what is more realistic?

Let's talk about this actually.

OK let us suppose that cosmologists (astronomers and astrophysicists) are still dead wrong in their conception of the universe; Not an unreasonable assumption considering that almost every claim they've ever made has turned out to be false in the history of the world.

Let us suppose then that the universe is much older, and is not exploding or contracting, but just chugging along doing its thing that it does; namely, holding together by invisible threads and operating like clockwork, following the laws of physics, and doing so just because it is and does so.


Here comes the subject of life. "Life is amazing, life is incredible", people claim. But is it?

Is it any more amazing than say, this:



Or this:



That is: Is the fact that life exists anymore amazing than the fact that anything exists, at all? These planets and their peculiar make-ups have been hurtling through space doing this dance for who knows how long. Given the number of craters on many of the moons in the solar system, it could be much much longer than current estimates.

So, returning to our original point: Things continue to exist because they exist now. And life continues to exist because it exists now. The core drive of life ... what defines life ... is the strategy it imposes on surrounding matter to continue and promote its own (or own class of) existence. The cell membrane itself is almost completely all of what life is; It protects its own constitution through defenses, and launches an attack on molecules it wants to capture to further its existence.

Given this brief ontological analysis, we might look further to see how one could come about through the other. That is: how the fact of existence and being might, by its own terms, lead to the fact of some life, and thereby to the fact of all life.

Let's pretend there exists a cloud or soup of molecules in some part of the universe, at some time, and these molecules are of the nature that they are unable to react, but yet contain reactant energy which might be released if only they were spread less thinly and had requisite other molecules which are also spread too thinly.

So this soupy thing sits there for a few hundred quadrillion years perhaps, not doing much of anything. One day the correct causal chain occurs to produce a molecule somewhere which is almost a type of catalyst. It bonds with one reagent, floats over to the second, has its freshly bonded atom bond instead with that, and absorbs the energy difference, which makes it attractive to a third type of molecule, which it bonds with, and so on.

The exact process by which this occurs is beside the point. The point is that all one needs in this situation is a type of molecule (or set of molecules) with the unintentional character that it operates in a manner that preserves its class of existence; That is: it operates in such a way that it extracts energy from some situation where a chemical reaction would not ordinarily occur, and, in so doing, reproduces new molecules of its own form.

Now remember these molecules are not alive per se, because it is such a simple thing. So perhaps these molecules went through this cloud and consumed all the reagents there and then just sat there for another quadrillion years. This is possible. Then the process repeats, and thus slowly builds longer molecules out of shorter ones.

You might be able to see that after perhaps a few billion iterations, there would exist more than one type of 'life' molecule in this soup, and thus we have the start of a food chain. That is: the earlier revisions of the molecules are still converting at the level which they have always converted at, and the higher level molecules are feeding off those lower level molecules.

Repeat repeat repeat again and again, over a very long period of time. Keeping in mind the universe is a dynamic and radioactive place. The third most abundant substance in the universe, as far as we know, is water. The earth is constantly hit by chunks of space-ice. Eventually these molecules spread around, get caught in ice, the ice sits there for a long time, eventually a solar system passes by, gravity attracts the ice, it lands somewhere, the molecules do their thing wherever it lands, and voila.

All you need is a lot of lot of lot of time, and life becomes a plausible result of basic chemical and physical laws.

Of course this is mostly reasoned speculation. The main place I differ with mainstream abiogenesis on this is the amount of time it took, and that I don't think its particularly likely to have happened on earth. If you consider the history of the evolution of life necessarily sits on an exponential scale starting at the simple atomic level, this thing has been going practically forever.

Edit:
Also let me add as an addendum: the argument that life must have a single origin because DNA is shared, rests on a flawed assumption: that the structure of DNA is essentially arbitrary. It is quite as incorrect as assuming that all solar systems must have a common origin because they contain spherical planets that persist in circular and elliptical orbits. To me, it seems more likely that life shares that with other life, which is simply the logical outcome of the physical laws that must be obeyed for life to exist in the first place.