Science is pretty much in agreement that all life on earth evolved over billions of years from much simpler single celled organisms. What is less obvious is where this first single cell came from. No theory is of yet completely satisfactory.
Some people insist that this single cell was placed on earth by God, in the knowledge that it would evolve into all of the plants and animals that we see today. This however is obviously not a very satisfactory solution.
Other people claim that the single celled organism arouse by chance, from random chemical mixing from the primordial soup. The chances of this happening are admitedly astronomically tiny. Even given the immense vastness of the universe, it is still highly unlikely. Some make the point of the possibility of a multiverse, so that even though the possibility of life arrising in a single universe is incredibly unlikely, given a near infinitude of universes, it becomes plausable. the fact that we are hear to ponder this question is proof that we inhabit the incredibly "lucky" universe. Again this is not really a very satisfactory answer.
Another theory is that life evolved from unliving material. Material with the power to grow and to replicate its own structure is a possible ancesstor to this cell. I won't go into the details too much here, but this is actually a more reasonable argument than it may sound. The example of crystalline structures is a good one, which can take in the required elements from its environment (feed) and use these to replicate its own structure. The probelm with this theory is that there is very little evidence for it. Most notably, where are the border line lving/dead structures today?
The list of theories of the origin of the "proto-cell" go on and on. However, one very interesting theory is the idea of Quantum Evolution. I seems quite plausible. The following extract requires a basic grasp of the concepts behind quantum mechanics, most notably the inverse-quantum-zeno effect (it is however expalined briefly).
Quote:
Think about the multidimensional walk that led to the self-replicator. It should be familiar in that it strongly resembles the way the inverse quantum Zeno effect can direct a quantum system along a particular path. The inverse quantum Zeno effect represents one of the peculiarities of quantum measurement, whereby a dense series of measurements along a particular path can draw that system along that path. Insertion of extra polaroid lenses, between vertically and horizontally polarized lenses (a perpendicular or orthogonal pair) rotates the angle of polarization of light. Without the extra lenses, the distance between the two states (vertical and horizontally polarized light) is too great. No light gets through. But the insertion of the extra lenses - each performing a quantum measurement - lays down a series of stepping stones which rotates the light from one state (vertically polarized) to another (horizontally polarized) in a series of short hops. A sufficiently dense series of measurements will lay down a path that will allow the photons to evolve smoothly from one state into another. Similarly, a dense series of quantum measurements of a particle along a positional path can move the particle along that path. The path may be only one out of a trillion equally probable, but quantum measurement can force the system to evolve in that measured direction.
But isn't this more or less what we want to do when we evolve the single amino acid arginine (R), along a single path through peptide multi-dimensional space to synthesize the self-replicator, RMKQLEEKVYELLSKVACLEYEVARLKKLVGE? In classical terms, the probability of the peptide taking the right route is close to zero (in fact 1/10^32). But if quantum measurements were performed along the route, then the inverse quantum Zeno effect could make that path much more likely. Can the inverse quantum Zeno effect make the reaction more probable? To see how, recall how the inverse quantum Zeno effect actually works. It depends on the ability of oblique quantum measurements to decompose a quantum state into sets of orthogonal (perpendicular) states. Measurement then forces one of those states to become real, and a dense series of measurement forces the system along the measured path. The polarization state of photons can be rotated by the inverse Zeno effect, as can the position of particles. If positional measurements can be performed to move electrons around in empty space, they can equally be performed to move electrons (or protons) around in the space of atoms and molecules.
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Coninued on next post. Damn 5000 characters post limit!
