I think one shouldn’t think of entropy as fundamentally preferred or fundamentally associated with a particular process. Note that it isn’t even a well-defined parameter unless you posit some macrostate information and define entropy as a property of a system + the information we have about it.
In particular, life can either increase or decrease appropriate local measurements of entropy. We can burn the hydrocarbons or decay the uranium to increase entropy or we can locally decrease entropy by changing reflectivity properties of earth’s atmosphere, etc.
The more fundamental statement, as jessicata explains, is that life uses engines. Engines are trying to locally produce energy that does work rather than just heat, i.e., that has lower entropy compared to what one would expect from a black body. This means that they have to use free energy, which corresponds tapping into aspects of the surrounding environment where entropy has not yet been maximized (i.e., which are fundamentally thermodynamic rather than thermostatic), and they also have to generate work which is not just heat (i.e., they can’t just locally maximize the entropy). Life on earth mostly does this by using the fact that solar radiation is much higher-frequency than black-body radiation associated to temperatures on Earth, thus contains free energy (that can be released by breaking it down).
It’s easy to confuse entropy with free energy. Since energy is conserved, globally the two measure the same thing. But locally, the two decouple, and free energy is the more relevant parameter here. Living processes often need to use extra free energy to prevent the work they are interested in doing from getting converted into heat (e.g. when moving we’re constantly fighting friction); in this way we’re in some sense locally increasing free energy.
I think a reasonable (though imperfect) analogy here is with potential energy. Systems tend to reduce their potential energy, and thus you can make a story that, in order to avoid just melting into a puddle on the ground, life needs to constantly fight the tendency of gravitational potential energy to be converted to kinetic energy (and ultimately heat). And indeed, when we walk upright, fly, build skyscrapers, use hydro power, we’re slowing down or modifying the tendency of potential energy to become kinetic. But this is in no sense the fundamental or defining property of life, whether we’re looking globally at all matter or locally at living beings. We sometimes burrow into the earth, flatten mountains, etc. While life both (a), can use potential energy of other stuff to power its engines and (b), needs to at least somewhat fight the tendency of gravitational kinetic energy to turn it into a puddle of matter without any internal structure, this is just one of many physical stories about life and isn’t “the whole story”.
I think one shouldn’t think of entropy as fundamentally preferred or fundamentally associated with a particular process. Note that it isn’t even a well-defined parameter unless you posit some macrostate information and define entropy as a property of a system + the information we have about it.
In particular, life can either increase or decrease appropriate local measurements of entropy. We can burn the hydrocarbons or decay the uranium to increase entropy or we can locally decrease entropy by changing reflectivity properties of earth’s atmosphere, etc.
The more fundamental statement, as jessicata explains, is that life uses engines. Engines are trying to locally produce energy that does work rather than just heat, i.e., that has lower entropy compared to what one would expect from a black body. This means that they have to use free energy, which corresponds tapping into aspects of the surrounding environment where entropy has not yet been maximized (i.e., which are fundamentally thermodynamic rather than thermostatic), and they also have to generate work which is not just heat (i.e., they can’t just locally maximize the entropy). Life on earth mostly does this by using the fact that solar radiation is much higher-frequency than black-body radiation associated to temperatures on Earth, thus contains free energy (that can be released by breaking it down).
Maybe I’ll add two addenda:
It’s easy to confuse entropy with free energy. Since energy is conserved, globally the two measure the same thing. But locally, the two decouple, and free energy is the more relevant parameter here. Living processes often need to use extra free energy to prevent the work they are interested in doing from getting converted into heat (e.g. when moving we’re constantly fighting friction); in this way we’re in some sense locally increasing free energy.
I think a reasonable (though imperfect) analogy here is with potential energy. Systems tend to reduce their potential energy, and thus you can make a story that, in order to avoid just melting into a puddle on the ground, life needs to constantly fight the tendency of gravitational potential energy to be converted to kinetic energy (and ultimately heat). And indeed, when we walk upright, fly, build skyscrapers, use hydro power, we’re slowing down or modifying the tendency of potential energy to become kinetic. But this is in no sense the fundamental or defining property of life, whether we’re looking globally at all matter or locally at living beings. We sometimes burrow into the earth, flatten mountains, etc. While life both (a), can use potential energy of other stuff to power its engines and (b), needs to at least somewhat fight the tendency of gravitational kinetic energy to turn it into a puddle of matter without any internal structure, this is just one of many physical stories about life and isn’t “the whole story”.