Sunday, March 6, 2011

How do Bacteria calculate a rate of return on investment

How do bacteria go about calculating a rate of return on investment?

I think that this is one of the most fundamental questions we can ask about life and how it began. If a bacteria is a structure for increasing the entropy of the universe, then how does this structure figure out the best way of increasing the entropy of the universe? It appears that the best way of increasing the entropy of the universe is to maximize the rate of return on work invested, but this can't be proven.
Do bacteria have any means of calculating the rate of return on investment of a certain action? (such actions include moving, consuming food, and self-replicating.)
How does it decide when to move (i.e. expend work), when to consume food (which also initially consumes work), or when to self-replicate (and again this also consumes work)?
Do bacteria have a set rules for when to move, eat & replicate? And if so, what are those rules?
If there aren't set rules, can a bacteria do calculations of the rate of return on investment of its actions?
Either way, where did the rules come from or where did the ability to calculate rate of returns on investment come from?

As I've been discussing in previous posts (Source of Exergy in Early Universe & Meaning of Life), it is likely (but in no way proven yet) that within the equations of far-from-equilibrium thermodynamics is the capability for structures to self-replicate. Right now, we can predict when structures (like Bernard cells) will form in non-equilibrium processes, but we don't have the ability to predict when self-replicating structures (like bacteria) will form in non-equilibrium processes. I had suggested previously that the capability for structures to self-replicate may be due to or related to the ability of the underlying symmetries of the differential equations to be self-referential.
Either way, there should be way of predicting from a set of differential equations (that describe the motions of the large but finite number of chemical species) the likelihood of forming self-replicating structures (like bacteria.)

So, while it's known that bacteria can reproduce at rates as fast as once every 20 minutes, the question remains: how do bacteria attempt to maximize their rate of return on investment? How does a bacteria decide when to self-replicate? And most importantly, how can the self-replication of structures (bacteria) be described using the law of non-equilibrium thermodynamics? (i.e. without adding any non-physical equations)

We need to understand how the simplest bacteria self-replicate. We need to calculate the rate of return on work invested for a bacterial colony. We need to be able to understand whether maximizing the rate of return on work invested is 'programmed' into the DNA-protein synthesis. Do bacteria have the software in their DNA for calculating the return on investment of an action? Do more advanced species have better calculators? If bacteria can multiple so quickly, why aren't they covering every square inch of the planet? Do humans have a better calculator for determining the rate of return on investment than bacteria?

So, let's get back to why I'm ultimately interested in how bacteria operate.  As I've mentioned previously, I want to go back to the basics. I want to get back to basics because many of us in our society are so far removed from the underlying driving force of life that we don't know how the world works. Some of us live in a world of such abundance that we don't know the underlying cause of the abundance...and some of us are so far removed from the source of the abundance that we mistakenly advocate for policies that will ultimately destroy the abundance. In particular, I'm thinking about people who advocate for building electricity generation technologies that have negative rates of return on investment (such as solar PV today.) And I'm not talking about advocating for R&D for these technologies, I'm talking about advocating for the building of commercial scale plants that end up consuming more work (such as electricity) than they generate over the lifetime of the power plant (such as solar PV today.)

The other reason that I'm trying to get back to basics is that I'm getting really tired of hearing the same old arguments from economic classicists (mostly Republicans) and economic Keynesians (mostly Democrats). I think that both classicists and Keynesians have gotten so far removed from the underlying driving force of an economy that they end up talking right past each other. Most undergrad economic textbooks fail to even discuss the economics of electricity generation and vehicle transportation. Both groups of economists also seem to hide the self-referential nature of an economy, and the fact that economies (like the weather) are impossible to predict. When Ben Bernanke tells you that he is 100% confident that his policies will work, don't believe him!  There's no way to be 100% confident in which way the economy will go. A bacteria might be able to calculate an average rate of return on investment by spending work to move to a new location (which might have more food), but there's no way to be 100% sure. The equations of far-from-equilibrium thermodynamics can not be solved deterministically. And the calculation of the average rate of return on investment is approximate because it's self-referential. You have to truncate the calculation and make approximations because the value of the rate of return depends on the amount of work consumed in calculating the rate of return. This vicious cycle can not be re-normalized. There is no way to avoid uncertainty in estimates of future rate of returns on investment.

But with that having been said, I believe that there is no better way to increase the entropy production rate of the universe other than choosing those actions which have a sufficient large value of the average rate of return on investment. In power plant design, I think that this value has to be greater than 5% per year to sustain our current way of life. Many technologies out there (such as solar PV) can not currently achieve an unsubsidized annual rate of return on investment of at least 5%. A value of 7% to 10% is more realistic of what we need to grow our society.

While bacteria can individually reproduce at rates much faster than 5% per year (more like doubly rate on the order of hours), the overall rate of return from bacteria appears to have maxed out millions of years ago. Bacteria do not appear capable of capturing more sunlight and converting it into higher entropy infrared radiation, and they certainly are not launching themselves into outer space in order to colonize other planets (without our assistance.)

So, why I'm personally interested in understanding how far-from-equilibrium thermodynamics can describe the actions of bacteria, I'm mostly interested in learning from the bacteria in how to design self-replicating solar robots that we could use to generate electricity and populate other planets. We have to learn from how bacteria operate in order to create the self-replicating solar robots of the future.

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