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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

#21

Post by openrisk »

TheSpiceIsLife wrote: post #17
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.

Multimedia is fairly general, so it includes this but also much more.

Including video in particular tends to highjack the experience (you switch mode), whereas interactive elements that you explore as you keep reading feel more integrated.

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

#22

Post by openrisk »

gyomu wrote: post #16
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

aah, this is nailing it. It helps to differentiate from game-like experiences and special purpose apps.

Another interesting term from the wiki link is "active essays":

> The related term "active essays" was used by Alan Kay to refer to text-based explorable explanations

But I don't know if by text-based he meant strictly no visuals. Like just ASCII art? :-)

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

#26

Post by plank »

Interesting to read this, 27 years after my PhD* (theoretical physics), in which I did compare the view WITH and the view WITHOUT ‘unknowns’ causing entropy as a driver.

* My PhD was about how to treat a (quantum mechanical) system inside a cavity: a cavity with one perfect mirror and one 99.999999% perfect mirror. The (one dimensional) universe was made whole by another perfect mirror at the other side of the non-perfect mirror (in ASCII art:

[100%] —l— [100-epsilon] ——L——— [100%]

With L >> l. The ‘whole universe’ solution was simple (using standard quantum mechanics techniques), the ‘lossy’ ‘small universe’ was not. But they needed to be the same (physically). Thus using the exact solution for the ‘complete’ (l+L) universe and comparing it to possible ‘small’ (l) universe models in which some non-linear term accounted for loss. The connection between how a lossy system (in which entropy exists/is a driving ‘force’) and a losless system (in which everything is conserved) is thus not a new insight;-0

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

#27

Post by lizzas »

bubblyworld wrote: post #9
niemandhier wrote: post #5

Earlier quoted context omitted.

In physics the requirement for a valid changing the frame of reference is, that the laws of physics transform according to the transformation. Every observer should discover the same fundamental laws when performing experiments and using the scientific method. To stay in your analogy, saying 5 and 6 are the same would only work if the rules of the game you play could transform in such a way that an observer making a…

I think you may have misunderstood the OP's point - the entropy you calculate for a system depends on how you factor the system into micro and macro states. This doesn't really have anything to do with changes of reference frame - in practice it's more about limitations on the kinds of measurements you can make of the system. (you can't measure the individual states of all the particles in a body of gas, for instance…

Can we take the anthropic out of this? I reckon it'll make things easier.

Instead of me knowing, do other physical objects get affected. I might get anemsia and forget what the dots on a dice mean and say they are all the same: all dotty!

Imagine each hydrogen atom has a hidden guid but this is undetectable and has no effect on anything else. This is a secret from the rest of physics!

I guess!!! (Armchair pondering!) that that guid cannot be taken into account for entropy changes. At least from any practical standpoint.

You could imagine each atom having a guid and come up with a scheme to hash the atom based on where it came from ... but is that info really there and if so does it affect anything physically beyond that atoms current state (as defined by stuff that affects other stuff).

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

#28

Post by bubblyworld »

lizzas wrote: post #27
bubblyworld wrote: post #9

Earlier quoted context omitted.

I think you may have misunderstood the OP's point - the entropy you calculate for a system depends on how you factor the system into micro and macro states. This doesn't really have anything to do with changes of reference frame - in practice it's more about limitations on the kinds of measurements you can make of the system. (you can't measure the individual states of all the particles in a body of gas, for instance…

Can we take the anthropic out of this? I reckon it'll make things easier. Instead of me knowing, do other physical objects get affected. I might get anemsia and forget what the dots on a dice mean and say they are all the same: all dotty! Imagine each hydrogen atom has a hidden guid but this is undetectable and has no effect on anything else. This is a secret from the rest of physics! I guess!!! (Armchair pondering!)…

What anthropic do you mean? I'm describing properties of models, not people. Physics (probably) doesn't care what you "know".

On the guid idea - fundamental particles are indistinguishable from one another in quantum mechanics, so they don't have anything like a guid even in principle. There is no experiment you could perform on an electron to determine whether it had been swapped out for a "different" one, for instance.

Maybe I'm missing your point though?

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

#29

Post by lizzas »

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.

This will be my favorite Issac Asimov story and the reason I will start reading him

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

#30

Post by lizzas »

bubblyworld wrote: post #28
lizzas wrote: post #27

Earlier quoted context omitted.

Can we take the anthropic out of this? I reckon it'll make things easier. Instead of me knowing, do other physical objects get affected. I might get anemsia and forget what the dots on a dice mean and say they are all the same: all dotty! Imagine each hydrogen atom has a hidden guid but this is undetectable and has no effect on anything else. This is a secret from the rest of physics! I guess!!! (Armchair pondering!)…

What anthropic do you mean? I'm describing properties of models, not people. Physics (probably) doesn't care what you "know". On the guid idea - fundamental particles are indistinguishable from one another in quantum mechanics, so they don't have anything like a guid even in principle. There is no experiment you could perform on an electron to determine whether it had been swapped out for a "different" one, for insta…

Sorry ... I am replying mostly to the dice idea which wasn't you.

Yes correct about the guid idea. My point is the discussion is easier to follow if grounded in reality (as best modelled since that is all we have plus some evidence stored in the same "SSD"!)

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