Quantum Biology: Better Living Through Quantum Mechanics
The quantum properties of photosynthesis…
by Seth Lloyd
So in the spring of 2007 when the New York Times reported that green sulphur-breathing bacteria were performing quantum computations during photosynthesis, my colleagues and I laughed. We thought it was the most crackpot idea we had heard in a long time. Closer examination of the paper, published in Nature, however, showed that something decidedly non-crackpot was going on.
Photosynthesis converts light from the Sun into chemically useful energy inside cells. In photosynthesis, particles of light called photons are absorbed by light-sensitive molecules called chromophores (“light carriers” in ancient Greek), which are arranged in a tightly bound structure called an antenna photocomplex. When a photon is absorbed, a quantum particle of energy called an exciton is generated. (An exciton isn’t a particle in the traditional sense, but it acts enough like a particle that physicists find it useful to treat it as one.
Such mathematical likenesses are called “quasi-particles.”) The exciton hops from chromophore to chromophore inside the photocomplex until it arrives at the reaction center, an agglomeration of molecules that take in the exciton and transform its energy into a form that the living system can put to use to perform cellular metabolism, grow, and reproduce.
The great majority of the energy used by living systems once came from photosynthesis: Every calorie that you consume came originally from excitons that hopped through the antenna photocomplex of a photosynthetic organism…
(read more: PBS Nova - The Nature of Reality)
Details from An Aciente Mappe of Fairyland by Bernard Sleigh, 1872
(via Big Map Blog)
This geomorphic/geologic map of Venus’ northern hemisphere was made by the USGS in 1989.
North and South
"Happiness, not in another place but in this place… not for another hour, but this hour" - Walt Whitman
young and hopper.