| Subject: Peaceful co-existence of GR and thermodynamics?
Date: Mon, 17 Dec 2001 17:44:36 +0200 From: "Dimiter G. Chakalov" <dchakalov@surfeu.at> To: "Jeeva S. Anandan" <jeeva@sc.edu> CC: unruh@physics.ubc.ca, bdj10@cam.ac.uk, C.Anastopoulos@phys.uu.nl, c.isham@ic.ac.uk, newman@pitt.edu, Giovanni.Amelino-Camelia@cern.ch, i.raptis@ic.ac.uk, itamarp@vms.huji.ac.il, jb56@cus.cam.ac.uk, j.magueijo@ic.ac.uk, mario715@earthlink.net, stuckeym@etown.edu, Roderich.Tumulka@mathematik.uni-muenchen.de, youssef@bu.edu, Steven.Weinstein@Dartmouth.EDU, k.savvidou@ic.ac.uk, baez@math.ucr.edu, simo@mayu.physics.duq.edu, itin@math.huji.ac.il, ford@cosmos.phy.tufts.edu, roman@ccsu.edu, simon.saunders@linacre.oxford.ac.uk, msaniga@ulb.ac.be BCC: [snip] Dear Professor Anandan, Regarding your very interesting paper "Causality, Symmetries, and Quantum Mechanics" [Ref. 1], I asked you (email from Wed, 12 Dec 2001 02:29:32 +0100) for your insights on the cosmological constant problems: "Since gravity couples all forms of energy, what kind of action, and what sort of symmetries would explain the cancellation of all but one part in 10^(120)?" You replied (email from Wed, 12 Dec 2001 22:13:43 -0500) that do not have the answer for it. I can only speculate on some very general framework for including gravity, by introducing two modes of time, local and global, and speculating that both quantum waves and gravitational filed propagate in the putative global mode of time. To explain the case of gravitational field, let me first explain why I do not believe that GR is "the final word" about gravity. Please correct me if I am wrong. GR does not obey the conservation of energy. I will quote Matti Pitkänen at http://www.physics.helsinki.fi/~matpitka/illua.html "By Noether's theorem, conservation laws are in one-one correspondence with symmetries. In particular, translational invariance of the empty Minkowski space M^4 implies energy and momentum conservation in Special Relativity. By the basic postulate of General Relativity matter makes spacetime curved. This means that the symmetries of the empty Minkowski space are lost as are lost also (all? - D.C.) the corresponding conservation laws, in particular the conservation of energy." So we have another, even more puzzling 'peaceful co-existence', à la Shimony, of GR and thermodynamics: we do not observe on a daily basis any catastrophic events. (We do observe GRBs that would perhaps imply some exotic, negative" mass", but not at the scale of the macro-world of tables and chairs.) It seems to me that Einstein has been aware of this puzzle, since he did not consider his theory complete, http://members.aon.at/chakalov/readme1st.html#curvature So, I dare to suggest that gravity is *not* a curvature but an effect of the putative global mode of time, as explained at my web site. Even more: the 'chooser' (Pearle) of one propensity amongst many should be nothing but the mechanism of *quantum gravity* operating exclusively in the global mode of time. If we set the parameter describing the global mode of time to tend asymptotically toward zero, we can recover classical mechanics and Einstein's GR, but we can not, even in principle, reconcile QM and GR once they are separated at this scale. We can not reconcile QM with STR either, since at this scale there is no way to unravel the intrinsic global mode of time in the quantum realm: no time operator in QM. We can only talk about some puzzling 'peaceful co-existence', which is not good enough. If you're interested, I could elaborate more on the putative global mode of time, by trying to 'translate' some basic rules in cognitive science http://members.aon.at/chakalov/chakalov.htm#1 into your field of expertise. May I ask you to convey my kind regards to Professor Yakir Aharonov. I couldn't find his email address (if any), but it seems to me that he too believes in the global mode of time [Ref. 2]. It is quite a different matter that we can not observe its effect with inanimate devices: everything that we can physically observed is in our past light cone, so the global mode of time is wiped out ab initio. But we need it, don't we, to explain gravity. Professor Chris Isham has been stressing the need for a new quantum theory for over fifteen years, http://members.aon.at/chakalov/readme1st.html#Isham I will be happy to have your feedback, as well as that from all your colleagues who are reading these lines. With best regards, Dimiter G. Chakalov
References [Ref. 1] Jeeva S. Anandan. Causality,
Symmetries, and Quantum Mechanics. Foundations of Physics Letters,
15(5), 415-438 (2002),
[Ref. 2] Yakir Aharonov, Lev Vaidman (2001).
The Two-State Vector Formalism of Quantum Mechanics.
"One of us (YA) is not ready to adopt the far reaching
consequences of the MWI. He proposes another solution.
It takes the TSVF even more seriously than it was
presented in this paper. Even at present, before the "future" measurements,
the backward evolving quantum state (or its complex conjugate evolving
forward in time) exists! It exists in the same way as the quantum
state evolving from the past exists. This state corresponds to particular
outcomes of all measurements in the future."
=====
Dear Jeeva, In my email from Mon, 17 Dec 2001 17:44:36 +0200, which you can read at http://members.aon.at/chakalov/Anandan.html , I mentioned your paper "Causality, Symmetries, and Quantum Mechanics" [Ref. 1], which was first posted on Sun, 9 Dec 2001 05:16:28 GMT. I'm reading now the fifth version of your paper from Mon,
25 Mar 2002 01:07:40 GMT, and am still puzzled by the new kind of determinism
introduced in your interpretation of 'relational reality'. You wrote [Ref.
1]:
"This leads to the notion of relational reality or interactive
reality, namely that two objects exist in relation to each other if they
interact. According to this view, the state or wave function in which an
object 'exists' is meaningless if it is not interacting with another object.
It seems to me that the determinism in your relational (interactive) reality, expressed in the *change* of the interaction that subsequently determines the new explication of 'relational reality', presupposes a *third* possibility about reality: If not interacting with another object, the state or wave function in which an object 'exists' is that of 'potentialities', as suggested by A. Shimony and your colleague next door Prof. Y. Aharonov [Ref. 2]. This is certainly not a novel idea, it can be traced back to Aristotle and was endorsed by Heisenberg: "The wave function represents partly a fact and partly our knowledge of a fact", http://members.aon.at/chakalov/right.html#Note_2 Just replace 'knowledge' with 'potentialities', and call this kind of reality 'potential reality'. As you wrote in [Ref. 1], "The notion of stark, concrete, absolute reality that we use in our daily lives, according to which something *is* or is *not*, may be useful for our survival, for example, if we encounter a tiger in a jungle." Please note that it is not possible to "insert" the potential reality into the chain of states observed with measurements: the potential reality does NOT obey the law of excluding middle, as in the treatment of absolute reality as either "is" or "is not". It is a mixture (or shall I say superposition?) of the two possibilities, "is" and "not is", hence it is "the only mystery in QM" (Feynman). In other words, the potential reality can exist in a superposition (singular, not plural!) of a cat, a dog , http://members.aon.at/chakalov/Brukner.html#Joos , and a tiger in a jungle. Its wave function would be that of a pet with four legs and a tale. However, the wave function of 'the whole Universe' is unknowable, since it contains "absolutely everything" as One entity, http://members.aon.at/chakalov/chakalov.htm#1 Briefly, the potential reality must somehow 'stay available' for any *next* case of fixing the relational reality due to the change of interaction which explicates that relational reality. Hence the need for two modes of time, global (for potential reality) and local (for observed reality). The observed reality is fixed in our *past* light cone only, http://members.aon.at/chakalov/Youssef.html while the potential reality does NOT live on the spacetime. It is what creates the events, hence it is not included in the events constituting the spacetime, http://members.aon.at/chakalov/dimi.html Sorry for this long email, but I believe the potential reality is the only possible solution to the cosmological constant problems: Since gravity couples all forms of energy, what kind of action, and what sort of symmetries would explain the cancellation of all but one part in 10^(120) [Ref. 3]? You replied (email from Wed, 12 Dec 2001 22:13:43 -0500) that do not have the answer for it. My suggestion is to start with a type-IV scheme for quantum gravity [Ref. 4] and endow the set M of elements identified with spacetime 'points' or 'events' with a pre-geometry in the global time mode, http://members.aon.at/chakalov/Cahill.html#Ioannis I will appreciate your comments and suggestions, as well as those from your colleagues. Kindest regards, Dimi
[Additional references]
[Ref. 3] Norbert Straumann. On the Cosmological
Constant Problems and the Astronomical Evidence for a Homogeneous Energy
Density with Negative Pressure. Invited lecture at the First Séminaire
Poincaré, Paris, March 2002.
"Without gravity, we do not care about the absolute energy
of the vacuum, because only energy differences matter.
"I hope I have convinced you, that there is something
profound that we do not understand at all.
"For most physicists it is too much to believe that the
vacuum energy constitutes the missing two thirds of the average energy
density of the present Universe."
[Ref. 4] C.J. Isham (1993). Prima Facie
Questions in Quantum Gravity.
"IV. Both general relativity and standard quantum theory
appear only in certain limiting situations in the context of a theory that
starts from radically new perspectives. Very little is known about potential
schemes of this type or, indeed, if it is necessary to adopt such an iconoclastic
position in order to solve the problem of quantum gravity. However, the
recurring interest in such a possibility is based on the frequently espoused
view that the basic ideas behind general relativity and quantum theory
are fundamentally incompatible and that any complete reconciliation will
necessitate a total rethinking of the central categories of space, time
and matter.
"The bottom level is a set M whose elements
are to be identified with spacetime 'points' or 'events'. This set is formless
with its only general mathematical property being the cardinal number.
In particular, there are no relations between the elements of M
and no special way of labelling any such element.
"Finally, one might even imagine 'quantising' the point
set M itself: presumably by allowing quantum fluctuations in
its cardinal number.
"On the other hand, Diff(M) maps one spacetime point into
another, and therefore the obvious way of constructing a Diff(M)-invariant
object is to take some scalar function of spacetime fields and integrate
it over the whole of M , which gives something that is very non-local.
The idea that 'physical observables' are naturally non-local is an
important ingredient in many approaches to quantum gravity.
"The background Newtonian time appears explicitly in the
time-dependent Schroedinger equation (3), but it is pertinent to note that
such a time is truly an abstraction in the sense that no physical clock
can provide a precise measure of it [UW89]: there is always a small probability
that a real clock will sometimes run backwards with respect to Newtonian
time.
"3.3 The Use of Radical New Concepts "In the classification we have been using, a type-IV scheme is any approach to quantum gravity that starts with a view of quantum theory and spacetime physics that is radically different from that of conventional theories, and with the expectation that these standard ideas will emerge only in some limited domain. Almost by definition, schemes of this type dispense with much of the background structure of other approaches to quantum gravity, including, possibly, standard quantum theory as well as many normal spacetime concepts." ===== Subject: Re: Peaceful co-existence of
GR and thermodynamics?
Dear Jeeva, I'm glad to see that you're moving to Clarendon Laboratory, Oxford University, and I noticed that you too are taking the road to quantum gravity [Ref. 5] chosen by Chris Isham, http://members.aon.at/chakalov/Anandan.html#Isham May I draw your attention to a theory developed by Erasmo Recami and Ruy H.A. Farias [Ref. 6], which I quoted at http://members.aon.at/chakalov/right.html#Recami_2002 Perhaps you and/or some of your colleagues could take insights from their theory [Ref. 6] and propose an *exact* solution to the measurement problem, http://members.aon.at/chakalov/Adler.html#NB and hence explain why do we observe "points" in our past light cone, http://members.aon.at/chakalov/Butterfield.html It seems to me that the proper time (tau) introduced by Erasmo Recami and Ruy H.A. Farias [Ref. 6] is relevant to the the pseudo-time in Cramer's TI http://members.aon.at/chakalov/right.html#Cramer and to Kevin Brown's paper "Quantum Interactions on Null Surfaces", http://members.aon.at/chakalov/Jaroszkiewicz.html#5 Thus, to bridge the gap between QM and GR [Ref. 5] you may need to "live" on a null surface to make the elementary "step" of transience http://members.aon.at/chakalov/Booth.html#curvature You don't have this privilege in GR, http://members.aon.at/chakalov/Stachel.html#PS http://members.aon.at/chakalov/Wald.html http://members.aon.at/chakalov/Baez.html#now As explained eloquently by Robert Geroch in "Relativity from A to B": "There is no dynamics within space-time itself: nothing ever moves therein; nothing happens; nothing changes. [...] In particular, one does not think of particles as "moving through" space-time, or as "following along" their world-lines. Rather, particles are just "in" space-time, once and for all, and the world-line represents, all at once the complete life history of the particle." Perhaps the proper time (tau) [Ref. 6] is what we need to develop a compete theory of quantum gravity. As a bonus, we can have a theory of the brain, provided that the proper time (tau) matches what I call 'global time mode', http://members.aon.at/chakalov/dimi.html
Just a wild guess. You can read this email at http://members.aon.at/chakalov/Anandan.html#NB
Dimi
----
[To be published in Modern Physics Letters A] "A major problem therefore is to unify these two theories
in the sense that they are approximations of a deeper quantum theory of
gravity. Perhaps the deepest level at which the incompatibility between
the two theories is manifest is in the fact that general relativity is
local whereas quantum mechanics is non-local. This is reflected in the
formulation of general relativity geometrically in space-time, whereas
quantum mechanics is formulated in Hilbert spaces whose elements (state
vectors or wave functions) have non local properties in space-time."
[Ref. 6] E. Recami, Ruy H.A. Farias. A
simple quantum equation for Decoherence and dissipation (through interaction
with the environment).
"Second: the new discrete formalism allows not only the description of the stationary states, but also a (space-time) description of transient states." ====== Subject: Re: Peaceful co-existence
of GR and thermodynamics?
Hi Jeeva, I'm glad to see that in your recent paper "Laws, Symmetries, and Reality" [Ref. 7] you have extended your efforts into brain science and psychology: "Descartes' famous statement "I think, therefore I am" (Cogito ergo sum) created, despite Descartes' healthy skepticism of reality, a great deal of confusion in Western philosophy. "I think" means interactions between different parts of the brain, which therefore have relational reality with respect to each other. But concluding from this "I am," implying absolute reality of the self, is an unjustified extrapolation." I'm even happier to prove you wrong with your own brain, http://members.aon.at/chakalov/Vecchi.html The reality of the self is UNspeakable, and provides a clear framework for 'quantum reality', as implied in your question "when do we convert probability amplitudes into probabilities" [Ref. 7]. See my email of Thu, 20 Jun 2002 17:38:57 +0300 at http://members.aon.at/chakalov/Anandan.html#NB The story goes back to Plato, Leibnitz, Pauli, and Jung. It is amazing how physicists like you stubbornly refuse to consider these very old and widely known ideas, http://members.aon.at/chakalov/Peres.html#brain Needless to say, there is no room for 'absolute reality' in physics [Ref. 7], for the simple reason that the genuine 'closed system', or 'the only truly isolated system' which does not interact with anything, is ONE entity, the Aristotelian Unmoved Mover, http://members.aon.at/chakalov/Kuchar.html We can say nothing about this genuine 'closed system' because there is nothing to which it can be compared: all knowledge is relational, too. Hence the measurement problem in QM points toward theology, regardless of whether you like it or not. Same with the nature of 3-D space, http://members.aon.at/chakalov/Nature.html#note You can read this email also at http://members.aon.at/chakalov/Anandan.html#brain Soon on CD ROM "Physics of Human Intention". Take care, Dimi
Reference [Ref. 7] Jeeva Anandan, Laws, Symmetries,
and Reality, April 14, 2003,
"These and similar approaches to quantum theory were based
on two assumptions: A) There are quantum laws that apply to every physical
process, including the measurement process, and B) a system may exist by
itself and its reality does not depend on its interaction with other systems,
which I shall call the assumption of absolute reality.
"It seems reasonable therefore to suppose, instead, that
1) there are no fundamental causal laws but only probabilities for physical
processes that are constrained by symmetries, and 2) reality is relational
in that an object is real only in relation to another object that it is
interacting with.
"How and when do we convert probability amplitudes into
probabilities? Quantum mechanics provides a clear answer to the question
of 'how', namely the Born rule, but is infamously ambiguous about the question
of 'when'. We are told that probability amplitudes should be added or multiplied
when no 'observation' is made, and that the probability amplitudes should
be converted to probabilities when an 'observation' is made. But no clear
criteria for what constitutes an observation is given, apart from some
vague ideas about interaction with a macroscopic system.
"Even in classical physics, the reality of the electric
field is determined by what it does to a charge; the field is therefore
real with respect to the charge that it interacts with. The difference
between classical and quantum physics is that different charges respond
to a classical field like as if it is the same field, which gives the illusion
that the field is independent of its interaction with the charge. Whereas,
in quantum physics the states of two interacting systems become entangled,
in general, which should prevent us from assigning independent reality
to either state.
"Descartes' famous statement "I think, therefore I am"
(Cogito ergo sum) created, despite Descartes' healthy skepticism of reality,
a great deal of confusion in Western philosophy. "I think" means interactions
between different parts of the brain, which therefore have relational reality
with respect to each other. But concluding from this "I am," implying absolute
reality of the self, is an unjustified extrapolation."
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