61–70 of 134 posts
> Carell, an organic chemist, and his collaborators have now demonstrated a chemical pathway that — in principle — could have made A, U, C and G (adenine, uracil, cytosine and guanine, respectively) from basic ingredients such as water and nitrogen under conditions that would have been plausible on the early Earth. The reactions produce so much of these nucleobases that, millennium after millennium, they could have a…
These abiogenesis experiments are a little strange... they aim to show that something could have happened. Whether that is what actually happened is considered less relevant and in fact can probably never be determined. Does anyone really believe that it is impossible to get spontaneous nucleotide generation under certain conditions (the conditions also being speculative)? The really interesting thing would be findin…
> Carell, an organic chemist, and his collaborators have now demonstrated a chemical pathway that — in principle — could have made A, U, C and G (adenine, uracil, cytosine and guanine, respectively) from basic ingredients such as water and nitrogen under conditions that would have been plausible on the early Earth. The reactions produce so much of these nucleobases that, millennium after millennium, they could have a…
I agree, but keep in mind abiogenesis is probably one of the tallest orders for chemistry. I'm glad scientists are at least exploring possible explanations, even if it means possibly disproving the mechanisms.
Earlier quoted context omitted.
There's a multiverse theory that there are many possible or existing universes with different physical constants, affecting everything from chemistry to orbital mechanics, and the reason we are having this conversation is because this universe was conducive to the formation of highly organized lifeforms capable of abstract thought. In this line of reasoning "Why this set of constants" doesn't matter, because only the…
The anthropic principle doesn't depend on a multiverse.
That is to say, we may not be able to easily predict and rationalize the beginning of life based on the initial conditions of the earth, because it is likely that it was an improbable fluke. It feels like a lottery winner trying to explain how they won the lottery.
Not sure where I saw it. hackernews? Might have been Scientific American.
I anyone remembers I would appreciate a link.
>The chemistry is also a “strong indication” that the appearance of RNA-based life was not an exceedingly lucky event, but one that is likely to happen on many other planets, he adds. Does this mean a new lower bound for the fl factor for the drake equation ?
That "strong indication" comment is BS.
Reminds me of the Miller-Urey experiment, except Miller and Urey didn’t find amino acids that could form DNA or RNA. https://en.wikipedia.org/wiki/Miller%E2%80%93Urey_experiment
Earlier quoted context omitted.
Sure, I guess. But we've been down this road of chemical soups before ~ and gotten nothing out of it. I'm just frustrated that they seem to keep chasing the same failed ideas. It's time to look for other explanations... not a religious one, at that. Some biologists look towards a meteoric explanation of life, but punting it off-planet isn't an explanation, either...
I don't think the idea is failed. Yes, attempts to replicate it in laboratory-scale tanks haven't succeeded yet. But that isn't evidence against the theory that it occurred sometime over millions of years in billions of cubic kilometers of water. It happens at some statistical rate, and lab experiments so far have put an upper bound on the rate.
Most here seem to reason the other way around - it must have happened, so we'll just keep looking until we figure out how. I'd like to think that we could reach a point at which we could confidently say "this universe doesn't have the probabilistic resources to make it happen" instead of kicking the can down the road indefinitely.
Has anyone proven that the "soup" has to be liquid? I'm no chemist, but I was curious one day so I looked through the chemical composition of humans, and was surprised to see that almost all of the base elements from the periodic table that we are composed of are lighter than air. Just ran the numbers again for this post: ~96.2% oxygen,hydrogen,nitrogen,carbon ~ 3.8% calcium,phosphorus, potassium,sulfur,sodium, chlor…
This is almost completely gibberish since you don't find atoms in isolation.