1. ### I Does Decoherence get rid of all Quantumness?

The answer is no and even when decoherence occurs for Wigner's Friend in the lab, quantum coherence remains. Let's start with the paper that illustrates this. Assisted Macroscopic Quantumness CONT. https://arxiv.org/abs/1711.10498 Wow, I recently read this paper and the results are simply...
2. ### Claude Shannon "The Bit Player" movie free screening

This weekend (June 26-28) the IEEE Information Theory Society is showing a free screening of The Bit Player - a movie about Claude Shannon (the "father" of information theory) The website below has the link and password for Vimeo...
3. ### I Does information get lost by measurement?

If we consider quantum wavefunction-collapse, when we end up in a world-thread with a specific value of the measurement outcome, has information got lost?
4. ### I How does Classical Physics explain Quantum Entanglement?

As a Computer Programmer, it's hard to wrap my head around Quantum Entanglement and non locality being explained in the context of Classical Physics. In other words, if the universe at it's core is physical where does Quantum Entanglement fit within a physical picture of reality? There's been...
5. ### I Time Delay Information Transfer with Entangled Particles

Hello, my name is Jack and I'm a year 11 student in Australia. After listening to, and reading some information regarding quantum entanglement, I'm still a little unsure about the solution to a thought experiment: Let's say that I create a situation in which multiple pairs of particles are...
6. ### I "It from Bit" and the multiverse?

Did physicist John Archibald Wheeler propose the existence of multiple universes through his "It from Bit" or "Participatory Universe Principle" or "Law without Law and Pregeometry"? Is the multiverse related to Wheeler's ideas? I've been told that It can produce multiple universes, obviously...
7. ### A Irreversible processes. Heat equation, diffusion equation

Both the heat equation and the diffusion equation describe processes which are irreversible, because the equations have an odd time derivative. But how can these equations describe the real world when we know that all processes in nature are reversible, information is always conserved? But these...
8. ### B Is the Universe information?

Is the problem with interpretations of quantum mechanics that one can describe the universe consisting of "stuff" that exists ontologically in different but conflicting ways, so that the universe can really only be described informationally instead of ontologically? That is: does the universe...
9. ### I Uncertainty: balance of two aspects?

There are two aspects of uncertainty (a) how far different from the situation where all possibilities are of equal probability (b) how spread out the values are. In discussions about (Shannon) entropy and information, the first aspect is emphasized, whereas in discussions about the standard...
10. ### A Could information in a boundary be modified once encoded?

Could information in a boundary be modified once encoded in holographic principle? There are models of universes where holographic principle has a different correspondence (there is absolutely no reason to assume that this would hold true for all possible universes. You could have a universe...
11. ### A Information and successive measurments

Suppose you measure the spin of an electron along some axis, we get the result +1 with probability 0.5 and -1 with probability 0.5. The average information we receive is 1 bit of information. Now if we rotate our apparatus 90 degrees and make a new measurement, we will as before get the value +1...
12. ### Insights How to Better Define Information in Physics - Comments

Greg Bernhardt submitted a new PF Insights post How to Better Define Information in Physics Continue reading the Original PF Insights Post.

21. ### B What percentage of the universe do we know

Hello. First of all, I must say that I'm new to this forum, so I apologize if I'm posting in the wrong section. I'm a 17 year old with not that much knowledge about physics, so if what I'm talking about makes no sense or is completely stupid, just let me know. A couple of days ago I asked...
22. ### B Measurement and the creation/loss of information

If we measure, say, the polarisation of a photon, the polarisation state of the photon collapses along the eigenvector of the observable corresponding to the measurement. This may seem as a loss of information of the original polarisation (for it is now collapsed into another value). However...
23. ### A Information contained in minimum value of truncated distribution

Suppose that a given population is endowed with a pair of characteristics T and K. Let's think of these characteristics as random variables (T,K)∼BiNormal((μT,μS),(σT,σS),ρ) I observe the realisations of T for a sample consisting of those individuals with K<a, where the selection threshold a...
24. ### Help understanding Shannon entropy

Hi I'm having some trouble understanding Shannon entropy and its relation to "computer" bits (zeros and ones). Shannon entropy of a random variable is (assume b=2 so that we work in bits) and everywhere I've read says it is "the number of bits on the average required to describe the random...
25. ### I Is there anti-Information?

Is there any theory that says anti-information exists? If there is anti-matter, would that matter carry information to annihilate the regular matter's information saying its a certain type of matter and turn it into energy? Could anti-matter just be regular matter with anti-information.
26. ### The informational paradox of rectilinear motion

If the torsion of the straight line is undefined what happens with the information about the torsion? It is known (https://en.wikipedia.org/wiki/Quantum_no-deleting_theorem, http://van.physics.illinois.edu/qa/listing.php?id=24045) that the information conserved in a system can be nor created...
27. ### Presentation about Roger Bacon (rainbows)

I need to give a presentation about roger bacon (the guy who said that rainbows form at a 42 degree angle). It's hard to find information about his study of rainbows so if anyone knows something about it I'll be grateful.
28. ### How is information lost if nothing passes the event horizon?

Hi. From an outside observer's view, any object approaching the event horizon of a black hole appears to slow down and never quite pass through the horizon. So information about those objects can always be retrieved (if you correct for the redshift). So what actually is the information paradox...
29. ### Relationship between energy, information and dark energy

Hi. I have no significant pure physics or math education or work experience (retired corporate analyst) but I was wondering what experts here might think about the relations between energy, dark energy and information. My understanding is that dark energy is the expansion of space, with space...
30. ### EPR paradox and time of collapse

According to the EPR-paradox, if we have a pair of two entangled spin-1/2 fermions A and B and measure z-component of A, B collapses immediately as well(i'm using these letters for both particles and their observers). The 'canonical' solution is then to state that it is not possible to transfer...