was nothing.

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Offline dkeizer05

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Re: Is time an illusion?
« Reply #73 on: 27/03/2012 03:05:11 »

Seriously dude, go learn some physics before you make statements you can't support. Time should not be physical. Just because it is part of an understanding Minkowski made years and years ago that by treating it as a dimension has left physics following a wrong path - a deluded idea that perhaps time is also physical, that it is part of the manifold we call space. Sure, calculationally-wise, time is very useful when thought of as a dimension. Other than that, it has no physical appearance. Time is not an observable. It is not tangible.
Is speed a tangible?

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Offline MikeS

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Re: Is time an illusion?
« Reply #74 on: 27/03/2012 07:10:38 »
Of course time dilation is real and has been measured both in terms of gravity and air travel; but what was really being measured?  Surely, what was being measured was the rate at which measuring devices operate. 

Yes and that's what we call time.
A measuring device (clock) measures the passage of local time.  But not all localities have the same passage of time, so not all clocks agree.

Clocks, minutes, seconds... maybe even hours to centuries all man-made concepts. Time is an illusion that we have wrapped ourselves in. Time is a construction. An invention.

They are all man named in as much as they are measures of time as referenced by the Earth and its orbit around the sun. 

Time is real as Geezer has pointed out.

Any type of clock whether it be atomic, electronic, mechanical spring driven, mechanical gravity driven, atomic decay, speed of light etc. will all keep the same time in the same local time frame.  Likewise identical clocks in a different local time frame where the gravitational potential is different will all keep pace with each other but show a time dilation effect relative to the first set of clocks.

Quite obviously both sets of clocks are measuring something.
They are measuring local time.

If they are not measuring local time, what are they measuring?


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Offline Ęthelwulf

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Re: Is time an illusion?
« Reply #75 on: 27/03/2012 08:22:01 »

Seriously dude, go learn some physics before you make statements you can't support. Time should not be physical. Just because it is part of an understanding Minkowski made years and years ago that by treating it as a dimension has left physics following a wrong path - a deluded idea that perhaps time is also physical, that it is part of the manifold we call space. Sure, calculationally-wise, time is very useful when thought of as a dimension. Other than that, it has no physical appearance. Time is not an observable. It is not tangible.
Is speed a tangible?

Observables, real tangible properties which can be measured are provided by Hermitian Matrices. I will leave it to you as a task to find out what uses Hermitian Matrices.

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Offline imatfaal

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Re: Is time an illusion?
« Reply #76 on: 27/03/2012 10:24:10 »
Aethelwulf - please lose the superior attitude and keep it friendly. 


Seriously dude, go learn some physics before you make statements you can't support. Time should not be physical. Just because it is part of an understanding Minkowski made years and years ago that by treating it as a dimension has left physics following a wrong path - a deluded idea that perhaps time is also physical, that it is part of the manifold we call space. Sure, calculationally-wise, time is very useful when thought of as a dimension. Other than that, it has no physical appearance. Time is not an observable. It is not tangible.
Is speed a tangible?

Observables, real tangible properties which can be measured are provided by Hermitian Matrices. I will leave it to you as a task to find out what uses Hermitian Matrices.

On your above comment properties are not "provided by Hermitian Matrices" - that is well and truly putting the quantum mechanical cart before the horse.  Dynamic variables can be associated with a hermitian operator - which is not the same thing at all.

In quantum mechanics every variable (position, momentum,  angular momentum, spin, energy, and many tothers) is able to be represented by a Hermitian operator that can be mathematically manipulated in a way to describe an action on the state of the system and the eigenvalues of which will correspond to the possible values that the dynamical variable can take.   I would be interested on your take on momentum and energy which are well known and well used variables and associated hermitian operators - and how an absence of time would effect them.
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Offline Ęthelwulf

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Re: Is time an illusion?
« Reply #77 on: 27/03/2012 11:55:51 »
Aethelwulf - please lose the superior attitude and keep it friendly. 


Seriously dude, go learn some physics before you make statements you can't support. Time should not be physical. Just because it is part of an understanding Minkowski made years and years ago that by treating it as a dimension has left physics following a wrong path - a deluded idea that perhaps time is also physical, that it is part of the manifold we call space. Sure, calculationally-wise, time is very useful when thought of as a dimension. Other than that, it has no physical appearance. Time is not an observable. It is not tangible.
Is speed a tangible?

Observables, real tangible properties which can be measured are provided by Hermitian Matrices. I will leave it to you as a task to find out what uses Hermitian Matrices.

On your above comment properties are not "provided by Hermitian Matrices" - that is well and truly putting the quantum mechanical cart before the horse.  Dynamic variables can be associated with a hermitian operator - which is not the same thing at all.

In quantum mechanics every variable (position, momentum,  angular momentum, spin, energy, and many tothers) is able to be represented by a Hermitian operator that can be mathematically manipulated in a way to describe an action on the state of the system and the eigenvalues of which will correspond to the possible values that the dynamical variable can take.   I would be interested on your take on momentum and energy which are well known and well used variables and associated hermitian operators - and how an absence of time would effect them.

This has nothing to do with being superior. This has to do with being right. Why spurt off something which makes no sense? I am shrugging my shoulders here.

Anyway, observables, things that we can measure are Hermitian Matrices. This is well-established in quantum mechanics, that is, they are always real. Let's just cover what it implies.

You must first check to see if [tex]a[/tex] and [tex]b[/tex] are complex conjugates of each other, [tex]<a|b>[/tex]. A less obvious case might be [tex]<b|M|a>[/tex]. Take [tex]M[/tex] multiplying it with the ket vector gives a new row vector. Take the inner product with [tex]<b|[/tex] and it spits out a number. We might say then that [tex]|a>[/tex] is acting complex conjugate [tex]<a|M \dagger|b>[/tex] where all rows and columns have been interchanged. Properly conjugated one has the form

[tex]<b|M|a> = <a|M\dagger|b>[/tex]

However if it is Hermitian then

[tex]<b|M|a> = <a|M|b>^{*}[/tex]

where the dagger notation is removed. If we have our [tex]a=b[/tex] then a wee snippet to mention that it is simply the expectation [tex]<a|M|a>[/tex]. So I am unsure what it is really you have an objection about. My statement is very scientific.

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Offline yor_on

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Re: Is time an illusion?
« Reply #78 on: 30/03/2012 20:42:38 »
Let us play out your idea a little Wulf :)

Assume that 'the arrow of time' is a component that can be ignored for a complete description. Then assume that you measure a 'photon path'. You find it to exist as it must through your weak measurements, which here will be amassed statistics as far as I see.

Then that 'path' is no path at all, it's the probability of a path. And the fact that you also see weak measurements as 'eliminating time', if I got it right, then must become a statement of that light not moving at all. And if it is so, which I sometimes think too, what about the 'paths' not taken?
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Offline Ęthelwulf

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Re: Is time an illusion?
« Reply #79 on: 30/03/2012 21:01:17 »
Let us play out your idea a little Wulf :)

Assume that 'the arrow of time' is a component that can be ignored for a complete description. Then assume that you measure a 'photon path'. You find it to exist as it must through your weak measurements, which here will be amassed statistics as far as I see.

Then that 'path' is no path at all, it's the probability of a path. And the fact that you also see weak measurements as 'eliminating time', if I got it right, then must become a statement of that light not moving at all. And if it is so, which I sometimes think too, what about the 'paths' not taken?

I mentioned weak measurements before because someone mentioned atomic clocks radiating away energy. I mentioned weak measurements because the zeno effect can in fact freeze the evolution of systems.

Anyway, as for paths, we describe them in relativity with worldlines. Wordlines don't make a distinction of past and future - perhaps just as important, you can view worldines as static.

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Offline Pmb

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Re: Is time an illusion?
« Reply #80 on: 30/03/2012 23:00:16 »
This thread is too long to read all of it so I'm starting to read it here.

Question: There was an article in Scientific American entitled Is Time an Illusion? Would you like to read it? If so then I'll take the time to upload it to the web and modify my website to accomodate it.

Pete

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Offline JP

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Re: Is time an illusion?
« Reply #81 on: 30/03/2012 23:02:54 »
Aethelwulf - please lose the superior attitude and keep it friendly. 


Seriously dude, go learn some physics before you make statements you can't support. Time should not be physical. Just because it is part of an understanding Minkowski made years and years ago that by treating it as a dimension has left physics following a wrong path - a deluded idea that perhaps time is also physical, that it is part of the manifold we call space. Sure, calculationally-wise, time is very useful when thought of as a dimension. Other than that, it has no physical appearance. Time is not an observable. It is not tangible.
Is speed a tangible?

Observables, real tangible properties which can be measured are provided by Hermitian Matrices. I will leave it to you as a task to find out what uses Hermitian Matrices.

On your above comment properties are not "provided by Hermitian Matrices" - that is well and truly putting the quantum mechanical cart before the horse.  Dynamic variables can be associated with a hermitian operator - which is not the same thing at all.

In quantum mechanics every variable (position, momentum,  angular momentum, spin, energy, and many tothers) is able to be represented by a Hermitian operator that can be mathematically manipulated in a way to describe an action on the state of the system and the eigenvalues of which will correspond to the possible values that the dynamical variable can take.   I would be interested on your take on momentum and energy which are well known and well used variables and associated hermitian operators - and how an absence of time would effect them.

This has nothing to do with being superior. This has to do with being right. Why spurt off something which makes no sense? I am shrugging my shoulders here.

Anyway, observables, things that we can measure are Hermitian Matrices. This is well-established in quantum mechanics, that is, they are always real. Let's just cover what it implies.

You must first check to see if [tex]a[/tex] and [tex]b[/tex] are complex conjugates of each other, [tex]<a|b>[/tex]. A less obvious case might be [tex]<b|M|a>[/tex]. Take [tex]M[/tex] multiplying it with the ket vector gives a new row vector. Take the inner product with [tex]<b|[/tex] and it spits out a number. We might say then that [tex]|a>[/tex] is acting complex conjugate [tex]<a|M \dagger|b>[/tex] where all rows and columns have been interchanged. Properly conjugated one has the form

[tex]<b|M|a> = <a|M\dagger|b>[/tex]

However if it is Hermitian then

[tex]<b|M|a> = <a|M|b>^{*}[/tex]

where the dagger notation is removed. If we have our [tex]a=b[/tex] then a wee snippet to mention that it is simply the expectation [tex]<a|M|a>[/tex]. So I am unsure what it is really you have an objection about. My statement is very scientific.

One should be careful not to assume that something must be an observable to be measured.  You can measure arrival times or duration times quite well, even though you can't write "time" as a Hermitian operator.  There's been a lot of recent advances in understanding how real-world measurements work in quantum mechanics (not the idealized types usually talked about in textbooks), and this has led to the idea of a positive operator-valued measure: http://en.wikipedia.org/wiki/POVM 

There's a lot of math there, but the gist is that you can define useful operators that measure different time properties of a quantum state.  These operators aren't unique, nor are they necessarily Hermitian, but within the POVM framework, they describe measurements of those time properties.

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Offline Ęthelwulf

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Re: Is time an illusion?
« Reply #82 on: 31/03/2012 00:57:49 »
Well, if we are taking about something which can be measured, then we are talking about Eigenstates here. It seems quite simple enough that time is not an observable - it is not something we can see directly.

Assuming time can be measured because we can ''measure durations'' to me, is like falling back on that illusion we call time and once again projecting it on the world we tend to measure just because we ''think it exists objectively.'' There is however, no real evidence for this. In fact, I have found in my own studies that time more or less does not even exist within the modern framework of relativity. Physics also reshaped the idea that somehow time has a flow; which it doesn't.

Time isn't a ''state'' which comes about from a measurement. Hence again, it is not an observable.

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Offline Geezer

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Re: Is time an illusion?
« Reply #83 on: 31/03/2012 01:25:35 »
Time isn't a ''state'' which comes about from a measurement. Hence again, it is not an observable.

States don't come about by measurement. States are observed through measurement. States exist whether you measure them or not.
 
Time isn't a state, but time determines the state of everything.
There ain'ta no sanity clause, and there ain'ta no centrifugal force ęther.

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Offline acecharly

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Re: Is time an illusion?
« Reply #84 on: 31/03/2012 01:45:09 »
I think time is odd. I think its an illusion and also not an illusion. My mind tells me that every state of the universe is fixed. We see a continual rolling of these states which gives us a perception of change in the universe just like a film rolling through a projector showing individual frames. Our brains perceive this as a moving picture or "time". I believe time is simply a change of the state of the universe. If every particle in the universe were to stop momenterily then time would stop until some particle made a first move. My concern though is how to describe one of these frames if you dont use time i.e. between each keystroke i make on this keyboard for example how many frames have been taken? is it the combined number of every particle of matter moving through space between 2 events?

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Offline Ęthelwulf

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Re: Is time an illusion?
« Reply #85 on: 31/03/2012 02:06:17 »
Time isn't a ''state'' which comes about from a measurement. Hence again, it is not an observable.

States don't come about by measurement. States are observed through measurement. States exist whether you measure them or not.
 
Time isn't a state, but time determines the state of everything.

I disagree.

According to the fundamental interpretation of quantum mechanics, objects exist in a superpositioning of states. Only upon a measurement can you pull a quantum system out of this superpositioning and create well-defined states.

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Offline Ęthelwulf

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Re: Is time an illusion?
« Reply #86 on: 31/03/2012 02:07:44 »
Time isn't a ''state'' which comes about from a measurement. Hence again, it is not an observable.

States don't come about by measurement. States are observed through measurement. States exist whether you measure them or not.
 
Time isn't a state, but time determines the state of everything.

As for time is not a state, but determines states, who could argue with that? Still don't make it an observable.

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Offline Ęthelwulf

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Re: Is time an illusion?
« Reply #87 on: 31/03/2012 02:10:27 »
I think time is odd. I think its an illusion and also not an illusion. My mind tells me that every state of the universe is fixed. We see a continual rolling of these states which gives us a perception of change in the universe just like a film rolling through a projector showing individual frames. Our brains perceive this as a moving picture or "time". I believe time is simply a change of the state of the universe. If every particle in the universe were to stop momenterily then time would stop until some particle made a first move. My concern though is how to describe one of these frames if you dont use time i.e. between each keystroke i make on this keyboard for example how many frames have been taken? is it the combined number of every particle of matter moving through space between 2 events?

If I was to believe in time, it would require some serious changes... past and future could not exist. Only an everlasting present moment, and inside the present sphere physical change occurs. I would also have to teach myself to believe that there is no flow to time as well. It does not extend from any past, nor to any future, because nothing exists in the past and nothing exists in the future.

But hey, I don't need to believe any of that, because I am convinced time is an invention and we keep attaching to the physical world outside, erreneously I should add.

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Offline Geezer

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Re: Is time an illusion?
« Reply #88 on: 31/03/2012 02:19:12 »

As for time is not a state, but determines states, who could argue with that? Still don't make it an observable.


So the changes in state that we observe are the result of what exactly? Or are you saying changes in state are an illusion too?
There ain'ta no sanity clause, and there ain'ta no centrifugal force ęther.

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Offline acecharly

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Re: Is time an illusion?
« Reply #89 on: 31/03/2012 02:30:07 »
I think time is odd. I think its an illusion and also not an illusion. My mind tells me that every state of the universe is fixed. We see a continual rolling of these states which gives us a perception of change in the universe just like a film rolling through a projector showing individual frames. Our brains perceive this as a moving picture or "time". I believe time is simply a change of the state of the universe. If every particle in the universe were to stop momenterily then time would stop until some particle made a first move. My concern though is how to describe one of these frames if you dont use time i.e. between each keystroke i make on this keyboard for example how many frames have been taken? is it the combined number of every particle of matter moving through space between 2 events?

If I was to believe in time, it would require some serious changes... past and future could not exist. Only an everlasting present moment, and inside the present sphere physical change occurs. I would also have to teach myself to believe that there is no flow to time as well. It does not extend from any past, nor to any future, because nothing exists in the past and nothing exists in the future.

But hey, I don't need to believe any of that, because I am convinced time is an invention and we keep attaching to the physical world outside, erreneously I should add.

You say..."in the present sphere physical change occurs" from which points do you believe change occurs though? We could assume that from the big bang to now could be that sphere or a kettle goin from cold to boiling. For change to occur we must have moved to the next sphere. Time is a consequence of physical change without it the universe would be impossible id have thought because all matter would be in every state it has ever been in and ever will be in if that makes sense. Isnt time similar to gravity? it exists as a consequence of warped space like a side effect.

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Offline Ęthelwulf

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Re: Is time an illusion?
« Reply #90 on: 31/03/2012 02:36:28 »
This thread is too long to read all of it so I'm starting to read it here.

Question: There was an article in Scientific American entitled Is Time an Illusion? Would you like to read it? If so then I'll take the time to upload it to the web and modify my website to accomodate it.

Pete

To save you time, here is the article:
 <link redacted pending copyright check>
« Last Edit: 02/04/2012 13:18:46 by imatfaal »

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Offline Ęthelwulf

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Re: Is time an illusion?
« Reply #91 on: 31/03/2012 02:37:50 »

As for time is not a state, but determines states, who could argue with that? Still don't make it an observable.


So the changes in state that we observe are the result of what exactly? Or are you saying changes in state are an illusion too?

Change is not synonymous with time. Changes can be decribed without a time evolution - these are just special ways of treating a new emerging physics.

The article, actually describes this above in my previous post. It is a good read, makes all the arguements I have made.

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Offline Ęthelwulf

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Re: Is time an illusion?
« Reply #92 on: 31/03/2012 02:39:33 »
I think time is odd. I think its an illusion and also not an illusion. My mind tells me that every state of the universe is fixed. We see a continual rolling of these states which gives us a perception of change in the universe just like a film rolling through a projector showing individual frames. Our brains perceive this as a moving picture or "time". I believe time is simply a change of the state of the universe. If every particle in the universe were to stop momenterily then time would stop until some particle made a first move. My concern though is how to describe one of these frames if you dont use time i.e. between each keystroke i make on this keyboard for example how many frames have been taken? is it the combined number of every particle of matter moving through space between 2 events?

If I was to believe in time, it would require some serious changes... past and future could not exist. Only an everlasting present moment, and inside the present sphere physical change occurs. I would also have to teach myself to believe that there is no flow to time as well. It does not extend from any past, nor to any future, because nothing exists in the past and nothing exists in the future.

But hey, I don't need to believe any of that, because I am convinced time is an invention and we keep attaching to the physical world outside, erreneously I should add.

You say..."in the present sphere physical change occurs" from which points do you believe change occurs though? We could assume that from the big bang to now could be that sphere or a kettle goin from cold to boiling. For change to occur we must have moved to the next sphere. Time is a consequence of physical change without it the universe would be impossible id have thought because all matter would be in every state it has ever been in and ever will be in if that makes sense. Isnt time similar to gravity? it exists as a consequence of warped space like a side effect.

Time is a consequence of a subliminal feeling of some of time passing. To me, time is not a consequence of change, because time does not exist. Change does.

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Offline acecharly

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Re: Is time an illusion?
« Reply #93 on: 31/03/2012 02:39:47 »

As for time is not a state, but determines states, who could argue with that? Still don't make it an observable.


So the changes in state that we observe are the result of what exactly? Or are you saying changes in state are an illusion too?

Haha i do love mindbogglers like this.....isnt it kind of yes and no here? the state changes but at the same time its a different state not the same state that we started with...

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Offline acecharly

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Re: Is time an illusion?
« Reply #94 on: 31/03/2012 02:46:02 »
Hmmmm it seems a little bit of splitting hairs is taking place when you say you dont believe in time but you believe in change its a different word describing the same thing.

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Offline Ęthelwulf

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Re: Is time an illusion?
« Reply #95 on: 31/03/2012 02:50:40 »
Hmmmm it seems a little bit of splitting hairs is taking place when you say you dont believe in time but you believe in change its a different word describing the same thing.

Well, I think there are serious problems if one cannot identify a difference between change and time. Will time still pass if an atom is frozen from evolving when measured (zeno effect)? See, an atom may be frozen from evolving by radiating away energy. Frozen in the sense no change happens, but we normally don't assume time itself has stopped, only the time evolution.

Change and time are really not describing the same things.

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Offline acecharly

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Re: Is time an illusion?
« Reply #96 on: 31/03/2012 03:06:13 »
If we differentiate between time and change and go with change, the 2 states must be totally independant i.e the atom from one changed state to the other must be 2 totally different atoms almost another universe with an atom that is similar to the one from the previous universe though in a slightly different state and/or position and each and every change observed must also be this way and as we all observe these same changes we must all be moving into the same universe as each other unless their are an infinite amount of changes and possibilities of change taking place in an infinite amount of universes.

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Offline JP

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Re: Is time an illusion?
« Reply #97 on: 31/03/2012 03:22:05 »
Well, if we are taking about something which can be measured, then we are talking about Eigenstates here. It seems quite simple enough that time is not an observable - it is not something we can see directly.

Assuming time can be measured because we can ''measure durations'' to me, is like falling back on that illusion we call time and once again projecting it on the world we tend to measure just because we ''think it exists objectively.'' There is however, no real evidence for this. In fact, I have found in my own studies that time more or less does not even exist within the modern framework of relativity. Physics also reshaped the idea that somehow time has a flow; which it doesn't.

Time isn't a ''state'' which comes about from a measurement. Hence again, it is not an observable.

Perhaps you should take a look at what POVM entails before dismissing it out of hand? 

It's basically reformulating the concept of measurement in QM in terms of operators that get you real-valued results.  The theory has showed (successfully) that the result of a measurement is not necessarily the result of applying a self-adjoint operator to your state.  Even in this theory, there are still no "time eigenstates," but that's beside the point--we know that we can measure arrival times and this theory explains how.

It's also been a lot of use in quantum information theory, and is a pretty active area of research. 

Here's a good link explaining how it differs from the more traditional view of measurables: http://www.springerlink.com/content/pmafpr8xt0cbve9b/fulltext.pdf

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Offline yor_on

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Re: Is time an illusion?
« Reply #98 on: 31/03/2012 08:12:20 »
Time isn't a ''state'' which comes about from a measurement. Hence again, it is not an observable.

States don't come about by measurement. States are observed through measurement. States exist whether you measure them or not.
 
Time isn't a state, but time determines the state of everything.

I disagree.

According to the fundamental interpretation of quantum mechanics, objects exist in a superpositioning of states. Only upon a measurement can you pull a quantum system out of this superpositioning and create well-defined states.

And what do you do that measurement in?
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Offline yor_on

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Re: Is time an illusion?
« Reply #99 on: 31/03/2012 08:19:35 »
Thanks JP, I will certainly read it for one :)

And in a way the arrow becomes 'hair splitting' as we have no certain definition of it. To have a 'change' there is needed a mechanism for something to change. That mechanism is the arrow. Then the question becomes, as I'm starting to wonder and Wulf it seems, as well as some others here, if the arrow only can be observed on 'what changes' or if there is a arrow for something not changing too?

If you like me think that the arrow is a very local process then if there is no change locally the arrow is 'suspended' as I see it now. If you on the other hand conceive of SpaceTime as being 'one whole thing' then it becomes trickier.
« Last Edit: 31/03/2012 08:21:10 by yor_on »
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