Quantum Biology

It has previously been thought that the Quantum phenomenon has no business when talking about living systems.

The world of organisms is warm, damp and noisy, while Quantum effects require sterile and cold environments in order to exist. Recent studies show that Quantum “trickery” may occur in living creatures in spite of this contradiction.

The main phenomenon normally not possible in the lack of a proper “air tight” environment is named “Quantum Coherence” - the phenomenon which allows for quantum multiple states (or super position of the Schrodinger wave function).Quantum de-coherence happens as a result of noise(e.g photon and particles) interacting with the Quantum system at hand, essentially nullifying the multiplicity of states.

It has recently been discovered that quantum effects are quite possibly in action even in the tumultuous realm of the living cell.

Photosynthesis, the process in which plants as well as certain bacteria extract energy from the sun in order to generate nutrients, may very well involve quantum mechanics in its working. The random energy from the sun after hitting the chloroplast cells (which are embedded in every leaf), somehow gets transmitted forward in a non random fashion through the photosynthetic process to be utilized at its full potential for the conversion of CO2 to sugar.

This non-random fashion in which the photons excite electrons from molecules into an energetic stream, may very well be coherent, allowing for these electrons to explore several paths simultaneously(!). The questions remains how does this happen amidst the cellular noise?

well, as one MIT Physics Professor suggests (after preforming a relevant computer simulation) - it seems that the noisy environment actually assists the electrons in moving more fluently, and avoiding mechanical obstacles naturally occurring in the cellular space. Gently “shakes” it into position if you will.

Navigation capability of birds (otherwise known as the avian magnetic sensor) is another process mentioned as seemingly quantum mechanical.

When a bird is in flight, a stream of photons interacts with its retinal photo-receptors, resulting in the release of radical molecules (i.e missing valence electrons). These molecules have a semi unpopulated energy level resulting in a magnetic spin quality. The spin of one molecule is magnetically influenced differently than the other, thus shifting the molecules between different quantum states , each of them resulting in different chemical properties. Each quantum state leads to the creation of a certain chemical, and it is believed that the magnetic orientation is somehow a function of the concentration difference between the two.

Further study of the Quantum phenomenon in biological systems may lead to more progressive light harvesting systems, as well as the better understanding of how to enable quantum effects in sterile environments, which would be highly applicable for quantum computation. In Quantum computation, Quantum bits can exist in both states at once, thus permitting the simultaneous exploration of all possible answers to the computation that they encode. Learning how to eliminate decohernce may be an important step forward in the evolution of the field.

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