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rndphs | 3 years ago

But the movement of ions in solution is almost completely dominated by thermal motion. Your signal doesn't matter if the signal to noise ratio is essentially zero.

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ncmncm|3 years ago

In other words, life is impossible?

That will be surprising to those of us who, you know, exist.

rndphs|3 years ago

No, the molecular machinery of cells uses energy level differences that are far above the thermal energy level at body temperature, which allows them to actually make changes to things irreversibly. Enzymes are a great example of this.

Try to use microwaves to move ions from one side of a container of salt solution to the other and then get back to me on the ability of microwaves to control ion movement. Hint: you basically can't without obscene levels of radiation. The thermal "pressure" due to the diffusion of ions is enormous.

For a sense of scale, the thermal velocity of water molecules at room temperature is about 500m/s. The drift velocity(average movement of charge carriers, i.e. coherent current) of typical electric currents is on the order of 1mm/s.