Is information physical?

Comments

4 responses to “Is information physical?”

1. 

   December 5, 2025

   Philip Rey

   Dear Fedde,

   in your post on information you assume something you never actually show: that “information is about something physical but is not itself physical.” That sounds reasonable only as long as we don’t ask what this could mean inside the actual formalisms we use.
   1. You say “information” – but which one, exactly?
   You lump together, implicitly:
   Shannon information H(X),
   quantum information (von Neumann entropy S(\rho)),
   algorithmic information (Kolmogorov complexity).
   The sentence “information requires a carrier” is, at that level, almost trivial – about as deep as saying “a vector requires a linear space.” It is not yet a metaphysical thesis, just a technical truism.
   2. Where the asymmetry really shows up (MaxEnt)
   You write that information needs a physical carrier, and every physical thing carries information – so there is supposedly no reason to treat one as more fundamental. But in a number of central places in physics, it is precisely the informational structure that selects the admissible physical states:
   in Jaynes-style MaxEnt statistical mechanics, informational constraints (moments, averages) fix the maximum-entropy distribution; the carrier is secondary to the information structure,
   in quantum mechanics and QFT we work with density matrices, correlators, and functionals; these informational objects are what do the predictive work, not some imagined “little lumps of matter” underneath.
   So the natural question you avoid is: why should the carrier be considered fundamental, and not the informational structure that actually appears in the theory?
   3. Your key slogan doesn’t decide anything

   The claim
   “Information without a physical carrier is meaningless”

   is logically mirrored by the claim

   “Something physical, considered independently of any possible information about it, is equally meaningless.”

   You yourself invoke Quine and the erosion of the analytic/synthetic distinction. In a very similar spirit one can say: the network of informational structures and physical states forms a single package – and the choice of which description we call “primary” is an interpretive decision, not a dictate of experiment.
   4. A serious question
   If you want to keep insisting that “information is not physical,” then either
   show where, concretely, models that treat information (correlations, entropies, MaxEnt constraints) as primitive actually break down,
   or acknowledge that this is largely a linguistic/metaphorical preference rather than a thesis that can be cleanly pitted against current physical practice.

   You post provocative, thought-provoking texts on your blog, but in Foundations of Physics, which you edit, the journal is dull and almost septic in this respect.

   Why?

   Best,
   Philip Rey

   Loading…

   Reply
   1. 

      December 5, 2025

      fbenedictus

      Dear Philip,

      Thanks for your questions! I think your points go to the heart of the matter: physics gives us no unambiguous answer to the question in the title of my post.

      Regards,
      Fedde

      Loading…

      Reply
   2. 

      December 5, 2025

      Anonymous

      Dear Fedde,

      thank you for your reply and for your honesty in saying that physics gives us no unambiguous answer here. I’m deeply drawn to the way you write about these questions on your blog. There is a kind of intellectual grace there that reminds me of the early 20th century debates especially the 1905–1916 atmosphere around Einstein.

      You wrote a book about Einstein, so you probably feel exactly what I have in mind: most likely, the main character of that book would not make it through the formal filters of today’s journals. I try to keep this in mind, toutes proportions gardées, when I compare that early phase of physics with the present one and what is considered an “admissible” question today.

      I had a bad feeling you might not reply at all, and you proved me wrong. I’m genuinely grateful for that.

      Best wishes,
      Philip

      Loading…

      Reply
2. 

   September 1, 2025

   Jody Geiger

   This is a great age-old question that to date there has been little progress on, but we should have. First, our notion of observed length, mass and time (in this case with emphasis on mass as a carrier) is well described by SR and GR. Of notable example, SR can be presented as a kinematic relation between the observer and the ‘mass’. Thus, there is precedent in the publication record that the ‘carrier’ is not absolute and in fact is a function of the kinematics.

   The nature of the ‘carrier’ becomes more at issue when we consider EM. For one, the notion of time with respect to EM as a ‘carrier’ is not physically significant, as elapsed time must be marked to zero relative to the observer. Without elapsed time, how can you have a ‘carrier’ event, which then supports a process that conveys properties beyond those of the ‘photon’ itself.

   Your question can then be refined. What is the difference between observational information and kinematic information? There are cases where there is no difference and as all of existing SR and GR stand on these principles, it follows that some portion of ‘carrier’ information is a function of kinematic relationships. There are a handful of explicit expressions in the field of Measurement Quantization (MQ) that shed further light on this relation. I will call attention to one.

   MQ uses the expanding frame of the universe to resolve quantum accurate versions of the Planck units and demonstrates their physical significance by measure of the Planck momentum. Importantly, MQ also demonstrates with a 7.56-sigma that mass and the associated gravitational curvature are correlated to an upper fundamental mass count bound (the Planck frequency) … this is all published in Q2 journals (See ‘Measurement Quantization’ in the Intl. J. Geom. Methods Mod. Phys.). That is, an upper count bound per increment of elapsed time places an upper count of fundamental units of mass that can be observed. The gravitation associated with that count defines one component of the phenomenon of dark matter. (See ‘Measurement Quantization Describes Galactic Rotational Velocities, Obviates Dark Matter Conjecture’). This doesn’t mean the observer cannot observe infinite mass over elapsed time, but one will find that the gravitation associated with a mass count above the Planck frequency will is strictly bounded and in the noted paper we demonstrate consistency with that description with a standard deviation of 1.394 km/s Mpc.

   Now, if we are to maintain the argument that mass is a carrier, then regardless of MQ or classical theory, how is it that given larger and larger galaxies, that the addition of more and more mass ‘carrier’s does not demonstrate increasing gravitational curvature. We have a clear physical breakdown of this relation. With this, we sufficiently must agree, that the notion of a ‘carrier’ does not accurately describe all observed phenomena. The relation of observed events between the observer and the mass is shown in specific cases to be kinematic, and in some cases to have no relation to the total count of mass ‘carriers’. We can then safely conclude that the notion of a ‘carrier’ does not define or identify the foundations of physical theory.

   Whether information alone is a replacement is debatable, but what we can say is that the notion of a ‘carrier’ is not physically sufficient to describe the entire physical regime.

   Jody Geiger

   Loading…

   Reply