|
Author
|
Topic: Process and the Aether
|
Mark Szlazak
Member
Member # 391
|
posted 30. September 2002 15:00
For a talk that Henry Stapp gave at a Process Philosophy Conference on Q.M see his site. I believe one relevant paper has "Whitehead" in the title.
http://www-physics.lbl.gov/~stapp/stappfiles.html
Also, Dr. Stapp has just come back from a conference which had talks about Bohmian mechanics. I've asked him about this mechanics and he has posted his response and his troubles with this view. This relates to what I said earlier. Here's my e-mail and his response:
> Hello Dr. Stapp.
>
> Can Bohemian mechanics be made to work as an
> interpretation of Quantum phenomena as a
> strictly classical materialistic
> interpretation. If not why not and if so then
> why has this version not been widely accepted?
>
> Thanks. Mark Szlazak.
>
Dear Mark,
I just returned from a small conference attended by Basil Hiley, among a pestigious group of 17. An Oxford Philosopher of Science, (Saunders)asserted strongly a point that I have often made, namely that the theory has never been extended to the relativistic case involving particle creation. Hiley did not disagree, but I believe admitted that this was indeed the case. So that is one reason why the theory as it stands is
inadequate.
I have also a second criticism. An adequate theory must make predictions about empirical results of experiments. The way Bohm achieved this was to link his theory to Copenhagen ideas, and show that his theory gave the same results as Copenhagen. But the Copenhagen interpretation depends critically upon what von Neumann later called Process I. This is an intervention that is in principle not derivable from the unitary
evolution, but requires an outside choice of which experimental set up is to be selected from a (continuously) infinite set of alternative possibilities. Given that some good apparatus is in place Bohm computed the probabilities in his theory by showing that the relative probabilities of his Bohm trajectory entering the various
channels associated with the alternative possible outcomes of the experiment were just the same as the Copenhagen prediction that the corresponding outcome would be "observed." So if one associates the Bohm trajectory with human experiences then one achieves concordance between Bohm and Bohr.
But Process I is an intervention that Bohmian mechanics lacks. Hence that theory by itself gives no predictions!
To see the problem in more detail suppose we have an initial state of the universe that has been evolving since the big bang with no Process I interventions. Every physical object will be smeared out over a continuum of locations. Let's focus on the location of a Geiger Counter. The single location selected by a Process I intervention will be surrounded by a continuum of slightly displaced locations. For each of these possible locations there will be some probability that the Bohmian trajectory passes through the detection region. But there is a continuum of possible locations. So the total probability will be infinite. This is precisely the difficulty that the founders of quantum theory, and von Neumann, resolved by bringing in the Process I intervention, which picks out from the continuum of possible basis states generated by the unitary
evolution (Process II) some particular basis. Without this Process I intervention the theory gives no well-defined predictions: the unitary
evolution by itself, in conjunction with a Bohm trajectory, does not yield well-defined predictions pertaining to empirical/experiential
results. Process I interventions (or some other extra processes) are needed. The founders and von Neumann did not introduce this Process I intervention with no good reason.
This same criticism applies to the Everett-type theories.
Regards,
Henry
[ 30. September 2002, 21:21: Message edited by: Mark Szlazak ]
IP: Logged
|
|
Mark Szlazak
Member
Member # 391
|
posted 30. September 2002 21:33
See previous updated post.
IP: Logged
|
|
mturner
Member
Member # 190
|
posted 01. October 2002 07:54
**
Hi laurent;
I, too, reject dualism, be it Platonic or Cartesian. "Materialism" is monist, but unsatisfactory to me. Process Philosopy is also monist, but the contrary of monist Materialism, and so that is my chosen ontology. I feel that Process Philosophy and Materialism are antithetical to each other. Apparently you do not feel this way, but I don't see how you can justify that position.
My understanding of Materialism is that it holds that only the physical, that is, mass/energy, exists, that all else is illusory. That would make the aether either physical or illusory. If it is physical, how is it not matter? I do not deny the existence of a 'substrate', but I can only see that substrate as infinite Mind, not finite Matter.
Materialim denies Mind/Consciousness/Psyche/Spirit/Intelligence/Soulor whatever you wish to call those things it deems 'unmeasurable', that is, lacking the property of 'extension'. It contends that changes in extension are the only real changes. That would mean that only quantitative change is real, that qualitative change is illusory. It contends that change is nothing but mass in motion, while it is unable to explain either mass or motion.
Which leads back to Zeno's paradoxes, denying change entirely. And so on. At least, that's how I see it.
Well, that's it for now.
mturner
IP: Logged
|
|
Laurent
Member
Member # 425
|
posted 03. October 2002 14:06
Stapp sees human perception (consciousness) as a new added feature to reality, but I see it as the end result of an old evolving function of Nature, making Process I and II to be one and the same process.
I think the basic flaw in Bohm's theory is to believe there is a rich enough structure below the quantum level from where reality is to be projected (unfolded), to me it seems more reasonable that the information needed for particle creation would come from interactions at a spacetime level, above or at the quantum level.
I don't see why Process Philosophy and Materialism have to be antithetical, all process occurs at a material level, all we need an aether for is to provide for continuity, which is essential to process. Did you read what I think of mass, gravity and inertia. (A proton is made from condensed ordered space/information, when you split it you brake the order and get an explosion of space/information in the form of disordered radiation.)
[ 04. October 2002, 17:44: Message edited by: Laurent ]
IP: Logged
|
|
Laurent
Member
Member # 425
|
posted 05. October 2002 12:55
Matter and energy are properties of spacetime, and spacetime emerges
from the aether. The aether is a common substrate to matter, space,
energy AND mind.
There can't be any process without continuity, and there can't be
continuity without an infinitely divisible substrate.
--
Laurent
---------------------------------------
ETHER AND THE THEORY OF RELATIVITY
An address delivered on May 5th, 1920, in the University of Leyden
" How does it come about that alongside of the idea of ponderable
matter, which is derived by abstraction from everyday life, the
physicists set the idea of the existence of another kind of matter,
the ether? The explanation is probably to be sought in those
phenomena which have given rise to the theory of action at a
distance, and in the properties of light which have led to the
undulatory theory. Let us devote a little while to the consideration
of these two subjects.
Outside of physics we know nothing of action at a distance. When we
try to connect cause and effect in the experiences which natural
objects afford us, it seems at first as if there were no other
mutual actions than those of immediate contact, e.g. the
communication of motion by impact, push and pull, heating or
inducing combustion by means of a flame, etc. It is true that even
in everyday experience weight, which is in a sense action at a
distance, plays a very important part. But since in daily experience
the weight of bodies meets us as something constant, something not
linked to any cause which is variable in time or place, we do not in
everyday life speculate as to the cause of gravity, and therefore do
not become conscious of its character as action at a distance. It
was Newton's theory of gravitation that first assigned a cause for
gravity by interpreting it as action at a distance, proceeding from
masses. Newton's theory is probably the greatest stride ever made in
the effort towards the causal nexus of natural phenomena. And yet
this theory evoked a lively sense of discomfort among Newton's
contemporaries, because it seemed to be in conflict with the
principle springing from the rest of experience, that there can be
reciprocal action only through contact, and not through immediate
action at a distance.
It is only with reluctance that man's desire for knowledge endures a
dualism of this kind. How was unity to be preserved in his
comprehension of the forces of nature! Either by trying to look upon
contact forces as being themselves distant forces which admittedly
are observable only at a very small distance-and this was the road
which Newton's followers, who were entirely under the spell of his
doctrine, mostly preferred to take; or by assuming that the
Newtonian action at a distance is only apparently immediate action
at a distance, but in truth is conveyed by a medium permeating
space, whether by movements or by elastic deformation of this
medium. Thus the endeavour toward a unified view of the nature of
forces leads to the hypothesis of an ether. This hypothesis, to be
sure, did not at first bring with it any advance in the theory of
gravitation or in physics generally, so that it became customary to
treat Newton's law of force as an axiom not further reducible. But
the ether hypothesis was bound always to play some part in physical
science, even if at first only a latent part.
When in the first half of the nineteenth century the far-reaching
similarity was revealed which subsists between the properties of
light and those of elastic waves in ponderable bodies, the ether
hypothesis found fresh support. It appeared beyond question that
light must be interpreted as a vibratory process in an elastic,
inert medium filling up universal space. It also seemed to be a
necessary consequence of the fact that light is capable of
polarisation that this medium, the ether, must be of the nature of a
solid body, because transverse waves are not possible in a fluid,
but only in a solid. Thus the physicists were bound to arrive at the
theory of the "quasi rigid" luminiferous ether, the parts of which
can carry out no movements relatively to one another except the
small movements of deformation which correspond to light-waves.
This theory - also called the theory of the stationary luminiferous
ether - moreover found a strong support in an experiment which is
also of fundamental importance in the special theory of relativity,
the experiment of Fizeau, from which one was obliged to infer that
the luminiferous ether does not take part in the movements of
bodies. The phenomenon of aberration also favoured the theory of the
quasi-rigid ether.
The development of the theory of electricity along the path opened
up by Maxwell and Lorentz gave the development of our ideas
concerning the ether quite a peculiar and unexpected turn. For
Maxwell himself the ether indeed still had properties which were
purely mechanical, although of a much more complicated kind than the
mechanical properties of tangible solid bodies. But neither Maxwell
nor his followers succeeded in elaborating a mechanical model for
the ether which might furnish a satisfactory mechanical
interpretation of Maxwell's laws of the electro-magnetic field. The
laws were clear and simple, the mechanical interpretations clumsy
and contradictory. Almost imperceptibly the theoretical physicists
adapted themselves to a situation which, from the standpoint of
their mechanical programme, was very depressing. They were
particularly influenced by the electro-dynamical investigations of
Heinrich Hertz. For whereas they previously had required of a
conclusive theory that it should content itself with the fundamental
concepts which belong exclusively to mechanics (e.g. densities,
velocities, deformations, stresses) they gradually accustomed
themselves to admitting electric and magnetic force as fundamental
concepts side by side with those of mechanics, without requiring a
mechanical interpretation for them. Thus the purely mechanical view
of nature was gradually abandoned. But this change led to a
fundamental dualism which in the long-run was insupportable. A way
of escape was now sought in the reverse direction, by reducing the
principles of mechanics to those of electricity, and this especially
as confidence in the strict validity of the equations of Newton's
mechanics was shaken by the experiments with beta-rays and rapid
kathode rays.
This dualism still confronts us in unextenuated form in the theory
of Hertz, where matter appears not only as the bearer of velocities,
kinetic energy, and mechanical pressures, but also as the. bearer of
electromagnetic fields. Since such fields also occur in vacuo - i.e.
in free ether - the ether also appears as bearer of electromagnetic
fields. The ether appears indistinguishable in its functions from
ordinary matter. Within matter it takes part in the motion of matter
and in empty space it has everywhere a velocity; so that the ether
has a definitely assigned velocity throughout the whole of space.
There is no fundamental difference between Hertz's ether and
ponderable matter (which in part subsists in the ether).
The Hertz theory suffered not only from the defect of ascribing to
matter and ether, on the one hand mechanical states, and on the
other hand electrical states, which do not stand in any conceivable
relation to each other; it was also at variance with the result of
Fizeau's important experiment on the velocity of the propagation of
light in moving fluids, and with other established experimental
results.
Such was the state of things when H. A. Lorentz entered upon the
scene. He brought theory into harmony with experience by means of a
wonderful simplification of theoretical principles. He achieved
this, the most important advance in the theory of electricity since
Maxwell, by taking from ether its mechanical, and from matter its
electromagnetic qualities. As in empty space, so too in the interior
of material bodies, the ether, and not matter viewed atomistically,
was exclusively the seat of electromagnetic fields. According to
Lorentz the elementary particles of matter alone are capable of
carrying out movements; their electromagnetic activity is entirely
confined to the carrying of electric charges. Thus Lorentz succeeded
in reducing all electromagnetic happenings to Maxwell's equations
for free space.
As to the mechanical nature of the Lorentzian ether, it may be said
of it, in a somewhat playful spirit, that immobility is the only
mechanical property of which it has not been deprived by H, A.
Lorentz. It may be added that the whole change in the conception of
the ether which the special theory of relativity brought about,
consisted in taking away from the ether its last mechanical quality,
namely, its immobility. How this is to be understood will forthwith
be expounded.
The space-time theory and the kinematics of the special theory of
relativity were modeled on the Maxwell-Lorentz theory of the
electromagnetic field. This theory therefore satisfies the
conditions of the special theory of relativity, but when viewed from
the latter it acquires a novel aspect. For if K be a system of
co-ordinates relatively to which the Lorentzian ether is at rest,
the Maxwell Lorentz equations are valid primarily with reference to
K. But by the special theory of relativity the same equations
without any change of meaning also hold in relation to any new
system of co-ordinates K' which is moving in uniform translation
relatively to K. Now comes the anxious question: - Why must I in the
theory distinguish the K system above all K' systems, which are
physically equivalent to it in all respects, by assuming that the
ether is at rest relatively to the K system? For the theoretician
such an asymmetry in the theoretical structure, with no
corresponding asymmetry in the system of experience, is intolerable.
If we assume the ether to be at rest relatively to K, but in motion
relatively to K', the physical equivalence of K and K' seems to me
from the logical standpoint, not indeed downright incorrect, but
nevertheless inacceptable.
The next position which it was possible to take up in face of this
state of things appeared to be the following. The ether does not
exist at all. The electromagnetic fields are not states of a medium,
and are not bound down to any bearer, but they are independent
realities which are not reducible to anything else, exactly like the
atoms of ponderable matter. This conception suggests itself the more
readily as, according to Lorentz's theory, electromagnetic
radiation, like ponderable matter, brings impulse and energy with
it, and as, according to the special theory of relativity, both
matter and radiation are but special forms of distributed energy,
ponderable mass losing its isolation and. appearing as a special
form of energy.
More careful reflection teaches us, however, that the special theory
of relativity does not compel us to deny ether. We may assume the
existence of an ether; only we must give up ascribing a definite
state of motion to it, i.e. we must by abstraction take from it the
last mechanical characteristic which Lorentz had still left it. We
shall see later that this point of view, the conceivability of which
I shall at once endeavour to make more intelligible by a somewhat
halting comparison, is justified by the results of the general
theory of relativity.
Think of waves on the surface of water. Here we can describe two
entirely different things. Either we may observe how the undulatory
surface forming the boundary between water and air alters in the
course of time; or else - with the help of small floats, for
instance - we can observe how the position of the separate particles
of water alters in the course of time. If the existence of such
floats for tracking the motion of the particles of a fluid were a
fundamental impossibility in physics - if, in fact, nothing else
whatever were observable than the shape of the space occupied by the
water as it varies in time, we should have no ground for the
assumption that water consists of movable particles. But all the
same we could characterise it as a medium.
We have something like this in the electromagnetic field. For we may
picture the field to ourselves as consisting of lines of force. If
we wish to interpret these lines of force to ourselves as something
material in the ordinary sense, we are tempted to interpret the
dynamic processes as motions of these lines of force, such that each
separate line of force is tracked through the course of time. It is
well known, however, that this way of regarding the electromagnetic
field leads to contradictions.
Generalising we must say this: - There may be supposed to be
extended physical objects to which the idea of motion cannot be
applied. They may not be thought of as consisting of particles which
allow themselves to be separately tracked through time. In
Minkowski's idiom this is expressed as follows: - Not every extended
conformation in the four-dimensional world can be regarded as
composed of worldthreads. The special theory of relativity forbids
us to assume the ether to consist of particles observable through
time, but the hypothesis of ether in itself is not in conflict with
the special theory of relativity. Only we must be on our guard
against ascribing a state of motion to the ether.
Certainly, from the standpoint of the special theory of relativity,
the ether hypothesis appears at first to be an empty hypothesis. In
the equations of the electromagnetic field there occur, in addition
to the densities of the electric charge, only the intensities of the
field. The career of electromagnetic processes in vacuo appears to
be completely determined by these equations, uninfluenced by other
physical quantities. The electromagnetic fields appear as ultimate,
irreducible realities, and at first it seems superfluous to
postulate a homogeneous, isotropic ether medium, and to envisage
electromagnetic fields as states of this medium.
But on the other hand there is a weighty argument to be adduced in
favour of the ether hypothesis. To deny the ether is ultimately to
assume that empty space has no physical qualities whatever. The
fundamental facts of mechanics do not harmonize with this view. For
the mechanical behaviour of a corporeal system hovering freely in
empty space depends not only on relative positions (distances) and
relative velocities, but also on its state of rotation, which
physically may be taken as a characteristic not appertaining to the
system in itself. In order to be able to look upon the rotation of
the system, at least formally, as something real, Newton
objectivises space. Since he classes his absolute space together
with real things, for him rotation relative to an absolute space is
also something real. Newton might no less well have called his
absolute space "Ether"; what is essential is merely that besides
observable objects, another thing, which is not perceptible, must be
looked upon as real, to enable acceleration or rotation to be looked
upon as something real.
It is true that Mach tried to avoid having to accept as real
something which is not observable by endeavouring to substitute in
mechanics a mean acceleration with reference to the totality of the
masses in the universe in place of an acceleration with reference to
absolute space. But inertial resistance opposed to relative
acceleration of distant masses presupposes action at a distance; and
as the modern physicist does not believe that he may accept this
action at a distance, he comes back once more, if he follows Mach,
to the ether, which has to serve as medium for the effects of
inertia. But this conception of the ether to which we are led by
Mach's way of thinking differs essentially from the ether as
conceived by Newton, by Fresnel, and by Lorentz. Mach's ether not
only conditions the behaviour of inert masses, but is also
conditioned in its state by them.
Mach's idea finds its full development in the ether of the general
theory of relativity. According to this theory the metrical
qualities of the continuum of space-time differ in the environment
of different points of space-time, and are partly conditioned by the
matter existing outside of the territory under consideration. This
spacetime variability of the reciprocal relations of the standards
of space and time, or, perhaps, the recognition of the fact that "
empty space " in its physical relation is neither homogeneous nor
isotropic, compelling us to describe its state by ten functions (the
gravitation potentials g[greek subscript mu, nu]), has, I think,
finally disposed of the view that space is physically empty. But
therewith the conception of the ether has again acquired an
intelligible content, although this content differs widely from that
of the ether of the mechanical undulatory theory of light. The ether
of the general theory of relativity is a medium which is itself
devoid of all mechanical and kinematical qualities, but helps to
determine mechanical (and electromagnetic) events.
What is fundamentally new in the ether of the general theory of
relativity as opposed to the ether of Lorentz consists in this, that
the state of the former is at every place determined by connections
with the matter and the state of the ether in neighbouring places,
which are amenable to law in the form of differential equations;
whereas the state of the Lorentzian ether in the absence of
electromagnetic fields is conditioned by nothing outside itself, and
is everywhere the same. The ether of the general theory of
relativity is transmuted conceptually into the ether of Lorentz if
we substitute constants for the functions of space which describe
the former, disregarding the causes which condition its state. Thus
we may also say, I think, that the ether of the general theory of
relativity is the outcome of the Lorentzian ether, through
relativation.
As to the part which the new ether is to play in the physics of the
future we are not yet clear. We know that it determines the metrical
relations in the space-time continuum, e.g. the configurative
possibilities of solid bodies as well as the gravitational fields;
but we do not know whether it has an essential share in the
structure of the electrical elementary particles constituting
matter. Nor do we know whether it is only in the proximity of
ponderable masses that its structure differs essentially from that
of the Lorentzian ether ; whether the geometry of spaces of cosmic
extent is approximately Euclidean. But we can assert by reason of
the relativistic equations of gravitation that there must be a
departure from Euclidean relations, with spaces of cosmic order of
magnitude, if there exists a positive mean density, no matter how
small, of the matter in the universe. In this case the universe must
of necessity be spatially unbounded and of finite magnitude, its
magnitude being determined by the value of that mean density.
If we consider the gravitational field and the electromagnetic held
from the standpoint of the ether hypothesis, we find a remarkable
difference between the two. There can be no space nor any part of
space without gravitational potentials; for these confer upon space
its metrical qualities, without which it cannot be imagined at all.
The existence of the gravitational field is inseparably bound up
with the existence of space. On the other hand a part of space may
very well be imagined without an electromagnetic field; thus in
contrast with the gravitational field, the electromagnetic field
seems to be only secondarily linked to the ether, the formal nature
of the electromagnetic field being as yet in no way determined by
that of gravitational ether. From the present state of theory it
looks as if the electromagnetic field, as opposed to the
gravitational field, rests upon an entirely new formal motif, as
though nature might just as well have endowed the gravitational
ether with fields of quite another type, for example, with fields of
a scalar potential, instead of fields of the electromagnetic type.
Since according to our present conceptions the elementary Particles
of matter are also, in their essence, nothing else than
condensations of the electromagnetic field, our present view of the
universe Presents two realities which are completely separated from
each other conceptually, although connected causally, namely,
gravitational ether and electromagnetic field, or - as they might
also be called - space and matter.
Of course it would be a great advance if we could succeed in
comprehending the gravitational held and the electromagnetic field
together as one unified conformation. Then for the first time the
epoch of theoretical physics founded by Faraday and Maxwell would
reach a satisfactory conclusion. The contrast between ether and
matter would fade away, and, through the general theory of
relativity, the whole of physics would become a complete system of
thought, like geometry, kinematics, and the theory of gravitation.
An exceedingly ingenious attempt in this direction has been made by
the mathematician H. Weyl; but I do not believe that his theory will
hold its ground in relation to reality. Further, in contemplating
the immediate future of theoretical physics we ought not
unconditionally to reject the possibility that the facts comprised
in the quantum theory may set bounds to the field theory beyond
which it cannot pass.
Recapitulating, we may say that according to the general theory of
relativity space is endowed with physical qualities; in this sense,
therefore, there exists an ether. According to the general theory of
relativity space without ether is unthinkable; for in such space
there not only would be no propagation of light, but also no
possibility of existence for standards of space and time
(measuring-rods and clocks), nor therefore any space-time intervals
in the physical sense. But this ether may not be thought of as
endowed with the quality characteristic of ponderable media, as
consisting of parts which may be tracked through time. The idea of
motion may not be applied to it. " ------ Albert Einstein
------------------------------------------------------------------
Sir Edmund T. Whittaker in the preface to his scholarly and
scientific "A history of the Theories of Aether and Electricity"
published in 1951 said:
" As everyone knows, the aether played a great part in the physics
of the nineteenth century; but in the first decade of the twentieth,
chiefly as result of the failure of attempts to observe the earth's
motion relative to the aether, and the acceptance of the principle
that such attempts must always fail, the word "aether" fell out of
favour, and it became customary to refer to the interplanetary
spaces as "vacuous"; the vacuum being conceived as mere emptiness,
having no properties except that of propagating electromagnetic
waves. But with the development of quantum electrodynamics, the
vacuum has come to be regarded as the seat of the "zero-point"
oscillations of the electromagnetic field, of the "zero-point"
fluctuations of electric charge and current, and of a "polarisation"
corresponding to a dielectric constant different from unity. It
seems absurd to retain the name "vacuum" for an entity so rich in
physical properties, and the historical word "aether" may fitly be
retained. " ----- Sir Edmund T. Whittaker
-----------------------------------
In 1954 P.A.M. Dirac, a Nobel Prize winner in physics in 1933,
said -
" The aetherless basis of physical theory may have reached the end
of its capabilities and we see in the aether a new hope for the
future. " --- P. Dirac
-----------------------------------
The science popularizer Zukav writes -
" Quantum field theory resurrects a new kind of ether, e.g.
particles are excited states of the featureless ground state of the
field (the vacuum state). The vacuum state is so featureless and has
such high symmetry that we cannot assign a velocity to it
experimentally. " ---- G. Zukav
-----------------------------------
The very well known Tao of Physics by Capra states -
" This [quantum field] is indeed an entirely new concept which has
been extended to describe all subatomic particles and their
interactions, each type of particle corresponding to a different
field. In these 'quantum field theories', the classical contrast
between the solid particles and the space surrounding them is
completely overcome. The quantum field is seen as the fundamental
physical entity; a continuous medium which is present everywhere in
space. Particles are merely local condensations of the field;
concentrations of energy which come and go, thereby losing their
individual character and dissolving into the underlying field. In
the words of Albert Einstein:
" We may therefore regard matter as being constituted by the regions
of space in which the field is extremely intense ... There is no
place in this new kind of physics both for the field and matter, for
the field is the only reality. " ----- F. Capra
(page 210)
-------------------
All quotes came from -
http://www.blavatsky.net/confirm/ev/ether/etherEinstein.htm
&
http://www.blavatsky.net/confirm/ev/ether/ether.htm
IP: Logged
|
|
Laurent
Member
Member # 425
|
posted 20. October 2002 13:41
Perception is an old function of matter, dead or alive. Our brains became Nature's best perception tool only after billions of years of evolution.
This need for perception is what makes Relativity absolutely necessary for there to be a growth in knowledge and complexity, and the consequent formation and evolution of matter and all living organisms.
This is what triggered Einstein's interest in Bohm's 'undivided wholeness', he understood that for there to be a continuum, and therefore for Relativity to hold, the Universe must be conceived as a whole. He even became a Pantheist, he simply had no choice... Or why else would an object's dimensions depend on its surroundings if it wasn't for this wholeness? How was Nature to enforce symmetry if it wasn't through wholeness in space and time?
Relativity can only refer to RELATIVE time or length because it is the description of a WHOLE where every object is physically (energetically) related to each other. In other words, if an object could be conceived to be accelerating in a prefectly empty void or independently from any object or frame of reference it could not and would not experience any changes in time or length, but because it is embedded in a metric which represents the whole, objects do experience relativistic effects *in relation to others*. It is a property of the whole which arises from its physical need to abide by the laws of thermodynamics and the equivalency principle.
-----------------------------
*Gravitation is a deterministic process, the gravitational field is a classical non-quantized field.
*Gravity is not just another quantum field, gravity and collapse are interrelated.
*Gravity is caused by the radial space/information flow carried on by the continuos collapse of the particle/object wave-function.
It would seem as if Hawking and Unruh/Davies radiation are emissions created as uncertainty is being squeezed out of the system as it collapses into objective reality, but in reality it is a continuos information exchange between the collapsing matter fields and the surrounding inertial frame, since as they accelerate and condense they need to continuously reset the stress-energy tensor as the continuously changing quantum state and spacetime geometry will require, until they reach the objective state specified by the information previously gathered by the Schrodinger wave function.
In a semi-classical theory spacetime geometry couples to the expectation value of the stress-energy tensor
G_uv = 8pi(T^uv)psi
where PSI is the quantum state of the matter fields...
There are two separate processes involved, one is positive (expansive) and indeterministic, the other is negative (compressive) and deterministic.
In a process occurring within a Schwarzschild type spacetime geometry (black hole), and solving the Schrodinger equation for the matter fields in a continuos cyclical process where gravitation occurs only AFTER the measurement and is caused by the continuos collapsing of the wave-function, these two processes converge into a single, actual, objective solution in spacetime.
*The dynamics of the interaction will always depend on the quantum state.
[ 04. November 2002, 20:06: Message edited by: Laurent ]
IP: Logged
|
|
Mark Szlazak
Member
Member # 391
|
posted 22. October 2002 20:16
Since this currently is the "quantum thread" on the board, I'd like to post a response to an email that's up on Henry Stapp's site which talks about various interpretations of QT. I get confused reading the various books on this that claim there are alternatives to the "orthodox" view. Here's what Dr. Stapp says and I hope he expands the book he is working on to talk about so-called alternatives.
On Fri, 18 Oct 2002, Kathryn Blackman's Laskey wrote:
> Dear Henry,
>
> I hope all is well with you.
>
> Thanks very much for sending me this abstract.
>
> Regarding the book "The Mindful Universe" you sent recently, where is
> that being published?
It is still under construction. I've already had several offers
to publish it, but I'm holding off on deciding until the manuscript
is more readable to more people, and perhaps addresses more completely
the questions you ask below.
> I would appreciate your answering a question I have.
>
> There is much disagreement in the literature about the reduction
> process and how it works, including controversy over whether there is
> any such thing as reduction. I have read numerous statements from
> physicists that measurement involves interaction of a quantum system
> with its environment, and is (it is asserted) therefore "nothing but"
> Schrodinger evolution on a larger system.
This is wishful thinking not backed up by adequate supporting math.
This is essentially the Everett Approach. I have published my reasons for
claiming that this approach, after a half century of dedicated effort by
very many physicists, has not yet succeeded, technically.
[Can. J. Phys. 2002 SEP v80 N9 The basis problem in many-worlds theories,
pp.1043-105]
It is indeed widely advertized that the interaction with the
environment solves the measurement problem, But I do not believe
that the principal workers in that area (Zurek, Zeh, Joos)
actually make the claim that the whole theory has really been
worked out. I believe that the details have not been worked out
satisfactorily , and that the gaps are significant, and are
sufficient to undercut any strong claim that the Schroedinger equation
alone (and this includes the enviromental decoherence) is
actually sufficient, by itself, to tie the evolving state vector
to well-defined probabilities for human experiences, which is
what the orthodox (Copenhagen and von Neumann) formulations
achieve by explicitly introducing a second process tied to experiential
realities.
The reason, in brief, that a second process tied to experiential
realities is needed is that if the universe has been evolving
since the big bang solely under the influence of the Schroedinger
equation then every object and every human brain would now be, due
to the uncertainty conditions on the original atoms, represented
by a smeared out cloud, by an amorphous continuum. But in order to
extract from a quantum state a set of probabilities pertaing to
human experiences, and hence to give well defined empirical
meaning to the quantum state, one must specify a basis: one must
separate the space of the observing system into a set of discrete
orthogonal subspaces corresponding to different "observations";
i.e., into orthogonal subspaces corresponding to different distinguishable
experiences. But there is no detailed suggestion as to how
a set of particular orthogonal projection operator P are to be
specified on the basis of the amorphous state of the brain and
the continuous action of the Schroedinger evolution.
The problem, basically, is that a (proper) subspace is a set
of zero measure. For example, a subspace of dimension one in
a visualizable space of three dimensions consists of a single
line in the three-dimentional space. The definition of this
subspace must distinguish the vectors that lie along that line
from vectors that deviate from that direction by the the tiniest
amount. But how can a continuous amorphous structure distinguish
one direction from those lying arbitrarily close to it?
[For a higher-dimension example one can think of a plane in a three
dimensional space: again almost all points arbitrarily close
to any point in the plane will lie outside the plane.] Moreover,
the projection operator P cannot be local (confined to a point,
as contrasted to a smeared out region.) So how can a nonlocal
P be specified by a local process (the Schroedinger evolution
operator) acting upon a completely amorphous structure, the
evolved state. The founders (and von Neumann) seemed to recognize
clearly this basic problem of principle, and they introduced
a second process to resolve it. Any claim to have resolved
this claring problem of principle without bringing in another
process (besides the Schoedinger equation) needs to be
spelled out in detail. But this has not been done. Rather,
the environmental decoherence effect has been pointed to as
some sort of panacea. But that effect does not resolve the
problem at issue, but rather heightens it, by making it
effectively impossible, or nearly impossible, to use
empirical data to shed any light on the matter. The
environmental decoherence effect quickly reduces the density
matrix of macroscopic systems to NEAR diagonal form, but the
slightly off-diagonal elements in coordinate space hold
the continuum of diagonal states together in a continuous interlocked
structure. This structure does not break up purely dynamically into
a set of discrete regions. Any rule that breaks up this linked amorphous
structure in coordinate space into a set of discrete parts associated
with distinguishable experiences would seem very difficult if
not impossible to achieve solely by the dynamical process specified
by to the Schroedinger equation alone.
In any case this extraction of discrete subspaces from the
amorphous evolving quantum state needs to be described by those who
claim that the Schroedinger equation alone is enough.
> Bohm and Hiley say this in
> describing their hidden variable theory.
Bohm's pilot-wave model is another way to add onto the raw
theory an extra process to tie the raw theory into human
experiences in a quantitative way.
The main objection to that theory is that, in spite of
long-term intensive effort, it has not been generalized
to cover relativistic cases involving particle
creation and annihilation. Also, the connection of that theory
to experiment was based on the presumption that when the macroscopic
level of "pointers" was reached, the experience of the observer would
correspond to the branch of the pointer wave function that was "occupied
by the "trajectory". (Notice that this involves a second process, which
is explicitly linked to consciousness.) But this linkage is cast into
doubt by examples in which the trajectory goes through one detector but
it is the faraway dectector that fires. [ Dewdney, Hardy, and Squires,
Phys. Lett. A 184 (1993) 6-11]
I once asked Bohm how he answered Einstein's charge that his model
was "too cheap". He said that he agreed! And notice that the last two
chapters of his book with Hiley tries to go beyond this model. And
he, like I, saw the need to deal more adequately with Consciousness,
and wrote several late papers on the subject. And Hiley
is working on ideas that seem quite different from the old pilot-
wave model. I do not think any physicist actually working in the area
claims that the pilot-wave model really exists in the relativistic
domain.
> Others also say this,
> including people who don't subscribe to the Bohm pilot wave +
> particle ontology, such as Carver Mead in "Collective
> Electrodynamics," who gives a fairly well worked-out example of a
> quantum oscillator jumping an energy level, and how this can be
> explained by systems that briefly cross phases, exchange energy, then
> go out of phase again.
This book is checked out at UCB and is being ordered for me from UCSC.
But in any case quantum theory explains well how information is
transferred to measuring devices. But those clean descriptions
are the BASIS of the measurement problem, not the solution.
They do not explain how some object whose location is represented by a
(center-of-mass) wave function that is spread out over meters is
experienced as being located at nearly a point, and with some well
defined associated probability. If the device location is smeared out
then for each of a large continuum of device locations the device will
record the object as being "here." [Suppose the device has in addition to
its detecting ability also the capacity to determine and record its
location, and to correlated that information to the "detection" event.]
Its the same problem as before. Orthodox theory allows the detector to be
placed in some particular location corresponding to some particular
experience because the observer places it there, but an observer governed
solely by the Schroedinger equation has nothing definite about him: the
entire situation is a continuous smear with no dynamically defined
dividing lines. Some additional principle connected to the mind-brain
connection is needed.
> Dorit Ahranov in her review article on quantum
> computing also says that measurement involves Schrodinger evolution
> of the system and its environment. R. Mirman says "Wavefunctions
> don't collapse, oversimplifications do... Perhaps what collapses is
> not the statefunction, but common sense... Discontinuity cannot be
> true, and it is not. <aside from KBL... didn't people once think it
> could not be true that -1 had a square root, or that numbers could be
> less than zero?> But carelessness unfortunately can be true and too
> often is, and certainly can make discontinuity appear true." He goes
> on to amplify: "If for example we consider an object striking a
> screen forming a spot, the statefunction of the system after the
> formation, the product of that of the struck atom plus all objects
> attracted to it and the scattered object, is found from the initial
> one using Schrodinger's equation, and if so found would be seen to
> vary continuously. In principle it is possible to calculate final
> (perhaps extremely complicated) statefunctions from initial ones, and
> the entire transformation from one statefunction to another is
> completely continuous. Never is there a sudden change or collapse.
> Any such appearances result from ignoring the (continuous)
> intermediate stages by regarding these as happening instantaneously."
Yes! If process II is the whole story then there never is a sudden
change or collapse! Exactly true! But the continuousness of
that Process II evolution is closely tied to the fact that in a
universe evolving exclusively via the Schr. Eq., ever since the big bang,
the detector is everywhere, and the observer's brain is a smeared out
continuum of possibilities. I once, long ago, characterized the
many-worlds solution as shifting the whole measurement problem onto
the mind-brain problem, about which it says nothing. For the theory,
to be meaningful it must be tied to probabistic statements about
alternative possible experiences. But the smeared-out state
of the brain does not cleanly separate vectors from other vectors
that differ from them by very tiny amounts. What principle, involving
nothing but the evolving amorphous state, separates the space of brain
states into othogonal subspaces?
I do not claim that this problem has no solution. But Mirman's observation
that a world evolving via the Schroedinger equantion alone is evolving
continuously does not SOLVE the measurement problem: it CREATES the
measurement problem. Certainly, Heisenberg and Pauli and von Neumann
understood that a world evolving according to a universally valid Schr.
Eq. would evolve continuously. And they also understood that that did not
resolve the problem. I have absolutely no doubt that von Neumann
understood very well also the essential features of environmental
decoherence: they are all clearly displayed in his work. Yet in order to
get an empirically meaninful theory he brought in Process I.
>
> Mathematically, wouldn't it always be possible to embed a system in a
> larger system, and construct a Hamiltonian for the larger system such
> that measurement events occurred on the smaller system as a
> consequence of Schrodinger evolution on the larger system? Is there
> a way to test empirically whether the wavefunction "collapses" or
> whether it's "just Schrodinger evolution of a larger system?" Or are
> we discussing religious faith?
>
> Thanks!
>
> Kathy
>
The whole von Neumann approach involves assuming that the entire
physical universe, without Process I interventions, evolves in
accordance with Process II. That is the starting point. This will
certainly generate continuous evolution of "measurement" type
processes in subsystems. That is all automatic, and essentially trivial.
The problem, if no Process I interventions are included,
is to tie the amorphous structure generated by Process II to human
experience. That is a nontrivial mathematical problem that has
hardly even been addressed by many worlders (some unsuccessful
attempts were discussed in my Can. J. Phys. article) much less
solved. I think the top people see the problem, but they tend not
to emphasize it, but rather to hide it, and the followers are thus
unaware that there is a basic unsolved problem that renders the theory
a nontheory. at least now. But extracting discreteness from
an amorphous structure cannot be deemed a trivial matter.
As regards tests. it is certainly the case that living
systems that exploit the Quantum Zeno Effect in the way I
am suggesting, would tend to be more stable and directed than
a system evolving under the action of the Process II (Schr. Eq.)
alone. So there are, in principle, important empirical differences.
Actually, a properly constructed many world theory COULD be
essentially equivalent to the von Neumann theory. The point is that
a properly constructed many-worlds (actually one-world, many-minds)
theory needs, I believe, to specify orthogonal projection operators
corresponding to different distinguishable experiences, for only in this
way can the theory be adequately connected to experience. Suppose the
aspects of the brain associated with these P's are being periodically
monitored/observed by another part of the brain (e.g., the prefrontal
cortex). This monitoring would act like a measurement, and be represented
by a von Neumann Process I within the part of the space associated with
the original set of P's. And perhaps the monitoring action could itself
be associated with other experiences, for example, with a feeling of effort
or of high-level control of attention.
The point here is that I have continually stressed that Process I
is not controlled by any KNOWN law. But further developments MIGHT
tie it into Process II, plus some identifications of the connection
of the P's with experiences. But in the absence of any specific
suggestion as to how this would work it seems to me that von Neumann's
formulation is the best available theory. A mind-brain theory based upon
it would almost surely fit into a future theory that provides an adequate
explanation of the causal structure lying behind Process I.
IP: Logged
|
|
Laurent
Member
Member # 425
|
posted 26. October 2002 21:59
[Mark Szlazak]
Since this currently is the "quantum thread" on the board, I'd like to post a response to an email that's up on Henry Stapp's site which talks about various interpretations of QT. I get confused reading the various books on this that claim there are alternatives to the "orthodox" view. Here's what Dr. Stapp says and I hope he expands the book he is working on to talk about so-called alternatives.
On Fri, 18 Oct 2002, Kathryn Blackman's Laskey wrote:
[Kathryn]
> Dear Henry,
>
> I hope all is well with you.
>
> Thanks very much for sending me this abstract.
>
> Regarding the book "The Mindful Universe" you sent recently, where is
> that being published?
[Stapp]
It is still under construction. I've already had several offers
to publish it, but I'm holding off on deciding until the manuscript
is more readable to more people, and perhaps addresses more completely
the questions you ask below.
[Kathryn]
> I would appreciate your answering a question I have.
>
> There is much disagreement in the literature about the reduction
> process and how it works, including controversy over whether there is
> any such thing as reduction. I have read numerous statements from
> physicists that measurement involves interaction of a quantum system
> with its environment, and is (it is asserted) therefore "nothing but"
> Schrodinger evolution on a larger system.
[Stapp]
This is wishful thinking not backed up by adequate supporting math.
This is essentially the Everett Approach. I have published my reasons for
claiming that this approach, after a half century of dedicated effort by
very many physicists, has not yet succeeded, technically.
[Can. J. Phys. 2002 SEP v80 N9 The basis problem in many-worlds theories,
pp.1043-105]
It is indeed widely advertized that the interaction with the
environment solves the measurement problem, But I do not believe
that the principal workers in that area (Zurek, Zeh, Joos)
actually make the claim that the whole theory has really been
worked out. I believe that the details have not been worked out
satisfactorily , and that the gaps are significant, and are
sufficient to undercut any strong claim that the Schroedinger equation
alone (and this includes the enviromental decoherence) is
actually sufficient, by itself, to tie the evolving state vector
to well-defined probabilities for human experiences, which is
what the orthodox (Copenhagen and von Neumann) formulations
achieve by explicitly introducing a second process tied to experiential
realities.
The reason, in brief, that a second process tied to experiential
realities is needed is that if the universe has been evolving
since the big bang solely under the influence of the Schroedinger
equation then every object and every human brain would now be, due
to the uncertainty conditions on the original atoms, represented
by a smeared out cloud, by an amorphous continuum. But in order to
extract from a quantum state a set of probabilities pertaing to
human experiences, and hence to give well defined empirical
meaning to the quantum state, one must specify a basis: one must
separate the space of the observing system into a set of discrete
orthogonal subspaces corresponding to different "observations";
i.e., into orthogonal subspaces corresponding to different distinguishable
experiences. But there is no detailed suggestion as to how
a set of particular orthogonal projection operator P are to be
specified on the basis of the amorphous state of the brain and
the continuous action of the Schroedinger evolution.
The problem, basically, is that a (proper) subspace is a set
of zero measure. For example, a subspace of dimension one in
a visualizable space of three dimensions consists of a single
line in the three-dimentional space. The definition of this
subspace must distinguish the vectors that lie along that line
from vectors that deviate from that direction by the the tiniest
amount. But how can a continuous amorphous structure distinguish
one direction from those lying arbitrarily close to it?
[For a higher-dimension example one can think of a plane in a three
dimensional space: again almost all points arbitrarily close
to any point in the plane will lie outside the plane.] Moreover,
the projection operator P cannot be local (confined to a point,
as contrasted to a smeared out region.) So how can a nonlocal
P be specified by a local process (the Schroedinger evolution
operator) acting upon a completely amorphous structure, the
evolved state. The founders (and von Neumann) seemed to recognize
clearly this basic problem of principle, and they introduced
a second process to resolve it. Any claim to have resolved
this claring problem of principle without bringing in another
process (besides the Schoedinger equation) needs to be
spelled out in detail. But this has not been done. Rather,
the environmental decoherence effect has been pointed to as
some sort of panacea. But that effect does not resolve the
problem at issue, but rather heightens it, by making it
effectively impossible, or nearly impossible, to use
empirical data to shed any light on the matter. The
environmental decoherence effect quickly reduces the density
matrix of macroscopic systems to NEAR diagonal form, but the
slightly off-diagonal elements in coordinate space hold
the continuum of diagonal states together in a continuous interlocked
structure. This structure does not break up purely dynamically into
a set of discrete regions. Any rule that breaks up this linked amorphous
structure in coordinate space into a set of discrete parts associated
with distinguishable experiences would seem very difficult if
not impossible to achieve solely by the dynamical process specified
by to the Schroedinger equation alone.
In any case this extraction of discrete subspaces from the
amorphous evolving quantum state needs to be described by those who
claim that the Schroedinger equation alone is enough.
[Kathryn]
> Bohm and Hiley say this in
> describing their hidden variable theory.
[Stapp]
Bohm's pilot-wave model is another way to add onto the raw
theory an extra process to tie the raw theory into human
experiences in a quantitative way.
The main objection to that theory is that, in spite of
long-term intensive effort, it has not been generalized
to cover relativistic cases involving particle
creation and annihilation.
[Laurent]
Because they wanted to keep their process as local as possible, they were avoiding non-locality. They couldn't come to grips with the notion of Relativity that says that it is possible that the same two simultaneous events occurring in one given inertial frame of reference could be observed as sequential events in another frame of reference.
[Stapp]
Also, the connection of that theory
to experiment was based on the presumption that when the macroscopic
level of "pointers" was reached, the experience of the observer would
correspond to the branch of the pointer wave function that was "occupied
by the "trajectory". (Notice that this involves a second process, which
is explicitly linked to consciousness.) But this linkage is cast into
doubt by examples in which the trajectory goes through one detector but
it is the faraway dectector that fires. [ Dewdney, Hardy, and Squires,
Phys. Lett. A 184 (1993) 6-11]
I once asked Bohm how he answered Einstein's charge that his model
was "too cheap". He said that he agreed! And notice that the last two
chapters of his book with Hiley tries to go beyond this model. And
he, like I, saw the need to deal more adequately with Consciousness,
and wrote several late papers on the subject. And Hiley
is working on ideas that seem quite different from the old pilot-
wave model. I do not think any physicist actually working in the area
claims that the pilot-wave model really exists in the relativistic
domain.
[Laurent]
They can't exist because waves have been compressed flat by Lorentz contraction. At c or higher velocities time within objects stops until they are slowed down (absorved), but while in that state information is conserved intact and is fully absorvable by any 'observer'.
[Kathryn]
> Others also say this,
> including people who don't subscribe to the Bohm pilot wave +
> particle ontology, such as Carver Mead in "Collective
> Electrodynamics," who gives a fairly well worked-out example of a
> quantum oscillator jumping an energy level, and how this can be
> explained by systems that briefly cross phases, exchange energy, then
> go out of phase again.
[Stapp]
This book is checked out at UCB and is being ordered for me from UCSC.
But in any case quantum theory explains well how information is
transferred to measuring devices. But those clean descriptions
are the BASIS of the measurement problem, not the solution.
They do not explain how some object whose location is represented by a
(center-of-mass) wave function that is spread out over meters is
experienced as being located at nearly a point, and with some well
defined associated probability. If the device location is smeared out
then for each of a large continuum of device locations the device will
record the object as being "here." [Suppose the device has in addition to
its detecting ability also the capacity to determine and record its
location, and to correlated that information to the "detection" event.]
Its the same problem as before. Orthodox theory allows the detector to be
placed in some particular location corresponding to some particular
experience because the observer places it there, but an observer governed
solely by the Schroedinger equation has nothing definite about him: the
entire situation is a continuous smear with no dynamically defined
dividing lines.
[Laurent]
I agree, this is why I think it is a semiclassical process, an endless back and forth information exchange between the metric (spacetime continuum) and quantum matter (a Schoedinder wave evolving in curved spacetime). The Schroedinger equation for the matter fields must be solved according to the spacetime geometry, but then as the system continues to move in spacetime, the stress-energy expectation value needs to be reset to the new spacetime geometry, making it necessary to again solve for the new quantum state, and on and on into eternity.
[Stapp]
Some additional principle connected to the mind-brain
connection is needed.
[Laurent]
Gravitation?
[Kathryn]
> Dorit Ahranov in her review article on quantum
> computing also says that measurement involves Schrodinger evolution
> of the system and its environment. R. Mirman says "Wavefunctions
> don't collapse, oversimplifications do... Perhaps what collapses is
> not the statefunction, but common sense... Discontinuity cannot be
> true, and it is not. <aside from KBL... didn't people once think it
> could not be true that -1 had a square root, or that numbers could be
> less than zero?> But carelessness unfortunately can be true and too
> often is, and certainly can make discontinuity appear true." He goes
> on to amplify: "If for example we consider an object striking a
> screen forming a spot, the statefunction of the system after the
> formation, the product of that of the struck atom plus all objects
> attracted to it and the scattered object, is found from the initial
> one using Schrodinger's equation, and if so found would be seen to
> vary continuously. In principle it is possible to calculate final
> (perhaps extremely complicated) statefunctions from initial ones, and
> the entire transformation from one statefunction to another is
> completely continuous. Never is there a sudden change or collapse.
> Any such appearances result from ignoring the (continuous)
> intermediate stages by regarding these as happening instantaneously."
[Stapp]
Yes! If process II is the whole story then there never is a sudden
change or collapse! Exactly true! But the continuousness of
that Process II evolution is closely tied to the fact that in a
universe evolving exclusively via the Schr. Eq., ever since the big bang,
the detector is everywhere, and the observer's brain is a smeared out
continuum of possibilities.
[Laurent]
Perception is possible in Nature because there exists a smeared out continuum of possibilities (quantum matter).
[Stapp]
I once, long ago, characterized the
many-worlds solution as shifting the whole measurement problem onto
the mind-brain problem, about which it says nothing. For the theory,
to be meaningful it must be tied to probabilistic statements about
alternative possible experiences. But the smeared-out state
of the brain does not cleanly separate vectors from other vectors
that differ from them by very tiny amounts. What principle, involving
nothing but the evolving amorphous state, separates the space of brain
states into orthogonal subspaces?
[Laurent]
All we need is two separate matter states, two types of motion, one deterministic and the other inderterministic, objective and subjective, matter and quantum matter, particle-wave systems in a continuos exchange of information between matter and space, in an eternal quest for self-consistency.
[Stapp]
I do not claim that this problem has no solution. But Mirman's observation
that a world evolving via the Schroedinger equantion alone is evolving
continuously does not SOLVE the measurement problem: it CREATES the
measurement problem. Certainly, Heisenberg and Pauli and von Neumann
understood that a world evolving according to a universally valid Schr.
Eq. would evolve continuously. And they also understood that that did not
resolve the problem. I have absolutely no doubt that von Neumann
understood very well also the essential features of environmental
decoherence: they are all clearly displayed in his work. Yet in order to
get an empirically meaninful theory he brought in Process I.
[Laurent]
Anything and everything meaningful can exist only as an object in spacetime.
[Kathryn]
> Mathematically, wouldn't it always be possible to embed a system in a
> larger system, and construct a Hamiltonian for the larger system such
> that measurement events occurred on the smaller system as a
> consequence of Schrodinger evolution on the larger system? Is there
> a way to test empirically whether the wavefunction "collapses" or
> whether it's "just Schrodinger evolution of a larger system?" Or are
> we discussing religious faith?
>
> Thanks!
>
> Kathy
>
[Stapp]
The whole von Neumann approach involves assuming that the entire
physical universe, without Process I interventions, evolves in
accordance with Process II. That is the starting point. This will
certainly generate continuous evolution of "measurement" type
processes in subsystems. That is all automatic, and essentially trivial.
The problem, if no Process I interventions are included,
is to tie the amorphous structure generated by Process II to human
experience.
[Laurent]
This amorphous structure has to be tied to Nature's (the Universe's) experience, and that includes human experience.
[Stapp]
That is a nontrivial mathematical problem that has
hardly even been addressed by many worlders (some unsuccessful
attempts were discussed in my Can. J. Phys. article) much less
solved. I think the top people see the problem, but they tend not
to emphasize it, but rather to hide it, and the followers are thus
unaware that there is a basic unsolved problem that renders the theory
a nontheory, at least now. But extracting discreteness from
an amorphous structure cannot be deemed a trivial matter.
As regards tests, it is certainly the case that living
systems that exploit the Quantum Zeno Effect in the way I
am suggesting, would tend to be more stable and directed than
a system evolving under the action of the Process II (Schr. Eq.)
alone. So there are, in principle, important empirical differences.
Actually, a properly constructed many world theory COULD be
essentially equivalent to the von Neumann theory. The point is that
a properly constructed many-worlds (actually one-world, many-minds)
theory needs, I believe, to specify orthogonal projection operators
corresponding to different distinguishable experiences, for only in this
way can the theory be adequately connected to experience. Suppose the
aspects of the brain associated with these P's are being periodically
monitored/observed by another part of the brain (e.g., the prefrontal
cortex). This monitoring would act like a measurement, and be represented
by a von Neumann Process I within the part of the space associated with
the original set of P's. And perhaps the monitoring action could itself
be associated with other experiences, for example, with a feeling of effort
or of high-level control of attention.
The point here is that I have continually stressed that Process I
is not controlled by any KNOWN law. But further developments MIGHT
tie it into Process II, plus some identifications of the connection
of the P's with experiences. But in the absence of any specific
suggestion as to how this would work it seems to me that von Neumann's
formulation is the best available theory. A mind-brain theory based upon
it would almost surely fit into a future theory that provides an adequate
explanation of the causal structure lying behind Process I.
[Laurent]
I agree with most of what Stapp says, I just don't think Process I appeared later as a new process, I think it was always there but, like matter, has also evolved to become what today we know as consciousness.
[ 26. October 2002, 22:48: Message edited by: Laurent ]
IP: Logged
|
|
|
Printer-friendly view of this topic