C60 Interference

[Alan Grayson]

IIUC, as the temperature rises, interference in the double slit C60 experiment declines, and eventually disappears. I don't think this is really a which-way experiment because the interference disappears whether or not which-way is observed. How does this effect the collapse issue? Usually, IIUC, when interference ceases to exist, it implies collapse of the wf. So, is the C60 double slit experiment evidence for collapse of the wf? TIA, AG

[Philip Thrift]

On Monday, November 4, 2019 at 7:53:17 PM UTC-6, Alan Grayson wrote:

IIUC, as the temperature rises, interference in the double slit C60 experiment declines, and eventually disappears. I don't think this is really a which-way experiment because the interference disappears whether or not which-way is observed. How does this effect the collapse issue? Usually, IIUC, when interference ceases to exist, it implies collapse of the wf. So, is the C60 double slit experiment evidence for collapse of the wf? TIA, AG

Raising temperature - more than near absolute zero - destroys qubits' abilities to hold multiple quantum "states" at the same time.

   https://medium.com/the-quantum-authority/ice-ice-baby-why-quantum-computers-have-to-be-cold-3a7f777d9728

So I guess it is something like that.

@philipthrift

      

[smitra]

Consider the C60 moving through one or the other slit and then ending up
at some spot x on the screen. If the state of the rest of the universe
when the C60 takes on slit is |A(x)> and it is |B(x)> if another slit is
taken, then the interference pattern locally at spot x on the screen
will be proportional to Re[<A(x)|B(x)>]. So, if there is perfect which
way information for C60 that arrive in the neighborhood of spot x on the
screen, then the two environmental states will be orthogonal and the
interference will vanish.

In case of the experiment in a thermal environment, the C60 will suffer
collisions with photons. The states |A> and |B> will be different due to
these collisions, as in every such case the state the universe ends up
in will depend on which path the C60 took as the collision it suffered
when it took one path would not have happened (instead another collision
event at the another slit may have occurred). As the temperature rises,
the interference pattern will then fade away as the number of C60
molecules that passed through without interactions near the slits will
become small.

Saibal

[Brent Meeker]

On 11/5/2019 9:21 AM, smitra wrote:
> On 05-11-2019 02:53, Alan Grayson wrote:
>> IIUC, as the temperature rises, interference in the double slit C60
>> experiment declines, and eventually disappears. I don't think this is
>> really a which-way experiment because the interference disappears
>> whether or not which-way is observed. How does this effect the
>> collapse issue? Usually, IIUC, when interference ceases to exist, it
>> implies collapse of the wf. So, is the C60 double slit experiment
>> evidence for collapse of the wf? TIA, AG
>
>
> Consider the C60 moving through one or the other slit and then ending
> up at some spot x on the screen. If the state of the rest of the
> universe when the C60 takes on slit is |A(x)> and it is |B(x)> if
> another slit is taken, then the interference pattern locally at spot x
> on the screen will be proportional to Re[<A(x)|B(x)>]. So, if there is
> perfect which way information for C60 that arrive in the neighborhood
> of spot x on the screen, then the two environmental states will be
> orthogonal and the interference will vanish.
>
> In case of the experiment in a thermal environment, the C60 will
> suffer collisions with photons.

It's not collisions with photons from the environment.  The C60s are
heated in the experiment, so it is IR emission from the C60 that puts
which-way information into the environment.

> The states |A> and |B> will be different due to these collisions,

|A> and |B> are different ex hypothesi regardless of collisions or
emissions.

Brent

[Alan Grayson]

On Tuesday, November 5, 2019 at 1:11:21 PM UTC-7, Brent wrote:

On 11/5/2019 9:21 AM, smitra wrote:
> On 05-11-2019 02:53, Alan Grayson wrote:
>> IIUC, as the temperature rises, interference in the double slit C60
>> experiment declines, and eventually disappears. I don't think this is
>> really a which-way experiment because the interference disappears
>> whether or not which-way is observed. How does this effect the
>> collapse issue? Usually, IIUC, when interference ceases to exist, it
>> implies collapse of the wf. So, is the C60 double slit experiment
>> evidence for collapse of the wf? TIA, AG
>
>
> Consider the C60 moving through one or the other slit and then ending
> up at some spot x on the screen. If the state of the rest of the
> universe when the C60 takes on slit is |A(x)> and it is |B(x)> if
> another slit is taken, then the interference pattern locally at spot x
> on the screen will be proportional to Re[<A(x)|B(x)>]. So, if there is
> perfect which way information for C60 that arrive in the neighborhood
> of spot x on the screen, then the two environmental states will be
> orthogonal and the interference will vanish.
>
> In case of the experiment in a thermal environment, the C60 will
> suffer collisions with photons.

It's not collisions with photons from the environment.  The C60s are
heated in the experiment, so it is IR emission from the C60 that puts
which-way information into the environment.

That's what I don't understand. If there's no detector focused on, or watching the slits, 

how can which-way information exist? All we observe is loss of interference without

which-way information. What can we conclude from this? AG

[Bruce Kellett]

I thought I had explained that in my first post on this matter. If the IR photon wavelength is short enough, detecting that photon enables one to determine which path the C60 followed, or which slit it went through. As the C60 atoms are heated up, the IR wavelengths become shorter, and we can determine which slit for a greater proportion of the photons. Hence the interference disappears gradually as the temperature increases. We do not even have to detect the IR photons -- their information is in the environment, and that is sufficient decoherence for the interference to vanish.

Bruce

[Alan Grayson]

Amazing if true. I assume the photon is emitted in random directions and, moreover, there's no observation of the slits. If so, how could this determine which-way? AG

 

As the C60 atoms are heated up, the IR wavelengths become shorter, and we can determine which slit for a greater proportion of the photons. Hence the interference disappears gradually as the temperature increases. We do not even have to detect the IR photons -- their information is in the environment, and that is sufficient decoherence for the interference to vanish.

This I previously understood. But what is the big picture take-away from this phenomenon? AG 

Bruce

[Bruce Kellett]

Simply by localizing which path the atom followed. Elementary, my dear Watson.

As the C60 atoms are heated up, the IR wavelengths become shorter, and we can determine which slit for a greater proportion of the photons. Hence the interference disappears gradually as the temperature increases. We do not even have to detect the IR photons -- their information is in the environment, and that is sufficient decoherence for the interference to vanish.

This I previously understood. But what is the big picture take-away from this phenomenon? AG 

Quantum mechanics is wonderful!

Bruce

[Brent Meeker]

On 11/5/2019 2:49 PM, Alan Grayson wrote:
>
> That's what I don't understand. If there's no detector focused on, or
> watching the slits,
> how can which-way information exist? All we observe is loss of
> interference without
> which-way information. What can we conclude from this? AG

That we don't have to possess the which-way information.  It's enough
that it exists.

Brent

[Alan Grayson]

Yes, that's how I revised my understanding of the double slit experiment. BUT Bruce says we DO get which-way information. How is that possible just based on temperature? AG 

[Brent Meeker]

He didn't say we got it.  He said it was possible to get it. Just as watching a glowing body allows you to know its trajectory.

Brent

[Alan Grayson]

I see. Then we don't need Buckyballs or heated particles, just a cloud chamber enclosing a double slit experiment with electrons being fired, and no need to look at the paths, and the interference pattern would disappear. If so, what about the deBroglie wave length for the electron and its wave like property? Does it become irrelevant to the result of the experiment? AG 

[Bruno Marchal]

On 5 Nov 2019, at 02:53, Alan Grayson <agrays...@gmail.com> wrote:

IIUC, as the temperature rises, interference in the double slit C60 experiment declines, and eventually disappears. I don't think this is really a which-way experiment because the interference disappears whether or not which-way is observed. How does this effect the collapse issue? Usually, IIUC, when interference ceases to exist, it implies collapse of the wf. So, is the C60 double slit experiment evidence for collapse of the wf? TIA, AG

My two pre views posts explained exactly this, in the non-collapse frame. It works for particles, Molecules and even macroscopic cats. The advantage of the non-collapse quantum theory is that any interaction can be counted as a measurement. So heat cannot not decrease interference, for the technical factorisation reason already explained.

Bruno

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[Philip Thrift]

On Wednesday, November 6, 2019 at 3:19:58 AM UTC-6, Bruno Marchal wrote:

On 5 Nov 2019, at 02:53, Alan Grayson <agrays...@gmail.com> wrote:

IIUC, as the temperature rises, interference in the double slit C60 experiment declines, and eventually disappears. I don't think this is really a which-way experiment because the interference disappears whether or not which-way is observed. How does this effect the collapse issue? Usually, IIUC, when interference ceases to exist, it implies collapse of the wf. So, is the C60 double slit experiment evidence for collapse of the wf? TIA, AG

My two pre views posts explained exactly this, in the non-collapse frame. It works for particles, Molecules and even macroscopic cats. The advantage of the non-collapse quantum theory is that any interaction can be counted as a measurement. So heat cannot not decrease interference, for the technical factorisation reason already explained.

Bruno

They've sent 2000-atom sized molecules through double slits.

What about sending cats?

@philipthrift 

[Bruno Marchal]

You will loss the ability to get the interference, because it is hugely more complex to isolate a cat from the environment, so its alive or dead state will be pass on you unavoidably very quickly.  See my explanation to Grayson why any (unknown) interaction of an object in a superposition state makes it logically impossible to remain in a superposition relatively to you. It uses only very elementary algebra. The quantum effect, to be exploited, require perfect isolation, which is impossible for most macroscopic object. But some “macro-superposition” have been obtained with superconducting device. In fact, superconductor is a quantum macroscopic effect.

Bruno

@philipthrift 

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[Brent Meeker]

On 11/7/2019 6:21 AM, Bruno Marchal wrote:

On 6 Nov 2019, at 10:34, Philip Thrift <cloud...@gmail.com> wrote:

On Wednesday, November 6, 2019 at 3:19:58 AM UTC-6, Bruno Marchal wrote:

On 5 Nov 2019, at 02:53, Alan Grayson <agrays...@gmail.com> wrote:

IIUC, as the temperature rises, interference in the double slit C60 experiment declines, and eventually disappears. I don't think this is really a which-way experiment because the interference disappears whether or not which-way is observed. How does this effect the collapse issue? Usually, IIUC, when interference ceases to exist, it implies collapse of the wf. So, is the C60 double slit experiment evidence for collapse of the wf? TIA, AG

My two pre views posts explained exactly this, in the non-collapse frame. It works for particles, Molecules and even macroscopic cats. The advantage of the non-collapse quantum theory is that any interaction can be counted as a measurement. So heat cannot not decrease interference, for the technical factorisation reason already explained.

Bruno

They've sent 2000-atom sized molecules through double slits.

What about sending cats?

You will loss the ability to get the interference, because it is hugely more complex to isolate a cat from the environment, so its alive or dead state will be pass on you unavoidably very quickly.  See my explanation to Grayson why any (unknown) interaction of an object in a superposition state makes it logically impossible to remain in a superposition relatively to you. It uses only very elementary algebra. The quantum effect, to be exploited, require perfect isolation, which is impossible for most macroscopic object. But some “macro-superposition” have been obtained with superconducting device. In fact, superconductor is a quantum macroscopic effect.

Aside from the isolation problems the de Broglie wavelength of a cat is extremely small so to get an interference pattern the slit and slit spacing must be correspondingly small.  The C60 experiment was only made possible by the development of the Tablot-Lau interferometer.

Brent

[Alan Grayson]

I've made this point before; the decoherence time for a cat is very very short, but how does this effect the point Schroedinger wanted to make, since the cat is in that paradoxical superposition for some short but finite duration? AG 

[Bruce Kellett]

Schrodinger did not know about decoherence. He was pointing to the absurdity of taking the SWE as representing the full story about cats.

Bruce

[Brent Meeker]

On 11/7/2019 4:13 PM, Alan Grayson wrote:

They've sent 2000-atom sized molecules through double slits.

What about sending cats?

You will loss the ability to get the interference, because it is hugely more complex to isolate a cat from the environment, so its alive or dead state will be pass on you unavoidably very quickly.  See my explanation to Grayson why any (unknown) interaction of an object in a superposition state makes it logically impossible to remain in a superposition relatively to you. It uses only very elementary algebra. The quantum effect, to be exploited, require perfect isolation, which is impossible for most macroscopic object. But some “macro-superposition” have been obtained with superconducting device. In fact, superconductor is a quantum macroscopic effect.

Aside from the isolation problems the de Broglie wavelength of a cat is extremely small so to get an interference pattern the slit and slit spacing must be correspondingly small.  The C60 experiment was only made possible by the development of the Tablot-Lau interferometer.

Brent

I've made this point before; the decoherence time for a cat is very very short, but how does this effect the point Schroedinger wanted to make, since the cat is in that paradoxical superposition for some short but finite duration? AG 

There is no paradox.  It's just some hang up you have that a cat can't be dead and alive at the same time.  It's as though your physics was stuck in the time of Aristotle and words were magic so that "Alive implies not-dead." was a law of physics instead of an axiom of logic.

In fact a moments thought will tell you that quite aside from quantum mechanics there would be no way to identify the moment of death of the cat to less than a several seconds.  It would be simply meaningless to say the cat was alive at 0913:20 and dead at 0913:21.

Brent

[Alan Grayson]

Sure, but what about the claim that the macro world is really quantum; that is, the idea that the macro world is derivable from the quantum world? AG 

[Bruce Kellett]

What about it? Do you think it can't be done?

Bruce

[Alan Grayson]

You can imagine a different experiment, without cats, with the same paradoxical result. The point of Schroedinger's thought experiment was to demonstate tHE title of this thread; that there's something wrong with the prevailing interpretation of superposition. In your view I am hung up with Aristotle? In my view, you're seduced by some quantum nonsense. AG 

[Brent Meeker]

On 11/7/2019 5:01 PM, Alan Grayson wrote:

There is no paradox.  It's just some hang up you have that a cat can't be dead and alive at the same time.  It's as though your physics was stuck in the time of Aristotle and words were magic so that "Alive implies not-dead." was a law of physics instead of an axiom of logic.

In fact a moments thought will tell you that quite aside from quantum mechanics there would be no way to identify the moment of death of the cat to less than a several seconds.  It would be simply meaningless to say the cat was alive at 0913:20 and dead at 0913:21.

Brent

You can imagine a different experiment, without cats, with the same paradoxical result. The point of Schroedinger's thought experiment was to demonstate tHE title of this thread; that there's something wrong with the prevailing interpretation of superposition. In your view I am hung up with Aristotle? In my view, you're seduced by some quantum nonsense. AG 

Prevailing when?  1927?  There is no problem in the prevailing 2019 interpretation, except in your mind because you assume that a cat cannot be in a superposition of alive/dead even for a fraction of a nano-second...because...WHY?   The radioactive atom can be in a superposition of decayed and not-decayed for a nanosecond.  Why doesn't that violate your Aristotelean logic?

Brent

[Bruce Kellett]

We have moved on somewhat in the 80-plus years since Schrodinger's thought experiment. The "prevailing view" is now different from his, so what he thought he had demonstrated is no longer particularly relevant.

Bruce

[Alan Grayson]

What's wrong with the interpretation that the radioactive atom is either decayed OR undecayed with probabilities calculated by Born's Rule? AG 

[Alan Grayson]

Fair enough. So what is the "prevailing view" now? Isn't it (in the context of Brent's last post) that a radioactive atom can be simultaneously decayed and undecayed? How is this different from the days of Schroedinger? AG 

[Bruce Kellett]

Decoherence is rapid. Schrodinger did not know about this. But the SWE predicts momentary superpositions -- at least until the environment enforces the preferred basis.

Bruce

[Alan Grayson]

7:39 PM (1 hour ago)

[Brent Meeker]

Being in the quasi-classical state of either decayed or undecayed assumes the superposition of decayed and undecayed has decohered by interaction with the environment.  The interactions that produce decoherence all proceed at less than the speed of light, so it is not instantaneous.  So the atom and the cat are no different...except the time for which one can keep them isolated from the environment.

Brent

[Alan Grayson]

Maybe isolation is an idealization which never exists in nature. That would put this issue to bed. AG 

[Alan Grayson]

Yes, I think that's right. If you imagined a particle being created, wouldn't it fail to be isolated at the moment of its creation? AG 

[Brent Meeker]

Except that isolation admits of degrees, and interactions, even at the speed of light, are not instantaneous.  The atomic nucleus is relatively isolated.  That's why the environment has no measurable effect on its half-life.

Brent

[Alan Grayson]

But once decoherence occurs, it's never reversed. It's permanent. So nothing can be isolated, not even the atomic nucleus. AG 

[Brent Meeker]

But decoherence doesn't occur at the nucleus.  It's an interaction of the nucleus with the environment.  The alpha particle or whatever tunnels out in order to interact with the Geiger counter.  But the probability of tunneling is very low per unit time. That's what I mean by "isolated", a low probability of interaction.

Brent

[Alan Grayson]

Doesn't decoherence occur when the nucleus forms? It can't form in isolation from the universe. AG 

[Alan Grayson]

And each particle constituent of the nucleus becomes entangled with the environment when it's created. I am open to criticisms, but I see this as the solution to the superposition problem. Nothing is isolated. It's just an unrealistic idealization which leads to paradoxes. AG

[Philip Thrift]

Keep in mind

The superposition property allows the particle to be in a quantum superposition of two or more quantum states at the same time. However, a "quantum state" in quantum mechanics means the probability that a system will be, for example at a position x, not that the system will actually be at position x. 

 

It does not imply that the particle itself may be in two classical states at once.

 Indeed, quantum mechanics is generally unable to assign values for properties prior to measurement at all.

https://en.wikipedia.org/wiki/Schr%C3%B6dinger_equation

@philipthrift

[Bruno Marchal]

Once the cat is alive + dead, he remains in that state for ever. I don’t see any mean to avoid this without introducing non unitary phenomena. He accessibility to interference is very short, because we can’t isolate the cat, and the wave length is very tiny (making perhaps no sense in a GR accommodation of QM), but in pure elementary QM, superposition are forever.

Bruno

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[Bruno Marchal]

Then a photon will go only through one slit, and we are back to classical mechanics, or QM + hidden variable (and FTL), etc. We need the superposition to explain the interference patterns.

Bruno

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[Alan Grayson]

On Sunday, November 10, 2019 at 5:42:50 AM UTC-7, Bruno Marchal wrote:

On 8 Nov 2019, at 01:13, Alan Grayson <agrays...@gmail.com> wrote:

On Thursday, November 7, 2019 at 12:50:21 PM UTC-7, Brent wrote:

On 11/7/2019 6:21 AM, Bruno Marchal wrote:

On 6 Nov 2019, at 10:34, Philip Thrift <cloud...@gmail.com> wrote:

On Wednesday, November 6, 2019 at 3:19:58 AM UTC-6, Bruno Marchal wrote:

On 5 Nov 2019, at 02:53, Alan Grayson <agrays...@gmail.com> wrote:

IIUC, as the temperature rises, interference in the double slit C60 experiment declines, and eventually disappears. I don't think this is really a which-way experiment because the interference disappears whether or not which-way is observed. How does this effect the collapse issue? Usually, IIUC, when interference ceases to exist, it implies collapse of the wf. So, is the C60 double slit experiment evidence for collapse of the wf? TIA, AG

My two pre views posts explained exactly this, in the non-collapse frame. It works for particles, Molecules and even macroscopic cats. The advantage of the non-collapse quantum theory is that any interaction can be counted as a measurement. So heat cannot not decrease interference, for the technical factorisation reason already explained.

Bruno

They've sent 2000-atom sized molecules through double slits.

What about sending cats?

You will loss the ability to get the interference, because it is hugely more complex to isolate a cat from the environment, so its alive or dead state will be pass on you unavoidably very quickly.  See my explanation to Grayson why any (unknown) interaction of an object in a superposition state makes it logically impossible to remain in a superposition relatively to you. It uses only very elementary algebra. The quantum effect, to be exploited, require perfect isolation, which is impossible for most macroscopic object. But some “macro-superposition” have been obtained with superconducting device. In fact, superconductor is a quantum macroscopic effect.

Aside from the isolation problems the de Broglie wavelength of a cat is extremely small so to get an interference pattern the slit and slit spacing must be correspondingly small.  The C60 experiment was only made possible by the development of the Tablot-Lau interferometer.

Brent

I've made this point before; the decoherence time for a cat is very very short, but how does this effect the point Schroedinger wanted to make, since the cat is in that paradoxical superposition for some short but finite duration? AG 

Once the cat is alive + dead, he remains in that state for ever.

Then how come we NEVER observe that state? AG

 

I don’t see any mean to avoid this without introducing non unitary phenomena. [T]he accessibility to interference is very short, because we can’t isolate the cat,

Then without interference, the superposition ceases to exist! AG

[Bruno Marchal]

On 10 Nov 2019, at 20:01, Alan Grayson <agrays...@gmail.com> wrote:

On Sunday, November 10, 2019 at 5:42:50 AM UTC-7, Bruno Marchal wrote:

On 8 Nov 2019, at 01:13, Alan Grayson <agrays...@gmail.com> wrote:

On Thursday, November 7, 2019 at 12:50:21 PM UTC-7, Brent wrote:

On 11/7/2019 6:21 AM, Bruno Marchal wrote:

On 6 Nov 2019, at 10:34, Philip Thrift <cloud...@gmail.com> wrote:

On Wednesday, November 6, 2019 at 3:19:58 AM UTC-6, Bruno Marchal wrote:

On 5 Nov 2019, at 02:53, Alan Grayson <agrays...@gmail.com> wrote:

IIUC, as the temperature rises, interference in the double slit C60 experiment declines, and eventually disappears. I don't think this is really a which-way experiment because the interference disappears whether or not which-way is observed. How does this effect the collapse issue? Usually, IIUC, when interference ceases to exist, it implies collapse of the wf. So, is the C60 double slit experiment evidence for collapse of the wf? TIA, AG

My two pre views posts explained exactly this, in the non-collapse frame. It works for particles, Molecules and even macroscopic cats. The advantage of the non-collapse quantum theory is that any interaction can be counted as a measurement. So heat cannot not decrease interference, for the technical factorisation reason already explained.

Bruno

They've sent 2000-atom sized molecules through double slits.

What about sending cats?

You will loss the ability to get the interference, because it is hugely more complex to isolate a cat from the environment, so its alive or dead state will be pass on you unavoidably very quickly.  See my explanation to Grayson why any (unknown) interaction of an object in a superposition state makes it logically impossible to remain in a superposition relatively to you. It uses only very elementary algebra. The quantum effect, to be exploited, require perfect isolation, which is impossible for most macroscopic object. But some “macro-superposition” have been obtained with superconducting device. In fact, superconductor is a quantum macroscopic effect.

Aside from the isolation problems the de Broglie wavelength of a cat is extremely small so to get an interference pattern the slit and slit spacing must be correspondingly small.  The C60 experiment was only made possible by the development of the Tablot-Lau interferometer.

Brent

I've made this point before; the decoherence time for a cat is very very short, but how does this effect the point Schroedinger wanted to make, since the cat is in that paradoxical superposition for some short but finite duration? AG 

Once the cat is alive + dead, he remains in that state for ever.

Then how come we NEVER observe that state? AG

Because the observable are defined by their possible definite outcome, and for reason already explained, macroscopic superposition decoder, that is get entangled with the environment at a very high speed. So, if you look at the cat in the a+d state, you are duplicate almost immediately into a guy seeing the cat alive + the guy seeing the cat dead, and QM explained why they cannot interact, although they might interfere themselves.

 

I don’t see any mean to avoid this without introducing non unitary phenomena. [T]he accessibility to interference is very short, because we can’t isolate the cat,

Then without interference, the superposition ceases to exist! AG

Relatively to me or you, but, in principles, they do not cease to exist, they just cease to be detectable.

Bruno

 

and the wave length is very tiny (making perhaps no sense in a GR accommodation of QM), but in pure elementary QM, superposition are forever.

Bruno

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[Bruce Kellett]

On Mon, Nov 11, 2019 at 8:37 PM Bruno Marchal <mar...@ulb.ac.be> wrote:

On 10 Nov 2019, at 20:01, Alan Grayson <agrays...@gmail.com> wrote:

 

On Sunday, November 10, 2019 at 5:42:50 AM UTC-7, Bruno Marchal wrote:

Once the cat is alive + dead, he remains in that state for ever.

Then how come we NEVER observe that state? AG

Because the observable are defined by their possible definite outcome, and for reason already explained, macroscopic superposition decoder, that is get entangled with the environment at a very high speed. So, if you look at the cat in the a+d state, you are duplicate almost immediately into a guy seeing the cat alive + the guy seeing the cat dead, and QM explained why they cannot interact, although they might interfere themselves.

That is exactly a preferred basis -- which you seem to want to deny.

Bruce

[Alan Grayson]

In the case of a radioactive atom in state |decayed> + |undecayed>, what's the justification and advantage of the interpretation that it's in both states simultaneously? AG 

[Philip Thrift]

None, since it isn't.

@philipthrift 

[smitra]

On 11-11-2019 22:44, Alan Grayson wrote:
> On Monday, November 11, 2019 at 4:35:13 AM UTC-7, Bruce wrote:
>
>> On Mon, Nov 11, 2019 at 8:37 PM Bruno Marchal <mar...@ulb.ac.be>
>> wrote:
>>
>>> On 10 Nov 2019, at 20:01, Alan Grayson <agrays...@gmail.com>
>>> wrote:
>>
>> On Sunday, November 10, 2019 at 5:42:50 AM UTC-7, Bruno Marchal
>> wrote:
>>
>> Once the cat is alive + dead, he remains in that state for ever.
>>

>> THEN HOW COME WE NEVER OBSERVE THAT STATE? AG

>
> Because the observable are defined by their possible definite outcome,
> and for reason already explained, macroscopic superposition decoder,
> that is get entangled with the environment at a very high speed. So,
> if you look at the cat in the a+d state, you are duplicate almost
> immediately into a guy seeing the cat alive + the guy seeing the cat
> dead, and QM explained why they cannot interact, although they might
> interfere themselves.
>
> That is exactly a preferred basis -- which you seem to want to deny.
>
> Bruce
>
> In the case of a radioactive atom in state |decayed> + |undecayed>,
> what's the justification and advantage of the interpretation that it's
> in both states simultaneously? AG

This is what happens, as confirmed by experiment. In case the decay
happens fast and there is more than one decay channel, the decay will
happen to a superposition of the different possibilities. It's then not
a decay to one of the possibilities and we just don't know which one.
The difference between the two scenarios has in principle experimentally
verifiable consequences. For example, the Delta++ particle decays to a
proton and a positive pion due to the strong interaction. The strong
interaction obeys isospin symmetry. From this one can deduce by applying
a rotation in isospin space that the delta+ particle should decay to the
superposition sqrt(1/3)|n>|pi+> + sqrt(2/3)|p>|pi0> where |n> denotes a
neutron|p> a proton and |pi0> and |pi+> are neutral and positive pions.
Experiments have confirmed the relative decay probabilities of 1/3 and
2/3.

Saibal

[Alan Grayson]

But doesn't the either/or situation imply no interference? AG 

[Alan Grayson]

I don't see how this relates to my question. If the relative decay probabilites

are what you state, does this mean that the system PRIOR to decay is 

several different states simultaneously? AG 

[Philip Thrift]

In the case of radium atom decay or no-decay which kills or doesn't kill the cat, there is no interference of the two possible histories (as I understand what physically is going on). Only one history survives.

@philipthrift

[Alan Grayson]

Forget about the cat. For the radioactive source, can it ever be decayed and undecayed simultaneously, and if so, why? AG 

[Philip Thrift]

No.

It can "be" possibly-decayed and possibly-undecayed simultaneously.

That's as much as we can model the quantum nature of it.

@philipthrift

[smitra]

The system will in general be in a superposition, this follows from the
Schrodinger equation. The fact that a decay can happen at all means that
the particle states are not eigenstates of the full Hamiltonian. If you
consider a decay in a fixed volume and you impose reflecting boundary
conditions, then you won't get a permanent decay at all. The
superposition will end up oscillating back and forth from the original
particle to the decay products and back. When we compute the decay rate
in QM we need to take the limit to an infinite volume to eliminate this
oscillation effect and make the long term decay visible. But in
principle the superposition between the original undecayed particle and
the decay products will always continue to exist.

Saibal

[Alan Grayson]

I think that's the statistical interpretation of the wf. Doesn't that imply there is no interference? AG 

[Alan Grayson]

Thanks, but the issue I am raising is not whether a superposition continues to

exist, but the proper interpretation of it. For example, can a radioactive source

be decayed and undecayed simultaneously, or is Philip correct in claiming both

states are simultaneous possibilties? Huge difference. AG 

[Alan Grayson]

I think if one uses what I believe is the statistical interpretation of the wf, one is asserting that the wf tells us about our knowledge of the system, and nothing more; that is, the epistemological interpretation of the wf, not the ontological interpretation -- which leads to, say, the paradox of the radioactive source being IN two contradictory states simultaneously. OTOH, I seem to recall reading that the statistical (or epistemological)  interpretation has been generally rejected, possibly because it denies the existence of interference.  What's your assessment? TIA, AG

[Philip Thrift]

I has nothing to do with statistics, but with what is QM in terms of the probability (measure) space and the definition of probability (measure) for quantum phenomena.

The Concept of Probability in Quantum Mechanics

Richard P. Feynman

1951

http://www.johnboccio.com/research/quantum/notes/Feynman-Prob.pdf

Evolving Realities for Quantum Measure Theory

Henry Wilkes

September 28, 2018

https://arxiv.org/pdf/1809.10427.pdf

@philipthrift

[Alan Grayson]

Would you than say that the prevailing claim that the wf implies a radioactive source can be in two states simultaneously, decayed and undecayed, is an error due to an ontological interpretation, as distinquished from an epistemological interpretation of the wf? AG 

[Alan Grayson]

The statistical interpretation of QM asserts that the probabilities refer virtually solely to ensembles and not to individual  

[Alan Grayson]

The statistical interpretation of QM asserts that the probabilities refer virtually solely to ensembles of measurements of identically prepared systems and not to individual systems. Is this limitation the reason it is not generally accepted, as I believe is the case? Anyone can reply. AG

[Philip Thrift]

I suppose.

But this is more like the interpretation of probabilities as propensities.

https://en.wikipedia.org/wiki/Propensity_probability :

Propensities are not relative frequencies, but purported causes of the observed stable relative frequencies. 

In addition to explaining the emergence of stable relative frequencies, the idea of propensity is motivated by the desire to make sense of single-case probability attributions in quantum mechanics, such as the probability of decay of a particular atom at a particular time.

Sum over histories is also sum over possibilities - each possibility has a propensity.

@philipthrift 

[Alan Grayson]

The statistical interpretation could also fit the frequentist interpretation of probability. Truthfully, it's not clear what propensity means; sounds related to preferred bases, concerning which I have grave doubts. AG

[Philip Thrift]

Suppose you have the following product installed on your computer:

https://www.idquantique.com/wordpress/wp-content/uploads/Quantis-RNG-Products-500-x-400.png

Quantis Random Number Generator

https://www.idquantique.com/random-number-generation/products/quantis-random-number-generator/

Suppose you write a program that uses Quantis and it outputs

    01101   (with probability 1/32)

to the screen you are looking at.

Do you think:

A. There are 32 worlds that now exist and you-01101 are just in one of them, but there are 31 other you-s out there?

B. You-01101 is the one you that exists (in ine world), and all the possible you-s that are not you-01101 have vanished.

C. ?

@philipthrift 

[Bruno Marchal]

I have never denied a preferred basis, as preferred by the evolution of the type of observer we are (like molecular biological organism, where position plays an important role). What I deny is that the MWI implies that some base are more important in physics than other. The universal wave function can be described in any base, but the internal observer will “choose” the base corresponding to their most useful sensory apparatus. It is a bit like a planet and life: there are “preferred planet” having the right conditions for life to develop. Similarly, consciousness can only differentiate in the base in which Turing universal machine can also differentiate.

Bruno

Bruce

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[Bruno Marchal]

It seems to me that it is more like Popper’s propensity interpretation. But it makes not much sense. If the observer is described by the wave, and obey to Mechanism, he will not been able to see the difference between belonging to a possibility or an actuality, so Popper need a non computationalist theory of mind, which indeed he developed with Eccles, but it is hardly convincing, Imo.

Bruno

Doesn't that imply there is no interference? AG 

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[Bruno Marchal]

It implies that the possibilities, or the propensities, should be able to interfere, which is weird all by itself. The fact that it interfere and has physical consequences means that those possibilities are actual physical events, making dubious to call them “possibilities”. It looks like hiding a problem in a change of vocabulary.

Have you bought the little book by David Albert (Quantum Mechanics and Experience). Despite I disagree with his concise critics of Everett, and am unimpressed by its defence of de Broglie-Bohm hidden variable theory, I find it very pedagogical for its explanation of what the measurement problem consists in.

Bruno

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[Bruno Marchal]

That type of statistical interpretation was common, before it begun to be clear that we can obtain interference between a solitary particles and itself (as QM predicted). 

To give a rough summary, the choice is between consciousness reduce the wave (and thus mind acts on matter, and mind is not described by physics) or the observer obeys (quantum physics) in which case you get the MW (Everett).

Now,it is a theorem of Elementary Arithmetic (Peano) that “very elementary arithmetic” (Robison) are execute all computational histories, making physics into a first person plural statistics on histories, we can say that digital and quantum Mechanism corroborate each other quite well, as well as with the available facts.

The idea that consciousness reduces the Q-wave has been properly, imo, debunked by Abner Shimony.

Bruno

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[Bruno Marchal]

Just saying that the output is “01101” is ambiguous. If that comes from a mixed state, the 31 others do not exist. If it was coming from the tensor product of 5 superpositions (each one with a factor 1/sqrt(2)), then the 31 other “worlds/histories” are realised.

In that second case, you could have measure your output in another base, and distinguish if all bits are equal or not, for example, which means that the superposition were there. 

Bruno

B. You-01101 is the one you that exists (in ine world), and all the possible you-s that are not you-01101 have vanished.

C. ?

@philipthrift 

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[Brent Meeker]

On 11/14/2019 3:58 AM, Bruno Marchal wrote:

On 11 Nov 2019, at 12:35, Bruce Kellett <bhkel...@gmail.com> wrote:

On Mon, Nov 11, 2019 at 8:37 PM Bruno Marchal <mar...@ulb.ac.be> wrote:

On 10 Nov 2019, at 20:01, Alan Grayson <agrays...@gmail.com> wrote:

 

On Sunday, November 10, 2019 at 5:42:50 AM UTC-7, Bruno Marchal wrote:

Once the cat is alive + dead, he remains in that state for ever.

Then how come we NEVER observe that state? AG

Because the observable are defined by their possible definite outcome, and for reason already explained, macroscopic superposition decoder, that is get entangled with the environment at a very high speed. So, if you look at the cat in the a+d state, you are duplicate almost immediately into a guy seeing the cat alive + the guy seeing the cat dead, and QM explained why they cannot interact, although they might interfere themselves.

That is exactly a preferred basis -- which you seem to want to deny.

I have never denied a preferred basis, as preferred by the evolution of the type of observer we are (like molecular biological organism, where position plays an important role). What I deny is that the MWI implies that some base are more important in physics than other. The universal wave function can be described in any base, but the internal observer will “choose” the base corresponding to their most useful sensory apparatus.

That would imply that we could build instruments to detect states other than position, momentum, and others related to our senses.  We do that to a degree, but it is difficult and I don't think there is any chance that we could build a detector corresponding to an arbitrary projection operator.

Brent

It is a bit like a planet and life: there are “preferred planet” having the right conditions for life to develop. Similarly, consciousness can only differentiate in the base in which Turing universal machine can also differentiate.

Bruno

Bruce

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[Bruce Kellett]

On Thu, Nov 14, 2019 at 10:58 PM Bruno Marchal <mar...@ulb.ac.be> wrote:

On 11 Nov 2019, at 12:35, Bruce Kellett <bhkel...@gmail.com> wrote:

 

On Mon, Nov 11, 2019 at 8:37 PM Bruno Marchal <mar...@ulb.ac.be> wrote:

On 10 Nov 2019, at 20:01, Alan Grayson <agrays...@gmail.com> wrote:

 

On Sunday, November 10, 2019 at 5:42:50 AM UTC-7, Bruno Marchal wrote:

Once the cat is alive + dead, he remains in that state for ever.

Then how come we NEVER observe that state? AG

Because the observable are defined by their possible definite outcome, and for reason already explained, macroscopic superposition decoder, that is get entangled with the environment at a very high speed. So, if you look at the cat in the a+d state, you are duplicate almost immediately into a guy seeing the cat alive + the guy seeing the cat dead, and QM explained why they cannot interact, although they might interfere themselves.

That is exactly a preferred basis -- which you seem to want to deny.

I have never denied a preferred basis, as preferred by the evolution of the type of observer we are (like molecular biological organism, where position plays an important role).

As has been pointed out, evolution of observers plays no role in the existence of a preferred basis. The preferred basis arises from the normal physical interactions of quantum states with the environment. Observers play no role in this process. That is the message of Everett -- we must eliminate any mention of observers (or measurement) from our account of physics.

What I deny is that the MWI implies that some base are more important in physics than other.

That is where you are 100% wrong. The preferred basis, its existence and development, is central to physics. Sure, we can describe Hilbert space in any basis whatsoever, but we do not perceive Hilbert space -- the world we perceive definitely has a preferred basis.

The universal wave function can be described in any base, but the internal observer will “choose” the base corresponding to their most useful sensory apparatus.

No, again, it is not a matter of personal choice. The preferred basis is determined by the basic dynamics of the physical world, independently of any observer, or any observer's choice.

It is a bit like a planet and life: there are “preferred planet” having the right conditions for life to develop. Similarly, consciousness can only differentiate in the base in which Turing universal machine can also differentiate.

It is not at all like the fact that only certain planets have the right conditions for life. Life is irrelevant to the preferred basis. The important concept, as Zurek has stressed in his development of Quantum Darwinism, is the emergence of a classical world from the quantum substrate. Central to this, is the possibility of the formation, in the environment, of many copies of the information concerning the outcome of a quantum process. These many copies are central to the possibility of many observers coming to see the same result, and that leads to the emergence of an objective classical world. It is this objective classical world that is the basis of our experience, and it is that world that we are required to explain by our physics. Given that we have access only to a limited subset of the total information, we definitely have a mixed state -- this is the origin (in quantum Darwinism) of quantum jumps. Zurek's insight here is profound.

In order for the basis to be irrelevant, we would have to have access to all the copies of the information. If we have such access, then objectivity is lost -- others cannot access the information without disturbing the system. Consequently, independence of basis entails solipsism -- where only one individual would control all the information, and he can order this in any basis he likes. But that is not how things are in practice.

Bruce

[Alan Grayson]

OR, it could be that the Hilbert Space model of QM is flawed in implying that states can exist which can never be observed. AG 

[Alan Grayson]

I forget if I raised this issue here or on another thread. I am beginning to doubt that isolation is possible. When a particle is created, how can it be isolated from the environment? If it cannot be isolated, if it's never really isolated, the decoherence model fails to establish anything. AG 

[Brent Meeker]

On 11/17/2019 11:07 PM, Alan Grayson wrote:
>
> I forget if I raised this issue here or on another thread. I am
> beginning to doubt that isolation is possible. When a particle is
> created, how can it be isolated from the environment? If it cannot be
> isolated, if it's never really isolated, the decoherence model fails
> to establish anything. AG

Interactions are quantized like everything else.  There's smallest unit
of action, h.  So if the interaction is less than this it's zero.  So it
is possible to isolate variables.

Brent

[Alan Grayson]

But if, say, a particle is created by some process, won't it be entangled with the causal entities defining the process and therefore be initially, and forever, non-isolated? AG 

[Alan Grayson]

If that's too hot to handle, try this: if we write the standard superposition of a decayed or undecayed radioactive atom, is there any inherent problem with interpreting this superposition to mean it has a probability to be in one state or the other by applying Born's rule to each amplitude? Why did this interpretation apparently fall to the wayside, and was substituted for the baffling interpretation of the system being in both states simultaneously? AG 

[Alan Grayson]

It seems like a simple question aching for an answer. Why do physicists, many of them at least, prefer a baffling unintelligible interpretation of superposition, say in the case of a radioactive source, when the obvious non-contradictory one stares them in their collective faces? AG 

[Philip Thrift]

On Sunday, December 1, 2019 at 2:12:38 AM UTC-6, Alan Grayson wrote:

It seems like a simple question aching for an answer. Why do physicists, many of them at least, prefer a baffling unintelligible interpretation of superposition, say in the case of a radioactive source, when the obvious non-contradictory one stares them in their collective faces? AG 

The fundamental and psychological problem many physicists have is that they take some mathematics  (in some particular theory) and assign physical realities to its mathematical entities. Most of them do not understand the nature of mathematics: It's a language (or collection of languages) about mathematical entities - which are thought of differently depending on one's philosophy of mathematics. (It is best to say they are fictions.) This is especially true when probability theory (as defined in mathematics) is involved. This hopping between physical realities and mathematical entities leads them to them being unable to distinguish between them, or to communicate to the public the true nature of physics.

@philipthrift

[Alan Grayson]

Thanks for that! I'd like to hear Brent's and Bruce's opinion in this matter. AG 

[smitra]

The interpretation of a superposition as representing a system that can
be in one or the other state, is incompatible with interference
experiments. And physicist don't care much about interpretation and the
language used to communicate what certain concepts mean. So, many
physicists may say that a particle in a superposition between being in
position x and y is at x and y simultaneously, even though they know
that's not really what a superposition means (obviously there is only
one particle not 2). What matters is the mathematical formulation of the
theory, not the words used to describe this.
Saibal

[Philip Thrift]

Of course there is not "the mathematical formulation" (like the one approved catechism of an orthodox denomination), but there are multiple mathematical formulations that can match empirical data.

@philipthrift

[Bruno Marchal]

On 1 Dec 2019, at 09:51, Philip Thrift <cloud...@gmail.com> wrote:

On Sunday, December 1, 2019 at 2:12:38 AM UTC-6, Alan Grayson wrote:

It seems like a simple question aching for an answer. Why do physicists, many of them at least, prefer a baffling unintelligible interpretation of superposition, say in the case of a radioactive source, when the obvious non-contradictory one stares them in their collective faces? AG 

The fundamental and psychological problem many physicists have is that they take some mathematics  (in some particular theory) and assign physical realities to its mathematical entities.

That is the interesting problem. We use a mathematical formalism, but any simple relation between that formalism and reality, to be correct, needs to NOT make the superposed terms disappearing (indeed the quantum computation exploits typically different terms of the superposition, like already the two slits).

De Broglie defended the idea that quantum mechanics was false on distance bigger than an atom, and predicted that the EPR influence is absent on any macroscopic distance, advocating your idea that the formalism should not be taken literally; but eventually Bell has shown this to be testable, and Nature has confirmed the formalism (Aspect and followers).

So, it is just false to NOT attribute a physical reality to all terms in the wave. We would lost the interference effect. The problem of how to interpret the wave is not solved by distantiation with the wave formalism, as Nature confirms the weirdness imposed to the formalism. 

Most of them do not understand the nature of mathematics: It's a language (or collection of languages) about mathematical entities - which are thought of differently depending on one's philosophy of mathematics. (It is best to say they are fictions.) This is especially true when probability theory (as defined in mathematics) is involved.

With QM, the problem is that the amplitude of probability do interfere. In arithmetic too, and for a mechanist, the conceptual problems are solved in a radical way, as there is no time, nor space, only correlated minds. The fiction is not in the math, but in the assumption that “physical” means ontological.

This hopping between physical realities and mathematical entities leads them to them being unable to distinguish between them, or to communicate to the public the true nature of physics.

I would say that the problem comes from the materialists who mostly seem unable to understand that the assumption of an ontological physical universe is a very BIG assumption, without any evidences to sustain it, beyond the natural instinctive extrapolation from simple experiences. When doing metaphysics with the scientific method, it is important to be agnostic on this, as it is the very subject of the research. 

Bruno

@philipthrift

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[Philip Thrift]

On Monday, December 2, 2019 at 3:26:44 AM UTC-6, Bruno Marchal wrote:

On 1 Dec 2019, at 09:51, Philip Thrift <cloud...@gmail.com> wrote:

On Sunday, December 1, 2019 at 2:12:38 AM UTC-6, Alan Grayson wrote:

It seems like a simple question aching for an answer. Why do physicists, many of them at least, prefer a baffling unintelligible interpretation of superposition, say in the case of a radioactive source, when the obvious non-contradictory one stares them in their collective faces? AG 

The fundamental and psychological problem many physicists have is that they take some mathematics  (in some particular theory) and assign physical realities to its mathematical entities.

That is the interesting problem. We use a mathematical formalism, but any simple relation between that formalism and reality, to be correct, needs to NOT make the superposed terms disappearing (indeed the quantum computation exploits typically different terms of the superposition, like already the two slits).

De Broglie defended the idea that quantum mechanics was false on distance bigger than an atom, and predicted that the EPR influence is absent on any macroscopic distance, advocating your idea that the formalism should not be taken literally; but eventually Bell has shown this to be testable, and Nature has confirmed the formalism (Aspect and followers).

So, it is just false to NOT attribute a physical reality to all terms in the wave. We would lost the interference effect. The problem of how to interpret the wave is not solved by distantiation with the wave formalism, as Nature confirms the weirdness imposed to the formalism. 

Most of them do not understand the nature of mathematics: It's a language (or collection of languages) about mathematical entities - which are thought of differently depending on one's philosophy of mathematics. (It is best to say they are fictions.) This is especially true when probability theory (as defined in mathematics) is involved.

With QM, the problem is that the amplitude of probability do interfere. In arithmetic too, and for a mechanist, the conceptual problems are solved in a radical way, as there is no time, nor space, only correlated minds. The fiction is not in the math, but in the assumption that “physical” means ontological.

This hopping between physical realities and mathematical entities leads them to them being unable to distinguish between them, or to communicate to the public the true nature of physics.

I would say that the problem comes from the materialists who mostly seem unable to understand that the assumption of an ontological physical universe is a very BIG assumption, without any evidences to sustain it, beyond the natural instinctive extrapolation from simple experiences. When doing metaphysics with the scientific method, it is important to be agnostic on this, as it is the very subject of the research. 

Bruno

"So, it is just false to NOT attribute a physical reality to all terms in the wave."

There are formulations without the wave function, so - until there is more that can be found out about what's "below" the quantum phenomena we've observed so far - the wave function can be done without.

All these formulations (with or without wave functions) give the same probabilities to match to experiments, but "Counterfactual indefiniteness" remains

@philipthrift

[Alan Grayson]

Please provide more detail to support this claim. TIA, AG

 

And physicist don't care much about interpretation and the
language used to communicate what certain concepts mean. So, many
physicists may say that a particle in a superposition between being in
position x and y is at x and y simultaneously, even though they know
that's not really what a superposition means (obviously there is only
one particle not 2). What matters is the mathematical formulation of the
theory, not the words used to describe this.
Saibal

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[Bruno Marchal]

What I said did not depend on the formulation of quantum mechanics. All formulations are equivalent (in the non relativist case; in the relativist case Feynman’s formulation (generalising Dirac) is the correct one.

All these formulations (with or without wave functions) give the same probabilities to match to experiments, but "Counterfactual indefiniteness” remains

In all formulations of QM, and also just with Mechanism, we have a similar problem.

With Mechanism, or with Everett’s formulation, the indefiniteness of the counterfactual admits a simple non magical explanation (as I try sometimes to explain intuitively with the thought experiences). The counterfactual indefiniteness becomes a particular case of the indefiniteness of whatever your “mental accessible neighbourhood” does not depend on. All personal lives are given by sequences of projections on the partial trace of a universal dovetailer, and this can be tested by comparing the logic of the quantum alternatives with the logic of the classical alternative seen by some “right” self-referential modes. There is the room there, as we get variate quantum logics for all first person singular and plural modes of self-references.

I recall that all modes of self-reference are given by the variant of the definition of knowledge by Theaetetus, which are imposed by incompleteness (cf p, []p, []p & p, []p & <>t, []p & <>t & p). No self-referentially correct universal machine “believing in the induction axioms” (which makes it Gödel-Löbian) can miss this.

Digital Mechanism includes the Church-Turing thesis, which makes us able to translate many problem in the “philosophy of mind” of the universal machine into mathematical problem. The main discoveries is that the machines universal believing in enough induction axioms, like PA (Peano Arithmetic), is aware of its own limitation, and very simple inductive inference abilities makes such machine quickly aware of the “mind-body problem”. You can define (reflexive) consciousness by the “knowledge” of your ignorance, and such machine will come up with terms for those things they cannot defined without referring to some implicit or explicit “absolute truth”. With Mechanism, the sigma_1 truth is enough, but of course, to prove this you need much more (I expect pi_1 in the oracle of Truth, that is bigger (in unsolvability degrees) than all the sigma_i and pi_i.

The arithmetical reality explains itself, including the stable physical histories, and the existence of a non rationally justifiable part of what it is nevertheless able to know.

Mechanism does not allow the axiom if the infinite, but this does not mean that the machine believing in the infinite, like believing in the complex numbers, will not be better than those who don’t, notably those questions related only to numbers and digital machines.

The analytical, the topological, the physical, … are internal arithmetical views, , which result from infinitely many projections from the space of histories to history. Technically, the invariance of the first person experience for the arithmetical “delays” of reconstitution plays a role to “stabilise” the sharable histories, and some dovetailing on random numbers too. We are multiplied by large infinities.

You did mention linear logic, which is indeed a good tool to get the tensorial many-bodies structure, but that linearity has to be extracted from the modes of self-reference if we want to keep track of the justifiable and non justifiable part of the first person knowledge. The thought experience provides a tensor by the sharing of multiple observer of the annihilation and reconstitution boxes, but in arithmetic we get too many tensor products, and it is hard to make it unique from the self-reference. It should, but the nesting of the modalities makes it intractable. As suggested by what it describes, we might need a quantum computer!

Somehow, the physical reality is the derivative of the mind of the universal machine, or the mind of the universal machine is the sum of the physical histories accessible by the universal machine, but that is true only in the limit, in a sense related to Solovay G*.

Bruno

@philipthrift

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[Alan Grayson]

The interpretation of a superposition as representing a system that can
be in one or the other state, is incompatible with interference
experiments.

*Please, if you can, elaborate why this is the case? AG*

And physicist don't care much about interpretation and the
language used to communicate what certain concepts mean. So, many
physicists may say that a particle in a superposition between being in
position x and y is at x and y simultaneously, even though they know
that's not really what a superposition means (obviously there is only
one particle not 2). What matters is the mathematical formulation of the
theory, not the words used to describe this.
Saibal

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