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(... let alone the "lowest energy resting state", which would correspond to absolute zero.)

You're completely twisting my words and the idea I clearly described.

Remember the example of marbles setting on a flat are of ground, 1 layer thick. When I said lowest energy resting state I put flesh on it by describing it as marbles sitting on a flat surface - not as some absolute zero thing.

A cell exists as a "dissipative structure". That is, the arrangement of its parts is maintained by the flow of energy through its chemical pathways.

Absolutely - and the mechanisms which force the energy to take the "long way around" thereby doing work for the cell - this mechanism is built up of structures of molecules which are not in the formation that they naturally arrange themselves. It is truly a bootstrap process!

Of course, such structures as these offer only an analogy to any proposed model of the emergence of primordial life,

Remember, an analogy does not prove a thing - it is only a learning aid tool, and it is only useful to the degree that it is accurate.

but there is no question of a bunch of molecules lying around in thermal equilibrium and just happening to form into cellular structures.

Are you saying that you believe that if you mix up a bunch of molecules (which are not self-replicating metabolizing) you'll get a self-replicating and metabolizing living cell...?

Show me! I say that takes a lot of faith and didn't happen.

Thanks,

-Jesse

This is exactly the absolute zero thing! Molecules at room temperature are analogous to marbles in a violently vibrating box, and kept in equally violent motion by the vibration.

Are you saying that you believe that if you mix up a bunch of molecules (which are not self-replicating metabolizing) you'll get a self-replicating and metabolizing living cell...?

Paper in white the floor of the room, and rule it off in one-foot squares. Down on one's hands and knees, write in the first square a set of equations conceived as able to govern the physics of the universe. Think more overnight. Next day put a better set of equations into square two. Invite one's most respected colleagues to contribute to other squares. At the end of these labors, one has worked oneself out into the doorway. Stand up, look back on all those equations, some perhaps more hopeful than others, raise one's finger commandingly, and give the order "Fly!" Not one of those equations will put on wings, take off, or fly. Yet the universe "flies". - John A. Wheeler

I don't claim to speak for dr_lew, but you seem interested, inquisitive, and honest enough... so I'll give it a shot.

Are you saying that you believe that if you mix up a bunch of molecules (which are not self-replicating metabolizing) you'll get a self-replicating and metabolizing living cell...? Show me!

There exist a number of models for abiogenesis. Harvard recently launched a new Origin of Life program to continue and promote the field of research. One of the labs which will be leading this initiative is likely the Szostak Lab, which has done lots of very nice research on protocells. They integrate with other labs in a nice public, interactive front-end. Anyway, that's a nice slice of where you can get the current state-of-the-art on origins research. As I said, this research promotes a number of possible models for the origin of life which continue to be tested and refined. I wanted to introduce you to my favorite.

As you mentioned, any theory of the origin of life must include self-replication and metabolism. I think it's a little more subtle than that:

Self-replication: This isn't restricted to centriole-driven cytokinesis as you seem to imply in your later "It's very complicated" Demskiism post. Lots of things self-replicate. It's not very difficult to do. Anything that can grow and spread is effectively self-replicating, though we would not call it alive. Fire and crystals are good examples. Both grow and "reproduce" just like things that are alive, but we still don't call them alive. So, we need more.

Metabolism: This also isn't dependent on a certain form - like one that is dependent on the Kreb cycle, ATP-synthase, or any complex molecule. Any mechanism that is available to do work for the cell is a good candidate for the first "metabolism". The most common, and probably the simplest, driver of work is heat. From the sun, from geothermal vents, etc. Heat creates lots of interesting processes that could drive the first cell - pressure gradients and fluid flows, chemical gradients and osmotic pressures, organic chemicals and alternate chemistries, etc.

A good starting point for almost all theories of the origin of life has been the fatty acid micell or liposome - a self organizing layer of molecules which form a cellwall-like barrier and can capture large molecules inside them (that's how soap works). Fatty acids are produced naturally and can grow, fuse, and divide. Here's a good study which looks at these properties in the context of a protocell model. And here's a page with videos and simple explanations.

But no one would call this life, we still need some sort of self-replicating molecule. There's a number of candidates... many types of nucleotides and this is where most of the current research is. We're looking for the best candidates to self-polymerize or autocatalyze. The best candidate is simple RNA, which can catalyze its own template polymerization. Once polymers are formed on the inside of a micell (either be captured there or formed there) they become trapped, unlike the individual nucleotides. Template based polymerization can copy the strand without the use of proteins. If the "cell" is heat cycled (like in a geothermal vent, ocean current, etc) the polymers can separate and repeat the process. At this point, there's a competition for nucleotide bases. The favored protocells are the ones with polymers that have the right concentrations of nucleotides, replicate the fastest, explore polymer enzymatic activities, etc. We called this the "Bubble Wars" in my graduate classes.

I was delighted when I saw this video made for the YouTube crevo debates which explains mostly the same thing. That user is very well versed and has some very good videos I recommend checking out. There's plenty of others in the related videos section too.

So, we have a model for the first self-replicating protocell built from simple and naturally occurring substances, driven by thermodynamic processes to compete for resources.

Hope that's some food for thought.