Re: Consistency of Postulates of QM

[agrayson2000]

On Wednesday, December 13, 2017 at 10:44:14 PM UTC, Brent wrote:
>
>
>
> On 12/13/2017 2:20 PM, agrays...@gmail.com  wrote:
>
>
>
> On Wednesday, December 13, 2017 at 9:15:36 PM UTC, Brent wrote: 
>>
>>
>>
>> On 12/13/2017 2:45 AM, agrays...@gmail.com wrote:
>>
>> * BUT for a nucleus of a radioactive element, the nucleus is never 
>> Decayed and Undecayed SIMULTANEOUSLY.*
>>
>> Sure it is.  It's in a coherent superposition of those states until it 
>> interacts with the environment.
>>
>> Brent
>>
>
> * That's the conventional QM wisdom and the cause of the paradox of a cat 
> Alive and Dead simultaneously. As I explained, the fallacy is rooted in an 
> unjustified generalization of the double slit experiment where the 
> probability waves do, in fact, exist simultaneously.  What waves do you 
> claim are interacting for the radioactive nucleus to produce coherence? 
> Tell me about them. I am from Missouri. AG*
>
>
> You seem to think that coherence requires two different waves.  This is 
> the wrong way to look at it.  In Young's slits experiment there is only one 
> wave, which goes through both slits and interferes with itself.  And 
> unstable nucleus has a probability amplitude that includes a "decayed" part 
> and a "not decayed" part.  It's a tunneling problem.
>
> Brent
>

*See,  https://en.wikipedia.org/wiki/Coherence_(physics*)

*How can you have coherence with a single wave? What does it mean? How 
would you define it? AG*

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Re: Schrodinger's cat problem; proposed solution

[agrayson2000]

On Friday, December 15, 2017 at 5:20:34 AM UTC, Brent wrote:
>
>
>
> On 12/14/2017 6:27 PM, Jason Resch wrote:
>
>
>> *I don't see how Wigner's friend presents a problem for Copenhagen. 
>> According to the CI, the wf collapses when the system measured, which is 
>> when the box is opened. What am I missing? The issue of the cat's memory is 
>> a different matter, problematic IMO. AG *
>>  
>>
>
> The problem is according to the CI, an isolated system evolves according 
> to the Shrodinger equation, and therefore does not collapse.  But it also 
> says observation causes collapse. 
>
>
> That is not CI.  CI always supposed there is a classical realm in which 
> measurements and observations were made by classical devices.  Wigner toyed 
> with the idea that consciousness was required, but that was never Bohr's 
> idea of CI.  In a sense, decoherence filled in CI by providing the 
> mechanism of collapse.
>
> Brent
>

*Jason's comment and yours are not necessarily in contradiction. How did 
decoherence provide the mechanism for collapse? Isn't it more a hope than a 
reality? AG *

>
> So when you have a conscious observer who is himself part of an isolated 
> system, from the point of view of another conscious observer, which rule 
> wins?
>
>
>

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Re: Schrodinger's cat problem; proposed solution

[Brent Meeker]

On 12/14/2017 6:27 PM, Jason Resch wrote:


*I don't see how Wigner's friend presents a problem for
Copenhagen. According to the CI, the wf collapses when the system
measured, which is when the box is opened. What am I missing? The
issue of the cat's memory is a different matter, problematic IMO. AG
*


The problem is according to the CI, an isolated system evolves 
according to the Shrodinger equation, and therefore does not 
collapse.  But it also says observation causes collapse.


That is not CI.  CI always supposed there is a classical realm in which 
measurements and observations were made by classical devices. Wigner 
toyed with the idea that consciousness was required, but that was never 
Bohr's idea of CI.  In a sense, decoherence filled in CI by providing 
the mechanism of collapse.


Brent

So when you have a conscious observer who is himself part of an 
isolated system, from the point of view of another conscious observer, 
which rule wins?


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Re: Schrodinger's cat problem; proposed solution

[agrayson2000]

On Friday, December 15, 2017 at 2:27:46 AM UTC, Jason wrote:
>
>
>
> On Thu, Dec 14, 2017 at 8:20 PM,  
> wrote:
>
>>
>>
>> On Thursday, December 14, 2017 at 2:54:01 PM UTC, Jason wrote:
>>>
>>> The solution was proposed by Everett in 1957, collapse is a subjective 
>>> illusion.  The dead cat and its history of decomposing for the previous 
>>> hour does not materialize out of nothing from the mere act of looking at it.
>>>
>>>
>>> No measurement is made of the cat, the Geiger counter, or the atom, by 
>>> anyone outside the isolated system of the box, so according to the 
>>> Copenhagen Interpretation the superposition does not collapse. The cat is 
>>> both alive and dead. That is, until someone opens the door to peek inside. 
>>> In that instant, the wave function collapses and the system randomly 
>>> “decides” whether the cat is alive or dead. 
>>>
>>>  
>>
>>> If the state collapses to that of the dead cat, what happens to the 
>>> experiences of the cat who was in the superposition of being alive and dead 
>>> over the past hour? Do they suddenly vanish as if they never happened at 
>>> all? Perhaps they never existed in the first place, as Bohr’s anti-realist 
>>> approach would answer. But this leads to another problem: if the cat is 
>>> observed to be alive, do all of its memories and experiences over the 
>>> past hour suddenly pop into existence? Is the cat’s experience of 15 
>>> minutes ago ever experienced? 
>>>
>>>  
>>
>>> It is one thing to believe that microscopic particles might be in two 
>>> different states at once, but quite another to believe the same for a large 
>>> and complex system, such as a cat. The CI implies that a living, breathing 
>>> cat, with a consistent history and memories of the previous hour, can 
>>> instantly materialize from the simple act of observation.
>>>
>>>  
>>
>>> Schrödinger's experiment has also been extended to highlight other 
>>> problems. The mathematical physicist Eugene Wigner discussed a thought 
>>> experiment known as Wigner’s friend. In it, Wigner’s friend is in a room 
>>> that is sealed off from the rest of the world and in that room is a box 
>>> containing Schrödinger's cat. The friend opens the box after an hour and 
>>> notices whether or not the cat is alive. Sometime later, Wigner opens the 
>>> door to the room to check on his friend. When does the wave function 
>>> collapse, when the friend checks on the cat, or when Wigner checks on 
>>> his friend? If it is when the friend checks on the cat, then the isolated 
>>> system, unobserved by Wigner, has already collapsed (in contradiction to 
>>> the CI). Yet, if it does not collapse for the friend checking on the cat, 
>>> this is another contradiction, for he has made an observation of a system 
>>> in a superposition. The CI seems to have difficulties handling multiple 
>>> observers. mea
>>>
>>>
>>
>> *I don't see how Wigner's friend presents a problem for Copenhagen. 
>> According to the CI, the wf collapses when the system measured, which is 
>> when the box is opened. What am I missing? The issue of the cat's memory is 
>> a different matter, problematic IMO. AG *
>>  
>>
>
> The problem is according to the CI, an isolated system evolves according 
> to the Shrodinger equation, and therefore does not collapse.  But it also 
> says observation causes collapse. So when you have a conscious observer who 
> is himself part of an isolated system, from the point of view of another 
> conscious observer, which rule wins?
>

*If the system isn't isolated, it cannot be in a superposition of states. 
So including the observer as part of the system is self defeating if one 
wants to do a quantum experiment. The existence of an observer doesn't 
contradict isolation of the system if the observer is an instrument 
recording the result. AG *

>
> Jason
>  
>
>> If one takes the stance that the first conscious entity to experience the 
>>> result of a measurement causes collapse, whether isolated or not, this 
>>> still leaves the problem of large macroscopic systems with complex 
>>> histories popping into existence through observation. If we replace the cat 
>>> with some unconscious device, like a sensor that prints off a receipt with 
>>> the result of whether or not the poison was released, then a conscious 
>>> observer opening the box causes the instantaneous appearance of the print 
>>> out, oddly, with ink that has long-since dried. It has a consistent history 
>>> seemingly invented at once. 
>>>
>>> Einstein was most impressed with Schrödinger's paper, and in 1950 wrote 
>>> Schrödinger a letter of praise, saying “You are the only contemporary 
>>> physicist, besides Laue, who sees that one cannot get around the 
>>> assumption of reality, if only one is honest. Most of them simply do not 
>>> see what sort of risky game they are playing with reality—reality as 
>>> something independent of what is experimentally established. Their 
>>> 

Re: Schrodinger's cat problem; proposed solution

[Jason Resch]

On Thu, Dec 14, 2017 at 8:20 PM,  wrote:

>
>
> On Thursday, December 14, 2017 at 2:54:01 PM UTC, Jason wrote:
>>
>> The solution was proposed by Everett in 1957, collapse is a subjective
>> illusion.  The dead cat and its history of decomposing for the previous
>> hour does not materialize out of nothing from the mere act of looking at it.
>>
>>
>> No measurement is made of the cat, the Geiger counter, or the atom, by
>> anyone outside the isolated system of the box, so according to the
>> Copenhagen Interpretation the superposition does not collapse. The cat is
>> both alive and dead. That is, until someone opens the door to peek inside.
>> In that instant, the wave function collapses and the system randomly
>> “decides” whether the cat is alive or dead.
>>
>>
>
>> If the state collapses to that of the dead cat, what happens to the
>> experiences of the cat who was in the superposition of being alive and dead
>> over the past hour? Do they suddenly vanish as if they never happened at
>> all? Perhaps they never existed in the first place, as Bohr’s anti-realist
>> approach would answer. But this leads to another problem: if the cat is
>> observed to be alive, do all of its memories and experiences over the
>> past hour suddenly pop into existence? Is the cat’s experience of 15
>> minutes ago ever experienced?
>>
>>
>
>> It is one thing to believe that microscopic particles might be in two
>> different states at once, but quite another to believe the same for a large
>> and complex system, such as a cat. The CI implies that a living, breathing
>> cat, with a consistent history and memories of the previous hour, can
>> instantly materialize from the simple act of observation.
>>
>>
>
>> Schrödinger's experiment has also been extended to highlight other
>> problems. The mathematical physicist Eugene Wigner discussed a thought
>> experiment known as Wigner’s friend. In it, Wigner’s friend is in a room
>> that is sealed off from the rest of the world and in that room is a box
>> containing Schrödinger's cat. The friend opens the box after an hour and
>> notices whether or not the cat is alive. Sometime later, Wigner opens the
>> door to the room to check on his friend. When does the wave function
>> collapse, when the friend checks on the cat, or when Wigner checks on
>> his friend? If it is when the friend checks on the cat, then the isolated
>> system, unobserved by Wigner, has already collapsed (in contradiction to
>> the CI). Yet, if it does not collapse for the friend checking on the cat,
>> this is another contradiction, for he has made an observation of a system
>> in a superposition. The CI seems to have difficulties handling multiple
>> observers. mea
>>
>>
>
> *I don't see how Wigner's friend presents a problem for Copenhagen.
> According to the CI, the wf collapses when the system measured, which is
> when the box is opened. What am I missing? The issue of the cat's memory is
> a different matter, problematic IMO. AG *
>
>

The problem is according to the CI, an isolated system evolves according to
the Shrodinger equation, and therefore does not collapse.  But it also says
observation causes collapse. So when you have a conscious observer who is
himself part of an isolated system, from the point of view of another
conscious observer, which rule wins?

Jason


> If one takes the stance that the first conscious entity to experience the
>> result of a measurement causes collapse, whether isolated or not, this
>> still leaves the problem of large macroscopic systems with complex
>> histories popping into existence through observation. If we replace the cat
>> with some unconscious device, like a sensor that prints off a receipt with
>> the result of whether or not the poison was released, then a conscious
>> observer opening the box causes the instantaneous appearance of the print
>> out, oddly, with ink that has long-since dried. It has a consistent history
>> seemingly invented at once.
>>
>> Einstein was most impressed with Schrödinger's paper, and in 1950 wrote
>> Schrödinger a letter of praise, saying “You are the only contemporary
>> physicist, besides Laue, who sees that one cannot get around the
>> assumption of reality, if only one is honest. Most of them simply do not
>> see what sort of risky game they are playing with reality—reality as
>> something independent of what is experimentally established. Their
>> interpretation is, however, refuted most elegantly by your system of
>> radioactive atom + amplifier + charge of gunpowder + cat in a box, in which
>> the psi- function of the system contains both the cat alive and blown to
>> bits. Nobody really doubts that the presence or absence of the cat is
>> something independent of the act of observation.”
>>
>> Einstein never accepted the quantum mechanics as a complete theory. To
>> the end of his life he searched for a theory that better fit his ideals of
>> realism, causality and determinism. But the answer he 

Re: Schrodinger's cat problem; proposed solution

[agrayson2000]

On Thursday, December 14, 2017 at 2:54:01 PM UTC, Jason wrote:
>
> The solution was proposed by Everett in 1957, collapse is a subjective 
> illusion.  The dead cat and its history of decomposing for the previous 
> hour does not materialize out of nothing from the mere act of looking at it.
>
>
> No measurement is made of the cat, the Geiger counter, or the atom, by 
> anyone outside the isolated system of the box, so according to the 
> Copenhagen Interpretation the superposition does not collapse. The cat is 
> both alive and dead. That is, until someone opens the door to peek inside. 
> In that instant, the wave function collapses and the system randomly 
> “decides” whether the cat is alive or dead. 
>
>  

> If the state collapses to that of the dead cat, what happens to the 
> experiences of the cat who was in the superposition of being alive and dead 
> over the past hour? Do they suddenly vanish as if they never happened at 
> all? Perhaps they never existed in the first place, as Bohr’s anti-realist 
> approach would answer. But this leads to another problem: if the cat is 
> observed to be alive, do all of its memories and experiences over the 
> past hour suddenly pop into existence? Is the cat’s experience of 15 
> minutes ago ever experienced? 
>
>  

> It is one thing to believe that microscopic particles might be in two 
> different states at once, but quite another to believe the same for a large 
> and complex system, such as a cat. The CI implies that a living, breathing 
> cat, with a consistent history and memories of the previous hour, can 
> instantly materialize from the simple act of observation.
>
>  

> Schrödinger's experiment has also been extended to highlight other 
> problems. The mathematical physicist Eugene Wigner discussed a thought 
> experiment known as Wigner’s friend. In it, Wigner’s friend is in a room 
> that is sealed off from the rest of the world and in that room is a box 
> containing Schrödinger's cat. The friend opens the box after an hour and 
> notices whether or not the cat is alive. Sometime later, Wigner opens the 
> door to the room to check on his friend. When does the wave function 
> collapse, when the friend checks on the cat, or when Wigner checks on his 
> friend? If it is when the friend checks on the cat, then the isolated 
> system, unobserved by Wigner, has already collapsed (in contradiction to 
> the CI). Yet, if it does not collapse for the friend checking on the cat, 
> this is another contradiction, for he has made an observation of a system 
> in a superposition. The CI seems to have difficulties handling multiple 
> observers. mea
>
>

*I don't see how Wigner's friend presents a problem for Copenhagen. 
According to the CI, the wf collapses when the system measured, which is 
when the box is opened. What am I missing? The issue of the cat's memory is 
a different matter, problematic IMO. AG *
 

> If one takes the stance that the first conscious entity to experience the 
> result of a measurement causes collapse, whether isolated or not, this 
> still leaves the problem of large macroscopic systems with complex 
> histories popping into existence through observation. If we replace the cat 
> with some unconscious device, like a sensor that prints off a receipt with 
> the result of whether or not the poison was released, then a conscious 
> observer opening the box causes the instantaneous appearance of the print 
> out, oddly, with ink that has long-since dried. It has a consistent history 
> seemingly invented at once. 
>
> Einstein was most impressed with Schrödinger's paper, and in 1950 wrote 
> Schrödinger a letter of praise, saying “You are the only contemporary 
> physicist, besides Laue, who sees that one cannot get around the 
> assumption of reality, if only one is honest. Most of them simply do not 
> see what sort of risky game they are playing with reality—reality as 
> something independent of what is experimentally established. Their 
> interpretation is, however, refuted most elegantly by your system of 
> radioactive atom + amplifier + charge of gunpowder + cat in a box, in which 
> the psi- function of the system contains both the cat alive and blown to 
> bits. Nobody really doubts that the presence or absence of the cat is 
> something independent of the act of observation.” 
>
> Einstein never accepted the quantum mechanics as a complete theory. To the 
> end of his life he searched for a theory that better fit his ideals of 
> realism, causality and determinism. But the answer he sought was there all 
> along: in the equations of quantum mechanics. Consciously or unconsciously, 
> however, the answer was simply too strange for anyone to consider, even for 
> a moment. It was not until 1957, more than three decades after quantum 
> mechanics was formulated, that anyone was bold enough to point out the 
> answer that was staring everyone in the face. That person was Hugh Everett 
> III. 
>
>
> Jason
>
> On 

Re: Consistency of Postulates of QM

[agrayson2000]

On Wednesday, December 13, 2017 at 10:45:40 AM UTC, agrays...@gmail.com 
wrote:
>
>
>
> On Wednesday, December 13, 2017 at 7:41:00 AM UTC, agrays...@gmail.com 
> wrote:
>>
>>
>>
>> On Wednesday, December 13, 2017 at 5:55:59 AM UTC, Bruce wrote:
>>>
>>> On 13/12/2017 11:41 am, agrays...@gmail.com wrote:
>>>
>>> On Tuesday, December 12, 2017 at 10:52:12 PM UTC, Bruce wrote: 

 On 13/12/2017 9:45 am, agrays...@gmail.com wrote:

 On Tuesday, December 12, 2017 at 10:14:01 PM UTC, Bruce wrote: 
>
>
> So Schrödinger's cat was once a coherent state of a cat in a box, and 
> the splitting occurs with the decay of a nucleus; 


 *Unlike the double slit experiment, which can only be understood with 
 interference and the model that the electron wave, say, goes through both 
 slits, the nuclear decay is a BINARY event, very roughly like a coin toss 
 where there is no interference. Generalizing interference to every quantum 
 state is where Schrodinger went wrong. The cat, which shares or inherits 
 the wf from the radioactive decay, is never in both Alive and Dead states 
 simultaneously. AG*


 In the double slit, the paths through the two slits remain coherent, so 
 they can interfere when they come together. In the case of nuclear decay, 
 the coherence is lost immediately, so the nucleus does not interfere with 
 the decay products.

 Bruce

>>>
>>> *So you agree or disagree with my conclusion; namely, the cat is never 
>>> in a superposition of states? That is, no situation where cat is Alive and 
>>> Dead simultaneously. I think you disagree and think the nuclear state is 
>>> superposed with interference existing. AG*
>>>
>>>
>>> The superposition of |live + dead> or |live - dead> does not exist in 
>>> any single world since such states are not stable against decoherence. But 
>>> if you take the pedantic view of the many worlds of MWI, the superposition 
>>> of live and dead cats, together with everything entangled with them, exists 
>>> for ever in the multiverse. What good that does anyone, I fail to 
>>> understand.
>>>
>>> Bruce
>>>
>>
>> *I am not referring to the MWI. I am referring to whether in 
>> Schrodinger's cat experiment, the wf of the radioactive source, ( |decayed> 
>> + |undecayed> ) , is a superposition of states without interference between 
>> its components. If that's the case, perhaps what you would call an 
>> "incoherent superposition", then the cat which shares or inherits this wf 
>> in Schrodinger's set up, is never in a state of Alive and Dead 
>> simultaneously. AG*
>>
>> *You can look at it this way; in the double slit experiment, the 
>> probability wave of the electron, say, passes through both slits 
>> SIMULTANEOUSLY. As a result, it is conceptually feasible to model 
>> interference between the waves, giving rise to the correct distribution on 
>> the screen. This is the seminal experiment in QM and gives rise to the 
>> general interpretation that a system in a superposition can be in multiple 
>> states simultaneously. BUT for a nucleus of a radioactive element, the 
>> nucleus is never Decayed and Undecayed SIMULTANEOUSLY. Thus, it makes no 
>> sense to believe there can be interference between the states. Absent 
>> interference means the cat tied to the radioactive source can never be in 
>> the Alive and Dead states SIMULTANEOUSLY. AG*
>>
>
And the answer is (drum roll please); SHUT UP AND CALCULATE! AG

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Re: Consistency of Postulates of QM

[Bruce Kellett]

On 15/12/2017 10:15 am, smitra wrote:

On 14-12-2017 22:35, Bruce Kellett wrote:


 I think this argument pre-dates the work by Zeh and Zurek developing
the idea of decoherence. Decoherence remove the oddities of Copenhagen
as presented above in that it is not consciousness that does the work,
but decoherence. Bohr was saying essentially the same thing (though he
didn't know the words) when he talked about the importance of the
whole experimental set up.

 That aside, Deutsch's idea fails because he has not fully implemented
quantum erasure. If a record exists of the fact that a 'welcher weg'
measurement was made, entanglement of the rest of the world with the
result of that measurement is not erased by merely resetting the
memory of the mind or computer. So in the proposed experiment, the
interference pattern is absent, and it is not a proper 'delayed
choice' situation.

Deutsch has also given a rigorous variant of this that I summarized in 
my paper. It is possible in theory to experimentally prove the 
existence of other branches where a different measurement result was 
obtained. It's only impossible FAPP.


From your paper, summarizing Deutsch:
"Suppose an observer measures the z-component of a spin that is 
polarized in the x-direction. Then there exits a unitary operator that 
disentangles the observer from the spin, causing the observer to forget 
the result of the measurement. However, he would still remember having 
measured the z-component of the spin. In the MWI, the spin will be in 
its original state and therefore measuring the x-component will yield 
spin up with 100% probability. In any collapse interpretation, measuring 
the x-component will yield spin up or spin down with 50% probability."


This is equivalent to the argument John reported, and your reference 
dates from 1985. That is before decoherence theory and entanglement with 
the environment was fully understood, and predates the significant 
quantum erasure experiments. For that reason, Deutsch has got it 
seriously wrong, because the unitary operation he envisages does not 
exist, even in principle, and he has not fully implemented quantum erasure.


His scenario can be approximated in quantum erasure experiments, and 
because the erasure is not complete, the results obtained will be 
identical to those predicted by a collapse model. In order to use time 
reversal invariance to recover the initial state in MWI, you have to 
reverse absolutely everything, so you cannot leave a record in the 
environment that some measurement was made -- such a record means that 
there has not been compete reversal, so the original state is not recovered.


Bruce

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Re: Consistency of Postulates of QM

[Bruce Kellett]

On 15/12/2017 10:08 am, smitra wrote:

On 14-12-2017 22:39, Bruce Kellett wrote:


The thing about mixed states is that they are inevitable if you write
the state of a system as a tensor product of the separate states of
subsystems. The separate subsystems are not pure states because of
entanglement between them.

There is entanglement with the environment but the same computational 
state appears in different "decoherent" branches.


This is conjecture only -- has not been demonstrated.

You don't per se need to invoke any mixed states. Also, it's a well 
known fact that any mixed state can be considered to be a pure state 
of a larger system, the so-called "purification" of the state.


Maybe, but then your calculation doesn't go through.

But all this is rather beside the point. We can talk about your paper 
separately if you wish, but the main point is that you still have not 
risen to the challenge I offered: start from the decohered state |coin> 
and derive the state {|heads > + |tails>} by purely unitary interactions 
with the environment -- such as by shaking etc (Not by a contrived 
entanglement with some single quantum process such as a nuclear decay.)


Bruce

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Re: Consistency of Postulates of QM

[smitra]

On 15-12-2017 00:08, smitra wrote:

On 14-12-2017 22:39, Bruce Kellett wrote:

On 14/12/2017 11:20 pm, smitra wrote:

On 14-12-2017 12:43, Bruce Kellett wrote:

On 14/12/2017 9:23 pm, smitra wrote:

On 14-12-2017 02:35, Bruce Kellett wrote:

On 14/12/2017 11:52 am, smitra wrote:

On 13-12-2017 22:55, Bruce Kellett wrote:

On 14/12/2017 8:23 am, smitra wrote:


So, let's examine this more closely. We start with a state that 
is a superposition of branches that each undergo classical 
evolution, so I'm not now appealing to the arguments in the 
paper by Albrecht. Then we end up with a state of the form:


 Sum over j [|heads(j)>|env(heads,j)> +

 Sum over j |tails(j)>|env(tails,j)>]

where j enumerates microstates of the coin and the state of the 
environment in each sector where the coin is heads or tails 
depends on the microstate of the coin. The coin states are not 
normalized, the norms are chosen to yield the correct 
probabilities.  E.g. if tails has zero probability then all the 
|tail(j)> are given a norm of zero. So, the above expression is 
completely general.


Now, I'm part of the environment, so we can write:

|env(X,j)> = Sum over k of |me(X,Y,j,k)>|env'(X,Y,j,k)>

where X is heads or tails, Y, denotes my macrostate that I'll 
define below, j denotes the microstate of the coin and k sums 
over microstates corresponding to macrostate Y.


This splitting of my state into a macrostate Y and microstate k 
is in principle arbitrary, we can choose this splitting such 
that Y keep tracts of what I'm aware of and then k takes into 
account all the other degrees of freedom in my body and brain 
that I'm not aware of. E.g. if I were a digital computer then Y 
would correspond to some bitstring defined by the computational 
state of the computer and we then sum over all the possible 
microstates that correspond to some fixed macrostate.


Then when I'm not yet aware of the result of the coin throw, we 
have:


|me(X,Y,j,k)> = |Awareness(Y)>|body(X,Y,j,k)>

where Y contains all the information that I am aware of, and 
that doesn't include the result if the coin throw nor 
information contained only at the microscopic scale. So, 
Awareness (Y) for a given Y defines who I am, where I am , and 
what I'm experiencing.


It should be clear that despite decoherence, |Awareness(Y)> 
will factor out of the global superposition as it doesn't 
depend on X, k and j.


So, given what I know, I cannot tell in which branch I am. 
Therefore unless all the branches corresponding to one outcome 
have zero norm,  I will have copies in both branches.


There is just no way that all the information describing what 
I'm aware of at some moment is going to constrain how someone 
else can throw a coin to such a degree that the outcome will be 
fixed.


So the end point of your analysis is that you can't see how it 
could
be possible that you are not right? The outcome is fixed -- and 
the

same -- in all worlds in which you participate!

But it is quite easy to see what is going on. Since it is all
independent of your awareness, we can factor that out of the
summations. And you still do not get a coherent superposition 
from a

decoherent mixture. What goes on in the world is independent of
whether or not the rock on the floor is aware of it or not. You 
are
not in a position any different from that of said rock. Look at 
the

expansion for Schrödinger's cat:

  |nucleus>|box>|cat>you>|environment> -->

 {|decayed>|poison spilt>|cat dead>|You>|environment records 
dead cat>
 + |undecayed>|poison intact>|cat alive>|You>|environment 
records live cat>}


You can see that your state does not change (is irrelevant) 
until you
interact with the environment in such a way that your 
consciousness
becomes entangled with the state of the cat. This is not 
mysterious,

and it is not changed just because you claim there is some magic
associated with consciousness that makes a difference. You are 
just
reverting to Copenhagen or many minds where consciousness is 
necessary

for the understanding of QM.



The lack of coherence is not relevant unless it affects the two 
states denoted by |you>.


That is not true.

If you have a coherent superposition then it's clear that the two 
|you>'s are identical.


No, it is not. In the above expansion of the cat scenario, I have 
a
coherent superposition of live and dead cats -- in different 
branches

of course, but until decoherence separates the worlds, the
superposition is intact. And Bruno would claim that it is never
broken. So your awareness (or not) of the facts about the world or 
not

does not affect anything.

If it isn't then it's not clear if that's the case or not and one 
needs to take a deeper look. However, it's then also a 
philosophical issue as probabilities are not going to be 
different from a classical analysis.


There is nothing wrong to invoke consciousness, walking away from 
that just because that's the popular thing to do, doesn't make it 
right. What I'm arguing for 

Re: Consistency of Postulates of QM

[smitra]

On 14-12-2017 22:35, Bruce Kellett wrote:

On 15/12/2017 6:25 am, John Clark wrote:


On Wed, Dec 13, 2017 at 10:38 PM,  wrote:


​ > ​ I notice you don't gave a damn about having a non
falsifiable theory.


David Deutsch proposed a test of Many Worlds about 30 years ago in
his book "The Ghost In The Atom", but
​ it ​ would be very difficult to perform. The reason it's so
difficult to test is not
​ the ​M any
​ World's
​ ​ theory fault, the reason is that the conventional view says
that conscious
​ ​ observers obey different laws of physics, many worlds says
they do not, so
​ ​ to test who's right we need a mind that uses quantum
properties.
​ ​ Quantum Computers have advanced enormously over the last 30
years
​ so​ I wouldn't be surprised if it or something very much like
it
​ is ​ actually performed in the decade or two.

​ An intelligent quantum computer shoots
​ ​ photons at a metal plate
​ ​ one at a time
​ ​ that has 2 small slits in
​ ​it, and then the photons hit a photographic plate.
​ ​ Nobody looks at the photographic plate till the very end of
the experiment.
​ The quantum mind has detectors near each slit so it knows which
slit
​ ​ the various electrons went through.
​ ​ After each photon passes the slits but before they hit the
photographic plate the quantum mind signs a document
​ ​ saying that it has observed each and every
​ photon​ and knows
​ which​ slit each
​ ​ photon
​ ​ went through. It is very important that the document does
not say
​ ​ which slit
​ ​ any
​ ​photon went through, it only says that they went through
​ ​ one slit
​ ​ and one slit only and the mind has knowledge of which one.
​ ​ There is a signed document to this effect for every photon
it shot.

Now the mind uses
​ ​ quantum erasure to completely destroy
​ its​ memory of
​ which slit any of the ​photons went through; t he only
​ ​ part remaining is the document
​ which states that each photon went through one and only one slit
and the mind (at the time) knew which one. ​ Now develop the
photographic plate and look at it.
​ I​ f you see interference bands then the many world
interpretation is
​ ​ correct. If you do not see interference bands then there are
no worlds but
​ ​ this one and the conventional
​ quantum ​ interpretation is correct.

​This works because ​in the Copenhagen interpretation when the
results of a measurement enters the consciousness of an observer the
wave function collapses, in effect all the universes except one
disappear without a trace so you get no interference. In the many
worlds model all the other worlds will converge back into one
universe because information on which slit the various photons went
through was the only thing that made one universe different from
another, so when that was erased they became identical again and
merged, but their influence will still be felt, you'll see
indications that the photon went through slot A only and indications
it went through slot B only, and that's what causes interference.


 I think this argument pre-dates the work by Zeh and Zurek developing
the idea of decoherence. Decoherence remove the oddities of Copenhagen
as presented above in that it is not consciousness that does the work,
but decoherence. Bohr was saying essentially the same thing (though he
didn't know the words) when he talked about the importance of the
whole experimental set up.

 That aside, Deutsch's idea fails because he has not fully implemented
quantum erasure. If a record exists of the fact that a 'welcher weg'
measurement was made, entanglement of the rest of the world with the
result of that measurement is not erased by merely resetting the
memory of the mind or computer. So in the proposed experiment, the
interference pattern is absent, and it is not a proper 'delayed
choice' situation.

Deutsch has also given a rigorous variant of this that I summarized in 
my paper. It is possible in theory to experimentally prove the existence 
of other branches where a different measurement result was obtained. 
It's only impossible FAPP.


Saibal

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Re: Consistency of Postulates of QM

[smitra]

On 14-12-2017 22:39, Bruce Kellett wrote:

On 14/12/2017 11:20 pm, smitra wrote:

On 14-12-2017 12:43, Bruce Kellett wrote:

On 14/12/2017 9:23 pm, smitra wrote:

On 14-12-2017 02:35, Bruce Kellett wrote:

On 14/12/2017 11:52 am, smitra wrote:

On 13-12-2017 22:55, Bruce Kellett wrote:

On 14/12/2017 8:23 am, smitra wrote:


So, let's examine this more closely. We start with a state that 
is a superposition of branches that each undergo classical 
evolution, so I'm not now appealing to the arguments in the 
paper by Albrecht. Then we end up with a state of the form:


 Sum over j [|heads(j)>|env(heads,j)> +

 Sum over j |tails(j)>|env(tails,j)>]

where j enumerates microstates of the coin and the state of the 
environment in each sector where the coin is heads or tails 
depends on the microstate of the coin. The coin states are not 
normalized, the norms are chosen to yield the correct 
probabilities.  E.g. if tails has zero probability then all the 
|tail(j)> are given a norm of zero. So, the above expression is 
completely general.


Now, I'm part of the environment, so we can write:

|env(X,j)> = Sum over k of |me(X,Y,j,k)>|env'(X,Y,j,k)>

where X is heads or tails, Y, denotes my macrostate that I'll 
define below, j denotes the microstate of the coin and k sums 
over microstates corresponding to macrostate Y.


This splitting of my state into a macrostate Y and microstate k 
is in principle arbitrary, we can choose this splitting such 
that Y keep tracts of what I'm aware of and then k takes into 
account all the other degrees of freedom in my body and brain 
that I'm not aware of. E.g. if I were a digital computer then Y 
would correspond to some bitstring defined by the computational 
state of the computer and we then sum over all the possible 
microstates that correspond to some fixed macrostate.


Then when I'm not yet aware of the result of the coin throw, we 
have:


|me(X,Y,j,k)> = |Awareness(Y)>|body(X,Y,j,k)>

where Y contains all the information that I am aware of, and 
that doesn't include the result if the coin throw nor 
information contained only at the microscopic scale. So, 
Awareness (Y) for a given Y defines who I am, where I am , and 
what I'm experiencing.


It should be clear that despite decoherence, |Awareness(Y)> will 
factor out of the global superposition as it doesn't depend on 
X, k and j.


So, given what I know, I cannot tell in which branch I am. 
Therefore unless all the branches corresponding to one outcome 
have zero norm,  I will have copies in both branches.


There is just no way that all the information describing what 
I'm aware of at some moment is going to constrain how someone 
else can throw a coin to such a degree that the outcome will be 
fixed.


So the end point of your analysis is that you can't see how it 
could
be possible that you are not right? The outcome is fixed -- and 
the

same -- in all worlds in which you participate!

But it is quite easy to see what is going on. Since it is all
independent of your awareness, we can factor that out of the
summations. And you still do not get a coherent superposition 
from a

decoherent mixture. What goes on in the world is independent of
whether or not the rock on the floor is aware of it or not. You 
are
not in a position any different from that of said rock. Look at 
the

expansion for Schrödinger's cat:

  |nucleus>|box>|cat>you>|environment> -->

 {|decayed>|poison spilt>|cat dead>|You>|environment records dead 
cat>
 + |undecayed>|poison intact>|cat alive>|You>|environment records 
live cat>}


You can see that your state does not change (is irrelevant) until 
you
interact with the environment in such a way that your 
consciousness
becomes entangled with the state of the cat. This is not 
mysterious,

and it is not changed just because you claim there is some magic
associated with consciousness that makes a difference. You are 
just
reverting to Copenhagen or many minds where consciousness is 
necessary

for the understanding of QM.



The lack of coherence is not relevant unless it affects the two 
states denoted by |you>.


That is not true.

If you have a coherent superposition then it's clear that the two 
|you>'s are identical.


No, it is not. In the above expansion of the cat scenario, I have a
coherent superposition of live and dead cats -- in different 
branches

of course, but until decoherence separates the worlds, the
superposition is intact. And Bruno would claim that it is never
broken. So your awareness (or not) of the facts about the world or 
not

does not affect anything.

If it isn't then it's not clear if that's the case or not and one 
needs to take a deeper look. However, it's then also a 
philosophical issue as probabilities are not going to be different 
from a classical analysis.


There is nothing wrong to invoke consciousness, walking away from 
that just because that's the popular thing to do, doesn't make it 
right. What I'm arguing for is to define conscious experience as 

Re: Consistency of Postulates of QM

[Bruce Kellett]

On 14/12/2017 11:20 pm, smitra wrote:

On 14-12-2017 12:43, Bruce Kellett wrote:

On 14/12/2017 9:23 pm, smitra wrote:

On 14-12-2017 02:35, Bruce Kellett wrote:

On 14/12/2017 11:52 am, smitra wrote:

On 13-12-2017 22:55, Bruce Kellett wrote:

On 14/12/2017 8:23 am, smitra wrote:


So, let's examine this more closely. We start with a state that 
is a superposition of branches that each undergo classical 
evolution, so I'm not now appealing to the arguments in the 
paper by Albrecht. Then we end up with a state of the form:


 Sum over j [|heads(j)>|env(heads,j)> +

 Sum over j |tails(j)>|env(tails,j)>]

where j enumerates microstates of the coin and the state of the 
environment in each sector where the coin is heads or tails 
depends on the microstate of the coin. The coin states are not 
normalized, the norms are chosen to yield the correct 
probabilities.  E.g. if tails has zero probability then all the 
|tail(j)> are given a norm of zero. So, the above expression is 
completely general.


Now, I'm part of the environment, so we can write:

|env(X,j)> = Sum over k of |me(X,Y,j,k)>|env'(X,Y,j,k)>

where X is heads or tails, Y, denotes my macrostate that I'll 
define below, j denotes the microstate of the coin and k sums 
over microstates corresponding to macrostate Y.


This splitting of my state into a macrostate Y and microstate k 
is in principle arbitrary, we can choose this splitting such 
that Y keep tracts of what I'm aware of and then k takes into 
account all the other degrees of freedom in my body and brain 
that I'm not aware of. E.g. if I were a digital computer then Y 
would correspond to some bitstring defined by the computational 
state of the computer and we then sum over all the possible 
microstates that correspond to some fixed macrostate.


Then when I'm not yet aware of the result of the coin throw, we 
have:


|me(X,Y,j,k)> = |Awareness(Y)>|body(X,Y,j,k)>

where Y contains all the information that I am aware of, and 
that doesn't include the result if the coin throw nor 
information contained only at the microscopic scale. So, 
Awareness (Y) for a given Y defines who I am, where I am , and 
what I'm experiencing.


It should be clear that despite decoherence, |Awareness(Y)> will 
factor out of the global superposition as it doesn't depend on 
X, k and j.


So, given what I know, I cannot tell in which branch I am. 
Therefore unless all the branches corresponding to one outcome 
have zero norm,  I will have copies in both branches.


There is just no way that all the information describing what 
I'm aware of at some moment is going to constrain how someone 
else can throw a coin to such a degree that the outcome will be 
fixed.


So the end point of your analysis is that you can't see how it could
be possible that you are not right? The outcome is fixed -- and the
same -- in all worlds in which you participate!

But it is quite easy to see what is going on. Since it is all
independent of your awareness, we can factor that out of the
summations. And you still do not get a coherent superposition from a
decoherent mixture. What goes on in the world is independent of
whether or not the rock on the floor is aware of it or not. You are
not in a position any different from that of said rock. Look at the
expansion for Schrödinger's cat:

  |nucleus>|box>|cat>you>|environment> -->

 {|decayed>|poison spilt>|cat dead>|You>|environment records dead 
cat>
 + |undecayed>|poison intact>|cat alive>|You>|environment records 
live cat>}


You can see that your state does not change (is irrelevant) until 
you

interact with the environment in such a way that your consciousness
becomes entangled with the state of the cat. This is not mysterious,
and it is not changed just because you claim there is some magic
associated with consciousness that makes a difference. You are just
reverting to Copenhagen or many minds where consciousness is 
necessary

for the understanding of QM.



The lack of coherence is not relevant unless it affects the two 
states denoted by |you>.


That is not true.

If you have a coherent superposition then it's clear that the two 
|you>'s are identical.


No, it is not. In the above expansion of the cat scenario, I have a
coherent superposition of live and dead cats -- in different branches
of course, but until decoherence separates the worlds, the
superposition is intact. And Bruno would claim that it is never
broken. So your awareness (or not) of the facts about the world or not
does not affect anything.

If it isn't then it's not clear if that's the case or not and one 
needs to take a deeper look. However, it's then also a 
philosophical issue as probabilities are not going to be different 
from a classical analysis.


There is nothing wrong to invoke consciousness, walking away from 
that just because that's the popular thing to do, doesn't make it 
right. What I'm arguing for is to define conscious experience as 
the computational state of the relevant machine (or 

Re: Consistency of Postulates of QM

[Bruce Kellett]

On 15/12/2017 6:25 am, John Clark wrote:
On Wed, Dec 13, 2017 at 10:38 PM, >wrote:


​ > ​
I notice you don't gave a damn about having a non falsifiable theory.


David Deutsch proposed a test of Many Worlds about 30 years ago in his 
book "The Ghost In The Atom", but

​ it ​
would be very difficult to perform. The reason it's so difficult to 
test is not

​ the ​M
any
​ World's
​ ​
theory fault, the reason is that the conventional view says that 
conscious

​ ​
observers obey different laws of physics, many worlds says they do 
not, so

​ ​
to test who's right we need a mind that uses quantum properties.
​ ​
Quantum Computers have advanced enormously over the last 30 years
​ so​
 I wouldn't be surprised if it or something very much like it
​ is ​
actually performed in the decade or two.

​
An intelligent quantum computer shoots
​ ​
photons at a metal plate
​ ​
one at a time
​ ​
that has 2 small slits in
​ ​it,
and then the photons hit a photographic plate.
​ ​
Nobody looks at the photographic plate till the very end of the 
experiment.

​
The quantum mind has detectors near each slit so it knows which slit
​ ​
the various electrons went through.
​ ​
After each photon passes the slits but before they hit the 
photographic plate the quantum mind signs a document

​ ​
saying that it has observed each and every
​ photon​
 and knows
​ which​
 slit each
​ ​
photon
​ ​
went through. It is very important that the document does not say
​ ​
which slit
​ ​
any
​ ​photon
 went through, it only says that they went through
​ ​
one slit
​ ​
and one slit only and the mind has knowledge of which one.
​ ​
There is a signed document to this effect for every photon it shot.

Now the mind uses
​ ​
quantum erasure to completely destroy
​ its​
 memory of
​ which slit any of the ​photons went through; t
he only
​ ​
part remaining is the document
​ which states that each photon went through one and only one slit and 
the mind (at the time) knew which one. ​

Now develop the photographic plate and look at it.
​ I​
f you see interference bands then the many world interpretation is
​ ​
correct. If you do not see interference bands then there are no worlds 
but

​ ​
this one and the conventional
​ quantum ​
interpretation is correct.

​This works because ​in the Copenhagen interpretation when the results 
of a measurement enters the consciousness of an observer the wave 
function collapses, in effect all the universes except one disappear 
without a trace so you get no interference. In the many worlds model 
all the other worlds will converge back into one universe because 
information on which slit the various photons went through was the 
only thing that made one universe different from another, so when that 
was erased they became identical again and merged, but their influence 
will still be felt, you'll see indications that the photon went 
through slot A only and indications it went through slot B only, and 
that's what causes interference.


I think this argument pre-dates the work by Zeh and Zurek developing the 
idea of decoherence. Decoherence remove the oddities of Copenhagen as 
presented above in that it is not consciousness that does the work, but 
decoherence. Bohr was saying essentially the same thing (though he 
didn't know the words) when he talked about the importance of the whole 
experimental set up.


That aside, Deutsch's idea fails because he has not fully implemented 
quantum erasure. If a record exists of the fact that a 'welcher weg' 
measurement was made, entanglement of the rest of the world with the 
result of that measurement is not erased by merely resetting the memory 
of the mind or computer. So in the proposed experiment, the interference 
pattern is absent, and it is not a proper 'delayed choice' situation.


Bruce

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Re: Consistency of Postulates of QM

[John Clark]

On Wed, Dec 13, 2017 at 10:38 PM,  wrote:

​> ​
> I notice you don't gave a damn about having a non falsifiable theory.
>

David Deutsch proposed a test of Many Worlds about 30 years ago in his book
"The Ghost In The Atom", but
​it ​
would be very difficult to perform. The reason it's so difficult to test is
not
​the ​M
any
​World's
​ ​
theory fault, the reason is that the conventional view says that conscious
​ ​
observers obey different laws of physics, many worlds says they do not, so
​ ​
to test who's right we need a mind that uses quantum properties.
​ ​
Quantum Computers have advanced enormously over the last 30 years
​so​
 I wouldn't be surprised if it or something very much like it
​is ​
actually performed in the decade or two.

​
An intelligent quantum computer shoots
​ ​
photons at a metal plate
​ ​
one at a time
​ ​
that has 2 small slits in
​ ​it,
and then the photons hit a photographic plate.
​ ​
Nobody looks at the photographic plate till the very end of the experiment.
​
The quantum mind has detectors near each slit so it knows which slit
​ ​
the various electrons went through.
​ ​
After each photon passes the slits but before they hit the photographic
plate the quantum mind signs a document
​ ​
saying that it has observed each and every
​photon​
 and knows
​which​
 slit each
​ ​
photon
​ ​
went through. It is very important that the document does not say
​ ​
which slit
​ ​
any
​ ​photon
 went through, it only says that they went through
​ ​
one slit
​ ​
and one slit only and the mind has knowledge of which one.
​ ​
There is a signed document to this effect for every photon it shot.

Now the mind uses
​ ​
quantum erasure to completely destroy
​its​
 memory of
​which slit any of the ​photons went through; t
he only
​ ​
part remaining is the document
​ which states that each photon went through one and only one slit and the
mind (at the time) knew which one. ​
Now develop the photographic plate and look at it.
​I​
f you see interference bands then the many world interpretation is
​ ​
correct. If you do not see interference bands then there are no worlds but
​ ​
this one and the conventional
​quantum ​
interpretation is correct.

​This works because ​in the Copenhagen interpretation when the results of a
measurement enters the consciousness of an observer the wave function
collapses, in effect all the universes except one disappear without a trace
so you get no interference. In the many worlds model all the other worlds
will converge back into one universe because information on which slit
the various photons went through was the only thing that made one universe
different from another, so when that was erased they became identical again
and merged, but their influence will still be felt, you'll see indications
that the photon went through slot A only and indications it went through
slot B only, and that's what causes interference.

  John K Clark

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Re: Schrodinger's cat problem; proposed solution

[Jason Resch]

The solution was proposed by Everett in 1957, collapse is a subjective
illusion.  The dead cat and its history of decomposing for the previous
hour does not materialize out of nothing from the mere act of looking at it.


No measurement is made of the cat, the Geiger counter, or the atom, by
anyone outside the isolated system of the box, so according to the
Copenhagen Interpretation the superposition does not collapse. The cat is
both alive and dead. That is, until someone opens the door to peek inside.
In that instant, the wave function collapses and the system randomly
“decides” whether the cat is alive or dead.

If the state collapses to that of the dead cat, what happens to the
experiences of the cat who was in the superposition of being alive and dead
over the past hour? Do they suddenly vanish as if they never happened at
all? Perhaps they never existed in the first place, as Bohr’s anti-realist
approach would answer. But this leads to another problem: if the cat is
observed to be alive, do all of its memories and experiences over the past
hour suddenly pop into existence? Is the cat’s experience of 15 minutes ago
ever experienced?

It is one thing to believe that microscopic particles might be in two
different states at once, but quite another to believe the same for a large
and complex system, such as a cat. The CI implies that a living, breathing
cat, with a consistent history and memories of the previous hour, can
instantly materialize from the simple act of observation.

Schrödinger's experiment has also been extended to highlight other
problems. The mathematical physicist Eugene Wigner discussed a thought
experiment known as Wigner’s friend. In it, Wigner’s friend is in a room
that is sealed off from the rest of the world and in that room is a box
containing Schrödinger's cat. The friend opens the box after an hour and
notices whether or not the cat is alive. Sometime later, Wigner opens the
door to the room to check on his friend. When does the wave function
collapse, when the friend checks on the cat, or when Wigner checks on his
friend? If it is when the friend checks on the cat, then the isolated
system, unobserved by Wigner, has already collapsed (in contradiction to
the CI). Yet, if it does not collapse for the friend checking on the cat,
this is another contradiction, for he has made an observation of a system
in a superposition. The CI seems to have difficulties handling multiple
observers.

If one takes the stance that the first conscious entity to experience the
result of a measurement causes collapse, whether isolated or not, this
still leaves the problem of large macroscopic systems with complex
histories popping into existence through observation. If we replace the cat
with some unconscious device, like a sensor that prints off a receipt with
the result of whether or not the poison was released, then a conscious
observer opening the box causes the instantaneous appearance of the print
out, oddly, with ink that has long-since dried. It has a consistent history
seemingly invented at once.

Einstein was most impressed with Schrödinger's paper, and in 1950 wrote
Schrödinger a letter of praise, saying “You are the only contemporary
physicist, besides Laue, who sees that one cannot get around the assumption
of reality, if only one is honest. Most of them simply do not see what sort
of risky game they are playing with reality—reality as something
independent of what is experimentally established. Their interpretation is,
however, refuted most elegantly by your system of radioactive atom +
amplifier + charge of gunpowder + cat in a box, in which the psi- function
of the system contains both the cat alive and blown to bits. Nobody really
doubts that the presence or absence of the cat is something independent of
the act of observation.”

Einstein never accepted the quantum mechanics as a complete theory. To the
end of his life he searched for a theory that better fit his ideals of
realism, causality and determinism. But the answer he sought was there all
along: in the equations of quantum mechanics. Consciously or unconsciously,
however, the answer was simply too strange for anyone to consider, even for
a moment. It was not until 1957, more than three decades after quantum
mechanics was formulated, that anyone was bold enough to point out the
answer that was staring everyone in the face. That person was Hugh Everett
III.


Jason

On Tue, Dec 12, 2017 at 3:04 PM,  wrote:

> Not every superposition of states implies interference. Connect the dots.
> AG
>
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Re: Consistency of Postulates of QM

[smitra]

On 14-12-2017 12:43, Bruce Kellett wrote:

On 14/12/2017 9:23 pm, smitra wrote:

On 14-12-2017 02:35, Bruce Kellett wrote:

On 14/12/2017 11:52 am, smitra wrote:

On 13-12-2017 22:55, Bruce Kellett wrote:

On 14/12/2017 8:23 am, smitra wrote:


So, let's examine this more closely. We start with a state that is 
a superposition of branches that each undergo classical evolution, 
so I'm not now appealing to the arguments in the paper by 
Albrecht. Then we end up with a state of the form:


 Sum over j [|heads(j)>|env(heads,j)> +

 Sum over j |tails(j)>|env(tails,j)>]

where j enumerates microstates of the coin and the state of the 
environment in each sector where the coin is heads or tails 
depends on the microstate of the coin. The coin states are not 
normalized, the norms are chosen to yield the correct 
probabilities.  E.g. if tails has zero probability then all the 
|tail(j)> are given a norm of zero. So, the above expression is 
completely general.


Now, I'm part of the environment, so we can write:

|env(X,j)> = Sum over k of |me(X,Y,j,k)>|env'(X,Y,j,k)>

where X is heads or tails, Y, denotes my macrostate that I'll 
define below, j denotes the microstate of the coin and k sums over 
microstates corresponding to macrostate Y.


This splitting of my state into a macrostate Y and microstate k is 
in principle arbitrary, we can choose this splitting such that Y 
keep tracts of what I'm aware of and then k takes into account all 
the other degrees of freedom in my body and brain that I'm not 
aware of. E.g. if I were a digital computer then Y would 
correspond to some bitstring defined by the computational state of 
the computer and we then sum over all the possible microstates 
that correspond to some fixed macrostate.


Then when I'm not yet aware of the result of the coin throw, we 
have:


|me(X,Y,j,k)> = |Awareness(Y)>|body(X,Y,j,k)>

where Y contains all the information that I am aware of, and that 
doesn't include the result if the coin throw nor information 
contained only at the microscopic scale. So, Awareness (Y) for a 
given Y defines who I am, where I am , and what I'm experiencing.


It should be clear that despite decoherence, |Awareness(Y)> will 
factor out of the global superposition as it doesn't depend on X, 
k and j.


So, given what I know, I cannot tell in which branch I am. 
Therefore unless all the branches corresponding to one outcome 
have zero norm,  I will have copies in both branches.


There is just no way that all the information describing what I'm 
aware of at some moment is going to constrain how someone else can 
throw a coin to such a degree that the outcome will be fixed.


So the end point of your analysis is that you can't see how it 
could

be possible that you are not right? The outcome is fixed -- and the
same -- in all worlds in which you participate!

But it is quite easy to see what is going on. Since it is all
independent of your awareness, we can factor that out of the
summations. And you still do not get a coherent superposition from 
a

decoherent mixture. What goes on in the world is independent of
whether or not the rock on the floor is aware of it or not. You are
not in a position any different from that of said rock. Look at the
expansion for Schrödinger's cat:

  |nucleus>|box>|cat>you>|environment> -->

 {|decayed>|poison spilt>|cat dead>|You>|environment records dead 
cat>
 + |undecayed>|poison intact>|cat alive>|You>|environment records 
live cat>}


You can see that your state does not change (is irrelevant) until 
you

interact with the environment in such a way that your consciousness
becomes entangled with the state of the cat. This is not 
mysterious,

and it is not changed just because you claim there is some magic
associated with consciousness that makes a difference. You are just
reverting to Copenhagen or many minds where consciousness is 
necessary

for the understanding of QM.



The lack of coherence is not relevant unless it affects the two 
states denoted by |you>.


That is not true.

If you have a coherent superposition then it's clear that the two 
|you>'s are identical.


No, it is not. In the above expansion of the cat scenario, I have a
coherent superposition of live and dead cats -- in different branches
of course, but until decoherence separates the worlds, the
superposition is intact. And Bruno would claim that it is never
broken. So your awareness (or not) of the facts about the world or 
not

does not affect anything.

If it isn't then it's not clear if that's the case or not and one 
needs to take a deeper look. However, it's then also a philosophical 
issue as probabilities are not going to be different from a  
classical analysis.


There is nothing wrong to invoke consciousness, walking away from 
that just because that's the popular thing to do, doesn't make it 
right. What I'm arguing for is to define conscious experience as the 
computational state of the relevant machine (or brain), which is 
then given by some 

Re: Consistency of Postulates of QM

[Bruce Kellett]

On 14/12/2017 9:23 pm, smitra wrote:

On 14-12-2017 02:35, Bruce Kellett wrote:

On 14/12/2017 11:52 am, smitra wrote:

On 13-12-2017 22:55, Bruce Kellett wrote:

On 14/12/2017 8:23 am, smitra wrote:


So, let's examine this more closely. We start with a state that is 
a superposition of branches that each undergo classical evolution, 
so I'm not now appealing to the arguments in the paper by 
Albrecht. Then we end up with a state of the form:


 Sum over j [|heads(j)>|env(heads,j)> +

 Sum over j |tails(j)>|env(tails,j)>]

where j enumerates microstates of the coin and the state of the 
environment in each sector where the coin is heads or tails 
depends on the microstate of the coin. The coin states are not 
normalized, the norms are chosen to yield the correct 
probabilities.  E.g. if tails has zero probability then all the 
|tail(j)> are given a norm of zero. So, the above expression is 
completely general.


Now, I'm part of the environment, so we can write:

|env(X,j)> = Sum over k of |me(X,Y,j,k)>|env'(X,Y,j,k)>

where X is heads or tails, Y, denotes my macrostate that I'll 
define below, j denotes the microstate of the coin and k sums over 
microstates corresponding to macrostate Y.


This splitting of my state into a macrostate Y and microstate k is 
in principle arbitrary, we can choose this splitting such that Y 
keep tracts of what I'm aware of and then k takes into account all 
the other degrees of freedom in my body and brain that I'm not 
aware of. E.g. if I were a digital computer then Y would 
correspond to some bitstring defined by the computational state of 
the computer and we then sum over all the possible microstates 
that correspond to some fixed macrostate.


Then when I'm not yet aware of the result of the coin throw, we have:

|me(X,Y,j,k)> = |Awareness(Y)>|body(X,Y,j,k)>

where Y contains all the information that I am aware of, and that 
doesn't include the result if the coin throw nor information 
contained only at the microscopic scale. So, Awareness (Y) for a 
given Y defines who I am, where I am , and what I'm experiencing.


It should be clear that despite decoherence, |Awareness(Y)> will 
factor out of the global superposition as it doesn't depend on X, 
k and j.


So, given what I know, I cannot tell in which branch I am. 
Therefore unless all the branches corresponding to one outcome 
have zero norm,  I will have copies in both branches.


There is just no way that all the information describing what I'm 
aware of at some moment is going to constrain how someone else can 
throw a coin to such a degree that the outcome will be fixed.


So the end point of your analysis is that you can't see how it could
be possible that you are not right? The outcome is fixed -- and the
same -- in all worlds in which you participate!

But it is quite easy to see what is going on. Since it is all
independent of your awareness, we can factor that out of the
summations. And you still do not get a coherent superposition from a
decoherent mixture. What goes on in the world is independent of
whether or not the rock on the floor is aware of it or not. You are
not in a position any different from that of said rock. Look at the
expansion for Schrödinger's cat:

  |nucleus>|box>|cat>you>|environment> -->

 {|decayed>|poison spilt>|cat dead>|You>|environment records dead cat>
 + |undecayed>|poison intact>|cat alive>|You>|environment records 
live cat>}


You can see that your state does not change (is irrelevant) until you
interact with the environment in such a way that your consciousness
becomes entangled with the state of the cat. This is not mysterious,
and it is not changed just because you claim there is some magic
associated with consciousness that makes a difference. You are just
reverting to Copenhagen or many minds where consciousness is necessary
for the understanding of QM.



The lack of coherence is not relevant unless it affects the two 
states denoted by |you>.


That is not true.

If you have a coherent superposition then it's clear that the two 
|you>'s are identical.


No, it is not. In the above expansion of the cat scenario, I have a
coherent superposition of live and dead cats -- in different branches
of course, but until decoherence separates the worlds, the
superposition is intact. And Bruno would claim that it is never
broken. So your awareness (or not) of the facts about the world or not
does not affect anything.

If it isn't then it's not clear if that's the case or not and one 
needs to take a deeper look. However, it's then also a philosophical 
issue as probabilities are not going to be different from a  
classical analysis.


There is nothing wrong to invoke consciousness, walking away from 
that just because that's the popular thing to do, doesn't make it 
right. What I'm arguing for is to define conscious experience as the 
computational state of the relevant machine (or brain), which is 
then given by some bistring. This can then be included in the 
quantum state 

Re: Consistency of Postulates of QM

[smitra]

On 14-12-2017 02:35, Bruce Kellett wrote:

On 14/12/2017 11:52 am, smitra wrote:

On 13-12-2017 22:55, Bruce Kellett wrote:

On 14/12/2017 8:23 am, smitra wrote:

On 12-12-2017 23:13, Bruce Kellett wrote:

On 13/12/2017 2:12 am, smitra wrote:

On 12-12-2017 12:33, Bruce Kellett wrote:

On 12/12/2017 9:46 pm, smitra wrote:


Yes, it's only an estimation but it yields a good order of 
magnitude estimate for the center of mass. What the calculation 
shows is that quantum superpositions do exists at the 
macroscopic level and these can then be amplified by chaotic 
dynamics. Of course,  it then becomes incoherent, but in the MWI 
that's besides the point.


MWI splitting depends on coherence, so it is certainly not beside 
the

point for the coin toss.


It doesn't depend on coherence. Why would it matter if the state 
of the coin gets entangled with a zillion other environmental 
degrees of freedom? The dynamics according to unitary time 
evolution leads toa  superposition, no matter how many degrees of 
freedom are involved in the entanglement.


You are missing the point. Splitting according to the Schrödinger
equation does depend on coherence. The decoherence that entangles 
the

coin with a zillion other environmental degrees of freedom occurs
after the splitting. Given decoherence, the process is irreversible
FAPP, which means that there is no practical way, by design or 
chance,
that a decohered state can recohere. Sure, in the many worlds of 
MWI
the superposition, if it once existed, is still intact. But if no 
such
superposition ever existed, then it can't be created from 
non-coherent

interactions.

So Schrödinger's cat was once a coherent state of a cat in a box, 
and

the splitting occurs with the decay of a nucleus; decoherent
entanglement then leads to the splitting of worlds FAPP. But given 
an

arbitrary coin, it is already non-coherently entangled with many
environmental degrees of freedom, but there is no state that can 
lead
to {heads>+|tails>} in a unitary manner, so there is no state that 
can
then evolve into a splitting and decoherence into worlds 
distinguished

by either |heads> or |tails>. If you think that there is, write out
the schematic sequence of states evolving under the SE that leads 
to

this result.


So, let's examine this more closely. We start with a state that is a 
superposition of branches that each undergo classical evolution, so 
I'm not now appealing to the arguments in the paper by Albrecht. 
Then we end up with a state of the form:


 Sum over j [|heads(j)>|env(heads,j)> +

 Sum over j |tails(j)>|env(tails,j)>]

where j enumerates microstates of the coin and the state of the 
environment in each sector where the coin is heads or tails depends 
on the microstate of the coin. The coin states are not normalized, 
the norms are chosen to yield the correct probabilities.  E.g. if 
tails has zero probability then all the |tail(j)> are given a norm 
of zero. So, the above expression is completely general.


Now, I'm part of the environment, so we can write:

|env(X,j)> = Sum over k of |me(X,Y,j,k)>|env'(X,Y,j,k)>

where X is heads or tails, Y, denotes my macrostate that I'll define 
below, j denotes the microstate of the coin and k sums over 
microstates corresponding to macrostate Y.


This splitting of my state into a macrostate Y and microstate k is 
in principle arbitrary, we can choose this splitting such that Y 
keep tracts of what I'm aware of and then k takes into account all 
the other degrees of freedom in my body and brain that I'm not aware 
of. E.g. if I were a digital computer then Y would correspond to 
some bitstring defined by the computational state of the computer 
and we then sum over all the possible microstates that correspond to 
some fixed macrostate.


Then when I'm not yet aware of the result of the coin throw, we 
have:


|me(X,Y,j,k)> = |Awareness(Y)>|body(X,Y,j,k)>

where Y contains all the information that I am aware of, and that 
doesn't include the result if the coin throw nor information 
contained only at the microscopic scale. So, Awareness (Y) for a 
given Y defines who I am, where I am , and what I'm experiencing.


It should be clear that despite decoherence, |Awareness(Y)> will 
factor out of the global superposition as it doesn't depend on X, k 
and j.


So, given what I know, I cannot tell in which branch I am. Therefore 
unless all the branches corresponding to one outcome have zero norm, 
 I will have copies in both branches.


There is just no way that all the information describing what I'm 
aware of at some moment is going to constrain how someone else can 
throw a coin to such a degree that the outcome will be fixed.


So the end point of your analysis is that you can't see how it could
be possible that you are not right? The outcome is fixed -- and the
same -- in all worlds in which you participate!

But it is quite easy to see what is going on. Since it is all
independent of your awareness, we can factor that out of 

Re: Consistency of Postulates of QM

[agrayson2000]

On Thursday, December 14, 2017 at 1:41:37 AM UTC, Brent wrote:
>
>
>
> On 12/13/2017 5:24 PM, agrays...@gmail.com  wrote:
>
>
>
> On Wednesday, December 13, 2017 at 10:44:14 PM UTC, Brent wrote: 
>>
>>
>>
>> On 12/13/2017 2:20 PM, agrays...@gmail.com wrote:
>>
>>
>>
>> On Wednesday, December 13, 2017 at 9:15:36 PM UTC, Brent wrote: 
>>>
>>>
>>>
>>> On 12/13/2017 2:45 AM, agrays...@gmail.com wrote:
>>>
>>> * BUT for a nucleus of a radioactive element, the nucleus is never 
>>> Decayed and Undecayed SIMULTANEOUSLY.*
>>>
>>> Sure it is.  It's in a coherent superposition of those states until it 
>>> interacts with the environment.
>>>
>>> Brent
>>>
>>
>> * That's the conventional QM wisdom and the cause of the paradox of a cat 
>> Alive and Dead simultaneously. As I explained, the fallacy is rooted in an 
>> unjustified generalization of the double slit experiment where the 
>> probability waves do, in fact, exist simultaneously.  What waves do you 
>> claim are interacting for the radioactive nucleus to produce coherence? 
>> Tell me about them. I am from Missouri. AG*
>>
>>
>> You seem to think that coherence requires two different waves.  This is 
>> the wrong way to look at it.  In Young's slits experiment there is only one 
>> wave, which goes through both slits and interferes with itself.  
>>
>
>
> *That's exactly how I see it! Interference requires two waves which 
> interact with each other. *
>
>
> *NO.  This is false! * *There are not two waves.*  You can write it as 
> two parts, just as you can write a description of an ocean wave as the part 
> on your left and the part on your right.  But so long as they are coherent, 
> maintaining a fixed phase relation, they are one wave.
>
>
> *This is exactly what we see in Young's slits experiments. AG  *
>
>> And unstable nucleus has a probability amplitude that includes a 
>> "decayed" part and a "not decayed" part.  It's a tunneling problem.
>>
>
> *I don't doubt the existence of amplitudes. What I do doubt. and in fact 
> deny, is interference between two waves that don't exist simultaneously. *
>
>
> You keep referring to two waves. * There are not two waves.  *There's 
> only one wave which interferes with itself.  It is typically written as 
> |not-decayed> + |decayed>, but that's just a choice of basis.  It could as 
> well be written |unstable nucleus>.
>

*How can one wave interfere with itself? Using double slit model, the one 
wave you're referring to, must somehow split. How does that splitting occur 
in a nuclear decay? If no splitting, then the concept of interference makes 
no sense. Without interference, the cat is never simultaneously Alive and 
Dead. AG*
 

> Us

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