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rodin
2009-Aug-08, 06:17 PM
Similarly, according to the chemist John Avery, from his recent 2003 book Information Theory and Evolution, we find a presentation in which the phenomenon of life, including its origin and evolution, as well as human cultural evolution, has its basis in the background of thermodynamics, statistical mechanics, and information theory. The (apparent) paradox between the second law of thermodynamics and the high degree of order and complexity produced by living systems, according to Avery, has its resolution "in the information content of the Gibbs free energy that enters the biosphere from outside sources."[8] The process of natural selection responsible for such local increase in order may be mathematically derived directly from the expression of the second law equation for connected non-equilibrium open systems [9].

http://en.wikipedia.org/wiki/Entropy_and_life

Yes, all very well, but what about the information stored, not as ordered physical elements and compounds to form say the internet, but the actual dissemination and multiple storage/cloning of pure information?

Say half a million people illegally download a video from a shareware site, that will increase the information in their hard drive. Say 6 million people witness the orbit of an extraterrestrial craft (like a Vogon ship) does that create more information in their minds (though as we know from the story shortly afterwards there will be a massive increase in entropy)

Has this kind of decrease in entropy (information) - learning as opposed to simply ordering - ever been factored in?

rodin
2009-Aug-08, 06:20 PM
Does 'quantitative easing' - money inflation at the stoke of a keyboard - increase or decrease entropy? :)

korjik
2009-Aug-08, 07:21 PM
http://en.wikipedia.org/wiki/Entropy_and_life

Yes, all very well, but what about the information stored, not as ordered physical elements and compounds to form say the internet, but the actual dissemination and multiple storage/cloning of pure information?

Say half a million people illegally download a video from a shareware site, that will increase the information in their hard drive. Say 6 million people witness the orbit of an extraterrestrial craft (like a Vogon ship) does that create more information in their minds (though as we know from the story shortly afterwards there will be a massive increase in entropy)

Has this kind of decrease in entropy (information) - learning as opposed to simply ordering - ever been factored in?

you have to look at the whole system. The order created by life is allowed by the disorder created by the Sun. If the Earth was a truly closed system it would eventually run out of free energy and life would not be sustainable. The Sun acts as a energy input and effective entropy sink for life on Earth

Ronald Brak
2009-Aug-09, 12:09 AM
There are a lot of mythology hobbyists who say strange things about life and entropy. But unlike what some of them say, life increases the amount of entrophy in a system. It is often quite good at it. When a movie is downloaded entropy is increased by burning coal to provide electricity for the task. When a brain creates a memory by organizing molecules in brain cells, entropy is increased amoung other molecules, such as those in a person's lunch. So entropy doesn't technically decrease. It's increasing somewhere, but just where may not be readily apparent.

grant hutchison
2009-Aug-09, 12:56 AM
If we look at Earth from the outside, we see pretty much the same energy coming out as goes in: it's more or less in thermal equilibrium.
But for every photon absorbed by the Earth, twenty lower-energy photons are radiated. The entropy per photon is independent of photon energy, so the Earth is an entropy-increasing engine. Our little local decreases of entropy, here on the surface of the Earth, are achieved on the back of that massive increase in entropy by the whole system.

Grant Hutchison

Ken G
2009-Aug-09, 01:18 AM
All good answers, but I detect in the OP an additional question, which is, does the physical concept of entropy incorporate a higher degree of entropy involved in conscious information? In other words, does the evolution of sentience somehow defeat the second law of thermodynamics? Or put differently, is there a difference between knowing something, and knowing that you know something, and how far does that chain extend? What information is involved there, and can it be included in the second law?

I don't know if that has an answer, because we don't really know what sentience is. I can certainly say that most physicists expect that sentience will not disobey the second law, because they expect that being conscious of a fact must involve more information than simply the fact itself (which I agree it must), then there has to be additional entropy increase somewhere else to make that possible. One fact that supports this view is that a brain burns a lot of calories to get its job done. But until we know just what that "job" really is, and how to characterize the information involved, we really can't say for sure whether it is describable with the normal concepts of entropy and information. This is an interesting question rodin-- you are basically asking, is thought spontaneous in the physics sense of the term?

astromark
2009-Aug-09, 03:28 AM
So that leads us to that question "What is sentience ?" and to be aware that we might be aware, is what is being aware at all... my brain is not burning so many calories these days. Entering a new state of confusion... Sigh...

Ronald Brak
2009-Aug-09, 04:36 AM
Sentience is the ability to state that you are sentient combined with the ability to state that looped tape of the statement, "I am sentient," is not sentient.

astromark
2009-Aug-09, 08:20 AM
No Ronald it is not a looped tape. To be aware that we are aware is in itself the explanation of what a sentient being is... Its not about the words we use. Its about the understanding of it.
As for the OP No. Information does not have mass. no amount of information transferral changes these equations of relativity and entropy.

Ken G
2009-Aug-09, 01:08 PM
Since I don't think we even know if sentience precedes language or language precedes sentience, I'd have to stand on my claim we are not ready to say much about the physics of sentience. You can look at animals that don't use higher forms of language, or very young humans, and note that none of them can conform to Ronald Brak's definition. Shall we say a chimp is not sentient? A baby? We just don't know the good definitions well enough to answer that. The dictionary definition centers on ability to use perceptions, but struggles to say how perceptions need to be used, or what a perception even is, before we can call it sentience. Nevertheless, I think most definitions would probably allow that a pre-language child is sentient, so we cannot use the ability to say "I am sentient" as its definition (notwithstanding the paradox involved).

Ken G
2009-Aug-09, 01:11 PM
Given how badly dictionaries struggle to even define this term, and its absence in physics glossaries, I'd have to stand on my claim we are not ready to say much about the physics of sentience. Nevertheless, there are two severe problems with asserting that the ability to say "I am sentient" should count in its definition:
1)I think most definitions would probably allow that a pre-language child is sentient,
2)it is paradoxical to include the ability to use a word in its definition, for who can use a word until it is defined, so how can it be defined in terms of that use?

rodin
2009-Aug-09, 03:03 PM
you have to look at the whole system. The order created by life is allowed by the disorder created by the Sun. If the Earth was a truly closed system it would eventually run out of free energy and life would not be sustainable. The Sun acts as a energy input and effective entropy sink for life on Earth

It would run out of free energy, but energy would be conserved. The Earth would apparently be in more disordered state. But what if a vast lasting library of knowledge was left behind? How to quantify that 'information' and balance it versus the 'information lost' by disordering?

rodin
2009-Aug-09, 03:10 PM
I see other posts have addressed the issue outlined above (and in OP)

rodin
2009-Aug-10, 11:41 AM
The question of the link between information entropy and thermodynamic entropy is a hotly debated topic. Some authors argue that there is a link between the two,[37][38][39] while others will argue that they have absolutely nothing to do with each other.[40]

http://en.wikipedia.org/wiki/Entropy

My guess is that we are still searching for a missing link between information and matter. For how to account for a complex but comprehensible novelty simulcast across the world to millions? And also are ideas actually information?