Abiogenesis, Part I
This is more of a brain dump of what I have learned than anything else, so apologies if I ramble a bit.
I do not claim that science has all the answers here (this is an active area of research). But much like the early Church's stance on the Earth being the center of the universe, abiogenesis research has broken claim after claim made by the creationists about how it "must be" and what science has been able to piece together is a compelling series of events. It takes absolutely no faith to see the incredible progress that has been made in this field over the past 55 years (that is, IF the person bothers to actually investigate this field of study).
The original timescale involved was ~0.7B years in a lab the size of the entire Earth (possibly the solar system) so we have a lot of catching up to do in understanding the most likely pathways that the early Earth could have taken in creating the first organic "life" (some chemical structure capable of self-replication, mutation, and natural selection).
If creationists want to prove that abiogenesis is impossible then only need to find some specific STEP that absolutely cannot have happened naturally. Not a fallacious statistical argument saying that it's just too improbable to believe. An actual chemical combination that cannot possibly happen in nature and the specific, scientific reasons why.
So, what evidence do we have in support of a natural abiogenesis?
Here is a good review for starters: How life began on Earth: a status report
Remember that the DNA/RNA genetic system we have today is just what things have evolved into, don't assume they are required to kick start the process. What scientists generally believe happened was that there was a boot strapping process leading up to that first strand of self-replicating material (be it RNA/DNA or something else).
Peptide chains are simply "shorter" chains of amino acids (aka proteins). These naturally formed chains can perform functions, they can "store information", they change over time, and they can reproduce (e.g., see prion research). Those are all the things required for "evolutionary" processes to work over time.
(1) First of all, Jeffrey Bada's experiment showed once again that a wealth of organic chemistry and amino acids are generated naturally in the early Earth environment. There is also the later Miller experiment about organic chemistry in icy conditions (so it could be that an ebbing between warmer and colder conditions are required). The original Miller-Urey experiment was validly criticised for an inaccurate starting mixture, but even later versions of that experiment had corrected those problems.
(2) We are now also aware of a large number of exogenous sources of organic precursors (IDPs, Meteorites, Asteroids, Comets)
Murchison meteorite: 14,000 specific compounds, including 70 amino acids, were identified...tip of the iceberg
(3) This soup can include shorter fatty-acid chains (created in geothermal vents on the clay walls) which under certain Ph conditions naturally form into protective vesicles, these vesicles can also divide under mechanical conditions AND they tend to combine with smaller vesicles into larger ones such that the contents are merged as well -- but tend to only grow so large before undergoing mechanical division.
(4) Unlike modern cell walls, these primitive vesicles are porous which allows building blocks in, which combine with other components and then are too large to escape
(5) Eventually, some of the peptide chains prove beneficial to the fatty-acid vesicle structures.
(6) We know that some peptide chains are self-replicating -- by setting up even a simple peptide chain which can self-replicate we set the stage for evolutionary processes over time to work. And we know that some single RNA strands have been found to be capable of replication as well.
(7) We also know that the Qb virus can reproduce without a cell if the chemical environment is available.
See The Fifth Miracle by Paul Davies (excerpt)
(8) Finally, we're just now at the stage where we can start building complex life from scratch directly in the lab:
See Chemical Synthesis of Poliovirus cDNA: Generation of Infectious Virus in the Absence of Natural Template
There are, of course, many open questions, nobody is denying that -- but they are just questions and there is absolutely no indication that any of these problems are intractable (including ribose and chirality). Try Google Scholar: abiogenesis ribose
There are 100's of more research papers on the subject, this is just barely scratching the surface.
One of the big problems with religious belief structures which claim revelatory knowledge from God is that it blocks people from even attempting to understand what is true. Where in the bible does it explain the mechanism that God supposedly used to create the universe and to create life? If it doesn't speak to the how, then how do you claim to know that organic life could not have happened as part of the natural course of the universal laws which ultimately drive everything?
You should investigate further: Dr M Reza Ghadiri and Dr Jack Szostak
How do you get to RNA without the mechanisms in place today to create it?
That is now at least a half-solved problem, See Dr. Sutherland's research:
the chemicals naturally formed a compound that is half-sugar and half-base. When another half-sugar and half-base are added, the RNA nucleotide called ribocytidine phosphate emerges. A second nucleotide is created if ultraviolet light is shined on the mixture. Dr. Sutherland said he had not yet found natural ways to generate the other two types of nucleotides found in RNA molecules, but synthesis of the first two was thought to be harder to achieve. If all four nucleotides formed naturally, they would zip together easily to form an RNA molecule with a backbone of alternating sugar and phosphate groups.
And even that may have come from space: New Studies on the Murchison Meteorite Shed Light on the Pre-RNA World
More resources to read: