Re: What day is it?

[Stathis Papaioannou]

> On 24 Sep 2015, at 6:07 PM, Bruce Kellett  wrote:
> 
>> On 25/09/2015 12:53 am, Stathis Papaioannou wrote:
>>> On Wednesday, 23 September 2015, Bruce Kellett  
>>> wrote:
 On 24/09/2015 4:02 am, Jason Resch wrote:
 On Tue, Sep 8, 2015 at 8:45 PM, Bruce Kellett  
 wrote:
> On 9/09/2015 1:29 pm, Jason Resch wrote:
>> 
>> On Tue, Sep 8, 2015 at 9:44 PM, Bruce Kellett 
>>  wrote:
>>> I presume you mean that the world is duplicated on each toss, with one 
>>> branch showing each outcome. We are 
>>> back to the dreaded "person duplication" problem. My opinion on this is 
>>> that on such a duplication, two new persons are created, so the 
>>> probability that the original person will see either heads or tails is 
>>> precisely zero, because that person no longer exists after the 
>>> duplication.
>> 
>> So if some aliens create a copy of you in Andromeda, then you cease to 
>> exist as a person?
> 
> Since I might know if they gathered the requisite information, it is not 
> an issue.
 
 I don't see how this follows. Are you saying you would cease to exist as a 
 person if a duplicate of you arose far away in this universe, or that you 
 would not cease to exist as a person?
>>> 
>>> The closest continuer account of personal identity would have no difficulty 
>>> with this. The remote "copy" is purely a matter of chance, which has no 
>>> physical or causal connection with you, so is not a continuer in the 
>>> required sense.
>> 
>> You present "closest continuer theory" as if it is obviously correct, and it 
>> is not. In any case, even granting the theory, why should the causal or 
>> physical connection make a difference? I've sometimes encountered this claim 
>> in these discussions but it is just ad hoc.
> 
> The theory is no more ad hoc than any other theory of personal identity. When 
> we seek to encapsulate an intuitive notion in language, any attempt could be 
> criticized as being ad hoc, so that charge is of no substance.

It's ad hoc to say that if one copy differed from the original by 1% and the 
other copy by 1.001%, then the 1% copy is the continuation of the original and 
the other copy a different person. It sounds like something made up by 
legislators rather than philosophers, like an arbitrary cutoff for a speed 
limit. If you can't "encapsulate an intuitive concept in language" then you 
should state that, or conclude that there is something wrong with the intuitive 
notion.

But my more substantive dispute was with your assertion that if a copy arose 
through random processes then it wouldn't really count as a continuation of the 
original. That's like saying that if car fell together from parts in a junkyard 
stirred up by a whirlwind it wouldn't really be a car - even though it 
functioned exactly like a car made in a factory.

>> Note: according to current comological models, space is infinite and 
>> uniform, which means infinite copies of you exist (though very far away).
> Such models make really quite strong assumptions about initial conditions.
 
 This all follows from thw concordance model of cosmology, which is the 
 "standard model" in cosmology. See:
 http://space.mit.edu/home/tegmark/PDF/multiverse_sciam.pdf
 
  
> You might well have an infinity of worlds with our present cosmology, but 
> they might all be copies of some bland, boring model with no intelligent 
> life.
 
 I don't think you grasp the implications of infinity. If there are 
 infinite worlds, there is effectively 100% probability 
 that an infinite number of them will be identical to this entire Earth as 
 you see it.
>>> 
>>> As I said, that assumes some regular distribution over initial conditions 
>>> --  condition for which we have no evidence whatsoever. So our universe - 
>>> and our particular personal existences - might be unique, even in an 
>>> infinite universe. There can be universes of zero probability measure.
>> 
>> The Copernican Principle in conjunction with the observation that the 
>> universe is uniform in all directions is enough.
> No, that is not enough. The Copernician principle is not a law of physics -- 
> or of anything else, for that matter. It is a useful heuristic, nothing more. 
> The so-called "uniformity of the universe (isotropy and homogeneity)" is also 
> nothing more than a useful approximation that can be used only on the largest 
> scales -- when you average over all local structure. Such arguments have no 
> force against the position I am arguing.

Your argument misses the point, which is that IF the universe is infinite and 
uniform THEN there would be infinite copies of you and everything you see, and 
you could not know which of these copies you were at any moment. There is 
reason to believe that in fact the universe is infinite and uniform; b

Re: What day is it?

[Brent Meeker]

On 9/24/2015 12:33 PM, John Clark wrote:



On Thu, Sep 24, 2015 at 1:24 PM, smitra > wrote:


​ > ​
The entropy is the logarithm of this number of states, more
precisely it is the amount of information that you would need to
specify in order to point out in which physical state the system
is actually in


​ Suppose you place a perfect cubic one mole diamond
​ in a large tank of oxygen, if you know the weight of the diamond and 
the position of just the carbon atom at one corner of the cube then 
you have all the information needed to know the position of every atom 
in the cube (assuming you know the chemistry of carbon bonds).

Now fire a LASER at the diamond and heat it up till it starts to burn,


Here you assume that you have only a coarse, macroscopic knowledge of 
the laser, the laser power source, and the oxygen atoms which is then 
the source of the entropy increase.


the ​atoms are no longer in a simple lattice but are distributed 
throughout the tank and 6.02* 10^23

​ times ​
as much information would be needed to specify where all those carbon 
atoms are, and entropy would have increased.


​ > ​
Now, entropy increase only refers to the increase in the number of
states that have the same macroscopic properties.


​I don't understand your use of the word "only".​

​ > ​
However, if you ask how many different physical states there are
that have the same macroscopic properties as the system in the
final state, then you get a much larger answer


​ Before you burned the diamond only one microstate would produce the 
same macrostate, after the burn a astronomical number would.​




Sure, but it wasn't a closed system.  You added a lot of energy via the 
laser.


Brent

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Re: What day is it?

[Bruce Kellett]

On 25/09/2015 12:53 am, Stathis Papaioannou wrote:
On Wednesday, 23 September 2015, Bruce Kellett 
mailto:bhkell...@optusnet.com.au>> wrote:


On 24/09/2015 4:02 am, Jason Resch wrote:

On Tue, Sep 8, 2015 at 8:45 PM, Bruce Kellett
> wrote:

On 9/09/2015 1:29 pm, Jason Resch wrote:

On Tue, Sep 8, 2015 at 9:44 PM, Bruce Kellett
>
wrote:

I presume you mean that the world is duplicated on each
toss, with one branch showing each outcome. We are back
to the dreaded "person duplication" problem. My opinion
on this is that on such a duplication, two new persons
are created, so the probability that the original person
will see either heads or tails is precisely zero,
because that person no longer exists after the duplication.


So if some aliens create a copy of you in Andromeda, then
you cease to exist as a person?


Since I might know if they gathered the requisite
information, it is not an issue.


I don't see how this follows. Are you saying you would cease to
exist as a person if a duplicate of you arose far away in this
universe, or that you would not cease to exist as a person?


The closest continuer account of personal identity would have no
difficulty with this. The remote "copy" is purely a matter of
chance, which has no physical or causal connection with you, so is
not a continuer in the required sense.


You present "closest continuer theory" as if it is obviously correct, 
and it is not. In any case, even granting the theory, why should the 
causal or physical connection make a difference? I've sometimes 
encountered this claim in these discussions but it is just ad hoc.


The theory is no more ad hoc than any other theory of personal identity. 
When we seek to encapsulate an intuitive notion in language, any attempt 
could be criticized as being ad hoc, so that charge is of no substance.



Note: according to current comological models, space is
infinite and uniform, which means infinite copies of you
exist (though very far away).

Such models make really quite strong assumptions about
initial conditions.


This all follows from thw concordance model of cosmology, which
is the "standard model" in cosmology. See:
http://space.mit.edu/home/tegmark/PDF/multiverse_sciam.pdf

You might well have an infinity of worlds with our present
cosmology, but they might all be copies of some bland, boring
model with no intelligent life.


I don't think you grasp the implications of infinity. If there
are infinite worlds, there is effectively 100% probability that
an infinite number of them will be identical to this entire Earth
as you see it.


As I said, that assumes some regular distribution over initial
conditions --  condition for which we have no evidence whatsoever.
So our universe - and our particular personal existences - might
be unique, even in an infinite universe. There can be universes of
zero probability measure.


The Copernican Principle in conjunction with the observation that the 
universe is uniform in all directions is enough.
No, that is not enough. The Copernician principle is not a law of 
physics -- or of anything else, for that matter. It is a useful 
heuristic, nothing more. The so-called "uniformity of the universe 
(isotropy and homogeneity)" is also nothing more than a useful 
approximation that can be used only on the largest scales -- when you 
average over all local structure. Such arguments have no force against 
the position I am arguing.


You appear not to have grasped the significance of initial conditions. 
The initial conditions of our observed universe are far from generic, 
and all "uniformity" arguments require that initial conditions be 
uniformly generic over the whole infinite extent that is considered.


Bruce


Pi has infinite digits. Any sequence, however long, the encoding
of any documentary, can be found in the digits of Pi, and
moreover, it recurs an infinite number of times.


That, too, is an unproved assumption about uniformity
--essentially the assumption that pi is a normal number. And that
has never been proven.

Bruce



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the incredible proof machine. A graphical logical proof engine

[Alberto G. Corona]

I think that modal logics can be created too:

http://incredible.nomeata.de/

https://www.joachim-breitner.de/blog/682-The_Incredible_Proof_Machine



logic rules can be added:
https://github.com/nomeata/incredible/blob/master/examples/logics/predicate.yaml
-- 
Alberto.

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Re: What day is it?

[John Clark]

On Thu, Sep 24, 2015  Brent Meeker  wrote:

​> ​
> the equations of evolution are time reversible.


​Yes, therefore the reason the second law of thermodynamics exists can't be
in the laws of physics, so it must be in the initial conditions. The
universe must have started out in a very low entropy state.

  John K Clark ​





>

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Re: What day is it?

[John Clark]

On Thu, Sep 24, 2015 at 1:24 PM, smitra  wrote:

>
​> ​
> The entropy is the logarithm of this number of states, more precisely it
> is the amount of information that you would need to specify in order to
> point out in which physical state the system is actually in
>

​Suppose you place a perfect cubic one mole diamond
​in a large tank of oxygen, if you know the weight of the diamond and the
position of just the carbon atom at one corner of the cube then you have
all the information needed to know the position of every atom in the cube
(assuming you know the chemistry of carbon bonds).
Now fire a LASER at the diamond and heat it up till it starts to burn, the
​atoms are no longer in a simple lattice but are distributed throughout the
tank and 6.02* 10^23
​times ​
as much information would be needed to specify where all those carbon atoms
are, and entropy would have increased.


> ​> ​
> Now, entropy increase only refers to the increase in the number of states
> that have the same macroscopic properties.


​I don't understand your use of the word "only".​


> ​> ​
> However, if you ask how many different physical states there are that have
> the same macroscopic properties as the system in the final state, then you
> get a much larger answer


​Before you burned the diamond only one microstate would produce the same
macrostate, after the burn a astronomical number would.​


​ John K Clark​

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Re: The Axiom Of Choice and ComputationalismT

[John Clark]

On Thu, Sep 24, 2015 at  Bruno Marchal  wrote:

​> ​
> You can define prime number in arithmetic,
>

​Who cares? I'm not interested in ​arithmetic or in anything else defining
prime numbers, I'm interested in *CALCULATING *prime numbers.

​> ​
> That the arithmetical reality is independent of the axiom of choice has
> been proved by Gödel
>

Paul Cohen not Godel proved that arithmetical reality is independent of the
Axiom of Choice, Godel just proved it was consistent with it, Cohen proved
its negation was consistent with it too.  And if arithmetical reality is
independent of the axiom of choice then something that was dependent on
BOTH arithmetical reality AND the Axiom of Choice would be different from
just arithmetical reality, maybe something like physical reality.


> ​> ​
> ZF and ZFC see exactly the same arithmetical reality,
>

​In ZFC the ​Banach-Tarski construction is part of reality, in ZF it is
not.  If physics is ZFC then ​Banach-Tarski is physical reality even if
it's not arithmetical reality and physics can do stuff that arithmetic
can't; but we already knew that, arithmetical reality isn't sufficient to
perform calculations.

​>> ​
> Also if the the Axiom Of Choice is true then the Banach-Tarski
> construction (sometimes called paradox) can be done. If you cut up a solid
> sphere and then put all the pieces back together in a way specified by
> Banach and Tarski you can create TWO solid spheres of a size equal to the
> original single sphere. This can’t happen in the real physical world so
> does this fact work against my idea that Physics is arithmetic plus
> the Axiom Of Choice? Maybe not because maybe it does happen in the real
> physical world. We know from astronomical observation that space is
> expanding, new space is being created, and maybe Banach-Tarski is how
> physics does it.



​> ​
> That seems quite speculative
>

​It is, but not as ​
speculative
​ as the idea that the human biological brain ​needs dark matter to operate.

 John K Clark

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Re: The Axiom Of Choice and ComputationalismT

[Bruno Marchal]

On 23 Sep 2015, at 23:59, John Clark wrote:

It seems to me the debate I’v  been having with Bruno, the one  
about Arithmetic being able to perform calculations all by itself  
without the help of matter that obeys the laws of physics, comes  
down to the Axiom Of Choice. I would humbly propose that maybe just  
maybe mathematics is everything EXCEPT for the Axiom of Choice and  
physics is mathematics PLUS​ the Axiom of Choice ​If this is true  
then for something to be really real and not just sorta real physics  
must be able to calculate (choose) it.



The Axiom of Choice says that if you have an infinite number of bins  
with two or more different types of things in them then you can  
always create a new bin containing exactly one item from each bin.  
Bertrand Russell gave this example: “To choose one sock from each  
of infinitely many pairs of socks requires the Axiom of Choice, but  
for shoes the Axiom is not needed.” With shoes you could have a  
finite number of rules (just one in this case)  that would work,  
always pick the left shoe from each bin, but no corresponding finite  
number of rules exists for socks so you’d have to invoke the Axiom  
of Choice. This may have some relevance to the following question:  
If it exceeds the computational power of the entire universe to  
calculate (choose) does the 423rd prime number greater than  
10^100^100 really exist or only sorta exist?


To create a bin containing all the integers the Axiom of Choice is  
not needed, the 8 Zermelo-Fraenkel Axioms are enough; thus you could  
create a bin containing all the integers and only the integers  
{1,2,3,4...} , you can also create bins with {2,3,4,5...} and  
another with {3,4,5,6...} etc. A finite number of rules (just 8) can  
create such bins (sets) . But what about a bin that contains all the  
prime numbers and only the prime numbers?




You don't need the axiom of choice to, prove the existence of the set  
of prime numbers (and only prime numbers).



Without the Axiom of Choice there is no rule of finite length that  
would allow you to choose one and only one prime number from all the  
bins I listed above and use them to come up with a new bin  
containing all the prime numbers and nothing but the prime numbers.


You can define prime number in arithmetic, and PA can prove their  
existence. Everything is even computable. All recursive and  
recursively enumerable set are representable already in the theory of  
finite sets, or the theory of integers, etc.






Godel proved in 1938 that if you assume the Axiom of Choice is true  
then it will cause no contradictions in Zermelo-Fraenkel or in  
arithmetic, and Paul Cohen proved in 1963 that if you assume the the  
Axiom of Choice is false it will cause no contradictions in Zermelo- 
Fraenkel or in arithmetic. In other words the Axiom of Choice is  
independent of arithmetic and independent of the Zermelo-Fraenkel  
Axioms.



No. Independent of ZF.

That the arithmetical reality is independent of the axiom of choice  
has been proved by Gödel using his notion of constructible set. It  
shows that ZF and ZFC see exactly the same arithmetical reality, and  
so the axiom of choice has no role for proving new arithmetical  
theorem. This does not mean that the axiom of choice does not simplify  
the search of such truth, but in principle the use of the axiom of  
choice can be eliminated. That is a different result than the  
independence of AC from ZF (by Gödel and Cohen).







The Axiom of Choice has always been far more controversial than the  
8 Zermelo-Fraenkel Axioms, and mathematicians are reluctant to use  
it in their proofs unless they have to, in fact it’s almost as  
controversial as Euclid’s Fifth Postulate. As I’ve stated it the  
Axiom seems intuitively true, almost bland;




It is not an effective axioms. It is a highly non computational axiom,  
but then the axiom of infinity also. ZF is doin high level theology  
all the times, and has very strong belief.





but the trouble is that you can state the same thing in a different  
way that is absolutely equivalent but when stated that way it seems  
intuitively false. For example, the Axiom of Choice can also be  
stated as "every set can be well ordered” and that seems false;  
“well ordered” means it has a least element, it’s easy to see  
that the set of positive integers is well ordered but how would you  
well order the real numbers? Mathematicians think it’s ugly for the  
Axiom Of Choice to produce a set as if by magic with no instructions  
on how to actually build it.


OK. And Solovay proved that all set of real numbers is measurable, as  
a consequence of the axiom of choice.
We need the choice axiom also to prove the completeness of infinitary  
logics (but I avoid them usually).


Another equivalent version of the Choice axiom is: all linear spaces  
have a base.



Also if the the Axiom Of Choice is true then the Banach-Tarski  
construction (sometimes calle

Re: 1P/3P CONFUSION again and again

[Bruno Marchal]

On 24 Sep 2015, at 01:26, John Clark wrote:


On Mon, Sep 21, 2015  Bruno Marchal  wrote:

​> ​the existence of particular computations and emulations of  
computations by other computations can be proved already in Robinson  
Arithmetic.


​I don't want proof of computations, I want computations!​



If you prove the existence of something in something else, you have  
that something, in that something else.


If you want a physical computation, you need only to pray that a  
physical reality exist, and rich enough to be Turing complete, as it  
*looks* to be the case, and then you can build a computer, which can  
run physical computations. but that does not make the many non  
physical computation to continue to exist in arithmetic, and indeed a  
universal machine cannot distinguihs a physical computation from a non  
physical one, from its experience only: it needs to do 3p measurements.







​>​There is a continuous and a diecrete quantum teleportation  
technic


​I don't know what that means. But I do know that Quantum Mechanics  
can't ​deal with distances smaller than 1.6*10^-35 meters; if  
distances smaller than that exist then Quantum Mechanics will need a  
MAJOR overhaul.


​>>​​I'm just playing ​devil's advocate​,​​ ​​​ 
unlike you I don't claim to have proven anything​.​


​> ​Proving is my job. That is what I do. That is what  
mathematician does, in math or in applied theoretical field. When I  
say that RA proves the existence of the terminating computations, I  
am saying a standrd result.


​Very standard indeed! Every mathematician knows that some  
computations terminate, and some computations don't terminate, and  
for some computations there is no way to know if they terminate or  
not and all you can do is watch it and see. ​


Exactly, but that makes my point. Each time a computation terminates,  
RA can prove that facts; like the universal dovetailer can run on all  
terminating computations, although it has to dovetail on all  
computations, terminating or not, to get all the terminating one.









​> ​You oppose this by introducing a notion of physical  
computation, which you have not yet define.


​I can provide something​ ​much much better than a definition,  
I can give A EXAMPLE.


I gave you an example of an immaterial computation too.




 ​
​> ​even if physics is quite important. the fundamental science  
is theoretical computer science


​I do admit that sometimes physics papers about entropy and Black  
Holes look a lot like papers in computer science or information  
theory.


OK, and I think that computationalism suggest explanations for this  
since a long time.


Bruno





 John K Clark ​





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http://iridia.ulb.ac.be/~marchal/



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Re: What day is it?

[smitra]

Thermodynamic entropy requires a coarse graining procedure to be 
specified to define it rigorously. Given a physical system, you decide 
to describe it in terms of only a few macroscopic variables. So, only a 
few bits of information are specified, which means that there are an 
astronomically large number of physical states that are compatible with 
it.


The entropy is the logarithm of this number of states, more precisely it 
is the amount of information that you would need to specify in order to 
point out in which physical state the system is actually in (they don't 
need to be equally probably, so in general you need to use the Shannon 
entropy formula).


Now, entropy increase only refers to the increase in the number of 
states that have the same macroscopic properties. E.g. if you do a free 
expansion experiment and assume that the system is completely isolated, 
then if the system is known to be in one out of Omega states, then after 
the free expansion into the larger volume it can only be in one out of 
Omega final states.


However, if you ask how many different physical states there are that 
have the same macroscopic properties as the system in the final state, 
then you get a much larger answer (if the volume doubles then it will 
have increased by a factor of 2^N where N is the number of particles in 
the system).


This larger number of possible states are not the states the system can 
actually be in, they just look the same after you perform a course 
graining to extract its macroscopic properties.  E.g. under a time 
reversal, almost none of them will evolve back to the smaller volume.


But then if you are given such a perfectly isolated system with that 
larger volume and you don't know about its history; for all you know, it 
could be in one of these larger number of states. Also the moment it 
interacts with the environment, that causes perturbations and all these 
larger number of states will be in play.


Saibal






On 24-09-2015 18:15, John Clark wrote:

On Thu, Sep 24, 2015  smitra  wrote:


​> ​The laws of physics forbid creating information out of
nothing


​If that were true then entropy would be conserved, but the second
law​
​of thermodynamics insists that it is not and always increases.​
Some physicists have tried to use entanglement and some fancy footwork
to get around this problem but I don't find it very convincing.

  John K Clark

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Re: What day is it?

[Brent Meeker]

On 9/24/2015 9:15 AM, John Clark wrote:
On Thu, Sep 24, 2015  smitra >wrote:


​ > ​
The laws of physics forbid creating information out of nothing 



​ If that were true then entropy would be conserved, but the second law​
​ of thermodynamics insists that it is not and always increases.​


The definition of an entropy and it's increase depends on averaging and 
coarse graining.  At the microscopic, fundamental level there is no 
increasing entropy; the equations of evolution are time reversible.


Brent

Some physicists have tried to use entanglement and some fancy footwork 
to get around this problem but I don't find it very convincing.


  John K Clark



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Re: What day is it?

[Bruno Marchal]

On 23 Sep 2015, at 17:45, smitra wrote:


On 16-09-2015 16:24, Bruno Marchal wrote:

On 15 Sep 2015, at 22:33, smitra wrote:

On 12-09-2015 10:26, Bruno Marchal wrote:

On 11 Sep 2015, at 18:17, smitra wrote:
It seems to me that COMP should lead to MWI plus a preferred   
basis  where the latter derives from well defined computational   
states.  Many of the problems with the MWI should not arise  
here,  they are an  artifact of the theory never defining what  
an  observation is,  appealing to ad hoc intuitive notions that  
are  never formulated from  within the theory itself.
The notion that the environment plays a fundamental role should   
be  rejected on physical grounds, it just explains the  
effective  physics  we observe just like air resistance explains  
why Newton's  laws were  not all that obvious to people who  
lived many centuries  ago.
The only way you can explain Newton's law to students is by   
letting  them contemplate a perfect vacuum. It doesn't matter  
here  how  physically unrealistic that perfect vacuum is or  
isn't. The  same is  true for quantum mechanics. You'll never  
make process if  you always  invoke the environment and  
environment induced  decoherence to try to  define fundamental  
concepts, because Nature  cannot possibly work  that way on the  
fundamental level.
Instead, within quantum mechanics (i.e. if we forget about the
desire to derive QM from COMP or some other deeper theory)   
defining  observers as computations,  means that they should be   
represented as  operators of the form:

sum over input of |output>which leads to a preferred basis when you introduce an  
environment.

An environment or a universal machine, with or without oracle(s).
I think we agree.
I hope you agree that we agree here.
Yes, and I think you could make a lot of progress by trying to   
deconstruct QM in terms of algorithms.

Algorithm cannot be enough.
Assuming Mechanism, the doctrine that there is a physical universe is
deconstructed, and with Church thesis, the deconstruction is  
partially

constructive, as it shows what physics has to be given by the global
FPI calculus on the computations/sigma_1 sentences.
But the FPI calculus does not rely exclusively  on the computations
(modeled by the true sigma_1 sentences), but on the logic of correct
self-reference with respect to those propositions, or logic of
provability (and its intensional variants) with the atomic
propositions being the sigma_1 arithmetical sentences. Despite
provability, unlike computability,  is a relative notion, depending  
on

the machine or subject, as long as it is supportable by a machine,
and  arithmetically correct, the general laws of self-reference
(captured  by G*) will apply, and physics depends only on that.
And so I think that the work is entirely done, at least at the
propositional level. QM proposition calculus is entirely given by the
logics of []p & <>t (& p). The FPI is not algorithmic, even if the
distribution of probability is algorithmic with the simple protocol,
but even the simple FPI is no more algorithmic on the universal
dovetailing (or on the sigma_1 propositions) as we cannot recognize
them as such algorithmically. This makers very nice that the
propositional logic of observable is decidable (and close to a  
Quantum

Logic).
Note that the quanta appears at the star-level (in X1* minus X1),
making quanta into special case of qualia, which is coherent with
Everett's superposition of collection of people (first person plural)
and with the idea that the "absolute 3p reality is a multi-dreams  
(and

note a many-worlds). This shows that even with the Everett "MWI", we
don't have any world: only sharable first person experiences. If the
quanta would have appeared in Z1 or X1 (and not in the proper star-
extension) a notion of apparent global physical reality would have
made sense, but it looks we lost this.
I recall the 8 povs or "hypostases";
1) p   (truth of p)
2) [0]p = []p = bewesibar('p'), with p a (sigma_1) arithmetical   
sentence.

3) [1]p = []p & p  (the knower, or soul or inner god)
4) [2]p = []p & <>t (the observer, gambler, ...)
5) [3]p = [2]p & p  (the "senser").
which can be put in this diagram:
  1=1*
22*
  3=3*
44*
55*
We have that
  1=1*
22*
  3=3*
is the basic propositional theory of mind/soul  (1= One, 2 =
Intellect, 3 = Soul)
and
44*
55*
gives the "two sorts of matter": 4 = intelligible matter, 5 =  
sensible  matter.

Quantizations appear at 3*, 4*, and 5*. That suggests 3 sorts of
logics structuring (slightly?) differently the physical reality. I
guess that 3* is "heaven physics" (the physics of the soul which has
not yet felt), and 4*, like 5*, are the physics of "earth", when we
sin in the bet on the non justifiable "Reality" (<>t).
So we can not only test mechanism, but we can test if we are in  
heaven

or not :)
No need to take this too much seriously. A lot of research needs to
be pursued to clarify all t

Re: What day is it?

[Bruno Marchal]

On 24 Sep 2015, at 02:30, Jason Resch wrote:




On Wed, Sep 23, 2015 at 4:20 PM, Bruce Kellett > wrote:

On 24/09/2015 4:02 am, Jason Resch wrote:


On Tue, Sep 8, 2015 at 8:45 PM, Bruce Kellett > wrote:

On 9/09/2015 1:29 pm, Jason Resch wrote:


On Tue, Sep 8, 2015 at 9:44 PM, Bruce Kellett > wrote:
I presume you mean that the world is duplicated on each toss, with  
one branch showing each outcome. We are back to the dreaded  
"person duplication" problem. My opinion on this is that on such a  
duplication, two new persons are created, so the probability that  
the original person will see either heads or tails is precisely  
zero, because that person no longer exists after the duplication.


So if some aliens create a copy of you in Andromeda, then you  
cease to exist as a person?


Since I might know if they gathered the requisite information, it  
is not an issue.


I don't see how this follows. Are you saying you would cease to  
exist as a person if a duplicate of you arose far away in this  
universe, or that you would not cease to exist as a person?


The closest continuer account of personal identity would have no  
difficulty with this.


It might not, but closest continuer theory makes no sense and  
appears to be an ad hoc way to escape what otherwise clear  
conclusions from non-dualist theories of mind.


If you run an identical computer program on a different computer,  
one on mars and one on the moon, why say the one on the moon the  
only one that is identical to the program last run on Earth?


What if the two copies are an identical number of Plank lengths  
away? Or what if many are all run on a sphere whose center is where  
the last instance ran?


Closest continuer theory has no theoretical justification. The only  
reason it even exists is that some find the idea that they are not  
unique to be too upsetting. Closet continuer theory purports to  
offer a way to guarantee uniqueness of the individual (at least  
until you consider ties by equally close continuations).


That is the case with computationalism, and even computationalism +  
Oracles.


But if Bruce decide to say no to *all* possible doctors, or that he is  
an actually infinite machinery, then I can imagine some closer  
continuer theiry to make sense, although it does not exist yet.


Of course, that can be considered as an ad hoc move to escape the non- 
uniqueness of oneself.









The remote "copy" is purely a matter of chance, which has no  
physical or causal connection with you, so is not a continuer in the  
required sense.


Note: according to current comological models, space is infinite  
and uniform, which means infinite copies of you exist (though very  
far away).
Such models make really quite strong assumptions about initial  
conditions.


This all follows from thw concordance model of cosmology, which is  
the "standard model" in cosmology. See:

http://space.mit.edu/home/tegmark/PDF/multiverse_sciam.pdf


You might well have an infinity of worlds with our present  
cosmology, but they might all be copies of some bland, boring model  
with no intelligent life.


I don't think you grasp the implications of infinity. If there are  
infinite worlds, there is effectively 100% probability that an  
infinite number of them will be identical to this entire Earth as  
you see it.


As I said, that assumes some regular distribution over initial  
conditions --  condition for which we have no evidence whatsoever.


All current observations are consistent with the uniformity of the  
universe. At large scales the universe is very homogenous, and it is  
believed that early quantum fluctuations (which are effectively  
random) shaped the clumping of matter.



Assuming mechanism makes this possible, but not necessarily relevant,  
as, assuming mechanism, we belong to infinities of "universes/ 
histories" of all sizes, anyway.







So our universe - and our particular personal existences - might be  
unique, even in an infinite universe. There can be universes of zero  
probability measure.


Pi has infinite digits. Any sequence, however long, the encoding of  
any documentary, can be found in the digits of Pi, and moreover, it  
recurs an infinite number of times.


That, too, is an unproved assumption about uniformity --essentially  
the assumption that pi is a normal number. And that has never been  
proven.



It doesn't have to be normal, it just has to be irrational (no  
repeating pattern) which is proven. In any event, I was just using  
Pi to illustrate that when there is an infinite extension (without a  
trivial repetition) the same sequences will recur. You need to adopt  
non-standard cosmological theories to say this implication does not  
apply in the case for our universe.


To avoid the lack of proof of normality of Pi, you can use  
Champernowne number (in base 10), which is provably normal, trivially  
irrational, and as been proved transcendental (by Champernowne 1933,  
Bailey and C

Re: What day is it?

[John Clark]

On Thu, Sep 24, 2015  smitra  wrote:

​> ​
> The laws of physics forbid creating information out of nothing


​If that were true then entropy would be conserved, but the second law​

​of thermodynamics insists that it is not and always increases.​ Some
physicists have tried to use entanglement and some fancy footwork to get
around this problem but I don't find it very convincing.

  John K Clark

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Re: A scary theory about IS

[Bruno Marchal]

On 23 Sep 2015, at 21:24, Brent Meeker wrote:




On 9/23/2015 3:15 AM, Bruno Marchal wrote:


On 22 Sep 2015, at 23:55, John Mikes wrote:

Bruno, I am at a loss with your explanation. I lived the active  
first 50 years of my life in Europe and never heard about such  
'liberalism' (for a short time was even connected to the Hungarian  
Liberal Democratic Party).


In my counntry the right party has the name "parti libéral", for  
example. Liberal means "open to free markets".

May be that is only in West Europa.


"Liberal" was in no connection with right/wrong, or even right/ 
left, only pointed to some freedom of action in the political  
arena. And the other thing:


Democracy IMO is an oxymoron, the full "demos" cannot exercise  
it's full "cratos" for ruling,



Democracy means, for me, presence of election. It can be partial,  
like in the beginning where woman did not have the right to vote,  
or like in the antic greece were election was for the educated  
class, and not for slaves, or it is "universal", meaning everyone  
can vote. In some country it is "everyone *must* vote (in Belgium  
election are obligatory).


Then a democracy can be corrupted, and/or under the influence of  
corporatism, and/or sick etc. Democracy is not the final state of  
politics, it is the prerequisite of having a representative  
politics. If the main powers (mainly justice and press) are not  
independent, a democracy can be de facto a tyranny disguised into  
democracy. I think that is the case today (since prohibition).


It is the like the Islamic bill or right, which is a copy of the  
universal definition except that they have added "as long as it  
verifies the Charia" for each principle (which of course changes  
the very idea). The same with Obama who signed a text which respect  
the human right except for a category or people, but something have  
to be universal to make sense. The human right applies to all  
humans, or there is no more human right at all.




Democracy is necessary but not sufficient for good government.


I agree.


Supposing that democracy is enough was the mistake of George W. Bush  
and the neo-conservatives.


That mistake, but also the mistake that we can impose democracy to  
others, or the even more naïve idea that by eliminating a dictator  
will make people opting for a democracy.


A democracy needs a lot of generation of thinking people.

And just one generation of people can make it disappear, or weakened  
so much that it "stays" as a democracy only for a part of the  
population.





 They thought that if we just held elections in Iraq all would be  
well.  But there must be limitations on government, constitutional  
restraints and traditional restraints.  Otherwise whomever has the  
majority assumes that democracy means they can oppress the minority.


The case of Egypt is quite remarkable in that respect. They made a  
successful revolution to set back a military dictatorship. They  
succeeded in making a democracy, that is, organizing election. They  
vote for the Muslim Brotherhood, and when they realized the Muslim  
Brotherhood was killing the democracy and imposing a religious  
dictatorship, the people made a second revolution to re-install the  
military dictatorship, and even to fight the Muslim Brotherhood  
(courtized and encouraged by Obama, by the way). They have understood  
that a secular military dictatorship is far better than a religious  
dictatorship. Somehow, they understood they were not ready for  
democracy. too much people still believe that they know the truth and  
impose it to others.
That was a bit of a relief, and it is sad this occurred only in Egypt  
although in Tunisia some bit of reason to hope remains.












becuase every person has different aims, goals, interests, etc.  
Those, who call a "majority-rule" a democracy are establishing a  
minority whose interests are trampled down by the so called  
"majority" which is not even so sure, to BE a majority indeed.  
Voting is cheating, candidates LIE in the campaign and the voters  
compromise their (real?) interests for the least controversial  
lies. What is even worse: the "elected" persons don't even follow  
their own lies later on in practice. They go after their  
(untold???) interest. Impeachment is difficult.


Yes, but that is because our democracies are sick. It is not  
because a car is broken that a car is not supposed to be driven.


And I wish the minority having no power, but a problem with more  
than two parties is that the minority can have tremendous infuence.  
Indeed the minority will often makes the difference when the  
majorities disagree. But the french Condorcet has already studied  
the impossibility of satisfying everybody by a voting procedure,  
and democracies can evolve, and we can change the rules, ... unless  
the system has been corrupted.


It is not because we can die of cancer that we are not alive. It is  
the same with democracy, they ca

Re: What day is it?

[smitra]

There actually is a physical connection. You have to ask how that 
duplicate could arise there. Where does the information come from? The 
laws of physics forbid creating information out of nothing and they 
local in nature, so the information must have come from its local 
neighborhood. You can contemplate duplication experiments where you sent 
the information there, or there was a copy of you there all along that 
was evolving in the same was as you, in which case you were present 
there all along, or at least physically you could not have distinguished 
between the two slightly different locations.


Even if you invoke exotic processes like somehow a Boltzmann brain 
fluctuating out of the vacuum,  this is not going to allow you to 
distinguish the "exotic location" from the "non-exotic" one, because 
from your perspective everything is symmetric. While one may have larger 
probability, it's not true that a priori you are either here or there.


Saibal


On 24-09-2015 16:53, Stathis Papaioannou wrote:

On Wednesday, 23 September 2015, Bruce Kellett
 wrote:


On 24/09/2015 4:02 am, Jason Resch wrote:

On Tue, Sep 8, 2015 at 8:45 PM, Bruce Kellett
 wrote:

On 9/09/2015 1:29 pm, Jason Resch wrote:

On Tue, Sep 8, 2015 at 9:44 PM, Bruce Kellett
 wrote:

I presume you mean that the world is duplicated on each toss, with
one branch showing each outcome. We are back to the dreaded "person
duplication" problem. My opinion on this is that on such a
duplication, two new persons are created, so the probability that
the original person will see either heads or tails is precisely
zero, because that person no longer exists after the duplication.

So if some aliens create a copy of you in Andromeda, then you cease
to exist as a person?


 Since I might know if they gathered the requisite information, it is
not an issue.

I don't see how this follows. Are you saying you would cease to exist
as a person if a duplicate of you arose far away in this universe, or
that you would not cease to exist as a person?
 The closest continuer account of personal identity would have no
difficulty with this. The remote "copy" is purely a matter of chance,
which has no physical or causal connection with you, so is not a
continuer in the required sense.

You present "closest continuer theory" as if it is obviously correct,
and it is not. In any case, even granting the theory, why should the
causal or physical connection make a difference? I've sometimes
encountered this claim in these discussions but it is just ad hoc.


Note: according to current comological models, space is infinite and
uniform, which means infinite copies of you exist (though very far
away). Such models make really quite strong assumptions about
initial conditions.


This all follows from thw concordance model of cosmology, which is the
"standard model" in cosmology. See:
http://space.mit.edu/home/tegmark/PDF/multiverse_sciam.pdf [3]


You might well have an infinity of worlds with our present
cosmology, but they might all be copies of some bland, boring model
with no intelligent life.


I don't think you grasp the implications of infinity. If there are
infinite worlds, there is effectively 100% probability that an
infinite number of them will be identical to this entire Earth as you
see it.
 As I said, that assumes some regular distribution over initial
conditions --  condition for which we have no evidence whatsoever. So
our universe - and our particular personal existences - might be
unique, even in an infinite universe. There can be universes of zero
probability measure.

The Copernican Principle in conjunction with the observation that the
universe is uniform in all directions is enough.


Pi has infinite digits. Any sequence, however long, the encoding
of any documentary, can be found in the digits of Pi, and
moreover, it recurs an infinite number of times.


That, too, is an unproved assumption about uniformity --essentially
the assumption that pi is a normal number. And that has never been
proven.

Bruce


I think you are trying to avoid answering my question.

Jason



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Re: Mandela effect?

[Bruno Marchal]

On 23 Sep 2015, at 21:05, Brent Meeker wrote:


Never heard of it before.

http://www.skeptic.com/insight/the-mandela-effect/



I agree with the conclusion of the paper. Also, if that "mandela-many- 
world" theory was correct, it would mean that parallel universes can  
interact, and that QM is non linear (and the SWE only an  
approximation), and that would mean that basically all basic physical  
principles are false (GR and thermodynamic are refutable in such a  
theory, as shown by Plaga and Weinberg).


Bruno




Brent

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http://iridia.ulb.ac.be/~marchal/



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Re: What day is it?

[Stathis Papaioannou]

On Wednesday, 23 September 2015, Bruce Kellett 
wrote:

> On 24/09/2015 4:02 am, Jason Resch wrote:
>
>
> On Tue, Sep 8, 2015 at 8:45 PM, Bruce Kellett  > wrote:
>
>> On 9/09/2015 1:29 pm, Jason Resch wrote:
>>
>> On Tue, Sep 8, 2015 at 9:44 PM, Bruce Kellett > > wrote:
>>
>>> I presume you mean that the world is duplicated on each toss, with one
>>> branch showing each outcome. We are back to the dreaded "person
>>> duplication" problem. My opinion on this is that on such a duplication, two
>>> new persons are created, so the probability that the original person will
>>> see either heads or tails is precisely zero, because that person no longer
>>> exists after the duplication.
>>>
>>
>> So if some aliens create a copy of you in Andromeda, then you cease to
>> exist as a person?
>>
>>
>> Since I might know if they gathered the requisite information, it is not
>> an issue.
>>
>
> I don't see how this follows. Are you saying you would cease to exist as a
> person if a duplicate of you arose far away in this universe, or that you
> would not cease to exist as a person?
>
>
> The closest continuer account of personal identity would have no
> difficulty with this. The remote "copy" is purely a matter of chance, which
> has no physical or causal connection with you, so is not a continuer in the
> required sense.
>

You present "closest continuer theory" as if it is obviously correct, and
it is not. In any case, even granting the theory, why should the causal or
physical connection make a difference? I've sometimes encountered this
claim in these discussions but it is just ad hoc.

> Note: according to current comological models, space is infinite and
>> uniform, which means infinite copies of you exist (though very far away).
>>
>> Such models make really quite strong assumptions about initial conditions.
>>
>
> This all follows from thw concordance model of cosmology, which is the
> "standard model" in cosmology. See:
> http://space.mit.edu/home/tegmark/PDF/multiverse_sciam.pdf
>
>
>
>> You might well have an infinity of worlds with our present cosmology, but
>> they might all be copies of some bland, boring model with no intelligent
>> life.
>>
>
> I don't think you grasp the implications of infinity. If there are
> infinite worlds, there is effectively 100% probability that an infinite
> number of them will be identical to this entire Earth as you see it.
>
>
> As I said, that assumes some regular distribution over initial conditions
> --  condition for which we have no evidence whatsoever. So our universe -
> and our particular personal existences - might be unique, even in an
> infinite universe. There can be universes of zero probability measure.
>

The Copernican Principle in conjunction with the observation that the
universe is uniform in all directions is enough.

> Pi has infinite digits. Any sequence, however long, the encoding of any
> documentary, can be found in the digits of Pi, and moreover, it recurs an
> infinite number of times.
>
>
> That, too, is an unproved assumption about uniformity --essentially the
> assumption that pi is a normal number. And that has never been proven.
>
> Bruce
>
>
> I think you are trying to avoid answering my question.
>
> Jason
>
>



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Re: Undecidability of the Spectral Gap

[Bruno Marchal]

On 23 Sep 2015, at 23:42, Brent Meeker wrote:




On 9/23/2015 12:19 PM, Bruno Marchal wrote:


On 23 Sep 2015, at 06:51, Brent Meeker wrote:




On 9/22/2015 9:26 PM, Bruno Marchal wrote:


On 22 Sep 2015, at 19:27, Brent Meeker wrote:




On 9/22/2015 5:17 AM, Bruno Marchal wrote:


On 22 Sep 2015, at 00:29, Brent Meeker wrote:


A fascinating application of computability theory to physics:

Undecidability of the Spectral Gap
Toby Cubitt,  David Perez-Garcia,  and Michael M. Wolf

The spectral gap—the difference in energy between the ground  
state and the first excited state—is one of the most important  
prop-
erties of a quantum many-body system. Quantum phase  
transitions occur when the spectral gap vanishes and the  
system becomes
critical. Much of physicsis concerned with understanding the  
phase diagrams of quantum systems, and some of the most  
challenging
and long-standing open problems in theoretical physics concern  
the spectral gap, 1–3 such as the Haldane conjecture 4 that  
the Heisen-
berg chain is gapped for integer spin, proving existence of a  
gapped topological spin liquid phase, 2,3 or the Yang-Mills  
gap conjecture 5
(one of the Millennium Prize problems). These problems are all  
particular cases of the general spectral gap problem: Given a  
quan-
tum many-body Hamiltonian, is the system it describes gapped  
or gapless? Here we show that this problem is undecidable, in  
the
same sense as the Halting Problem was proven to be undecidable  
by Turing.


I guess he means unsolvable.

"undecidable" is relative to a theory. Unsolvable or  
uncomputable is absolute and does not depend on any theory. It  
means that there is no alogorithm to do some task, like  
computing some function or deciding some set.


Yes, and it would be quite surprising to find there is no  
algorithm to compute whether or not a Hamiltonian system has a  
mass gap - since it is presumably a fact of nature whether it does  
or not.


Not sure that this entails the existence of an algorithm. In the  
arithmetical reality, many facts exists with provably no algorithm  
to decide them.


But many scientists implicitly assume that reality is computable,


But this is ambiguous. From outside the universe compute the empty  
function, so it is computable by the algorithm "do-nothing".


Computable applies to "function from N to N ore recursively  
equivalent)" (which might be characteristic function of a set, so we  
can extend the notion of computability to set belongness, and if the  
set is a set of theorem, semi-decidable will correspond to *partial*  
computability).


An expression like "reality is computable" does not make sense a  
priori, as "reality" is a term impossible to define from inside a  
theory or system.




that there is an algorithm for deciding how the state of the  
universe evolves.



OK, in that sense, it is better to use the term emulable or simulable,  
which can be applied to processes (and be well defined using the  
intensional Church thesis). This is directly refuted by  
computationalism if we define reality by what we can observe (which is  
1p and typically non computable), but would be computable, and look  
computable (in that "emulable sense) if current physics is exact.


Of course with comp, the notion of "physical universe" is quite  
different than from what we usually understand by such terms. The  
physical universe is a first person sharable history. There is no  
physical universe per se; only numbers coherent dreams.


All known *processes" in Nature are Turing-emulable. But that does not  
yet entails that derivative of known processes are computable. Specker  
showed that there are computable function with a derivative which is  
not computable (from R to R, a notion which does not really have a  
Church thesis, but there is a more or less standard definition given  
by Turing). Now, such weird function have not been encountered in  
nature, but computationalism leads to the idea that some observation  
are not predictible, but then it might just be the outcome of a self- 
superposition or self-duplication.





 And so they reject the idea that reality is isomorphic to arithmetic.


Which reality? With computationalism, we can take as "fundamental  
reality" the tiny sigma_1 part of arithmetic. This gives a set which  
is already not computable, but it is partial computable, and we can  
recursively enumerate the *true* sigma_1 sentences (but already not  
the false one, or we could decide the halting problem). Now the full  
(first order) arithmetic is far bigger than this, and most  
arithmetical proposition are undecidable in al all first order theories.


Then, having that simple (but only partially computable ontology), the  
physical reality is necessarily not computable and much more complex,  
although than we can bound the complexity by the level of  
unsolvability of qG*: it PI_1 complete in the oracle for arithmetical  
truth. If God is arithmetica