Foundations of a theory of quantum gravity - Johan Noldus' book.

[S.Daedalus]

The point is that the motivation for them is deep and the argument as to why they are necessary is spread out over 40 pages. But again, you ask the wrong question: you think someone needs to give a ''proof'' that these radical thoughts are necessary (which is given) but this is not really needed and certainly not how science functions.

I'm not talking about 'how science functions', I'm just talking about my capacity of (and motivation for) understanding the statements made by Noldus. That is, there might be a vantage point from which things like 'electrons carried by an atom do not develop consciousness since the same atom is not excited in almost all different universes' make sense, but I can't see -- and there does not seem to be laid out -- a way to get there from here, and thus, I can only judge them from where I stand now -- which makes them appear either incomprehensible or nonsensical.

 

[Careful]

That is, there might be a vantage point from which things like 'electrons carried by an atom do not develop consciousness since the same atom is not excited in almost all different universes' make sense, but I can't see -- and there does not seem to be laid out --

Where is that written ?? What he says is the following: free elementary particles do not exist in any way between measurement, which is the usual thing in the copenhagen interpretation (but not so in Bohm de Broglie and path integral for example), but he gives it an extra twist. He says that the meaning of ''to exist'' is determined by strong correlations between alternatives in different universes. For example, humans exist because we do not get into a macroscopically distinct superposition. Free electrons do not, because they immediatly diffuse over length scales which are far larger than their classical radius. So what he says is that all these alternative electrons in different universes should not be seen as different possibilities for one and the same electron, but they are different electrons, period. This implies that the particle notion itself becomes fully dynamical and is not a static one such as is the case in ordinary QFT.

Electrons in a bound state however, can develop some ''consciousness'', because they are more localized. So in a double slit experiment for example, we shoot electrons out of a gun but what he says is that it is a priori wrong to assume that the same electron will land on the screen; the way an electron is defined for the screen may differ from the way it is for the gun.

Careful

 

[Careful]

One of my favorites

 

[S.Daedalus]

Where is that written ??

It's a footnote on p. 27.

I'm sorry to say, but your explanation doesn't help me very much. How can existence be defined wrt different universes (which one would generally take to be, in themselves, things that may or may not exist)? What does consciousness have to do with anything?

These concepts (existence, multiple universes, consciousness, etc.) and others like it are all philosophically highly contentious, they're used in what seems to be an extremely idiosyncratic fashion, and I can't see much of a connection to how I understand these terms, and how I think they are commonly used. So, there's my problem: how could I follow the course of the argument if there doesn't even seem to be a way for me to get to its starting point?

This isn't asking to 'dumb things down', just to clarify: For instance, how does Noldus' consciousness relate to consciousness as it is more usually used (e.g., that something is conscious if there is something it is like to be that something)? I keep being faced with such confusion in reading the paper, and it honestly makes following the argumentation a bit too frustrating. If one is to judge something as making sense, it must make sense to oneself, and for that, there must be some way to connect it to what one already can make sense of -- and this connection simply doesn't seem to be provided.

 

[Careful]

It's a footnote on p. 27.

I'm sorry to say, but your explanation doesn't help me very much. How can existence be defined wrt different universes (which one would generally take to be, in themselves, things that may or may not exist)? What does consciousness have to do with anything?

Sorry, my use of this language is standard: different universes generally means different terms in a superposition with respect to a pointer basis. In the path integral language, this pointer basis consists of the ''classical'' realities. The role of consciousness has been explained by Von Neumann, Wigner and Pauli long time ago. For example you may wish to ask what it means for the same cat to be in a superpostion when the only thing which you have are states formed by creation operators.

In the case of the free particle for example, one may start from a superpostion of the usual creation operators and call that a particle, now this superpostion will evolve, interact with the gravitational field and the meaning of the superpostion will change locally. For humans, this change is small relative to our own size, since we remain stable, but for particles this is not so. If this doesn't make sense to you, then I am afraid you have never understood quantum mechanics.

Btw. The meaning of the word atom is not the standard one here! By atom is meant a monad in the sense of Leibniz, this is not a ''particle'' at all.

 

[S.Daedalus]

The role of consciousness has been explained by Von Neumann, Wigner and Pauli long time ago.

None of which I recall saying anything about the consciousness of electrons; to the best of my knowledge, that's not something that's 'standard' to talk about. (As for the role of consciousness in quantum mechanics, I'm not convinced there is one, but that's a whole 'nother discussion -- I consider it a vestige of a once-perceived necessity of a sharp quantum-classical divide that has become obsolete thanks to the development of the decoherence picture.)

Anyway, I don't want to knock the paper -- merely make the point that, from where I am now, it is difficult to judge whether the ideas presented repay spending much time and effort on.

 

[Careful]

Let me clarify even further. In GR we have given up the notion of ''identity'' from the beginning by Mach principle. Identity depends upon interaction with environment, but then this begs the question, ''what assigns'' identity? In practice, the theorist does, just by hand. But this is not allowed you see, since the theorist is part of the universe. In quantum field theory, identity is already more mallow than it is in standard QM and more in line with Mach principle. That is, it is contextual but the superposition principle adds several difficulties: (a) there are no classical observers anymore in QG with sharply defined identity (b) the philosophy of asymptotic particles in QFT is not about giving them an identity prior to measurement but simply to say that you have one, once you measure it. Now, put away the classical observers, then what are you left with ? How to retreive identity in a holistic universe ? You need consciousness for that. But just like in Einstein's theory, consciousness should couple to the matter content. So, there is a ''nonlinear'' interplay between both.

So, consciousness has to arise from somewhere, it needs to have seeds. That is what Leibniz and Whitehead considered long time ago. Whitehead clearly thought that everything in the universe is conscious, but that doesn't imply that everything is intelligent or has a high awareness state.

The role for consciousness in QG is therefore much more prominent than it is in ordinary quantum mechanics where the problem of identity is left untreated but effectively substituted by an unphysical classical observer.

Btw, decoherence doesn't solve anything.

 

[Careful]

But why stumble upon some ''detail'' you have never really thought about as I can see? Why not continue technical reading? The paper is 11% philosophy, 30% physics and 59 % mathematics. Nevertheless, all your comments stick to these 11% in which you clearly had no ''education''.

 

[S.Daedalus]

This is helpful, thanks. I disagree on some key aspects, however, now I feel I understand somewhat better where you come from. (That consciousness needs to have 'seeds' is in particular one notion I would contest: just as life can come from non-life, a process is in principle possible by which consciousness may arise from non-conscious matter; but that discussion would probably take us too far afield.) This is the kind of thing I feel is missing in the paper: an effort to get everyone (or at least, a portion of people to whom the research might appeal) onto the same page; to clearly lay out the ground upon which the theory is going to be erected, especially since it seems very distinct from the soil in which most other QG programmes grow.

Edit: Ah, I didn't see your other comment before I posted this. Well, in this case, then, I guess everything is said between us.

 

[Careful]

Edit: Ah, I didn't see your other comment before I posted this. Well, in this case, then, I guess everything is said between us.

Well, you see. Here you are completely unreasonable and actually irrational. Concerning mainstream approaches nobody questions anything, people ramble about technical details which do not work out, hail philosophy which philosophers do not even talk about anymore for more than a century ! What happens here? You spend most of the time with philosophy which you still do not understand (because modern Whiteheadianism requires quite some study). For example: how can consciousness spontaneously arise ?? There is no way you can do that if you think hard enough about it ! But yeah, people just believe this silly dogma because it has been ingrained in their 19'th century thinking. You see, some people tell me they don't agree, but fact is they don't understand. There is a world of difference between those.

Likewise, people do not understand the meaning of general covariance even still today. There are even hundreds of people confused about that, a whole community !

Careful

 

[martinbn]

Can anyone (and would anyone) explain what the main ideas are? I mean in less than 160 pages.

 

[Careful]

Can anyone (and would anyone) explain what the main ideas are? I mean in less than 160 pages.

let me help a bit

In section 5 we learn that a new investigation to the relationship between spin and statistics has to be performed and that this has to occur in the context of the Clifford algebra. This leads to the investigation of ordinary second quantization of new types of Dirac equations. This excercise reveals some very surprising conclusions : (a) negative energies cannot be avoided within a traditional Hilbert space representation and the usual spin-statistics connection fails (b) to cure this there are two ways out (i) you go directly to nevanlinna spaces or you try to avoid nevalinna spaces and enlarge the theory by including Grasmann nuymbers. In the first case, there is no spin-statistics theorem anymore, but at least the correct connection is allowed for; in the second case, further computation reveals that either (i) you have to consider Nevanlinna spaces or (ii) a new principle of gauge invariance is required (for spin 1/2 particles!). I did not work out this last option and came to the conclusion that Nevanlinna spaces are unavoidable (there are of course the potential interpretational difficulties, but a constistent scheme worked towards in section 6). There are two further lessons which we learn from which the first one is at first sight dramatic. That is (a) there is no spin statistics theorem- not even in Minkowski (b) the whole math suggest to enlarge QFT with the Clifford numbers. With that last statement, I literally mean that we have to consider Clifford-Nevanlinna modules: which is a natural extension of quaternionic quantum mechanis fo Adler and Finkelstein to no-division algebra's. And a very natural one since all associative division algebra's (R,C,H) are Clifford algebra's. But what about the spin statistics relation? The answer to this question is remarkably simple, but no one has figured it out until now. If one looks into the proof of the spin statistics theorem of Weinberg, then you see that causality, Poincare invariance, positive energies and positive probability imply the spin statistics relation. But what is never said is that Poincare invariance, positive energies and positive probabilities and spin-statistics lead to causality. The idea therefore is to exchange causality for the spin-statistics relation and the proof that this point of view is superior to the original one results from the fact that one can weaken the restriction from Hilbert spaces to Nevanlinna spaces and still obtain the correct implication (while the reverse is false as mentioned before). Section seven contains so far a technically rigorous introduction to a very general kind of distribution spaces allowing for well defined scalar products The structures presented here give each observer his own topology and access to the universal module, the unitary equivalences are very weak and of the unbounded kind (which is typical for Nevanlinna spaces) so this framework is large enough to do rigorous QFT. One of the consequences of this investigation is that it is natural to drop the axiom of associativity which gives the mathematical framework an extremely broad scope; still some very stringent results can be obtained.

Ok, so all these ideas together is what I would call a first extension of free QFT, in total there are at least three non trivial ideas for the quantum theory alone (then I do not speak about gravitation yet). What do we do in section 8, well we construct an axiomatic foundation of a theory of quantum gravity. This means that we work out the kinematics, dynamics and part of the ontology. What are the crucial ideas?
(a) Local particle notions ! What do we mean with this and how do we realize this technically? There are several ways to understand this and let me give you one. We only know one particle notion and that is the one associated to a Fock space in the framework of a free theory on Minkowski: everyone who has understood this construction knows that it is inevitable and canonical (apart from the ''statistics theorem'' which gives you ordinary bose/fermi and which requires a number of assumptions we dismissed in section 7). Right, so if we want to have a fundamental particle theory, it seems like we are condemned to a free theory. Wrong ! The realization of how to solve this is the second non-trivial idea (and you immediately notice that if I can solve this problem, we can give a full nonpertubative formulation of interacting relativistic quantum theory). The idea is actually the same Einstein had when he got from special to general relativity: that is, you put ordinary free Minkowski on tangent space. Hence, we move free QFT to TM instead of M (M is the manifold); hence TM is the theater for reality and not M. This implies automatically that we have to pick the vierbein and not the ordinary metric for a theory of gravitation.

Now the development goes two ways - on one side you have in each point of space-time a preferred reference frame given by the vierbein, which gives you an infinite NOW that is isomorphic to the whole of M and on which lives a free relativistic quantum field theory. On the other side your need a new geometry as well as a new idea how to implement interactions. This requires the following:
(a) on the gravitation side you need a new connection having the appropriate transformation laws
under local (in M) Poincare transformations on TM
(b) you need new ideas for quantum theory.
Now concerning the classical gravitational theory (we come to the issue of gravitons later on), there are a number of important realizations: (i) it is a pure torsion theory (no Einstein tensor, the corresponding Bianchi identities are not adequate because of torsion) (ii) it is a non local theory, more specific the equations are ultrahyperbolic (how this is possible I explain within a minut) (iii) technically therefore it is much better to pass to a boundary value formulation instead of an initial value formulation. Ok, how can it be that these equations are ultrahyperbolic if we work with an ordinary vielbein as well as a Minkowski metric on TM? The answer is easy, but the interpretation as well as the consequences are far reaching. The simple answer is that the equations live on TM and not on M: you notice immediatly that you have two times (one coordinate time on M and one time in TM associated to the tetrad). Now, this appears to be going into the work of Bars, however it does not. That is, the ''time'' in the ultrahyperbolic equations is no time in the metric sense, it is a (linear) combination of space coordinates in the (linearization) of the field equations. Amazing enough, these equations have a 3+3 structure (two coordinates disappear but are recuperated in other equations - so the system is not underdetermined). Such multiple time idea in the naive sense is very problematic (since you think that three ''real times'' are necessary and one needs to make a compactification of two time directions) but here, no problem occurs since the metric on M is hyperbolic. Ok, we have performed a few consistency checks on the theory and also here, the conclusions are pretty radical (but not in contradiction to observation as far as I know): (a) if one gives up locality in gravitational theories, the 1/r^2 force law has no reason of existence anymore. Indeed, we knew already it had to be like that because of the anomalous galaxy rotation curves (where the MOND scenario offers an adequate way out). There is a kind of ''landscape issue'' here ( I don't call it a problem) in the sense that several different gravitational laws can exist within the same universe. To make a long story short: one can verify that short and long distance corrections to MOND are a possible solution (a short distance correction might be that you shut off gravitation on scales smaller than a millimeter and a long distance correction might exist in weakening gravitation where MOND becomes too strong). All those parameters can of course be chosen freely. There are two new classes of black hole solutions and strange enough, Einsteinian black holes are not solutions to the theory. One may guess that the usual no hair theorems do not apply and therefore, one does not have a simple first law of thermodynamics for black holes as is the case for general local metric theories. The physics of these blak holes is really different too: in general, gravitation is much stronger on the effective ''event horizon'' than it is in Einstein's theory. This offers possibilities for new exotic explanations for gamma ray bursts.

Ok, this is what we understood so far of the classical gravitational theory: a complete analysis of the mathematical structure of these equations will have to postponed to future work. Let me talk now about gravitons before we go over to the quantum theory. The only issue we want to treat here is the Weinberg-Witten theorem. So in my logic, gravitons are living on TM and belong to a free theory. Now, Weinberg-Witten says that no Lorentz covariant, conserved energy momentum exists for massless spin two particles. we agree that for a usual quantum gravity theory which is defined pertubatively around a fixed background, this is a death sentence. However, in this theory, it is a logical necessity. Indeed, gravitons are perturbations on a dynamical metric which is fixed through semi-classical equations wherein the relevant energy mometum tensor and spin tensor depend upon matter. Therefore, by definition, gravitons cannot contribute to the semiclassical equations! The conclusion therefore is that gravitons cannot ''gravitate'' but of course, the may belong tot the generators of the Poincare algebra. Weinberg Witten does not say anything about that ! These last generators are the Noether charges of the energy momentum + a graviton contribution. Obviously, gravtions may scatter and gravitate indirectly through interaction with matter. Therefore gravity has two faces, a non-local dynamical ontological side (geometry) and a local particle side (gravitons) and physics for both is essentially different. It is also clear that gravitons have an exceptional position within the particle spectrum.

Right, the quantum theory then, the ''main realization'' consisted in bypassing Haag's theorem as well as Coleman-Mandula. The whole idea is that we completely ''relativize'' quantum theory, therefore, away with foliations, away with global Hamiltonian and bye bye Heisenberg comutation relations (on M, not on TM !). All these ''technicalities'' have been major obstacles in case geometry becomes dynamical. Now well, you will say, what do you get into it's place and how do you retrieve ordinary relativistic quantum theory? It is clear that interactions have to be treated essentially different (due to Haag's theorem) and we are just not allowed to recuperate the ordinary Dyson series expansion. Let me reassure you from the start, yes ordinary free QFT is recuperated in an essentially unique way. The theory is constructed from relational ideas: to be brief, there exists something like a universal Clifford-Nevanlinna module which is constructed like a Fock space (she is time and space less). Of every particle species, there exists an infinite number of copies, to every space-time point and tetrad, one attaches the following quantum notions: *local* creation and annihilation operators (so things which the local observer can *measure*) and annihilation/creation operators for particles which you ''perceive'' in the rest of the universe (note that this requires an extension of representations of the Poincare group as constructed by Wigner, and a part of this analysis is already done in section 10). Moreover, one has a LOCAL vacuum state on which the creation/annihilation operators work as usual. Now, dynamics consists in changing particle notions from one spacetime point/vielbein to another spacetime point/vielbein by a general unitary transformation (what I would call a nonlinear Bogoliubov transformation). In other words, the kinematical object is a unitary transformation U(e_b(x),e_b(y),x,y) which depends upon two points and local reference systems. U(e_b(x),e_b(y),x,y) maps local particle notions to local particle notions, local vacua to local vacua and the ''rest of the universe'' to the ''rest of the universe''. One can consider a cycle of unitary mappings from x to y, y to z and z to x; it is trivial to demand that such cycle gives an identical result (other possibilities are discussed but appear to be unphysical). This allows one to write U(e_b(x),e_b(y),x,y) as U(e_b(x),x)U^{*}(e_b(y),y), in other words one has a unitary potential. However, these assumptions of associativity and the mere fact that the product is well defined only hold locally on a coordinate patch and fail globally; therefore the notion of state of the universe gets localized too to a family of compatible states which are each well defined on a coordinate chart only. This is a complete localization of quantum theory entirely in the spirit of general relativity. Now one has to find constraint equations for the unitary potential which requires a new physical idea: local Lorentz covariance. That is, you demand that the equations are invariant under quantum unitary Lorentz tranformations U(e_b(x),x) --> U^{*}(Lambda)U(e_b(x),x), which requires the introduction of a quantum spin connection (it is here that we kick Coleman-Mandula in the but). Anyhow, for U one has tor write down TWO equations instead of one (to ensure unitarity is preserved). This has to do with the Clifford Algebra and it is well know in Clifford analysis where you have something like a left-right monogenic Dirac equation DX = XD = 0, where D is the Dirac operator and X an element of the clifford algebra. There are no Heisenberg commutation relations on M (the spin-statistics information is on TM) and the whole dynamics is fixed by boundary data on a two sphere at infinity (because you have two first order equations in one variable - I did not perform yet the necessary integrability analysis here). This reminded me immediately at the holographic principle and also here one obtains the result that causality is a derived property determined by these boundary conditions. Now, we have verified that one retrieves from this theory ordinary free QFT on Minkowski uniquely (if one shuts off interactions) if one restricts to clifford scalars (these are the natural boundary conditions). Hence ordinary Minkowski causality on M follows from the dynamics as well as causality on TM.

 

[PhilKravitz]

Near the end he gets into dissing computers ability to think
"A computer could not even understand it in a relational
context; for example, take the definition of continuity for functions from R → R.
Give now the computer the function x → x and ask whether it is continuous.
I conjecture that the computer will never ever give an answer as quick as a
human will on these type of questions because it doesn’t know the meaning of
pick ǫ > 0, choose δ ≤ ǫ, then |y − x| < δ implies that |y − x| < ǫ."

Unless we are invoking some sort of Penrose QM mysticism about human thinking it is clear that machines can perform the same operations on information as human brains. I have to completely disagree with Johan on this point.

 

[Careful]

Near the end he gets into dissing computers ability to think
"A computer could not even understand it in a relational
context; for example, take the definition of continuity for functions from R → R.
Give now the computer the function x → x and ask whether it is continuous.
I conjecture that the computer will never ever give an answer as quick as a
human will on these type of questions because it doesn’t know the meaning of
pick ǫ > 0, choose δ ≤ ǫ, then |y − x| < δ implies that |y − x| < ǫ."

Unless we are invoking some sort of Penrose QM mysticism about human thinking it is clear that machines can perform the same operations on information as human brains. I have to completely disagree with Johan on this point.

I said as quickly as a human, many simple tasks we perform and deduct through insight take a computer a million of years unless you tell him of course how to think (that is give a part of the algorithm). Machines can indeed do this, but they will produce a lot of nonsense a human won't even consider! Isn't it paradoxical that a computer can compute a billion times faster than humans do the square root of three say while we humans can figure out a proof of a simple theorem a billion times faster than a machine !

I do not want to prove that AI is impossible, I think it is unlikely and the burden of proof is with you guys ! To produce a machine which thinks as fast as we do. I conjecture you will never succeed.

''Careful''

 

[PhilKravitz]

We are up to a machine that plays Jeopardy better/faster than humans. Time will tell.

 

[Careful]

We are up to a machine that plays Jeopardy better/faster than humans. Time will tell.

If you read the entire text, then you will see that in the end I make the distinction between a physical and hypothetical turing machine. I think physical turing machines are doomed, the hypothetical ones are not distinguishable in practice (that is a finite lifetime) from a genuine creative point of view. It are two different worldviews and the point is not whether you can prove one to be wrong or another one to be right I feel this is a mistake Penrose is making (as well as the AI people), the issue is whether your point of view is likely. While it is certainly more conservative, it is not very likely as far as I understand these issues (and I have spoken for a while to somebody who is researching these issues for many years). What you are doing is building more complex machines and algorithms, but this is not evolution you see, this is creationism. Your machines won't really improve without your input while we humans seem to do just fine without a creator.

 

[atyy]

One of my favorites

more mysterious than quantum gravity

 

[Fra]

I've refrained from commenting more as I haven't had time to read more of the paper yet. Several nights in a row I fell asleep without looking at the printout of the first bunch of papers.

It seems Careful has put some unusually deep thoughts into this and that alone is IMO worth some applauds! About the details and to what extent I really can share any of the reasoing I'm curious to find out, but so far I unfortunately didn't have the time. All I can do w/o reading more is guess.

Hopefully the thread won't tilt until I get around to skimming more.

/Fredrik

 

[Careful]

more mysterious than quantum gravity

Indeed, quantum gravity is much easier.

 

[atyy]

What happens to asymptotically safe QFTs in this framework, which should have a gravity dual according to AdS/CFT?

 

[Careful]

What happens to asymptotically safe QFTs in this framework?

First of all, the quantum theory is not a field theory. Field theory is only an approximation (like in string theory) to the extend that causality and cluster decomposition are only weakly violated (because the gravitational field is weak). It would be too long to explain why, but this implies that one does not have running parameters and so on (which of course does not mean that the couplings do not depend upon the momentum scale - on the contrary !). Hence, there is no renormalization problem. By construction, all quantum theories are asymptotically free (like QCD), so the approximating QFT (which is ill defined) will reasonably be also.

 

[atyy]

Thanks, the other question is what happens to the measurement problem in QM, and what is the interpretation of negative probabilities?

 

[Careful]

Thanks, the other question is what happens to the measurement problem in QM

I have no accurate answer to that, but I present some elaborated thoughts on how this problem could be solved. Actually, this problem is far more difficult than all the mathematics in the entire book.

and what is the interpretation of negative probabilities?

There are a few possible candidates which are currently being investigated. I suggest one in section 6 (which was also worked out by a french mathematician recently) but other more robust schemes are also possible. But, be reassured, this will be treated in utmost detail in the final version.

 

[Careful]

more mysterious than quantum gravity

Something even much more mystic http://www.youtube.com/watch?v=-AA5ZhLhkzs&feature=related

 

[Fra]

I want to first say that I haven't finished skimming even the first part but I managed a few pages last night, and it make take a couple of skimmings to get used to your use of the word conscioussness.

I have a simple question first that may help me understand your non-technical vision.

You write that you share penrose quest for the "objective collapse". And in that context you write "that conscious beeings, should agree more or less out outcomces of experiments".

1) Is it ok to assume that you by conscious beeing = any physical observer. (ie. any physical system, that observers it's environment?)

2) To agree about the outcome of experiments: Here I wonder, do you distinguish between, and if so how, between "having consistent" expectations of a future experiment, and encoding/holding consistent RECORDS of history (past experiments).

What I mean is that any observer, has an expectation (ie a prediction if you like) of the future. This may be revised once the future has passed. so I wonder if you think that different observers, must have the same expectations, or agree on historic events.

3) Regardless of which the case is above, how is the consistency or agreement inferred, and why which observers? Or do you, like I think Penrose does, simply take this to be a consistecy in the realist sense, ie. that does not need to by subject to inference by an conscious observer (to try to use your terminology).

/Fredrik

 

[tom.stoer]

Careful,

regarding

let me help a bit

In section 5 we learn that a new investigation to the relationship between spin and statistics has to be performed ...

Can you do me a favour and ask Noldus when talking to him next time ( ;-) if it's possible to write a short introduction with a summary in the spirit of your post #47 and update the paper on arxiv accordingly?

Tom

 

[Careful]

Careful,

regarding


Can you do me a favour and ask Noldus when talking to him next time ( ;-) if it's possible to write a short introduction with a summary in the spirit of your post #47 and update the paper on arxiv accordingly?

Tom

That might be helpful, the reason why I did not write it like this in the introduction is because many of these insights require further explanation and I was afraid they might confuse the reader at this point. Therefore, I opted for a more conservative approach in which I decided to follow the historical route. It is very difficult to find the right balance in such work because it is personal and I have received many contradictory advises.

But there will appear more of my thoughts on this in the FQXi submission I still have to hand in.

 

[Careful]

1) Is it ok to assume that you by conscious beeing = any physical observer. (ie. any physical system, that observers it's environment?)

Yes, here I go further than Penrose and ''dead matter'' can have a minimal form of consciousness too.

2) To agree about the outcome of experiments: Here I wonder, do you distinguish between, and if so how, between "having consistent" expectations of a future experiment, and encoding/holding consistent RECORDS of history (past experiments).

Both these things which you mention are a matter of dynamics and not of kinematics. For example if we both look at a frog, you may decide it is green while someone who is color blind may call it grey. What I mean with to agree on outcomes of experiments is that once an observer makes a record, this fact must be communicated to the other observers. They have no full free choice anymore, which they could have had if the first observer didn't measure in the first place.

What I mean is that any observer, has an expectation (ie a prediction if you like) of the future. This may be revised once the future has passed. so I wonder if you think that different observers, must have the same expectations, or agree on historic events.

No, not at all, every observer has a personal window on the entire universe and these windows certainly do not need to be consistent. Even more, the theory reveals that your personal expectation of the future (and experience of the past) is going to influence the probabilities of outcomes of your and other observers' future.

 

[Fra]

Yes, here I go further than Penrose and ''dead matter'' can have a minimal form of consciousness too.

Ok, I think I see what you mean, and I probably agree with this view.

Although I would not choose to use the word consciusness because a lot of people associate to the wrong things. Consciousness in the sense of how matter encodes and holds information and expectations of it's own environment is pretty much inline with how I view this.

I think a problem, is to make sure people don't misunderstand it. Even when you speak about physical systems as observers as I do too, a lot of people tend to associate observers with something that has a brain. This is why I think it may be dangerous to use the words you do.

But I suspect that I agree with your perspective.

What I mean with to agree on outcomes of experiments is that once an observer makes a record, this fact must be communicated to the other observers. They have no full free choice anymore, which they could have had if the first observer didn't measure in the first place.

This smells a little bit Rovelli RQM.

Who ensures that this "communication" is successful and results in an agreement? As far as I remember, Rovelli in his RQM paper says that the only way for two observers to compare their subjective observations, is to interact/communicate. But he assumes that this communication somehow follows QM, but he avoids intricate discussions of this. But then Rovellis ambition isn't to change or revise, just to find a reinterprettaion of existing formalism that he thinks is more suitable for his next step.

Anyway, thanks for your notes. Perhaps it will become clear as I look further in your paper.

your personal expectation of the future (and experience of the past) is going to influence the probabilities of outcomes of your and other observers' future.

Makes good sense to me, thanks for clarification.

Maybe more comments coming when I get around to go further in your paper.

/Fredrik

 

[Careful]

This smells a little bit Rovelli RQM.

But it is very different ! Rovelli lives in a one observer universe (Carlo's), in my case all observers live in the same one but the quantum theory nevertheless allows for different perceptions.

Who ensures that this "communication" is successful and results in an agreement?

By communication, I mean objective collaps of the wavefunction. It by no means implies agreement. Agreement has to be a dynamical effect; for example it might be that everybody sees the frog in a different color. For example, I am sure that my green is not the same as yours; agreement then arises because people are going to look for a more elementary way of understanding green. For example, by means of the wavelength.

But then Rovellis ambition isn't to change or revise, just to find a reinterprettaion of existing formalism that he thinks is more suitable for his next step.
/Fredrik

Yes, I have extended and revised QT in a substantial way; you have to, no choice !

 

[Fra]

By communication, I mean objective collaps of the wavefunction. It by no means implies agreement. Agreement has to be a dynamical effect; for example it might be that everybody sees the frog in a different color. For example, I am sure that my green is not the same as yours; agreement then arises because people are going to look for a more elementary way of understanding green. For example, by means of the wavelength.

What I meant is, if this "objectivity" inferred or emergent, or just present as some realist constraint on the theory?

I didn't go into all details on Penrose as although I think Penrose connection is interesting, I do not share his view. But I think Penrose idea is to implement the objective collapse as a form of constrain on the theory; so in his view I think it's NOT inferrred. It's just a conjecture (this is the sense in which he is a realist) that such an objectivity must exists somehow?

Penroses somehow tries to explain or get rid of the collapse by some objective thing (gravity in his case).

I OTOH, think gravity is rather emergent and that the collapsing wavefunctions is a key. So instead of finding some constraint that restores objectivity, I think objectivit and gravity is emergent and at say some level of equiblirium, this may be the flip side of the penrose coin.

Do you see it differently? If you don't have a simple answer to the fuzzy question we could get back to this when I had time to read more. I just see already now, that the details around this are strategic.

/Fredrik

 

[Careful]

What I meant is, if this "objectivity" inferred or emergent, or just present as some realist constraint on the theory?

Emergent.

I didn't go into all details on Penrose as although I think Penrose connection is interesting, I do not share his view. But I think Penrose idea is to implement the objective collapse as a form of constrain on the theory; so in his view I think it's NOT inferrred. It's just a conjecture (this is the sense in which he is a realist) that such an objectivity must exists somehow?

I always find it hard to say what someone else with brains thinks; but as far as I understand Roger, he simply says the collaps of the wave function is an objective process and not tied to one particular class of observers. I fully agree with him. This does not imply that objectivity of perception is not emergent.

Penroses somehow tries to explain or get rid of the collapse by some objective thing (gravity in his case).

I am afraid you misunderstood him here. The collapse is vital for his (and mine) interpretation of quantum mechanics; all he says is that there is a mechanism behind the collaps and that gravity is the origin of this mechanism. Here I disagree with him: for me, consciousness comes on the first place, not the second.

I OTOH, think gravity is rather emergent and that the collapsing wavefunctions is a key. So instead of finding some constraint that restores objectivity, I think objectivit and gravity is emergent and at say some level of equiblirium, this may be the flip side of the penrose coin.

Gravity is fundamental, you cannot get around that, and so is quantum mechanics. The standard model may be emergent.

 

[Fra]

(Just trying to tune it and see that I understand you correctly)

the collaps of the wave function is an objective process and not tied to one particular class of observers. I fully agree with him.

By class of observers, do you mean normal classification based upon references frame withing GR and SR context, or one based upon COMPLEXITY ie. human observer vs a subatomic observer?

/Fredrik

 

[Careful]

By class of observers, do you mean normal classification based upon references frame withing GR and SR context, or one based upon COMPLEXITY ie. human observer vs a subatomic observer?

/Fredrik

Aha, this is the interplay between classical and quantum! I mean dynamical reference frames (tetrads) determined by the expectation values of the matter currents in the state of the observer (as an identity within the ''state of the universe''). If you want to understand how this is possible: it are the local particle notions and local (infinite) windows on the entire universe which accomplish this.

 

[Fra]

the collaps of the wave function is an objective process and not tied to one particular class of observers. I fully agree with him.

By class of observers, do you mean normal classification based upon references frame withing GR and SR context, or one based upon COMPLEXITY ie. human observer vs a subatomic observer?

I mean dynamical reference frames (tetrads) determined by the expectation values of the matter currents in the state of the observer (as an identity within the ''state of the universe''). If you want to understand how this is possible: it are the local particle notions and local (infinite) windows on the entire universe which accomplish this.

I want to make sure I see it your way, and if it connects to how I would see it or not.

Do you somehow picture that one picture of the entire universe (or observable universe) encoded IN the state of the observer; and that IN this state, the first observer can identify let's call it "secondary observers" (maybe even so called elementary particles; as seen from the first observers "frame" or perspective) living coded on the system of complexions defined by the first observer, so that the collapse relative to these secondary observers, are "objective" relative to the first observer?

IE. almost a bit holographic view, where the dynamics of the state of the observer, in particular what it encodes, somehow mirrors or reflects the remainder of the universe?

But somehow the complexity of the mirror, or observer, bounds how much information that can be encoded. So it would correspond to a truncated holographic view. That the theory encoded IN the observer, doesn't necessarily describe the environment, but rather only the expectation of it - and in some cases these things will agree, and there would be a perfect holographic connection as a special case?

Usually I wouldn't expect this ot make sense to anyone else when phrased like this as as it's very fuzzy, but since your views may or may not be in this direction let's see if you connect and this is anything near what you attempt.

(I still haven't read more, just responded to the above, at best i'll read more later tonight)

/Fredrik