Stephen P. King (stephenk1@home.com)
Sun, 12 Sep 1999 12:45:51 -0400
Dear Matti,
Matti Pitkanen wrote:
>
> Dear Matti,
>
> Matti Pitkanen wrote:
> [SPK]
> > John Baez explains well my problem with QFT and symmetries!
> >
> > In article <sNluueA1XM03Ewgw@upthorpe.demon.co.uk>,
> > Oz <Oz@upthorpe.demon.co.uk> wrote:
> > >In article <7qpnl4$78f@charity.ucr.edu>, John Baez
> > ><baez@galaxy.ucr.edu> writes
> >
> > >>(Personally I suspect that the whole idea of spacetime as
> > >>a manifold breaks down at this point, but we really know
> > >>rather little about these things - though we calculate
> > >>endlessly and publish lots of papers.)
> >
> > [MP] I express point of view immediately. What breaks down, according
> > to my belief, is the approximate identity of psychological and
> > geometric
> > time in time scale of order 10^4 Planck lenghts. Psychological time
> > is discrete (the center of mass temporal coordinate of cognitive
> > spacetime sheet increases the average amount by about 10^4 Planck times
> > in quantum jump). No revolutions in understanding of geometric time:
> > Riemann did something rather final!
>
> [SPK]
> I see that you could understand what I has thinking right away! :-) But, you
> are a minority in not seeing a problem with the concept of "geometric
> time"! One problem I have is how do you model the communication between
> two observers, do you propose wormholes connecting their "cognitive
> space-time sheets". I am having trouble translating your fixed geometry
> ideas over to my "every thing is process" way of thinking...
>
> [MP] Spacetime is not fixed: every 10^4 Planck times it is
> replaced with a quantum superposition of new ones!
This, to me, implies the a priori existence of an equivalence class of
space-times! This is conceptually equivalent to a spinoral configuration
space if we assume a spinor type relation to exist between any pair of
space-times in the equivalence class...
My main thought is that while the "existence" of space-times is real,
we are seriously mistaken when we assume that a "space-time" has any
meaning outside of the realm of observation. We observe objects that
have metrical relations with each other, but the particular metrical
relations can not be said to be "objective" in that they would have
particular meanings , they are only meaningful within to observers. They
are an aspect of experience. Even Spinoza recognized this, but his
theistic leanings lead him to assume that "God" was the observer that
gave them meaning. We can not have such metaphysical "obscurum per
occultum" notions at the foundations of a model that is supposed to be
falsifiable!
> Information transfer occurs certainly via wormholes since
> they mean physical contact. "Ontogeny recapitulates.." suggests
> the following that the following rules are OK.
But this is were I come to a grinding stop in my understanding of your
thinking! If two observers that are communicating is modelable as a pair
of space-time sheets that are connected by wormholes, there would be a
certain cohomology algebra definable over the whole. This is talking
about the algebraic properties of loops that can be shrunk to points on
the surface of the sheet. I think of the sheet as an n-genus manifold,
like a torus with n-handles. Your q-jump idea seems to imply that we can
jump from a n-tourus to a m-torus n=/=m. This is very controversial! I
would recommend that you read: Quantum Norm theory and the quantisation
of metric topology, by Isham, Kubyshin & Renteln, Class. Quant. Grav. 7
(1990) 1053-1074. I'll send you a copy if you would like.
> a) Cognitive spacetime sheetsglued to material spacetime sheet
> or larger cognitive spacetime sheet by *wormhole contacts*
> is the geometric counter part for subself of self: my mental image
> psychologically. Ideas in my head are cognitive spacetime sheets
> and ideas might float around everywhere as Sheldrake and
> meme theoreticians suggest. Very good ideas (from my
> point of view) might be enlightened Buddhas providing good vibes
> for a patient thinker.
I don't understand how you justify the concept of "cognitive space-time
sheets" :-( It looks like you are identifying an information structure
with a space-time sheet. To me this is overkill! The "mind" is defined
in terms of the information structure dual to a particular space-time
sheet. We do not need to posit a separate "sheet" for mind!
> b) Cognitive spacetime sheets can also get glued to other
> cognitive spacetime sheets by join along boundaries contacts.
> Join along boundaries contacts make possible *entanglement*: formation
> of larger wholes, associations.
Would the idea that "the boundary of a boundary is zero" apply here?
> Formation of JABs is topological synonym for direct touch. Join along
> boundariers contacts can also be long: the axons from sensory organ to
> brain could give rise to occasional formation of join along boundaries
> contacts between cognitive spacetime sheets in sensory organ and brain
> representing objects of perceptive field.
>
> I am now working with the model of brain. The strategy has been
> to invent all possible objections against *sensory organs as primary
> sensory experiencers* hypothesis. The strategy has been very successful.
> It has led to understanding of how TGD:eish brain computes part of
> sensory experiences and provided connection with hologram brain idea,
> which reduces to its bare essentials in TGD: neurons have neuronal windows
> to external world provided by axons where microtubules serve
> as wave guides making coherent light from sensory organs to propage
> to brain. Small piece of hologram <---> small window.
I like this spirit of this idea! I too am very interested in the
hologram paradigm! I am more focused on the Fourier symmetry and the
relationships between the generators of the reference beam and the
"reflecting object". I am interested in general principles not
particular examples...
snip
> > [MP] Why not try something more simpler and less radical: already
> > Riemann tried this but too early when he proposed that 3-space
> > is curved surface in 4-space. Start from the
> > age old problem of General Relativity. How to define energy and momentum
> > when spacetime is not curved anymore and does not possess Poincare group
> > as its isometries? What about spacetime as surface in M^4_+xS?
> > You get Poincare! Plus isometries of S, color group perhaps! And You
> > get generalization of string model too! This should make bell ringing
> > in every head thinking about theoretical physics! But it does
> > not. I am frustrated(;-).
It is one of the properties of Riemannian geometry, as I understand it,
that an "embedding" space is not necessary! I tentatively think of
energy and momentum as given by the degree of difference between a pair
of space-time framings that a given observer can have, e.g. when we
compare two observations of a given observer with the scale and clock of
that observer as its standard of "straightness" and minimal "duration",
the deviation of the two gives the energy. The way that an analog clock
is defined by the "face", the "hands" and an observer's comparison of
the two, follow this notion well!
I need to explain this in more detail!
> [SPK] I really would like to see this mental picture you have. I am just
> not bisimulating your thinking at all, I see too many contradictions, but
> that is, more than likely, due to my way of thinking... :-)
>
> [MP] I see also contradictions and this is why I am updating all the time.
> This is the only way to keep this big thing in control. I however dare
> say that contradictions are at the level of models and of
> interpretation now.
>
> I want to emphasize one important thing. My approach have been
> problem motivated: not an attempt to explain universe starting from some
> existing philosophical or mathematical paradigm: the
> mathematics and philosophy around TGD has developed painfully
> during 20 years.
You are not alone in this! My own naive thinking has been evolving for
15 years, ever since I first read books on GR and QM. We must be careful
not to become attached to any assumptions that, although beautiful,
ultimately are trivial. My dualism hypothesis is something that I am
very willing to dismiss, if it fails to be tenable. I feel that one of
the most important aspect of a theory is that it can, will due
diligence, be understood by anyone. I do not expect common sense to
reign! It is usually what gets us into trouble in the first place!
> The difficulties related to time concept are numerous and TGD solves
> them.
>
> a) The existence of reversible and irreversible worlds.
Show me a "real" "reversible world"!
> b) Nondeterminism of quantum jump contra determinism of Schrodinger
> equation.
How is it that we are so sure that the q-jump is "nondeterministic"? I
am very interested in how you define this notion.
> c) Loss of time in General Relativity
> d) The difficulties related to the definition of energy concept in General
> Relativity
> e) Difficulties in understanding the irreversibility of psychological
> time contra reversibility of geometric time of physicists: why
> we remember only past experiences.
It is astounding to me that the notion of "reversible geometric time",
idealistic as it is, carries more weight that the fact of experience! In
trying to get some verification of M. C. Mackey's work on
thermodynamics, I found that there is a fierce and even irrational
reaction to his "proof" that irreversible behaviors can not be gotten
from strictly reversible physical laws! That experience, combined with
the, at best, neglect fullness that has been shown to Hitoshi's work
makes me think that humans really do not wish to give up their
anthropocentrist stance!
> Typically colleagues do not start from these problems but see
> the problem as a highly technical one, which can be circumvented
> if sufficiently clever formalism is invented. Smolin's approach is
> typical example of this. He suggests a flaw on arguments showing
> that time is lost in GRT rather than starting from these big problems
> obvious to every graduate year student in theoretical physics.
> In string models situation is degenerated also to this kind of
> game.
This reaction to difficulties is typical; actually it is expected if we
consider that any given observer can only recognize patterns that are
similar to those that are within the set of their experiences! This
suggest a set of algebraic rules, like closure under unions, complements
and intersections, but I am not in a state of mind/body to figure out
the details right now... :-(
snip
> {SPK] The way that Pratt discusses how CABAs "collapse the whole algebra
> into a singlet" when a "new equation" is added, seems to me to relate to
> what you are saying! The difficulty that I see is that the "classification
> of 3-surfaces" is NP-Complete computationally! We can not just assume
> non-constructive arguments! I am thinking that each particular
> "experience" is a particular "classification" (a morphism from a subset
> of MEM to a subset of InfDimGeo, see below...) of a 3-surface. We can
> just assume that the 3-surfaces are "out there" already sorted for us.
> This thought is equivalent to the idea that there exist a single
> absolute space-time and all events are like bubbles frozen in the 4-cube
> and the subjective flow of time is an illusion! (See [time 623])
>
> [MP] I cannot say anything about about classification of
> 3-surfaces. What is however clear that NP completeness is based
> on a model of mind which relies on classical computationalism.
> And I am sceptic about this model of mind.
Have you looked up the definitions and applications of the NP-Complete
problem? Would it help if I wrote a post about it? Why do you consider
that NP-Completeness is "based on a model of mind which relies on
classical computationalism"?
> TGD mind corresponds to infinite quantum computer perfoming quantum
> computation of infinite duration during every 10^4 Planck times. The
> entire universe has infinitely long memory about its
> experiences: the number of quantum jumps occurred can quite well
> have cardinality much larger than that of integers of reals.
> Consider what this means when one introduces lexicons and generalizations
> of them! We should not assume that we are the master minds of the universe
> when trying to understand universe(;-)!
I need to better understand the specifics on how this idea of yours
works. I need explanations not declarations... For example: how do you
propose that the computation itself could be modeled? How do you take
into account Bremermann's limit?
(http://pespmc1.vub.ac.be/ASC/Bremer_limit.html) How is the information
encoded? How is the "infinitely long memory" accesses by the subsets of
the Universe?
Onward,
Stephen
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