Reply to Jack Semura and Todd Duncan, Entropy, Information, Deep Second Law Physics

Jack Semura and Todd Duncan discuss in their paper whether or not information is erased through entropy, and whether information could be recovered after it was erased.

The paper is located here (or search google for this title below):
The Deep Physics Behind the Second Law: Information and Energy As Independent Forms of Bookkeeping

What do they mean by "erase"? Indeed it seems to be an issue of Laynes Law here (arguments over the definitions of words) and what needs to be clarified is what they actually mean by "erase". Could this be similar to Stephen Hawking thinking that information is erased in black holes when in fact it is simply radiated (reconfigured) to a new form?

When you erase data on a hard drive, you are just scrambling the information into more scrambled information (the information seems to be conserved, but it just gets scrambled into entropy or hot particles radiating to the atmosphere, since the hard drive is surrounded by air).

I take issue with some of the references to recovering information, because you can still go into a low entropy state without recovering the information! An example is if you have a bookshelf of books sorted in alphabetic order. If we could rearrange the books into numeric (by bar code number) order, this would be a low entropy state but you would not be recovering any of the old information about alphabetical order. So in order to break the second law, one does not need to recover all the information from before (this would be a like a time machine) you could in fact just rearrange the information to be ordered in such a way that it was low entropy, but not the same low entropy configuration as before. A system can go into a low entropy state and be in a completely different configuration than before when it was in low entropy.

A JPEG or PNG black and white image could be a picture of a square composed of dots, and turn into a circle (just a rearrangement of the dots to a new shape), and this would be completely different information (configuration), but still low entropy. Energy input is usually required to rearrange something, so one would need to violate the second law by reconfiguring equilibrium into non equilibrium (hot and cold spots) automatically, with a force (like gravity or magnetism) without energy input - this is currently considered impossible (can you just add fixed structure/order to a system and violate the law without expending energy? Current orthodox thinking is no. Maybe right.)

They discuss in the article about whether or not second law violating proposals are recovering lost information... My criticism of this is that in order to violate the second law, one does not need to recover the old low entropy state (information configuration), one could instead simply obtain low entropy by re-configuring the information into a lower entropy state which is completely different than the original lower entropy state.

An example again would be if you had the word "read" and scrambled it into "aedr" which does not mean anything. If you rearrange "aedr" into "dear" you have now gone back to a low entropy state! But "dear" is not the same as "read". Both "read" and "dear" are low entropy configurations of information. They are both equally understandable words in english. So how did we get from "aedr" back to "dear"? The information was reconfigured. You are not recovering the original "read" word which was low entropy, you are instead creating a new low entropy state "dear". So you are not reversing time, you are instead going forward in time and creating a new low entropy situation without restoring to the original configuration. Something similar happens in evolution where a mutation (error) becomes beneficial by chance.

A corrupted hard drive with a poem on it may end up slightly improving parts of the poem with words being scrambled into other low entropy words, but it is unlikely. The difference in evolution is you have energy input from the sun: a bunch of animals that eat plants (from sun energy) run around with mutations and get eaten by other animals, while the beneficial mutations survive by the mutated animal not being eaten. However even though you have energy being added in evolution, you still can't ignore the fact that a error (mutation) did turn into a benefit, and order originated from disorder. So a second law violating device would have to be able to do this over and over again without energy input, whereas in evolution the sun continually inputs energy so more animals can run around killing off the badly mutated animals and keeping the beneficial mutated ones alive.

It usually takes energy in order to change "aedr" into "read" or "dear". When you change it to the correct word or the low entropy word, your brain is doing work and creating entropy. So in order to break the second law, someone needs to arrange "aedr" into "dear" or "read" without expending energy. The process needs to be automated without a maxwell thinking demon. However in the case of 2nd law energy devices (like Sheehan's diode or Brownian Motion Interference) we don't even need to arrange "aedr" back into "read", we could simply arrange a bunch of cold particles into a clump, and arrange hot particles into complete scatter.. one needs a hot and cold partition, separating hot and cold.

So sometimes analogies like the "aedr turning into dear" one, break down. Do we even need that much information about the system in order to break the second law? (related: container information theory). The only information we really need to worry about is making a clump of cold air, separate from a clump of hot air (automatically without expending energy), and then all of a sudden you have a perpetual motion device. There is no need to reconfigure the information exactly as it was before 10 seconds ago (you aren't reversing time) and there is no need to make the information extremely ordered into something like a Shakespeare book .... all you need to do is make a clump of hot air separate from a clump of cold air, and you have a temperature differential (easier said than done). Just because you make a clump of cold air (or section) doesn't mean that this air will be exactly the same configuration as it was 10 seconds ago before you broke the law - the information could be arranged very differently and still be low entropy!

Brownian motion is perpetual motion, precisely because microscopic temperature differentials exist.
"The truth of the second law is ... a statistical, not a mathematical, truth, for it depends on the fact that the bodies we deal with consist of millions of molecules... Hence the second law of thermodynamics is continually being violated, and that to a considerable extent, in any sufficiently small group of molecules belonging to a real body." -- James Clerk Maxwell
Are these second law violating microscopic events that cause brownian motion to rarely be ordered (say the pollen moved only leftward for 5 seconds), recovering lost information? No they are just reconfiguring the information to a new state. A brownian motion object moves randomly and becomes in a different information configuration over time. A bunch of random nano magnets, over time, due to brownian motion, will eventually clump back together automatically in a low entropy state without any energy input (second law paradox?). This is not recovering lost information as far as I know, it is just a reconfiguration of information? If nano magnets naturally clump together over time due to random brownian motion, this would not mean the nano magnets recovered the information of their previous state, since their previous state could have been millions of different things: originally they could have started out as a clump arranged differently than the new clump. Not all clumps are equal.

Another interesting idea is that if quantum mechanics really did have hidden variables (like a computer program that has state and a random number generator) and if this random number generator seed or encryption could be cracked, then one could predetermine what would happen in a system and predict exactly where a brownian motion particle is going to be next, and one could build a system so that you know ahead of time how to break the second law by literally predicting where the particle will be. You only have to know about it once, and can then violate the law over and over again since you can simply start the particle off at the same starting position with the same environment. It is unlikely that we would crack the code behind the universe, so I am putting this idea here only as a distraction.

However, my focus on this website is to come up with proposals that do not require cracking the code behind the random number generator that powers quantum mechanical "uncertainty" (if it's random number generator seed can be cracked, it's not "uncertain" but gives only the appearance of being uncertain to mere apes who can't break the encryption). Again this idea of cracking the code behind the universe is more of a distraction: my focus is on simple devices that could cause low entropy based on structure or geometry in the system (or something that forces nonequilibrium to occur). Cracking the code to the universe would require too much work, and may not be possible. If we could crack the code to the universe it would likely require a quantum computer (which may have to be as big as the universe itself, or not, depending on how recursion would work - could a quantum computer be recursively more powerful than the universe that contained that quantum computer - doubts galore).

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