All persistent dynamic structures are fundamentally circular motion. And there has to be an energy gradient to drive the motion against the resistence that is required to reproduce.
So, imagine a torus in a bath of molecules such that the torus rotates in proportion to the flux of light through it's hole. The torus rotates not like a steering wheel, but around itself (called poloidal rotation), such that the inside squeezes together and the outside expands. This might catch molecules from the surrounding bath, expanding the torus, changing it's shape. It would also tend to change it's relationship to incident light.
At some point, the torus could "shed" a second torus, roughly equal to it's original, smaller shape, which would participate with the environment in the same way, aggregating energy and matter to reproduce itself, until either all light is consumed, all free matter is consumed, or both.
Anyway, I'm not sure if this is all that realistic - but I think it captures the important quality of "life" when it comes to physics, mainly that life is circular motion that has the general character of memory and reproduction.
>life is circular motion that has the general character of memory and reproduction.
This is totally random but that bit reminded me of a quote from Black Elk Speaks:
>Everything the Power of the World does is done in a circle. The sky is round, and I have heard that the earth is round like a ball, and so are all the stars. The wind, in its greatest power whirls. Birds make their nest in circles, for theirs is the same religion as ours. The sun comes forth and goes down again in a circle. The moon does the same and both are round. Even the seasons form a great circle in their changing, and always come back again to where they were. The life of a man is a circle from childhood to childhood, and so it is in everything where power moves. Our tepees were round like the nests of birds, and these were always set in a circle, the nation's hoop.
That's lovely, but my meaning is a little more specific and technical, and comes from the singular observation that Life cannot be constructed from unbounded linear motion. The sun shines on the planet, making things move, but gravity pulls it all down again. It's only "circular" in the same sense that a human can be approximated by a sphere of water.
So, imagine a torus in a bath of molecules such that the torus rotates in proportion to the flux of light through it's hole. The torus rotates not like a steering wheel, but around itself (called poloidal rotation), such that the inside squeezes together and the outside expands. This might catch molecules from the surrounding bath, expanding the torus, changing it's shape. It would also tend to change it's relationship to incident light.
At some point, the torus could "shed" a second torus, roughly equal to it's original, smaller shape, which would participate with the environment in the same way, aggregating energy and matter to reproduce itself, until either all light is consumed, all free matter is consumed, or both.
Anyway, I'm not sure if this is all that realistic - but I think it captures the important quality of "life" when it comes to physics, mainly that life is circular motion that has the general character of memory and reproduction.