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What is entropy? A measure of just how little we know

quantamagazine.org

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Re: What is entropy? A measure of just how little we know

#11

Post by ChaitanyaSai »

Lovely article. The subjective nature of entropy and information immediately makes me think of the IIT theory (integrated information theory) of consciousness and its foundational futility. Information cannot be discussed without perspective. Someone has to define the states. A die have 6 states only to us humans. What about an ant that's likely to have the die land on it? Bringing the observer back into discussions of information is fascinating because it then begs the question: How is the observer put together? And how does a perspective, an I, emerge in a multi-trillion-cell entity? For those interested in this detour, you might like reading this and our book (mentioned in there)

https://saigaddam.medium.com/consciousness-is-a-consensus-me...

Re: What is entropy? A measure of just how little we know

#12

Post by srean »

guerrilla wrote: post #7
pndy wrote: post #3

http://www.thelastquestion.net/ - in case someone missed it somehow

This is my favorite Isaac Asimov story and the reason I started reading him.

For all who haven't, please read the other two as well.

Last Answer

Nightfall

Re: What is entropy? A measure of just how little we know

#13

Post by tsoukase »

My perspective:

1) entropy is a mathematical concept. Physics apply it, like any other mathematical one

2) math entropy does not change, everything is reversible, as it is based on known quantities

3) entropy measures how far we are from perfectly knowing a system

4) logarithm is chosen to measure entropy because of its convenient properties, not because of any deeper law. It could be a sum, a product etc

5) the Second thermodynamic law is a tautology: "every system tends to higher entropy state because it is more common" becomes "the more common is the more common"

Re: What is entropy? A measure of just how little we know

#16

Post by gyomu »

openrisk wrote: post #14

Is there a specific name for the art and craft of presenting a topic online (as a web page) using a flow of text interspersed with interactive activities? Whatever the name of this approach, quantamagazine is definitely good at it!

Some people have coined the term explorable explanation/explorables

https://explorabl.es/

https://en.wikipedia.org/wiki/Explorable_explanation

Re: What is entropy? A measure of just how little we know

#17

Post by TheSpiceIsLife »

openrisk wrote: post #14

Is there a specific name for the art and craft of presenting a topic online (as a web page) using a flow of text interspersed with interactive activities? Whatever the name of this approach, quantamagazine is definitely good at it!

Multimedia?

https://en.m.wikipedia.org/wiki/Multimedia

Multimedia refers to the integration of multiple forms of content such as text, audio, images, video, and interactive elements into a single digital platform or application.

Re: What is entropy? A measure of just how little we know

#18

Post by pndy »

srean wrote: post #12
guerrilla wrote: post #7

Earlier quoted context omitted.

This is my favorite Isaac Asimov story and the reason I started reading him.

For all who haven't, please read the other two as well. Last Answer Nightfall

Gotta mention that Nightfall exists as both Asimov's short story and a novel he co-wrote with Robert Silverberg nearly 50 years later

Re: What is entropy? A measure of just how little we know

#19

Post by inshard »

Fails to mention Heisenberg uncertainty, which in my opinion is a theoretical ceiling to this approach. Also it needs to account for cost of compute relative potential useful work from these quantum engines. If the energy cost of compute exceeds potential useful work, then it’s still net negative (or useless work). Finally there’s the question of hidden patterns and the spectrum of randomness. Some systems are more random than others. The potential for useful work within a reasonable energy cost of compute will decline when we travel down the spectrum of randomness. Systems which are at maximal Heisenberg uncertainty, I.e. particles are not entangled, and have no correlation with a superstructure of other entangled particles, will not hold any further improvement to knowledge and thus zero potential work. This is the ultimate entropy of the local and macro system. Probably also the cause of certain violation of conservation of energy principles, such as dark energy.

Re: What is entropy? A measure of just how little we know

#20

Post by daoboy »

The interactive graphic that tries to show entropy is subjective doesn't sit right for me.

They fail to properly define the macrostate of the system under consideration, then show two different observed entropies for two different macrostates (Colors for Alice and Shapes for Bob).

That doesn't show entropy is subjective, it shows that defining the system is subjective. The same two macrostates would still have the same entropy

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