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Steve Dufourny: on 5/28/20 at 22:10pm UTC, wrote Mr Crecraft, you could answer to all persons, you beleive that you are...

Jenny Wagner: on 5/19/20 at 18:33pm UTC, wrote Dear Harrison, since we do not know how long posting still works, I have...

Harrison Crecraft: on 5/18/20 at 11:06am UTC, wrote Hi Jenny, More great questions! Any meaningful discussion HAS TO start...

Jenny Wagner: on 5/17/20 at 20:45pm UTC, wrote Dear Harrison, thanks a lot for the further explanations! I agree that...

Harrison Crecraft: on 5/17/20 at 14:47pm UTC, wrote Hi Jenny, Thank you for your comment. You raise an excellent and...

Jenny Wagner: on 5/17/20 at 10:39am UTC, wrote Dear Dr. Crecraft, I followed your discussion with Dr. Petkov about his...

Michael Kewming: on 5/10/20 at 20:49pm UTC, wrote Hi Harrison, Thank you for a well-written essay. I almost entirely agree...

Steve Dufourny: on 5/2/20 at 18:18pm UTC, wrote Hi Peter, I d like to tell you an inportant thing that you could consider...


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Lorraine Ford: "1. Physics can’t tell you why the world ever moves, i.e. physics assumes..." in The Present State of...

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September 19, 2021

CATEGORY: Undecidability, Uncomputability, and Unpredictability Essay Contest (2019-2020) [back]
TOPIC: On the Decidability of Determinism and Time’s Arrow by Harrison Crecraft [refresh]
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Author Harrison Crecraft wrote on Feb. 13, 2020 @ 11:19 GMT
Essay Abstract

This essay’s contest description asks the question: Are there real consequences for physics — including quantum mechanics — of undecidability and non-computability? I conclude that the determinism and reversibility of physical reality is empirically undecidable. A conceptual model of physical reality, on the other hand, can logically decide the truth of fundamental determinism and reversibility, but only by assuming postulates that are, themselves, empirically unprovable. The prevailing conceptual models of physics assume that a system’s underlying (and unobservable) physical state is defined by perfect measurement, in the absence of thermal noise. Together with the deterministic laws of physics, this implies fundamental determinism and reversibility. The absence of thermal noise is an assumption based on extrapolation, however. It is not an observable fact. I consider an alternative conceptual model by defining perfect measurement from a system’s actual surroundings at a positive absolute temperature. This model, dissipative dynamics, implies fundamental randomness and irreversibility. Dissipative dynamics and the prevailing models are empirically consistent with observations, but consistency is not proof, and their contrasting interpretations clearly cannot both be true. The truth or falsity of a conceptual model cannot be decided by observations. The best we can do is to judge models by assessing the generality of their assumptions and on the reasonableness of their implications relative to observations. I argue that dissipative dynamics is more general, and its implications conform more directly to observations, compared to prevailing deterministic and reversible conceptual models.

Author Bio

Harrison Crecraft is retired from his career as a geologist and geochemist in the geothermal industry and geological consulting. He received his PhD in geology in 1984. At graduate school, he starting searching for foundational principles of physics to understand why open systems evolve toward greater organization and complexity. He pursued this side interest throughout his career and continues it into retirement.

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Joseph Maria Hoebe wrote on Feb. 13, 2020 @ 15:16 GMT
Thank you. Very nice essay.

The conclusion could be a bit more advantageous, as if you stopped because of just writing for the sake of the essay.

Since closed systems are conceptual systems, thermodynamics must be conceptual too. Hence the call for rewriting the concept on the base of interdependent systems.

I read also your essay "The Arrow of Functional Complexity".

I was pleasantly surprised by your models, cause they resembled, to me, something of one of my inventions. you can find it under:

all the best,

Jos Hoebe

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Author Harrison Crecraft replied on Feb. 13, 2020 @ 21:16 GMT
Thank you, Jos for the nice comments. I'm glad you looked at the arrow of functional complexity--figuring that out was my motivation for getting started on this venture many years (decades) ago. This contest and essay give me additional fodder for my argument on why we need to move beyond the Hamiltonian paradigm, which still has a hold over physics after nearly 200 years!

I looked at your Researchgate article. It looks interesting, but I need to spend more time on it to absorb it.

Best to you,

Harrison Crecraft

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Edwin Eugene Klingman wrote on Feb. 13, 2020 @ 22:51 GMT
Dear Harrison Crecraft,

Thank you for an excellent essay. I believe that your definitions of empirical versus conceptual models are superb, and I will probably quote you in my own essay, as they are extremely relevant to my topic.

I also found your treatment of Hamiltonian mechanics and thermodynamics quite interesting; my essay may have something to contribute to these arguments.

I very much appreciated your concluding analysis of Gödel's relevance to physical reality interpretations, which addresses the essay topic beautifully.

I wish you the best in this contest,

Edwin Eugene Klingman

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Author Harrison Crecraft replied on Feb. 14, 2020 @ 14:37 GMT
Wow! Thank you Edwin.

I'm glad you found some useful ideas.

I look forward to seeing your essay.


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Edwin Eugene Klingman replied on Apr. 5, 2020 @ 19:13 GMT
Hi Harrison,

My essay is finally up. I hope you find it interesting.

Deciding on the nature of time and space

My best regards,

Edwin Eugene Klingman

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Jonathan J. Dickau wrote on Feb. 14, 2020 @ 00:40 GMT
We have a few points of agreement...

I like to think of thermodynamic entropy in terms of spreading, which makes randomness an effect of entropy instead of its manifestation, but I guess you covered that in your Hamiltonian model discussion. As with Ed; I'm glad you worked that part up, to show things from a 'total energy' view.

A lot of people get hung up on Lagrangian analysis without ever realizing Hamiltonians are not just equivalent but sometimes advantageous to use. And I like the connection with MWI that implies, which explains some of the views of Dieter Zeh in decoherence theory. A different point of view from the norm though. Perhaps what is needed.

My research appears to show that we should view the entire universe as a dissipative system, rather than imagining all symmetries are absolute. I think what's real is global asymmetry with local symmetries that extend out to a very large neighborhood - perhaps the Hubble volume - but are ultimately broken and lead to a cold dark end, or a new cycle.

More later,


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Author Harrison Crecraft replied on Feb. 14, 2020 @ 14:47 GMT
Thank you for your comments, Jonathan.

I am in complete agreement that the universe is best modeled as a dissipative system. This is discussed in the two essays referenced. As noted in "time reinvented," implication #4, the declining ambient temperature of the universe, currently at 2.7 K, has significant implications on its evolution.


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Lachlan Cresswell wrote on Feb. 25, 2020 @ 01:56 GMT
Hi Harrison,

Nice essay. The conflict between empirical irreversibility and physical reversibility as pertaining to the entropy and the arrow of time was studied by Josef Loschmidt and is known as Loschmidt’s paradox, which I cover in my essay. I believe this paradox can be used to show that wave particle duality is implausible. I think Maxwellian electromagnetic radiation is an example of the dissipative dynamical system you mention in your essay. I like the idea of a complex time embodying reference time, thermodynamic time and mechanical time. I argue elsewhere that the reference time is actually cosmological time.

All the best

Lachlan Cresswell

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Author Harrison Crecraft replied on Feb. 26, 2020 @ 17:51 GMT
Hi Lachlan,

Thank you for your comment. In regard to Loschmidt’s paradox, you ask in your essay “what breaks the time-reversibility of classical mechanics?” I agree that electromagnetic radiation is an important illustration of irreversibility. However, the mere asymmetry of electromagnetic propagation from a point source does not necessarily mean fundamental irreversibility.

The expansion of a gas into a vacuum is undeniably asymmetric in time, but most conceptual models of physics assume that it is reversible, in principle. If motions were reversed, expansion would reverse, and no laws of mechanics would be violated. It may be astronomically unlikely, and this breaks the symmetry of time, but whether it is fundamentally irreversible is a deeper question and one that is generally ignored.

Fundamental determinism and reversibility are deeply ingrained in conceptual models of physical reality, and it is rarely questioned. As I argue in my essay, however, fundamental determinism and reversibility are not empirically provable, and randomness and irreversibility are, in fact, compatible with observations and with the deterministic laws of physics. The reason is that determinism means a precise cause maps to a precise effect, but with fundamental randomness, there is no precise initial cause. Deterministic evolution of an initial cause or state with fundamental but empirically unresolvable randomness can be irreversibly amplified to macroscopically random outcomes.

Assuming fundamental determinism and reversibility requires extraordinary, and unnecessary, machinations to explain empirical irreversibility and the spontaneous organization of complexity within open systems (e.g. the origin and evolution of life). An absolute-zero ambient temperature is unobtainable, and the absence of fundamental thermal randomness assumed by most conceptual models of physics is an idealization that simply does not reflect physical reality.

Harrison Crecraft

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Flavio Del Santo wrote on Mar. 11, 2020 @ 16:55 GMT
Dear Harrison (id I may),

I fully agree with you that “determinism is empirically undecidable by observations”, as I also voice in my essay, in the conclusions. However, I also try to argue why determinism seems less realistic than indeterminism, even in classical physics. So, while empirically equivalent, there cuould be phiòlosophical arguments that hint at one direction. You might like to have a look at that and we can then maybe discuss this further

All the best,


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Author Harrison Crecraft replied on Mar. 11, 2020 @ 17:47 GMT
I look forward to reading your essay.

To be clear, I argue that fundamental determinism may be consistent with observations, but it leads to unreasonable conclusions. Fundamental indeterminism is also consistent with observations, but it leads to highly plausible conclusions. It allows extending physics from states to dissipative systems, and it allows for an explanation of spontaneous evolution of complexity. The spontaneous evolution of complexity is consistent with observations, but it is incompatible with determinism.

I believe empirical observations clearly favor an interpretation of fundamental indeterminism, even in classical mechanics.

I will read and comment on your article.


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Member Klaas Landsman wrote on Apr. 13, 2020 @ 17:01 GMT
Dear Harrison,

Thanks for this beautiful and well-argued essay. I agree with the undecidability of determinism versus randomness but disagree about what you say about the irrelevance of Gödel's theorems - how could I agree with you given my own essay in this contest! Fortunately, your reasoning rather seems to confirm the relevance of his incompleteness theorems, and if you had ended your essay saying this, it would have been just as natural. There is a long tradition (going back to Daneri, Loinger, Prosperi, early 1960s or even earlier) of relating randomness of measurement outcomes in quantum mechanics to metastability, but this tradition missed the importance of the classical or macroscopic limit of QM in enhancing the importance of external perturbations, which destabilize a metastable state and lead to collapse (cf. your endnote 2). See my 2017 Open Access Book Foundations of Quantum Theory, available at

Best wishes, Klaas Landsman

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Author Harrison Crecraft replied on Apr. 15, 2020 @ 11:51 GMT
Thank you Klaas, I appreciate your kind comments. And thank you for the pointers to additional research. I look forward to reviewing your book on quantum foundations.


Harrison Crecraft

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Peter Jackson wrote on Apr. 14, 2020 @ 17:55 GMT

Great essay, spot on topic and nicely argued. I also conclude the same as you, but I've identified a very specific mechanistic and largely deterministic sequence producing the irreversibly and divergence, or "dissipation" in your terms. I'm interested if you think it compatible;

It's a shame you missed last years contest as I derived this in detail there, but I touch on it...

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Author Harrison Crecraft replied on Apr. 15, 2020 @ 12:33 GMT
Hi Peter,

Good to hear from you. Thank you for your kind comments. I discovered the FXQI site just 5 days before the last contest ended, and then had to wait nearly two years for this next contest. You might recall that you and I exchanged comments during a discussion I initiated several years ago on quantum interpretations on the APS LinkedIn group.

In my conceptual model, which is further described in the two Medium essays I reference, classicality of measurement is largely restored, with the qualification that perfect reversible measurement is only definable with respect to a system’s actual physical context, and this includes a positive ambient temperature. This introduces fundamental randomness in transitions of a metastable state to a more stable state. However, between transitions, a metastable particle’s contextual state can be reversibly and non-statistically measured. If measurements are conducted at a basis temperature lower than the system’s ambient temperature, however, measurements are irreversible, and the results are statistical. I see no fundamental incompatibility with the measurements as you describe. The dissipation is a consequence of irreversible and random transformation of the particle from its pre-measurement context at its ambient temperature to a post-measurement context at lower basis temperature of measurement. I have several manuscripts that describe this in much greater detail. I’ve had journals review them, but so far not published.

Best regards, Harrison Crecraft

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Peter Jackson replied on May. 1, 2020 @ 08:51 GMT

That description sounds correct, maybe just incomplete, and indeed we've shown polarisation changes on interaction, and indeed if the medium particles are in lateral motion the optical axis is also rotated, giving the 'kinetic reverse refraction' effect and finally solving the stellar aberration problem!

I've had papers published on those, one on arXiv, but even then it can mean nothing as they're entirely ignored! But we must persist. Many such areas are referred in my essay(s).

I look forward to your comments on mine this year.

Very best.


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Steve Dufourny replied on May. 2, 2020 @ 18:18 GMT
Hi Peter,

I d like to tell you an inportant thing that you could consider for this universal balance and my 3D spheres, we try to capture in Words our ideas , like we formalise them in maths and try to prove our assumptions. Like you know , I repeat the generality ,I work about my theory of spherisation, an optimisation of the universal sphere or future sphere with quantum 3D spheres and...

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Steve Dufourny wrote on Apr. 14, 2020 @ 18:44 GMT
Hello Professor Crecraft,

Congratulations for your essay, I liked a lot your approach. I see that you are PhD In geology, I was in geology I have stopped in second in belgium due to a coma due to a big epileptic crisis, my professor was Mr Overlau from the FNDP in belgium, Namur the Town, I like this geoology, I have ranked the minerals , the animals, vegetals, biology, Chemistry, physics , maths also, it is like in ranking even that I found my theory of spherisation and the 3D spheres like foundamantal objects , I wish you all the best in this Contest, a very relevant general essay,

best Regards

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Michael muteru wrote on Apr. 30, 2020 @ 10:37 GMT
hi crecraft. you beautifully crafted essay raises core questions on the emergence of empirical parameters.Observation or measure....which of the two leads to the other. do we measure before we observe,or do we observe before we measure? I have done something on how all of science is guided by anthropic reason here- all the Best in the essay.

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Michael James Kewming wrote on May. 10, 2020 @ 20:49 GMT
Hi Harrison,

Thank you for a well-written essay. I almost entirely agree with your essay! In fact, many of the topics and themes we cover reach the same conclusions, that is, Godel and Turing's theorems do not bear any significance on physics as they cannot be implemented in a physical environment; they must contend with the laws of thermodynamics.

One point I had a question maybe an additional clarification

``Physics is virtually united that a precise cause yields a unique and precise effect. This is the doctrine of determinism.''

I would add that deterministic theories are ones that do not increase the overall entropy of the system and are thus time-reversible. As you point out quantum measurement is intrinsically indeterministic, soley because it is irreversible.

I would love to get your feedback on my essay. We both reached similar conclusions, however we took slightly different trajectories to get there.



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Jenny Wagner wrote on May. 17, 2020 @ 10:39 GMT
Dear Dr. Crecraft,

I followed your discussion with Dr. Petkov about his essay with great interest and therefore read your essay as well. Thank you very much for this inspiring view on determinism and measurement problem(s)!

What I found highly interesting is your DDCM, which generally shows the advantages of describing systems from the perspective of their "background"/reference surroundings. I have some question concerning this splitting:

- can we say that thermal randomness occurs due to the non-perfect split into "system" and "surrounding", because the system always interacts with the environment (unless both are in equilibrium with each other)?

- if the latter point is the origin of thermal randomness, is it really objective reality because, it may be possible that different observers can take different choices how they split into "system" and "environment"?

- concerning the very last part about Goedel's undecidability, I think you are right, even if we can build a perfectly decidable theory on the basis of logic, it may still leave some freedom in the physical interpretation. If you are interested in a cosmic example, have a look at my essay. I think we are on the same page that we cannot know what reality does between two measurements.

With best wishes, success and luck for the contest,

Jenny Wagner

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Author Harrison Crecraft replied on May. 17, 2020 @ 14:47 GMT
Hi Jenny,

Thank you for your comment. You raise an excellent and fundamental question, which I paraphrase: if we can choose how to split a system from its surroundings, and if physical reality is contextually defined with respect to its surroundings, is it really objective?

When we define a boundary separating a system from its surroundings, we choose the system’s surroundings. When we conduct an experiment, the experimental apparatus defines the systems ambient surroundings at measurement. So we are choosing the system’s surroundings (and inertial reference). This is why a contextual physical reality is so difficult to accept. But the ambient “surroundings” for the universe as a whole, or more properly its ambient microwave radiation background, is objectively defined and any subsystem can be defined with respect to that ambient background. In a contextual reality, the context is a given and part of the system’s definition; once the system’s context is given, the system’s description is objective and complete (in the limit of perfect measurement—see Fig 1).

Thermal randomness is also a very tricky concept. Thermal randomness implicitly assumes random fluctuations of precise coordinates, but precise coordinates are definable only with respect to an assumed ambient temperature of absolute zero. As long as a system interacts with its actual surroundings, it exists as a contextual state, whether it is an equilibrium or metastable state. States evolve deterministically and there are no random fluctuations. Randomness only comes in during irreversible transition from one metastable state to another more stable (higher entropy) state. During an irreversible transition, the system is not interacting with its surroundings. This is the basis for the quantum zeno effect.


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Jenny Wagner replied on May. 17, 2020 @ 20:45 GMT
Dear Harrison,

thanks a lot for the further explanations!

I agree that fixing the background gives a definition of the system for one observer, so that this observer can probe the system and obtain his results. But my question goes further (or I did not fully get your answer): assume observer A uses the cosmic microwave background temperature at his position as background temperature and measures the temperature of a system next to him. Now let observer B do exactly the same, but with the difference that the microwave background temperature at his position is not the same as that at A's place. Both measure the temperature of the same system but with their respective background. So both need to agree on a common reference (i.e. a background to each other, if you like) to be able to compare their measurements, right? Hence the split into background and system is not unique. So does every observer have their own contextual reality or is there a common one after they agree on a reference between each other? Or is the problem solved by stating that each observer only has his own knowledge about the system in the reference frame he chooses and does not know whether an objective, absolute reference frame exists?

Thank you as well for the further comments on thermal randomness. Guess I need to think a bit longer about that!

Best regards,


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Author Harrison Crecraft replied on May. 18, 2020 @ 11:06 GMT
Hi Jenny,

More great questions!

Any meaningful discussion HAS TO start with mutually agreed assumptions. Here are the assumptions of state for the Dissipative Conceptual Model:

Postulate 1: No system has surroundings at absolute zero temperature and no system can be perfectly insulated from its ambient surroundings.

Definition 1: The ambient microstate for a system...

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Steve Dufourny wrote on May. 28, 2020 @ 22:10 GMT
Mr Crecraft, you could answer to all persons, you beleive that you are special or that you sort the persons to answer ??? for me you are a common thinker, nothing of special, sorry but I am frank, I dislike these comportments, you have not answered to 3 persons, why ? this Vanity and lack of consciousness begin to irritate me a lot to be frank

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