4.25.2007

in which i digress from my own knowledge

... and speculate on fields in which i am no expert, nor a student, but merely an outside observer.

for some reason, it's not particularly common among scientists to believe in astrology, or to check one's horoscope each morning before leaving the house. but while it's doubtful that "personalized" daily predictions could ever be accurate - beyond what happens by coincidence and vague wording - there's one gaping hole in our understanding of the fundamentals of physics, and it might have something to do with astrology.

(caveat: speculative, moderately crazy-talk thinking follows.)

ok, i'm no physicist, but i do have a pretty good working understanding of mechanics and electromagnetism. i'm a bit shakier on the whole quantum thing, but i at least have a decent grasp on the basics, and can accept the fact that fundamentally, everything is stochastic and based entirely upon chance. (which is not to say that it is random.)

what's missing from our Theory of Everything is how gravity comes into play with the whole quantum theory thing... how it interacts with atoms and molecules, what forces gravity might exert on a chemical reaction. there have been numerous (purely theoretical) attempts to explain gravity's place in quantum theory: string theory and loop quantum gravity come to mind. frankly, i don't understand either one nearly enough to explain it. but it is true that gravity must *somehow* act at the molecular level, or else we wouldn't all be here. and there are other things at the large molecular level (protein folding is a big one) that have yet to be explained by anything but the most complex of computations (for the simplest proteins). and it's not just that. how does a protein find its binding partner, when the concentration of the ligand is infinitessimally small (in the case of biotin and streptavidin, the most extreme example, on the order of 10^-15 mols/liter, or the femtomolar scale*)? what determines whether one single (but critical) sodium channel opens or stays shut, triggering or preventing an action potential that could lead to many downstream consequences?

could gravity somehow be the answer? could the mass of the earth exert an influence on chemical interactions within cells? could the moon? the sun?

how the hell would you go about testing something like that?

* digression: i'm not sure you really get how tiny femtomolar concentrations are. Avogadro's number is 6.02x10^23... i'm going to round and call it 10^24. So there are 10^24 molecules in a mole, or 10^24 molecules per liter of solution at 1 molar (M). If the concentration is 10^-15 M, then that means there are 10^9 molecules, or about 10 billion, in a liter of solution. Now consider the fact that the volume of an average cell is around ***quick calculation*** 1.25x10^-16 (mm^3). a cubic millimiter is the same as a microliter of water - 10^-6 liters. so that makes our cell volume 1.25x10^-10 liters. 10^9 molecules per liter times 1.25x10^-10 liters = .125 molecules per cell volume. and yet this is how low the concentration of streptavidin must be before half of the bound biotin releases its SA! tell me there isn't something freaky going on there.

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