The Universe, Infinity And Qm

[petrushkagoogol]

If the Universe can be expressed as a wave-function, then the current state of the Universe

can be perceived by a human, who implicitly collapses the wave-function.

 

If the Universe were truly infinite, then it would have a wave-function that is perpetual and uncollapsable, since the very act of collapsing it would render it a finite limit.

 

Since the Universe is perceived by humans, who by their observation ascribe limits to it,

the Universe would be infinite only if those who perceive it don't exist.

 

This leads us to the astounding conclusion that the Universe is infinite, only if humans don't exist !!!

 

Is this as bizarre as it seems or pure baloney ?

[exchemist]

 

If the Universe can be expressed as a wave-function, then the current state of the Universe

can be perceived by a human, who implicitly collapses the wave-function.

 

If the Universe were truly infinite, then it would have a wave-function that is perpetual and uncollapsable, since the very act of collapsing it would render it a finite limit.

 

Since the Universe is perceived by humans, who by their observation ascribe limits to it,

the Universe would be infinite only if those who perceive it don't exist.

 

This leads us to the astounding conclusion that the Universe is infinite, only if humans don't exist !!!

 

Is this as bizarre as it seems or pure baloney ?

 

Yes quantum woo is very fashionable. But it is still woo. 

 

1) You can't express the universe as a wave function.  

 

2) And wave functions collapse due to interaction of the QM entities concerned: it is nothing to do with humanity. 

[CraigD]

If the Universe can be expressed as a wave-function, then the current state of the Universe

can be perceived by a human, who implicitly collapses the wave-function.

I disagree with this claim. What you are describing, the measurement of the current state of the entire universe, is nonlocal, which isn’t allowed by quantum mechanics, because QM includes Relativity. That is, it allows measurements, which collapse the wave function, to be performed only on locations within a sphere with radius c t, where c is the speed of light, and t is the duration of the measurement.

 

If the Universe were truly infinite, then it would have a wave-function that is perpetual and uncollapsable, since the very act of collapsing it would render it a finite limit.

The wave function of the universe gives a value for any point in space, regardless of whether the greatest distance between, say, photons originating from early in the universe’s history, is finite or infinite. So I would describe the wave function to be infinite, regardless of any quality of the universe.

 

Since the Universe is perceived by humans, who by their observation ascribe limits to it,

the Universe would be infinite only if those who perceive it don't exist.

Because we are capable of perceiving only a limited amount of information, our perception of the universe is certainly limited. However, I don’t think this implies that the universe would be infinite if humans, or similar biological organisms, didn’t exist.

 

This leads us to the astounding conclusion that the Universe is infinite, only if humans don't exist !!!

I think it’s important to be precise in defining what we mean by “universe” in the present context, and that we should define it as the observable universe, which occupies a sphere of about 10⁸ ly (10²⁷ m).

 

Whether anything exists outside of this volume is an interesting question, but since no measurement of it can be made at present, not immediately important.

 

The observable universe, has a finite volume, mass, and energy. Less obviously, its phase space is finite (In his recent and controversial Cycles of Time, Penrose estimates about [math]10^{10^{123}}[/math]). So, in every meaningful sense I can think of, the universe is finite, regardless of whether we are in it or not.

 

Is this as bizarre as it seems or pure baloney ?

I think Interpretations of quantum mechanics are bizarre, and what many people write about them baloney, but that the subject itself holds some of the most important questions existent.

 

The largest source of confusion comes, I think, from the idea that consciousness, human or other, plays a role in the evolution of the wave function – a view I call “quantum mysticism”. Some of the best physicists and philosophers have flirted with to wholly embraced this idea. But, in my thinking, what we label consciousness is itself a physical process, so not qualitatively outside of physical law. I can’t prove, but strongly suspect that wave function collapse happens in isolated systems with far fewer actual particles than any quantum mystic would intuitively accept has “consciousness”. The concept of consciousness, I think, is useful in neuropsychology and computer science, but worse than useless in physics. The concept, or rather, the failure to understand it adequately, has been, I think, damaging to physics.

[OceanBreeze]

 

2) And wave functions collapse due to interaction of the QM entities concerned: it is nothing to do with humanity. 

 

 

I’m not entirely sure of that. I am posting my limited understanding in the hope you will correct me so that I learn something.

 

My understanding of the mathematics:  all waves,, including purely classical ones like water waves,  have a "spread" relation: ΔkΔx >= 1/2. That says that the spread (Δ) in the wave-vector (k, sort of the inverse of the wavelength) times the spread in position (x) is greater than or equal to 1/2.

 

The classical wave must have spreads in both these attributes, just as you can easily picture for water waves. And these spreads in position and wave-vector are real, persistent things that can be seen visually.

 

Quantum waves, though, when they're "observed" or "measured" we don't see the full spread that was there in the wave. If you set up apparatus to measure x, you see an output that has a very narrow range of x, even if the input is a big spread of x. Likewise if you measure k, the output has a narrow range of k.  It's as if the wave-function "collapsed" in a way influenced by the type of measurement made.

 

When we say the wave function has collapsed, what we mean is either the spread (delta)  in the wave vector or the delta in position becomes narrower when measured than it was before being measured and what it collapses to cannot be predicted. It is random in that the collapsed state is not determined by any prior state. That is the quantum uncertainty.

 

So, wave-function collapse does not imply the function disappears, or if it was infinite, that it becomes finite. All that happens is the function changes in such a way as the spreads become narrower than before being measured. If the wave-function was infinite before being measured, it will still be infinite after being measured. “Collapsed” does not imply that it disappears, only changes to a different state.

 

But any measurement, as far as I know, will require some conscious entity to do the measuring. To me, that does imply that humans, or some other conscious beings, are needed to collapse the wave-function. I don’t see how it can happen without a conscious measurement.

 

I think this is what Einstein was referring to with his remark to Abraham Pais:

“Einstein suddenly stopped, turned to me and asked whether I really believed that the moon exists only when I look at it.”

 

So, to put it simply, although the moon is not there when nobody looks, it acts as if it is.

 

Do you think that is true?

[exchemist]

I’m not entirely sure of that. I am posting my limited understanding in the hope you will correct me so that I learn something.

 

My understanding of the mathematics:  all waves,, including purely classical ones like water waves,  have a "spread" relation: ΔkΔx >= 1/2. That says that the spread (Δ) in the wave-vector (k, sort of the inverse of the wavelength) times the spread in position (x) is greater than or equal to 1/2.

 

The classical wave must have spreads in both these attributes, just as you can easily picture for water waves. And these spreads in position and wave-vector are real, persistent things that can be seen visually.

 

Quantum waves, though, when they're "observed" or "measured" we don't see the full spread that was there in the wave. If you set up apparatus to measure x, you see an output that has a very narrow range of x, even if the input is a big spread of x. Likewise if you measure k, the output has a narrow range of k.  It's as if the wave-function "collapsed" in a way influenced by the type of measurement made.

 

When we say the wave function has collapsed, what we mean is either the spread (delta)  in the wave vector or the delta in position becomes narrower when measured than it was before being measured and what it collapses to cannot be predicted. It is random in that the collapsed state is not determined by any prior state. That is the quantum uncertainty.

 

So, wave-function collapse does not imply the function disappears, or if it was infinite, that it becomes finite. All that happens is the function changes in such a way as the spreads become narrower than before being measured. If the wave-function was infinite before being measured, it will still be infinite after being measured. “Collapsed” does not imply that it disappears, only changes to a different state.

 

But any measurement, as far as I know, will require some conscious entity to do the measuring. To me, that does imply that humans, or some other conscious beings, are needed to collapse the wave-function. I don’t see how it can happen without a conscious measurement.

 

I think this is what Einstein was referring to with his remark to Abraham Pais:

“Einstein suddenly stopped, turned to me and asked whether I really believed that the moon exists only when I look at it.”

 

So, to put it simply, although the moon is not there when nobody looks, it acts as if it is.

 

Do you think that is true?

I'm admittedly a bit rusty on all this but my understanding has always been that any measurement of a QM entity involves causing that entity to interact with a measuring apparatus (involving light or matter) in some way. No "observer" observes a QM entity directly, after all. The interaction collapses the wave function because the state of the QM entity is changed by the interaction, i.e the previous wave function no longer describes its state. 

 

I do not think it is true that, in the double slit experiment, the dots on the screen disappear when the experimenter goes out to get a cup of coffee. That way lies madness, it seems to me. But I suppose some people might rationalise it thus: 

 

There was a young man who said, "God

must find it exceedingly odd

when he finds that this tree

just ceases to be

when there's no one about in the quad."

 

"Dear Sir, your astonishment's odd.

I am always about in the quad,

and that's why this tree

continues to be,

Since observed by,

yours faithfully,

God." 

 

 

As for QM uncertainty, surely this is just the result of non-commuting operators, not to do with the measurement process per se? 

 

But I'm interested by your use of classical wave analogy. Your k seems to be a wavenumber, i.e. no of waves per unit length, is that right?

Edited December 20, 2016 by exchemist

[OceanBreeze]

I'm admittedly a bit rusty on all this but my understanding has always been that any measurement of a QM entity involves causing that entity to interact with a measuring apparatus (involving light or matter) in some way. No "observer" observes a QM entity directly, after all. The interaction collapses the wave function because the state of the QM entity is changed by the interaction, i.e the previous wave function no longer describes its state. 

Yes, logically that must be true; it is the interactions of the measuring apparatus (such as shining a light on an electron) that causes the wave to collapse, and not the conscious intent of the observer who is shining the light.

However, there is the confounding fact that the only outcomes of such interactions that we are aware of, are the interactions that we observe! So separating the observer out of the equation seems impossible.

 

 

I do not think it is true that, in the double slit experiment, the dots on the screen disappear when the experimenter goes out to get a cup of coffee. That way lies madness, it seems to me.

 

 

Yes, but it seems there are quite a few physicists who choose that path!

 

Consider John Wheeler, and his delayed choice experiment.

"The surprising implications of the original delayed-choice experiment led Wheeler to the conclusion that "no phenomenon is a phenomenon until it is an observed phenomenon", which is a very radical position. Wheeler famously said that the "past has no existence except as recorded in the present", and that the Universe does not "exist, out there independent of all acts of observation". :eek:

 

 

 

 

As for QM uncertainty, surely this is just the result of non-commuting operators, not to do with the measurement process per se? 

 

 

 

I was hoping you would tell me.  

 

But I'm interested by your use of classical wave analogy. Your k seems to be a wavenumber, i.e. no of waves per unit length, is that right?

 

 

Yes, technically it is a vector, with both magnitude and direction,.

[sluggo]

The "wave function" only has meaning to a human, since it's the product of  the mind. The mind is like an image processing machine, creating and analyzing images. Obviously the image is not the subject of the image. The weakness in perception (reality confined to the mind), is believing the mental constructs are the reality.

Has anyone ever seen an orbit?

[exchemist]

Yes, logically that must be true; it is the interactions of the measuring apparatus (such as shining a light on an electron) that causes the wave to collapse, and not the conscious intent of the observer who is shining the light.

However, there is the confounding fact that the only outcomes of such interactions that we are aware of, are the interactions that we observe! So separating the observer out of the equation seems impossible.

 

 

 

Yes, but it seems there are quite a few physicists who choose that path!

 

Consider John Wheeler, and his delayed choice experiment.

"The surprising implications of the original delayed-choice experiment led Wheeler to the conclusion that "no phenomenon is a phenomenon until it is an observed phenomenon", which is a very radical position. Wheeler famously said that the "past has no existence except as recorded in the present", and that the Universe does not "exist, out there independent of all acts of observation". :eek:

 

 

 

 

 

 

I was hoping you would tell me.  

 

 

Yes, technically it is a vector, with both magnitude and direction,.

OK. I find the uncertainty principle easiest to visualise (which proper physicists would already tell me is a flaky way to approach things)  in terms of Δp.Δx >/= h bar/2 while bearing in mind de Broglie's relation p=h/λ, by which momentum is proportional to frequency. The square mod amplitude of the wave function gives the probability density - and integrating this over an area of space gives the probability of the entity being detected in that space - or the proportion of its time it spends there, if one thinks of it as a particle.  

 

For an unconstrained QM entity to be located in a defined region of space requires a wavefunction that is a Fourier series of superposed waves with different frequencies, such that they interfere constructively in only a defined region. But that means there is a spread in momentum. The more accurately the postion is known the less is known about the momentum. Conversely a monochromatic wavefunction would have an exact momentum, but would have amplitude spread throughout space, i.e. position would be completely indeterminate.

 

The commuting/non-commuting operator approach is too mathematical for me these days - I'd have to look it all up  - but is equivalent. What I recall , qualitatively, of this is that In the operator formalism there is an operator for every physical observable, which operates on the state function and returns an exact value of the observable if the state function is an eigenfunction of the operator. To measure two observables simultaneously, the state function has to be an eigenfunction of both operators at once. If the operators don't commute, it won't be and then one gets a spread of values.  

 

It seems to me that neither of these demands consciousness on the part of an observer. And anyway, what does consciousness mean, in this context? Would Schroedinger's cat, looking at the detector, count? It would see the signal, but it would have no idea what it signified. Would a mouse? Or an insect? It seems to me one can go down a deep rabbit hole with this sort of thinking and never come out.

Edited December 20, 2016 by exchemist

[exchemist]

 

The "wave function" only has meaning to a human, since it's the product of  the mind. The mind is like an image processing machine, creating and analyzing images. Obviously the image is not the subject of the image. The weakness in perception (reality confined to the mind), is believing the mental constructs are the reality.

Has anyone ever seen an orbit?

 

Yes it is all only a model of reality, we should always have that caveat in mind I agree. But the aim of the model is always to get as close to reality as we can, and thus pushing it to the point of breakdown is a legitimate form of enquiry.  

[petrushkagoogol]

OK. I find the uncertainty principle easiest to visualise (which proper physicists would already tell me is a flaky way to approach things)  in terms of Δp.Δx >/= h bar/2 while bearing in mind de Broglie's relation p=h/λ, by which momentum is proportional to frequency. The square mod amplitude of the wave function gives the probability density - and integrating this over an area of space gives the probability of the entity being detected in that space - or the proportion of its time it spends there, if one thinks of it as a particle.  

 

For an unconstrained QM entity to be located in a defined region of space requires a wavefunction that is a Fourier series of superposed waves with different frequencies, such that they interfere constructively in only a defined region. But that means there is a spread in momentum. The more accurately the postion is known the less is known about the momentum. Conversely a monochromatic wavefunction would have an exact momentum, but would have amplitude spread throughout space, i.e. position would be completely indeterminate.

 

The commuting/non-commuting operator approach is too mathematical for me these days - I'd have to look it all up  - but is equivalent. What I recall , qualitatively, of this is that In the operator formalism there is an operator for every physical observable, which operates on the state function and returns an exact value of the observable if the state function is an eigenfunction of the operator. To measure two observables simultaneously, the state function has to be an eigenfunction of both operators at once. If the operators don't commute, it won't be and then one gets a spread of values.  

 

It seems to me that neither of these demands consciousness on the part of an observer. And anyway, what does consciousness mean, in this context? Would Schroedinger's cat, looking at the detector, count? It would see the signal, but it would have no idea what it signified. Would a mouse? Or an insect? It seems to me one can go down a deep rabbit hole with this sort of thinking and never come out.

 

OK. I find the uncertainty principle easiest to visualise (which proper physicists would already tell me is a flaky way to approach things)  in terms of Δp.Δx >/= h bar/2 while bearing in mind de Broglie's relation p=h/λ, by which momentum is proportional to frequency. The square mod amplitude of the wave function gives the probability density - and integrating this over an area of space gives the probability of the entity being detected in that space - or the proportion of its time it spends there, if one thinks of it as a particle.  

 

For an unconstrained QM entity to be located in a defined region of space requires a wavefunction that is a Fourier series of superposed waves with different frequencies, such that they interfere constructively in only a defined region. But that means there is a spread in momentum. The more accurately the postion is known the less is known about the momentum. Conversely a monochromatic wavefunction would have an exact momentum, but would have amplitude spread throughout space, i.e. position would be completely indeterminate.

 

The commuting/non-commuting operator approach is too mathematical for me these days - I'd have to look it all up  - but is equivalent. What I recall , qualitatively, of this is that In the operator formalism there is an operator for every physical observable, which operates on the state function and returns an exact value of the observable if the state function is an eigenfunction of the operator. To measure two observables simultaneously, the state function has to be an eigenfunction of both operators at once. If the operators don't commute, it won't be and then one gets a spread of values.  

 

It seems to me that neither of these demands consciousness on the part of an observer. And anyway, what does consciousness mean, in this context? Would Schroedinger's cat, looking at the detector, count? It would see the signal, but it would have no idea what it signified. Would a mouse? Or an insect? It seems to me one can go down a deep rabbit hole with this sort of thinking and never come out.

 

Here is what I infer from the discussions so far :

1. The Universe can be represented by a wave-function
2. The wave-function is infinite.
3. Human perception is limited by a sphere of radius c. (locality).
4. Superposition of finite perception on an infinite matrix results in a snapshot of the Universe at any instant which is totally subjective, and more importantly finite.
5. This means consciousness is woven into our understanding of the Universe.
6. QM means that we can infact fit in an infinite concept into our limited thinking.

[exchemist]

 

Here is what I infer from the discussions so far :

1. The Universe can be represented by a wave-function
2. The wave-function is infinite.
3. Human perception is limited by a sphere of radius c. (locality).
4. Superposition of finite perception on an infinite matrix results in a snapshot of the Universe at any instant which is totally subjective, and more importantly finite.
5. This means consciousness is woven into our understanding of the Universe.
6. QM means that we can infact fit in an infinite concept into our limited thinking.

 

You are emphatically not justified in making any of these inferences, from the discussion on this thread. This is just quantum woo. 

 

You don't seem to be interested in engaging with the objections that have been raised. I conclude that you have a quasi-religious view on this which brooks no disagreement.

[OceanBreeze]

OK. I find the uncertainty principle easiest to visualise (which proper physicists would already tell me is a flaky way to approach things)  in terms of Δp.Δx >/= h bar/2 while bearing in mind de Broglie's relation p=h/λ, by which momentum is proportional to frequency. The square mod amplitude of the wave function gives the probability density - and integrating this over an area of space gives the probability of the entity being detected in that space - or the proportion of its time it spends there, if one thinks of it as a particle.  

 

For an unconstrained QM entity to be located in a defined region of space requires a wavefunction that is a Fourier series of superposed waves with different frequencies, such that they interfere constructively in only a defined region. But that means there is a spread in momentum. The more accurately the postion is known the less is known about the momentum. Conversely a monochromatic wavefunction would have an exact momentum, but would have amplitude spread throughout space, i.e. position would be completely indeterminate.

 

The commuting/non-commuting operator approach is too mathematical for me these days - I'd have to look it all up  - but is equivalent. What I recall , qualitatively, of this is that In the operator formalism there is an operator for every physical observable, which operates on the state function and returns an exact value of the observable if the state function is an eigenfunction of the operator. To measure two observables simultaneously, the state function has to be an eigenfunction of both operators at once. If the operators don't commute, it won't be and then one gets a spread of values.  

 

 

OK. That is in agreement with my understanding of things also. But please leave Fourier series out of this! I still have traumatic memories of going through the learning process on that! :wacko:

 

 

 

 

 

It seems to me that neither of these demands consciousness on the part of an observer. And anyway, what does consciousness mean, in this context? Would Schroedinger's cat, looking at the detector, count? It would see the signal, but it would have no idea what it signified. Would a mouse? Or an insect? It seems to me one can go down a deep rabbit hole with this sort of thinking and never come out.

 

 

That seems to be the safe and sane view, but it just might be the road that leads to an ultimate truth must pass through the valley of the mad. I would not risk going down that road myself, but some people (with extremely strong minds) do.

 

 

 

According to Donald D. Hoffman it is conscious agents all the way down.

[OceanBreeze]

You are emphatically not justified in making any of these inferences, from the discussion on this thread. This is just quantum woo. 

 

You don't seem to be interested in engaging with the objections that have been raised. I conclude that you have a quasi-religious view on this which brooks no disagreement.

 

Lighten up, dude. This is all juju anyway!

[petrushkagoogol]

You are emphatically not justified in making any of these inferences, from the discussion on this thread. This is just quantum woo. 

 

You don't seem to be interested in engaging with the objections that have been raised. I conclude that you have a quasi-religious view on this which brooks no disagreement.

 

I beg to differ in a way..... Consciousness is a state of activation of the nervous system....possibly multiple active synapses that constitute measurement. Nervous system activation does not in any way either support or oppose a religious or quasi - religious viewpoint. The mind is to be visualized as a measuring apparatus much like a telescope or microscope..... 

[exchemist]

I beg to differ in a way..... Consciousness is a state of activation of the nervous system....possibly multiple active synapses that constitute measurement. Nervous system activation does not in any way either support or oppose a religious or quasi - religious viewpoint. The mind is to be visualized as a measuring apparatus much like a telescope or microscope..... 

If you engage with the responses, rather than simply making assertions, we can have a discussion.

 

If not, Happy Christmas.

[DrKrettin]

If not, Happy Christmas.

 

... and a Merry New Year

[Maine farmer]

I beg to differ in a way..... Consciousness is a state of activation of the nervous system....possibly multiple active synapses that constitute measurement. Nervous system activation does not in any way either support or oppose a religious or quasi - religious viewpoint. The mind is to be visualized as a measuring apparatus much like a telescope or microscope..... 

I would be more inclined to think of the mind as an interpreter of the data fed into it from the senses.  Do we directly observe the universe with our mind, or does our mind create a representation of the universe from data fed into it?  Our interpretations of the data could be wrong to some degree, yet just good enough for us to function.