Observer Moment = Sigma1-Sentences

From: Bruno Marchal <>
Date: Mon, 30 Jul 2007 11:47:48 +0200

Le 27-juil.-07, à 16:54, David Nyman a écrit :

> On 27/07/07, Bruno Marchal <> wrote:
>> What are your knowledge of quantum mechanics?
> Not very deep - only what I've gleaned in a largely non-mathematical
> way from incessantly reading and musing about the topic for years.
> But I think I'm sufficiently orientated in the basic ideas and
> alternative interpretations to have a chance at following up at least
> some specific topics, that you might suggest, in more detail. But
> this can wait if you feel it's premature.

It can wait, and from a purely logical point of view it is necessary
only at the last step when we will compare the comp-physics and the
empirical physics. Meanwhile I would suggest you read the book by David
Albert: "Quantum Mechanics and Experience"
That book even reminds you the elementary linear algebra, and it gives
the keys for serious study of the conceptual problems. You will not
been able to solve any physical (implementations) problems, but you
will be able to understand the conceptual issues of quantum
information/computing science, which are all we need.

>> The empirical
>> test consists in comparing those multiverse strurctures atatched to
>> entitiess-points of view and what we observe ... indirectly
>> (observation is always indirect, ok?).
> Definitely OK. Perhaps an example of a specific comparison of this
> kind would be a good starting point?

I can compare only the "logic of probability/credibility one" of nature
(more or less quantum logic) and the logic of "probability/credibility
one" extracts from the discourse of the self-observing machine. It *is*
technical. It cannot be a starting point, I think.
In my opinion, the starting point is Church thesis. Once you are back,
tell me and I can do that.

> The following may not be
> relevant in this context, but I'm particularly interested in something
> you said elsewhere ('simulation argument') about how comp can relate
> OMs (and presumably the multiverse structures associated with them)
> geometrically 'through time'.

If this is not relevant in this context, I ask what is relevant ... ?
The problem you mention is at the cross of my work and the everything
list. Now, as I said some days ago, I think that a way to link more
formally my work and the everything discussion can consist in defining
a notion of basic atomic third person observer moment. The UDA, plus
Church thesis + a theorem proved in Boolos and Jeffrey (but see also
and better perhaps just Franzen's appendix A) makes it possible to
define the comp third person OMs by the Sigma1 sentences of
arithmetical language. Those have the shape ExF(x) with F(x) decidable.
For example ExPrime(x) (a prime number exists), Ex(x = code of
triple(a,b,c) and machine a gives c on argument b), ... This last
example show that the notion of Sigma1 sentences is rather rich and
encompasses full computability. So the very restricted notion of
Sigma1-proof (restricted from the point of view of provability) is
already absolutely universal with respect to computability. A machine
is universal iff the machine is Sigma1 complete, i.e. is capable of
proving all true Sigma1 sentences. Such a machine codes automatically
a Universal Dovetailer: to be a UD accessible state is Sigma1.
So the measure we are searching can be put on the set of Sigma1
sentences. Intuitively, from UDA, the weight for each Sigma1 sentences
should be given by the "number" of proof going trough those sentences
(including the many infinite proofs of some false sigma1 sentences).
Now we can search for some equivalence relation on those proofs, but
this is known to be very hard, and that is why I prefer to interview
the universal lobian machine directly, and content myself with the
corresponding logic of "certainty".

> Is this is an area where comp
> consequently can recover 'dynamically experienced' observer histories
> within a block or static context more satisfactorily than e.g. the
> Deutsch 'disconnected slice' view as propounded in FOR?

Yes and No.
Yes for two reasons: 1) if we assume comp, the UDA shows we have to
recover knowledge from infinities of computations in the UD* (the
"block" universal dovetailing. And FOR does presuppose comp. 2) in the
arithmetization of the UDA, the notion of knowledge coherent with the
UD thought experience is just given by the older definition of
knowledge as true justified opinion (in platonism, but also in a lot of
east and west rational account of mystical experiences). It is a gift
that we arrive formally here at temporal-like logic of evolving first
person knowledge.
No, because today, obviously, the quantum hyp is much more efficacious
than the comp hyp (except that this really comes from Everett, which is
SWE-without-collapse+comp, and the UDA shows that comp has to justify
the SWE. Comp shows Everett as incomplete, if (probably) correct).

>> Yes. You can implore, cajole or simply ask. (I'm a bit less sure for
>> the wheedling given that I don't know what that means!).
> wheedle
> -verb (used with object)
> 1. to endeavor to influence (a person) by smooth, flattering, or
> beguiling words or acts: We wheedled him incessantly, but he would not
> consent.
> 2. to persuade (a person) by such words or acts: She wheedled him
> into
> going with her.
> 3. to obtain (something) by artful persuasions: I wheedled a new
> car
> out of my father.
> -verb (used without object)
> 4. to use beguiling or artful persuasions: I always wheedle if I
> really need something.
> [Origin: 1655-65; orig. uncert.]

Thanks. So you can wheedle too, although I'm not sure this is strictly
necessary, cajoling is enough :)


> David wrote:
>> Le 27-juil.-07, à 13:31, David Nyman a écrit :
>>> How will I ever know? I suppose I'm asking: what specifically are
>>> the
>>> critical tests?
>> See my answer to Tom. A specific test would be to test some Bell
>> inequality in the comp phys. To say more I have to be more technic,
>> and
>> I am not sure this is not a bit premature. Let me think ... Not all
>> attempt to explain this in the past (of the list) has been successful,
>> so I have to work the technics.
>> What are your knowledge of quantum mechanics? Have you study some
>> quantum algorithm, Deutsch problem, counterfactual quantum
>> computations. You know, to ANY points of view (first, second, third,
>> ..., of machines, angels, Gods,) you can associate formally some
>> multiverse structures. As you know, observation has lead to expect
>> those multiverse to exist in some more palatable ways. The empirical
>> test consists in comparing those multiverse strurctures atatched to
>> entitiess-points of view and what we observe ... indirectly
>> (observation is always indirect, ok?).
>>> Either way, could I
>>> implore, cajole, wheedle, or simply ask (but never force) you to
>>> explain the main thrust in English with as few preconceptions as
>>> possible?
>> Yes. You can implore, cajole or simply ask. (I'm a bit less sure for
>> the wheedling given that I don't know what that means!).
>> As for the preconceptions, *you* have to say the relevant "Why?" and
>> "How so?" in the relevant places ...
>> I will try asap.
>> Best,
>> Bruno
> >

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Received on Mon Jul 30 2007 - 05:48:05 PDT

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