perhaps what I should be asking is "what is living matter better at than dead matter, on a purely physical level". I'd say that spontaneously generating heat is one thing that it's better at.
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It's not spontaneous, it's just leftover waste heat from a machine. That energy originated from the sun, found its way into plants, then eaten by a cow, and then by me (via a juicy cheeseburger). Since no machine is 100% efficient, at each point during this process some is coverted to entropy (low level heat). Just like a car engine, a refridgerator, or a computer.

So really you should be asking what life and refridgerators and car engines have in common, since they are all good at converting "useful" energy into entropy.

Also, if there was no life, the universe would march on towards heat-death just fine without us, I think.

perhaps what I should be asking is "what is living matter better at than dead matter, on a purely physical level". I'd say that spontaneously generating heat is one thing that it's better at.

It's not spontaneous, it's just leftover waste heat from a machine. That energy originated from the sun, found its way into plants, then eaten by a cow, and then by me (via a juicy cheeseburger). Since no machine is 100% efficient, at each point during this process some is coverted to entropy (low level heat). Just like a car engine, a refridgerator, or a computer.

So really you should be asking what life and refridgerators and car engines have in common, since they are all good at converting "useful" energy into entropy.

Also, if there was no life, the universe would march on towards heat-death just fine without us, I think.
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Surely living things act spontaneously. When you reached for that giant cheeseburger, it was due to an internal stimulus. A rock doesn't do that.

I don't think that the universe would march on toward heat death just fine without life. I know it would. ;) That wasn't my question. My question was whether or not it marches faster with life. What I guess I am asking (myself, others) is if all matter on Earth died, would overall heat transfer reduce. Is a pound of lobster better at converting useful energy into useless energy than a pound of rock? I would think so, given that a rock -- or a dead lobster for that matter -- doesn't spontaneously go about the business of ripping apart the environment.

[quote name='laztrezort' timestamp='1341870937' post='4957429']
Also, "life" is a somewhat vague term. Is a virus alive? Is a prion alive? What about Avida, or Terraria, or the many other artificial life simulations? Many would probably say no to the latter, although they exhibit many (most? all?) of the characteristics that a biologist would define as "living".

A virus is not considered a living thing, a bacteria is
[/quote]

I'm on the fence on that one, with a lot of other people, I'd presume.

Nope, there is none - we are just chemical processes.... once you realise this life gets much simpler

Well, I'll give you credit for going one level deeper than biology. I'm more talking about the physics though. I'm not talking about an existential credo that would make the philosophers proud, or any kind of reason for why life was created. That's why I'm hesistant to agree that anyone claiming that the purpose of life is to fulfill the second law of thermodynamics is arrogant. That's gotta be the most mundane, boring, unimportant, anti-climactic purpose that I could possibly think of. It's practically not a purpose at all; it's almost anti-religious.

Seems to me kinda like asking "What's the purpose of gravity?" We can say what it does, how it affects other things in the universe, and what has come to be as a result of the properties of gravity. But it doesn't have a purpose. It just is.

Life is life. It is what it is and does what it does. Why would it need a purpose?

That's a really good point. I'm going to have to think about that some. I don't know if it's the same kind of question right now. I know "why" the second law of thermodynamics is the way that it is, and if gravity is ultimately about thermodynamics (no concensus on that yet), then we know "why" gravity exists as well. The main difference is that there's only one second law, and one gravity (in the rawest sense, there is only one type of interaction, but symmetries are broken at the lower temperatures, forming multiple facets of that one interaction), and yet there are two forms of matter (living and dead).

I was thinking that living things by their complexity seemingly defy some laws of nature (okay, I haven't thought of the definition "seemingly" and and "defy"). For example a much-heavier-than-air object sometimes goes up a slope or can simply fly. But that definition would fit to machines as well.
I guess "'spontaneously generating heat" is like this. But this means radioactive matter is living?

Some computer games looks like they have their own universe. Some of them has "AI". Yet, we all know that they are really a wast system of some basic switches switching around.

A system can never perfectly simulate itself, maybe that's the reason we find ourselves so unpredictable, and "alive".


A more interesting question to me, that where is the guy sitting at the monitor (my soul ""sensing"" what's going on in my brain) coming from, or does he have any influence on my brain's matter?

I asked myself the other day what the purpose of life is, and what the purpose of the life drive and death drive are.

This question doesn't make any sense and can't possibly be answered in a meaningful way. You've got to unask the question if you want an answer.
Our atoms were forged in the furnace of a sun, exploded into space, clumped into a planet, were spontaneously arranged into the basis of life, evolved for a billion years, and then were arranged to form the neurons in your brain that represent the concept of "purpose" in your own psyche. This is a human concept, which doesn't exist outside of our minds.

How could all the magic that came before the evolution of man be somehow driven by a concept yet to be invented by man? The only way this makes sense is if you create God in your own image, project your personal concepts onto God, and then place Him back in time to guide physics within the framework of your own emotions this time... AKA, religion and superstition, not philosophy and science.

... really love that concept of entropy, and from what I can tell, they all seem to feel that the purpose of life is to create information, or create states that would not normally occur in inanimate matter. This seems like a natural extension of the physics of all matter, where the second law of thermodynamics essentially says that the entropy (average information content per physical state) of the universe is ever increasing.[/quote]Entropy will increase to it's limit with or without life being present in the universe -- this is just the great cooling down of the universe, and we are a part of that cooling down. In the process of all the suns burning up, the generation of intelligent life is a mere footnote, almost invisible compared to the other entropic forces at play.

But there is a small part left out of this extension, which is that entropy production is proportional to heat transfer, and all life forms do seem to give off heat (even a snake will freeze solid in -40 temperature, and a snake eats, whereas a rock does not).[/quote]The heat-transfer definition turns out to only be an approximation of modern entropy. It's also possible for life to decrease entropy in our local region -- in fact, that's what most of our lives is spent doing -- forcing things into a specific arrangement (like a work of art) is a decrease in entropy, not an increase. Entropy is disorder, or the amount of possible ways something could be arranged in -- a work of art is a very ordered and specific arrangement of matter, the opposite. This doesn't violate the 2nd law, because that local decrease is offset by a much larger global increase (such as the burning of the sun's fuel that keeps you alive to perform your transient art).

This turns your idea on it's head, as it seems that the main activity of life is actually to attempt to decrease local entropy by building more and more specific structures.

Of course, life forms require energy input in order to generate entropy (the entire process takes "useful" energy as input and converts it to "useless" energy as output), and so the entire process of entropy generation is not "free", and there are optimizations to be considered (which I suppose is why evolution occurs).[/quote]What force would possibly guide evolution to select based on entropy-generation? It's common knowledge that Darwin's only guiding force was whether an organism lived and reproduced or died. Anything beyond that is "intelligent design" superstition.

When you analyze the interaction between humans or animals or plants or bacteria or whatever, is it all just a giant game of "let's see who can generate the most entropy given a unit of input energy"? Is this why we idolize creative people, like Picasso?[/quote]As above, a Picasso paining is in a much lower state of entropy than a blank canvas and tins of paint, so no, you've got this backwards.

There are clearly differences between living and dead matter, and perhaps what I should be asking is "what is living matter better at than dead matter, on a purely physical level". I'd say that spontaneously generating heat is one thing that it's better at.

"Better" implies selection -- natural selection occurs in organisms as some are killed by the environment -- are you suggesting that the universe itself has a hidden force that somehow select organic arrangements of molecules and promotes them, in order to optimise for entropy?
This is an unnecessary addition to any theory -- we can explain the existence of organic compounds without invoking magic and superstition.

As for the differences between living and dead -- this again is a human concept... If you look at them on another scale, they look the same. At the cosmic scale, they're both just dust on a pale blue dot. At the atomic scale, they can both be made up of the same elements, and at the quantum scale, everything starts to look pretty much the same.
In fact, the very concept of saying "this is one object, this is a separate object" is again a human invention. If some form of M-theory is right, then the entire universe may be able to be described with a single geometrical description, without boundaries between different "objects" that even allow for the concept of "separation".

It occurred to me that if the purpose of life is to increase the entropy of the universe in an optimal way, by increasing the occurrence of heat transfer, and that life will be impossible in the far future because the universe will be in thermal equilibrium at maximum entropy[/quote]Yes, live will be impossible in the far future, but that's going to happen regardless of whether it gets there in the most optimal way or not.
If the universe wanted to optimise for heat transfer, why doesn't it generate more efficient-burning stars, instead of tiny, tiny, tiny, tiny little ants on a tiny, tiny, tiny, little blue rock? Humans seem incredibly inefficient at a cosmological scale. In fact, if the parameters of the universe (i.e. the curvature of the other 7 spatial dimensions) were tuned optimally for this, then the element of carbon would've been impossible to form, and the stars would've all burnt up before even making a single planet. We know this isn't the case though.

Surely living things act spontaneously. When you reached for that giant cheeseburger, it was due to an internal stimulus. A rock doesn't do that.

That's debatable. It's a common view that humans, and all life, are still just deterministic machines. Indeed if you study biology, it's hard not to see the different components of cells as microscopic robots.
If there's no magic soul duality going on, then indeed, we're just the same deterministic stuff as the stars -- and our behaviours are indeed just as predictable as the falling of a rock, just with an order of magnitude more variables involved (meaning WE will likely never be able to make those predictions).
In fact, if human actions were truly spontaneous and inexplicable by physics, then we would have proof of God meddling with the affairs of the universe... unfortunately, physics can explain our actions without invoking God.


Let's imagine the universe as a perfect circle, with circular particles inside it. It started out in a big bang as a dot, and grew over time into a big circle.
If we stack all the future states on top of each other, we've now got a 3D cone that represents both space and time (i.e. space-time). Looking at this new geometry where time is just another axis, or location in a coordinate-type, is much more beneficial than the illusion that you perceive of a slice though that axis.


You're currently exist at a particular point in the cone, and your life is a series of these points, forming a line. That's your world-line, and it already exists.

Time is another human concept, and is just an illusion. What you're experiencing as the past is your memories, created in a process that follows the arrow of entropy (not the arrow of time). The laws of physics work just as well backwards as they do forwards in any axis, including the time axis. The point at the start and end of that line are just as "objectively real" as the point you find yourself at right now; this is a fact of physics, and is why many physicists shy away from supporting the idea of an "objective reality" at all, preferring only the realities defined by their models...
However, this doesn't mean that your "fate" is fixed and there's no "free will" -- when looking at a particular point on a world-line, to explain that point's past, you've got to examine every world-line that could have possibly led up to that point, calculate their quantum probabilities, and sum all infinity of the terms to take interference into account. This means you don't just have one past, but every past that could have produced this moment is equally real. It's only during the quantum decoherance in that pile of qubits in your head that you end up with the illusion of a single reality, instead of the truth of a superposition of realities. All that's imagined and all conceivable, does actually exist somewhere in this superposition of the universe.
Same goes for your future, where at every point/event on that line, an infinite number of future lines branch out and are equally "real".

The illusion of there being a lot less degrees of freedom than there actually are is just a predictable by-product of the design of your machinery.

I asked myself the other day what the purpose of life is, and what the purpose of the life drive and death drive are.

Has anyone here read much of anything in terms of evolutionary psychology, evolutionary biology, Dawkins, Zizek, Lacan, Jung, Freud? The psychologists/psychoanalysts/biologists really love that concept of entropy, and from what I can tell, they all seem to feel that the purpose of life is to create information, or create states that would not normally occur in inanimate matter.

Why do you think there needs to be a 'purpose' of life? Even the wording 'purpose' almost implies a creator, which makes me tend to think you have been strongly influenced / have a religious / magical view of the world.

I've read quite a bit of dawkins, and used to work in the academic biological world, and I can tell you that entropy doesn't get mentioned much, and to say that 'all feel the purpose of life is to create information, or create states that would not normally occur in inanimate matter' is completely untrue. If anything, most scientists would take an opposing view to this.

To most scientists, life is just a property that tends to arise as a result of the matter that's floating around, and the laws of physics. Atoms / molecules often have a tendency to react with each other, as a consequence of the laws of physics. This is called chemistry.

Some particular groups of atoms / molecules have a particular property that they are able to replicate themselves. You can think of this as analogous to the situation of crystallization, where a 'seed' crystal can form the environment into the same shape and replicate the structure to form a bigger crystal.

The formation of these 'seed' replicators may be quite unlikely by chance. But if you have a vast 'pre-biotic soup' of chemicals on the surface / within planets (probably) then by virtue of the sheer number of molecules forming (zillions) and time, you have a recipe that just some of them may form into 'self replicating' forms.

To reach self-replicating forms may require specific combinations of elements present, or certain combinations of temperature, pressure etc. We don't really know. All we know is it may have happened on earth (but not necessarily, the self replicating forms may have drifted in from space, for example, I'm a fan of this theory).

Once you have self-replication going on in favourable conditions, the rest is almost bound to happen.

The basic ingredients for evolution are:

1) Replication (or reproduction)
2) Imperfect replication, some variation
3) Inheritance of this variation

If you have basic replicating molecules replicating in some prebiotic soup, all kinds of fun stuff can happen. They can start using up the resources (atoms and molecule building blocks) so they may start to compete for the resources. There is evolutionary pressure towards structures that are good at replication, and that are able to outcompete their neighbours, perhaps by 'eating' their neighbours, and using their resources to reproduce.

At some point you get the formation of reliable stores of the 'building instructions' for a replicant. At some point you get RNA and DNA, but before that there were very probably precursor ways of storing building instructions (genetic code) that became more and more resistant to damage by the environment, thus making the replication more and more efficient.

The rest as they say is history, I could go on, but there are plenty of books / articles that explain this better and in more detail.. the 'leaps' in evolution, formation of RNA, DNA, cells, single cells, colonies, multi-cellular organisms, differentiation of tissues etc etc.

So anyway, to ask what the 'purpose' of life is, is pretty much like asking 'what is the purpose of the physical laws', or 'what is the purpose of matter'. Rather than using the word purpose, and just asking 'why do they exist', is a question that affects everyone, whether their views are religious or not. I think there's a lot of work going on in this, this is the kind of questions the particle physicists are asking looking at things like the higgs boson. It may be that the physical laws are a consequence of maths, there are all kinds of theories, string theory, resonant frequencies etc, I don't know that much about it.

Why is there anything at all? Why is there matter and not 'nothing' .. I don't think anyone knows yet, but I'm sure the answers will be interesting.

I think the entropy idea is barking up the wrong tree. It's a nice overall rule that works well for simple processes in chemistry, and 'buckets' of larger amounts of matter, but life is not a simple process. You can say, overall that there might be an increase in entropy or whatever, but it's not really a useful measure when working on the scale of organisms.

Why is there anything at all? Why is there matter and not 'nothing' .. I don't think anyone knows yet, but I'm sure the answers will be interesting.

I'm not trained in QFTs, but according to Hawking, if you construct a perfectly "empty" QF with zero energy, then the equations show that quantum fluctuations will spontaneously cause it to un-balance into areas of both positive and negative energy (still summing to a total of zero). His explanation of why this is true went over my head, but he then treats the question of "why something rather than nothing" as another nonsense question, such as "what happened before the beginning of time", which doesn't need an answer once you start thinking about the question correctly (in 4D spacetime, the beginning of time is equivalent to the south-pole of a 3D sphere -- asking what's more south than the south pole is obviously nonsense, as it's not actually a boundary but a smooth geometry without end).
Also, apparently if you sum up all the various stuff in our universe, the sum total will be zero energy...

I'm not trained in QFTs, but according to Hawking, if you construct a perfectly "empty" QF with zero energy, then the equations show that quantum fluctuations will spontaneously cause it to un-balance into areas of both positive and negative energy (still summing to a total of zero). His explanation of why this is true went over my head, but he then treats the question of "why something rather than nothing" as another nonsense question, such as "what happened before the beginning of time", which doesn't need an answer once you start thinking about the question correctly (in 4D spacetime, the beginning of time is equivalent to the south-pole of a 3D sphere -- asking what's more south than the south pole is obviously nonsense, as it's not actually a boundary but a smooth geometry without end).
Also, apparently if you sum up all the various stuff in our universe, the sum total will be zero energy...

Actually yes that kind of makes sense, I must read Hawking's book. I have to admit while I have quite reasonable understanding of evolution and life, most of these new physics ideas totally boggle my mind. It may be that part of the reason we (us non-physicists) find it hard to understand is that we have evolved for dealing with concepts in our 3d world (with time going forwards), and once you start challenging those assumptions, by adding extra dimensions, bending spacetime etc, we are not very well equipped for visualizing it, except maybe in mathematical terms.

On the other hand maybe it's hard to understand simply because we don't have all the answers yet. Maybe once they figure out the grand unifying theory it will be taught in secondary schools, and it won't be so difficult. Perhaps there's just a few pieces of the jigsaw missing, and once they are there, it will suddenly 'all make sense'.