Readers' Choice: The Crystallizing Universe

LC, You wrote: "The main point of a physical theory is to make predictions about measurable observables. The question on how we perceive time does far not a measurable quantity".

I see any performed measurement of time not a question of perception but clearly related to two more or less distant events in the past.

If someone attributes traces to the past then he considers the past as part of the abstract notion time that includes both past and future. Actually measurable are only the traces of past processes. This memory of traces altogether constitutes the unchangeable reality called the past in the sense of a contextual entity of partially predictable influences.

Is it correct to attribute observability to a concrete physical quantity? Definitely yes inside a model, however definitely no in reality. Predictions are more or less uncertain.

Eckard

Because English is not my mother tongue, I wonder why you wrote "far not". May I understand "not far" as almost?

Eckard,

The perceptions we have of space and time are in a way mental constructions. Barbour argues that time does not exist due to the fact the ADM Hamiltonian and momentum constraints NH = 0, N^iH_i = 0 have not time content. This extends to the Wheeler DeWitt quantum version HΨ[g] = 0. The set of diffeomorphisms of the theory are removed on the moduli space, and so identification of Diff(M) with time can't be established. However, I could equally suppose that time is a one dimensional space with a fibration of three dimensional manifolds we think of as space. I can further work out how these two pictures are in fact quantum complementarities.

In either case what we call space and time are not written in concrete at all. They are an aspect of an external degree of gauge freedom, or a coordinate choice on a frame bundle, which are chosen by the analyst or observer. They are not at all gauge covariant, and hence really do not constitute anything which can be called physically real. They are artifacts of a gauge choice, or in some sense constructed by the observer. In effect we "make them up."

As for the "far not," that is a mangled re-edit. The sentence "The question on how we perceive time does far not a measurable quantity, at least at this time," probably should read "The question on how we perceive time does not so far address a measurable quantity, at least currently."

Cheers LC

LC, Now I understand your sentence. Thank you. I even understand that Lorenz gauge condition is Lorentz invariant.

However, my caveat cannot be understood within the restriction to models of reality instead reality itself. A year is a reasonable objective measure. The number of years elapsed since my birth does not depend on any arbitrarily chosen gauge. Gauge redundancy and gauge arbitrariness do not matter in reality.

I agree: We made up what we are calling time.

However, the just elapsed time is an objective and measurable positive quantity with a natural reference point: Now.

Likewise, any shortest distance between two points in space cannot be negative.

Obviously my caveat is most fundamentally at odds with a lot of non-commutative, non-abelian theories that refer to the usual abstract and arbitrarily chosen notion of time which is not immediately linked with reality: Block universe, Poincaré synchronization, Lorentz transformation, Minkowski metric, Weyl's Eichinvarianz, ...

Regards,

Eckard

Supersymmetry is a way of interchanging internal symmetries with external symmetries. The internal symmetries are local gauge changes which introduce forces. External symmetries are the Lorentz group of boosts and rotations in spacetime. We are all familiar with the idea that internal symmetries are fictional: Take an electromagnetic vector A and add a gradient of some scalar A' = A gradX and we then have that the magnetic field B = -curlA' = -curlA - curl gradX, and the last term is zero. The difference is that with the external symmetries we have a sense of them and an arrangement of objects and ourselves with respect to each other in a spatial arrangement. Yet if internal and external symmetries are interchangeable it must mean their physical statuses are equivalent.

We are all familiar with curved spacetime, after all general relativity is nearly 100 years old now, but in fact we see little immediate presence of it. The curvature of spacetime due to Earth's gravity is 10^{-27}cm^{-2} --- tiny. By the same token we hardly have much sense that space is just a configuration variable for fields, and time is a parameterization of fields --- which are Lorentz covariant. Black hole change things a bit, for the observer outside the black hole witnesses physics according to an S matrix with a different domain than an observer who falls in with the quantum field of interest. The two observers witness the process according to entirely different representations, and yet in the end the core physics is the same. What is different is how the physical fields are "dressed," or should we say the particular moduli used.

In analogy with the dressing of quantum states and moduli, I could tomorrow put on a suit and head out to work. I could instead try something a bit different and put on a women's suit dress. The difference is superficial, for it is how the material folds and hangs on the underlying frame that is different --- the basic frame is the same, nothing fundamentally is different. Yet we tend to see the clothes, how the quantum states are dressed or the phase of the entanglement, as equal to the underlying quantum bits. Space and time share this property of being like the clothes.

Cheers LC

LC,

All your reasoning fits to the currently mandatory assumption of a block universe which is for instance explained in an extensive while nonetheless not convincing to me manner by Lebovitz in http://www.scholarpedia.org/article/Time%27s_arrow_and_Boltzmann%27s_entropy

Lebovitz admits that his view is opposed to the camp of "those who regard the passage of time as an objective feature of reality, and interpret the present moment as the marker or leading edge of this advance."

Lebovitz continues: "Some members of this camp give the present ontological priority, as well, sharing Augustine's view that the past and the future are unreal". Unfortunately I did not manage to convince proponents of this view that the present is a deliberately imprecise notion.

Lebovitz adds: "Others take the view that the past is real in a way that the future is not, so that the present consists in something like the coming into being of determinate reality". I see this view in accordance with Claude Shannon and the only reasonable view. I just wonder why apparently nobody dealt seriously with it.

Isn't my reasoning extremely uncommon but a bit more consequent and compelling? We both may agree on that the usual notion of time is just a mental construct while admittedly a very successful one. However, isn't it based on experience? Experience is necessarily restricted to the belonging past. Future events evade observation and measurement. Therefore, there is NO flow of time but a steady growth of elapsed time.

Reality is not invariant under shift. Invariance, covariance etc. are based on abstraction and therefore restricted to models. Physicists should learn to correctly interpret the results of their calculations.

Elsewhere I fond the utterance: "Mathematics dictates physics." I would like to object: It does definitely not dictate reality if its essence is its freedom.

Regards,

Eckard

Block time only makes sense in a classical setting. The idea of the crystallizing block time, or dynamics block time, involves the reduction of quantum states so that the present is something that is materializing. The hitch with this idea is that it means there is some contextual aspect to how quantum states decohere. In a measurement this contextual framework involves the eigenbasis the observer chooses according to how she orients an apparatus. Yet we know that quantum mechanics is non-contextual. This is one problem with the many world interpretation MWI). MWI posits the splitting off of the world according to separate eigenstates, but this can only happen in a contextual framework. Yet if the world is fully quantum mechanical there is no such context by which it splits itself off. So MWI buries the quantum-classical dichotomy more apparent in the Copenhagen interpretation in this subtle contradiction. This is the problem with the whole model here.

My main point is that we impose time as well as space onto the universe. What is physically relevant are the obstructions to flatness which might occur, which we call curvature. These are chosen according to the particular frame we elect to work in and observe the universe. There is no physical prescription which tells us how space is laid out or how time is to organize event in space.

Cheers LC

The attached represents my theory.

I have named my own model of the Universe, the Minverse Model (previously Coney Island Green, the name of the theory). See all below & attached.

I would be much greatful if the community consider this new model.

It is named Minverse (miniverse) because each mass entity acts as its own Universe, capable of creating space from mass.

Do not be afraid to believe in the theory.

Any questions, please contact me.

Douglas Lipp

Here are its claims (see also attached)

To Cosmologists and Theoretical Physicists,

The attached theory welcomes intense scrutiny and comment by experts.

Though the paper remains in need of further revision, nonetheless its current content is sufficient to promulgate research directed toward its firm confirmation. It is a "new model" of the Universe/Multiverse. The suggested term is the: "The Minverse Model" (short for miniverse, while at the same time in honor of my grandmother, Minerva).

The theory includes a mass to space quantification. It should be noted that the great physicist Faramarz Ghassemi was pursuing a similar mass to space view of nature. It is time other physicists take a serious look.

The theory offers in a "single view of nature", and "simultaneously", the following:

Varying Cosmological Constant

Possible explanation of Virtual Particles

Combination of the Spacetime Continuum with the Mass-energy equation

Quantification of mass to a spatial quantity

Solution to Dark Matter

Solution to Dark Energy

Solution to Horizon Problem

Solution to Red Shift Anomalies

Solution to Double Slit (Young's) Wave-Particle Duality Quantum Confusion

Physical explanation as to what E=mc² actually represents

New Interpretation of Einstein's Field Equations

True reason for Hubble expansion

Fourth Law of Motion Equating Gravity to Other Forces

Possible meaning of Plancks Constant

Lipps Law of Proportionality

Offers a New Explanation of Pressure

Is Relativitivistic in nature and therefore builds upon current science

Does not rely on extra dimensions

Does not rely on speeds greater than "c" as does current inflationary theory

Combines the Fundamentals (Matter, Time, Space)

Coherently respects conservation of energy (current view of expansion of space does not)

Above all else, the theory is experimentally verifiable.

Comments are welcome and can be delivered here or to lippfamily@earthlink.net

For a hard copy, please email the author.

Once again, the author apologizes for what appears to be a paper not altogether written in scientific/academic protocol.

Enjoy the "Fun" section as well.

Please open the attached to find: "The Coney Island Green Theory".

Thank You,

Douglas W. LippAttachment #1: 3_MTSFINAL15Rollover12.doc

LC,

Don't you consider Vesselin Petkov correctly stating that the timelessly existing block universe is the only one that is consistent with special relativity?

http://philsci-archive.pitt.edu/2408/

Regards,

Eckard

As a classical theory I could be disposed to this perspective. The block world in special relativity is of course the most direct. In general relativity this is a bit more complicated, but the block world is still the simplest to think about. The ADM approach to general relativity has some applicability, but I will not quibble the point here.

The problem comes with quantum mechanics. If reality is quantum mechanical all the way down, then the block world, even relational block world or crystallizing block world, becomes problematic. This depends upon some subtle issues with the foundations of quantum physics. In particular it depends upon an interpretation which has a problem with non-contextuality in QM. This puts a relational block world view in the same category as a quantum interpretation.

I suspect that quantum interpretations are in general false on some level, and this means all of them: Copenhagen, Bohm, Many Worlds, Consistent Trajectories and so forth. These quantum interpretations are also not testable, for they have no prediction of an observable consequence which can be observed to support them. They are not really theories in a proper sense.

The problem is that these interpretations are ways of trying to make quantum mechanics transparent within a classical mode of thinking. This really is a sort of intellectual security blanket or teddy bear. In order to pursue quantum gravity we are going to have to lay these things aside.

Cheers LC

LC, As I understood, the Hamiltonian formalism of ADM describes spacetime as space evolving IN time, and Lee Smolin comes from Deser.

Doesn't already the word IN imply an a priori existing time alias block time? When I was confronted with Ellis' emerging block universe, I appreciated the criticism of tenseless spacetime. However, up to now I did not understand how something emerging can be an priori given block. To me the two possibilities exclude each other, and the various attempts to unite them are altogether doomed to fail.

I tend to agree with Vesselin Petkov in that, the unrealistic block universe is an indisputable precondition for SR. While I am fully aware of the consequence to be put into the drawer of many many cranks, I see no reasonable alternative as to question SR and already Lorentz transformation. I will read arguments by Lucas and by Popper who, as I was told, called Einstein a Parmenides.

What about the foundations of quantum mechanics, I already investigated what I consider improper use of complex calculus by Heisenberg/Jordan/Born, Schroedinger/Weyl, and Dirac.

Regards,

Eckard

It is tempting to identify the foliation of spaces with a "time." However, what ADM relativity describes are a set of spatial surfaces which are related to each other by diffeomorphism. What has not really been done, as far as I know, is to demonstrate explicitly that this is time.

Classically the block time does make sense. It does have to be realized this is a model system, it is not necessarily the universe at its foundations. When you bring quantum mechanics into the picture this model gets shaken to its core. Attempts to revise the block time picture with MWI or other state reduction schemes runs into the subtle questions I outline above.

Cheers LC

Event horizons are null congruencies and are invariants. Everything else that is timelike transforms in a covariant or frame dependent way.

Cheers LC

LC,

Lepp pointed me to Ranzan who commented on the difference between length contraction just in the direction of motion as imagined by Lorentz and the just imagined one introduced by Poincarè and Einstein. I already read the same distinction made by Tom Van Flandern. While the mathematics of the block universe seems to be flawless, I tried to show in my essay that it does not fit reality.

You wrote: "Attempts to revise the block time picture ... runs into the subtle questions I outline above." May I replace "the subtle questions" by a fundamental contradiction?

Regards,

Eckard

This could be an outright contradiction. A revision of the block world within a quantum mechanical setting needs to overcome the polarity between contextuality and noncontextuality. A world with a present time slice which emerges as it evolves requires some sort of context in which quantum basis vectors are selected. Without some external control this has to be done by quantum mechanics itself. However, quantum mechanics is noncontextual, and it is difficult to see how the emergence of a present space with all the field data on it according to some contextual meaning to quantum states can emerge.

There may be some subtle issue involved that escapes our attention. Quantum mechanics has a complementary logic, and contextuality and its logical complement noncontextuality have some quantum dualism. However, how to frame such a possibility is not apparent to me.

In a classical setting block time is the most direct model. The problem of setting up a relational block world in a quantum setting seems to have some connection to issues of quantum gravity and cosmology. It will be interesting to see if the block time can be revised, or whether block world is a classical structure that amounts to excess baggage that is abandoned in quantum gravity.

Cheers LC

LC,

I wonder why even physicists apparently dislike the clear distinction between (R) a road in reality and (M) the ideal line that represents it.

I see the block universe an obviously not totally appropriate model, and I also suspect that QM is too much mathematically idealized.

On the other hand, John Lucas considered it worth to illustrate the correct argument by Saint Augustinus that there is no extended time slice between past and future. Not just Einstein wrongly attributed the usual notion of "simultaneity" to simultaneous perception. What nonsense! The only reasonable idea of simultaneity can be explained with a fair duel where the bullets meet exactly in the middle.

While I do not hate anybody, I admire Karl Popper who not just called Einstein Parmenides, i.e. as wrong as Zeno but who also admitted hating Hegel, and I recall Marx speaking of "abstruse Hegelei".

Backed by Popper, I am pretty sure: The block universe is strictly speaking fundamentally wrong but might nonetheless be useful as a model to some extent.

What about noncontextuality, I admit being ignorant of the related and perhaps controversial theories. I merely guess, the real world could not be convincingly described without contextuality.

What about the logical complement, I would like to remind of what I consider flaws in the fundamentals of set theory.

Regards,

Eckard

Quantum mechanics is to physics almost what logic is to mathematics. It is a system which determines the relationships between qubits in a logico-algorithmic sense. The relationship to classical mechanics or macroscopic physics is what is odd. Of course the macro-world might just be some approximation that we observe in a coarse grained sense. Everything may in effect be quantum mechanical at all levels.

The block world and Einstein concept of time works fine in a classical setting. The thing which muddies the waters is quantum mechanics, and this is compounded by quantum gravity. Quantum mechanics is noncontextual, which means the eigenbasis the state vector is expanded in is not determined quantum mechanically. The context is determined by the observer, such as by the orientation of a Stern-Gerlach apparatus. So the context assigned to quantum outcomes of measurements is determined by the observer in a classical or macroscopic setting. The crystallizing block world in an MWI sense means the present that is materializing involves a set of eigenbranchings, where the "branches" are according to eigenbasis vectors with some contextuality. In the teleportation of states the classical content involves this contextual element, Alice telling Bob how she oriented her SG apparatus. How this happens in a purely quantum mechanical setting is unclear.

The issues of simultaneity and the rest in relativity are pretty clear, and there is no controversy with respect to those results. I have also regarded the Zeno paradox as a funny thing that anyone should ever get wrapped up in. It always struck me as something overcome by calculus, and I think there was some proof to this effect using Robinson numbers derived a couple of decades ago.

As for Hegel, I suppose in keeping with his dialectics I both admire and dislike his work. In some sense what he said is true, and quantum mechanics is an example of Hegelian dialectics. The problem is that Hegel offered no method for using dialectics in some proper fashion. In fact I doubt anything like that could be founded. The founders of QM did not marinate themselves in Hegel before realizing the complementaritiy of QM. Hegel was also more concerned with social issues, which were in flux at his time with the French Revolution and Napoleon. That got taken up by Engels and Marx in a somewhat "loosy-goosy" fashion, but which motivated a lot of unfortunate political stuff in the 20th century.

Cheers LC

LC,

Hopefully you will agree with me that perception as well as measurement must be corrected for possibly different delays. I infer from this that Einstein's justification of Popincaré's (de)synchronization is not logical.

Hopefully you will not agree with G. Cantor on that something that is neither smaller nor equal to something must be larger. Logics allows a fourth possibility: incomparability.

Do we need a quantum logic? Having the textbook "Particles and Paradoxes - The limits of quantum logic" by Peter Gibbins at hand, I tend to deny that.

You are reiterating what is presently common opinion: "QM as well as SR are of eminent importance for modern physics. Therefore they must not be wrong."

-- Really?

You wrote; "Quantum mechanics is noncontextual, which means the eigenbasis the state vector is expanded in, is not determined quantum mechanically."

-- Isn't such expansion arbitrarily assumed?

You continued: "The context is determined by the observer, such as by the orientation of a Stern-Gerlach apparatus. So the context assigned to quantum outcomes of measurements is determined by the observer in a classical or macroscopic setting."

-- This reminds me of Heisenberg's likewise unacceptable interpretation: The path becomes reality if we measure it. Aren't state vectors and the like just abstract models? Could a point or a line become reality? I say no.

-- Maybe I am naive when I consider non-contextuality an simplifying idealization but context about the same as objective while possibly even sub-threshold influences. How do state vectors account for processes and for the embedding of any particle into reality?

You argued: "The crystallizing block world in an MWI sense means the present that is materializing involves a set of eigenbranchings, ... "

-- I desperately hope for understanding: Strictly speaking there is no present.

"... where the "branches" are according to eigenbasis vectors with some contextuality."

-- Isn't this a rather awkward and incomplete substitute for an admission of incalculable influences?

"In the teleportation of states the classical content involves this contextual element, Alice telling Bob how she oriented her SG apparatus. How this happens in a purely quantum mechanical setting is unclear."

-- At least to me the Alice/Bob metaphor is perhaps inappropriate.

Let me summarize: Zeno's flawed arguments indicate that Parmenides/Einstein (the block universe) is strictly speaking wrong. The putative necessity to use i in QM indicates a related and similar flaw in QM. In both cases, an abstract model is arbitrarily equated with reality.

At least laymen might be ready to understand: While time can be shifted, reversed, or otherwise manipulated in a record, a mathematical model, and the like, it cannot be influenced at all in reality. Why? Because pictures are abstractions that will never fully substitute the complete embedding into real life.

Regards,

Eckard

Eckard,

You wrote to Lawrence: "Hopefully you will not agree with G. Cantor on that something that is neither smaller nor equal to something must be larger."

This is another way of saying that a calculated result must be positive, negative or zero.

"Logics allows a fourth possibility: incomparability."

That's why quantum logic works. Logic in which value is assigned to undecidability allows a superposition of states. "Incomparable" quantities are undecidable -- a measured quantum result is always positive or zero.

Tom

Eckard & Tom,

I suppose you are referring to the Banach-Tarski paradox or the addition of transfinite numbers. The axiom of choice (AC) does involve the well ordering of a set. Hilbert space exists because of the AC. The Schmidt orthogonalization procedure employed in quantum mechanics and the theory of Banach-Hilbert spaces is an algorithm which works because the space is well ordered. This is a sort of choice function.

I have been working on the integer partition theorem. Given an integer n, there exists a set of integers (n1,n2,...) which add up to n, and then there are other sets as well, and the number of these sets is the partition. This has physical implications for how microstates of a black hole can be arranged amongst n Planck areas on the event horizon. The partition number grows approximately exponentially for the number of integer sets which sum to n as n --> ∞. Consequently, the set of all possible integer partitions for the integers is a power set, which is an C = 2^{X_0} result. X = aleph

The AC is an undecidable proposition as well. Some research was done on this, which I know about but I don't have references available, and it was found that the AC is not a consequence of the other axioms in ZF. The axiom of replacement I think has a similar property.

The AC does result in some quirky results though. A sphere can be decomposed in a certain way, group rotations (eg SO(3)) performed, and the pieces further decomposed and rotated, and ... infinitely onwards. The pieces may then be reassembled to construct two spheres identical to the first. This is the result of Banach and Tarski.

Some mathematicians consider the Banach-Tarski theorem to be a reducto-absurdum argument against the AC. That's one of the reasons for considering other axioms. The Perfect Set hypothesis "Every uncountable subset of the real line has a non-empty perfect subset." is inconsistent with the AC and seems just as intuitive. This gets into the subject of Polish spaces. However, in what I do it is not my interest to rewrite the foundations of mathematics.

Special relativity and quantum mechanics are "true" in the same way that Newtonian mechanics is "true." They both work in a broad domain of observation and have been extensively tested. There really are no controversies over the issue of simultaneity and clock synchronization. I worked on problems related to the question of synchronizing clocks for GPS and various other satellites. That gets more complicated with general relativity, but there are no serious controversies with the basic issues. Much the same holds with QM, and recently an experimental version of the Kochen-Specker theorem on quantum nonlocality was performed and the KS result supported.

My take on the issue of space and time is they are configuration variable representations which have a type of complementarity. This being the case there is no physical axiom which can tell us which of these is "real." Fundamentally there is no such axiom, and the observer imposes the context upon which is real, or how the two are related to each other. Classical spacetime does not share this feature, which is why in the classical domain you can talk about a block time.

The complementarity of space and time and the quantum mechanics of black holes could have had a much earlier start. At the 1930 Solvay conferences Neils Bohr and Albert Einstein debated the nature of quantum mechanics. Einstein was convinced of reality and locality and argued staunchly for an incompleteness of quantum mechanics. Quantum theory could only be made complete if there are some hidden variables that underlay the probabilistic, nonlocal quirky aspects of quantum mechanics. Einstein proposed an interesting thought experiment. Einstein considered a device which consisted of a box with a door in one of its walls controlled by a clock. The box contains radiation, similar to a high-Q cavity in laser optics. The door opens for some brief period of time t, which is known to the experimenter. The loss of one photon with energy E = ħω reduces the mass of the box-clock system by m = E/c^2, which is on a scale. Einstein argued that knowledge of t and the change in weight provides an arbitrarily accurate measurement of both energy and time which may violate the Heisenberg uncertainty principle ΔEΔt~ħ

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Bohr realized that the weight of the device is made by the displacement of a scale in spacetime. The clock's new position in the gravity field of the Earth, or any other mass, will change the clock rate by gravitational time dilation as measured from some distant point the experimenter is located. The temporal metric term for a spherical gravity field is 1 - 2GM/rc^2, where a displacement by some δr means the change in the metric term is \simeq~(GM/c^2r^2)δr. Hence the clock's time interval T is measured to change by a factor

T-- >T sqrt{(1 - 2GM/c^2)δr/r^2} ~ T(1 - GMδr/r^2c^2),

so the clock appears to tick slower. This changes the time span the clock keeps the door on the box open to release a photon. Assume that the uncertainty in the momentum is given by the Δ p ~ ħ/Δr \lt TgΔm, where g = GM/r^2. Similarly the uncertainty in time is found as ΔT = (Tg/c^2)δr. From this ΔT > ħ/Δmc^2 is obtained and the Heisenberg uncertainty relation ΔTΔE > ħ. This demands a Fourier transformation between position and momentum, as well as time and energy.

This holds in some part to the quantum level with gravity, even if we do not fully understand quantum gravity. Consider the clock in Einstein's box as a black hole with mass m. The quantum periodicity of this black hole is given by some multiple of Planck masses. For a black hole of integer number n of Planck masses the time it takes a photon to travel across the event horizon is t ~ Gm/c^3 ~ nT_p, which are considered as the time intervals of the clock. The uncertainty in time the door to the box remains open is

ΔT ~ Tg/c(δr - GM/c^2),

as measured by a distant observer. Similarly the change in the energy is given by E_2/E_1 ~= sqrt{(1 - 2M/r_1)(1 - 2M/r_2)}, which gives an energy uncertainty of

ΔE ~ (ħ/T_1)g/c^2(δr - GM/c^2)^{-1}.

Consequently the Heisenberg uncertainty principle still holds Δ EΔT ~ ħ. Thus general relativity beyond the Newtonian limit preserves the Heisenberg uncertainty principle. It is interesting to note in the Newtonian limit this leads to a spread of frequencies Δω ~ sqrt{c^5/Għ}, which is the Planck frequency.

The uncertainty ΔE ~ ħ/Δt larger than the Planck mass gives an event horizon. The horizon has a radius R ~ 2GΔE/c^4, which is the uncertainty in the radial position ΔR associated with the energy fluctuation. Putting this together with the Planckian uncertainty in the Einstein box we then have

ΔrΔt ~ 2Għ/c^4 = L^2_{Planck}/c.

So this argument can be pushed to understand the nature of noncommutative coordinates in quantum gravity.

This complementarity means that fundamentally with quantum mechanics there is no meaning to space and time outside of the context of a measurement, or the choice of observation. QM has no contextuality of its own, and so any statement made about the spatial and temporal nature of the world is something which is determined by the choice of basis by the observer.

Quantum logic is interesting in some ways, but I don't think it really buys us that much. It is sort of a formal set theory way of doing what we already understand.

Cheers LC