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Comment by sktrdie | Hacker News Reader

To me beginning of life is a combinatorial issue. You have to have the right combination of lots of different things (chemicals, weather conditions, time etc) to have it happened. What’s scary (or interesting) to me is that we have access to labs and are capable of quickly iterating with lots of different combinations; yet no life arised. If it’s hard in a lab it’s probably a lot harder in nature where to get a different set of combinations you need a new planet! Hence why I think life is rare in the universe.

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Take the volume of all the lab experiments ever done, multiplied by the length of time those experiments were run for.

Next take the entire volume of Earth's primordial oceans and multiply by a few hundred million years, roughly the period during which life arose on Earth.

What's the ratio between those two results? The fact that something arose once in the latter tells you very little about what's happening in the former.

I understand your point, but in the lab scenarios we are theoretically using ideal(ish) conditions (or, at least what we think are ideal conditions).

In the random nature scenario, probably 99% of all the instances would be immediately discarded for potential because of 1 or more clearly suboptimal conditions.

Sure, but even if those ideal conditions only existed in a few cubic KM of ocean for a few million years, and life occurred there once, were never going to replicate that.

If it really was likely to happen in a few litres of chemicals over a few years, once those conditions arose in the early oceans we'd expect it to have happened trillions of trillions of times, not just once or a few times.

On the other hand if the conditions were so rare that they only occurred once in a few litres of ocean for a few days, those conditions must be so specific and unusual that we might never figure out how to create them.

Fermi estimate: there have been 10000 experiments of 10L each for a year. That gives 10000L-years. There are ~10^21 liters of water on the Earth. Let’s say life took a billion years to start. 21+9-4=>10^26x.

Let’s say the labs are 99.999999 “efficient” compared to the oceans. That carved off 8 decades, meaning Earth’s experiment was still a million million million times bigger.

But, as the article points out, the size of the oceans may actually work against that by diluting the possibility of getting the correct concentration of ingredients.

Ok so let’s say the conditions only occurred for one day each year, in a one litre puddle. Over just a one hundred million year period. I think that’s an extremely conservative estimate.

Let’s say I have a huge lab and we have 1,000 one litre experiments running continuously. It would still take me 274 years going non stop to recreate the conditions.

Well I hope the researchers aren't pursuing this randomly.

You include a good countervailing point in your comment, which is that our experiments are largely confined to what we think are ideal conditions. Evolution (or, whatever you want to call this abiotic Darwinian selective process) searches the space of possible designs randomly, which means it can happen on "improvements" that would be hard to predict a priori.

But we don’t really even know what’s “ideal”. If you read the article they go through the stages of achievements in laboratory synthesis of amino acids and proteins. Early work focused on heat and electricity. Later work realized that all you need was wet/dry cycles.

You see we’re still figuring out what the conditions should be. Yes we’re good and recreating specific conditions, but we’re still figuring which ones we should strive for.

Natural of course had the luxury of just trying them, in parallel, over vast amounts of time.

Nature also had the luxury of not even having to try. If the creation of life on Earth had failed, we wouldn't have known about it.

> Next take the entire volume of Earth's primordial oceans and multiply by a few hundred million years, roughly the period during which life arose on Earth.

Multiplied by more than two to the power of each quantum event of a certain type, if the Everret interpretation of quantum mechanics is true.

These other universes weren't observed by our one and who knows what happened there. Including them would be cheating.

If the interpretation is correct, there can indeed be limited interactions between them, or else quantum computing couldn't speed up certain algorithms, so they can indeed have already been observed, but we can't prove it wasn't just through something explained by another interpretation.

I didn't say they couldn't be observed, I said they weren't observed, to the best of my knowledge.

I didn't say I can prove anything about reality, because I decidedly cannot; I simply don't know the axioms.

But over a billion years or so, vastly more conditions occur on a single planet than we could ever hope to replicate in a lab, and even with the right conditions it might just be unlikely and take a very long time. So I’m still optimistic despite this argument.

Not to detract on your conclusion (I do think like is hard due to some estimates on chemical combinations), but there are way more planets than experiments on Earth about abiogenesis.

Imagine that in each pond several different combinations are being tried in parallel, kind of like in a quantum computer. Of course, the universe is a giant quantum computer. This leads to the idea that even if life is very unlikely, it can still develop since there are so many "attempts". It also means that life can develop many times, but in different attempts. By this I mean different parallel attempts, such that whatever happens in one of these attempts is not accessible to what happens in another attempt.

I also think life is very rare, and I am in fact of the opinion we won't find any other instance of it.

The thing I always struggled with about the "Monkeys at typewriters" type thinking is what about entropy?

Yes with unlimited attempts anything can happen but if you have a force working against it, it could also be equally likely nothing ever happens, it forever remains neutral or not enough time (if a universe has a life span).

Indeed. One thing labs lack that the early earth had in the plenty is space (for multiple "experiments") and time.

Can we make an earthquake in a lab?

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