Could we calculate the number of Planck flops in a human lifetime?

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Discussion Overview

The discussion revolves around the concept of calculating the number of Planck flops, or commutator operations, that could occur in a human lifetime. Participants explore the implications of commutators in quantum mechanics, particularly in relation to position and momentum, and how these might relate to the quantification of decisions and actions over time.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant suggests that it is possible to calculate the number of Planck flops by considering a person's position and momentum over time, linking this to the concept of commutators and energy loss.
  • Another participant expresses uncertainty about their understanding of commutators, questioning whether they represent physical quantities related to energy and information.
  • A participant asserts that the commutator of position and momentum is non-zero, indicating that these quantities cannot be simultaneously measured with accuracy.
  • There is a discussion about whether choices made in measuring positions can be equated to bits of energy, as suggested by the commutator's role.
  • Some participants mention Planck's constant as a quantum of action but note that its interpretation can be informal and debated.
  • References to literature, including Reif's work on statistical mechanics and various papers discussing the implications of Planck's constant, are provided to support different viewpoints.
  • One participant acknowledges their confusion and expresses a desire for clarity regarding their understanding of Planck's constant and its implications.

Areas of Agreement / Disagreement

Participants express a range of views on the interpretation of commutators and Planck's constant, with no consensus reached on the implications or calculations proposed. Uncertainty and differing interpretations are evident throughout the discussion.

Contextual Notes

Some claims rely on informal interpretations of Planck's constant and its role in quantum mechanics, and there are unresolved questions regarding the fundamental discreteness implied by Planck units.

Jimster41
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just finished Susskind's QM. Definitely blew my mind. Can't stop wondering about commutators. Trying synthesize and remember with self quiz I can't self grade.

Super quiz: Could one in principle calculate the number of Planck flops (commutaor operations or bits) in a human lifetime?

My answer: Sure, the Planck unit is the quanta of action. If one were just to consider the position-momentum basis (to keep it simple), and assume a person is at all proper seconds "located" (because wherever you go there you are), and assume that a person is always a set number of massive quanta (surface area*kg) you could calculate how many non-commutative decisions were made to localize their position in space over some proper time interval - in other words how many [x,p] plank-sized commutator bits were left behind as "lost energy", or added as "einselections" (depending on your preference).
 
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I wasn't trying to make trouble. This was the really question I had after understanding (I thought) what commutators do. So I misunderstood completely?? I thought I understood that they are physical, and represent the bit of energy and information that comes out of, or must be supplied to the non-commuative congugate pair of degrees of freedom called position and momentum, if you want to say some real thing "is somewhere called x".

So that's just totally wrong, or not even understandable to anyone?

I thought the energy information relation was sort of settled by Shannon or somebody, but maybe I was wrong about that. This paper looks pretty recent.

http://arxiv.org/abs/1009.5287
Information heat engine: converting information to energy by feedback control
Authors:https://www.physicsforums.com/find/cond-mat/1/au:+Toyabe_S/0/1/0/all/0/1 , https://www.physicsforums.com/find/cond-mat/1/au:+Sagawa_T/0/1/0/all/0/1 , https://www.physicsforums.com/find/cond-mat/1/au:+Ueda_M/0/1/0/all/0/1 , https://www.physicsforums.com/find/cond-mat/1/au:+Muneyuki_E/0/1/0/all/0/1 , https://www.physicsforums.com/find/cond-mat/1/au:+Sano_M/0/1/0/all/0/1
(Submitted on 27 Sep 2010 (https://www.physicsforums.com/abs/1009.5287v1 ), last revised 29 Sep 2010 (this version, v2))
Abstract: In 1929, Leo Szilard invented a feedback protocol in which a hypothetical intelligence called Maxwell's demon pumps heat from an isothermal environment and transduces it to work. After an intense controversy that lasted over eighty years; it was finally clarified that the demon's role does not contradict the second law of thermodynamics, implying that we can convert information to free energy in principle. Nevertheless, experimental demonstration of this information-to-energy conversion has been elusive. Here, we demonstrate that a nonequilibrium feedback manipulation of a Brownian particle based on information about its location achieves a Szilard-type information-energy conversion. Under real-time feedback control, the particle climbs up a spiral-stairs-like potential exerted by an electric field and obtains free energy larger than the amount of work performed on it. This enables us to verify the generalized Jarzynski equality, or a new fundamental principle of "information-heat engine" which converts information to energy by feedback control.
 
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The commutator of position and momentum is not zero. This means the position and momentum of an arbitrary unknown state cannot be simultaneously accurately measured.
 
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Yes, thanks. (honestly, thanks for answering) That part I got from awesome Dr. Susskind.

And so to say a set of locations was identified over some history (just say you chose to claim that) requires that a set of choices were made specifying which one was measured. Each of those choices is a bit, which is of energy equal to the commutator (the quanta of action)?

Or no?

I just tried to engage you and Bhobba over on the long "What's surprising" thread. Sorry, these things are related to me.

If I don't make sense, that's fine, I understand. It's a problem. I can only try harder. If I do make sense but I'm wrong that's okay too. Either would be better than not knowing which it is.
 
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Plack's constant is the quantum of action, but it's an informal concept.
 
So I am clearly jumping to conclusions. At the end of Susskud there, I was thinking I finally understood the meaning and implications of Planck's constant better - as a component of evolution in time . But I guess not.

@bhobba. I don't believe you.
 
You could look up Reif's Fundamentals of Statistical and Thermal Physics
https://www.amazon.com/dp/1577666127/?tag=pfamazon01-20

I'm not sure I agree with Reif's presentation of statistical mechanics, but I think he does present Planck's constant as the volume of action. You can also find a description of this way of thinking in http://arxiv.org/abs/1501.04463 and http://hyperphysics.phy-astr.gsu.edu/hbase/quantum/phase.html.

The idea that it describes a minimum "something" also shows up in the Planck length, Planck time etc in quantum gravity. However, whether this implies a fundamental discreteness is still unknown. http://backreaction.blogspot.com/2015/08/dear-dr-bee-why-do-some-people-assume.html
 
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