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A New Recipe for Hunting Alien Life

scientificamerican.com

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Re: A New Recipe for Hunting Alien Life

#31

Post by jcranmer »

poelzi wrote: post #5

The fermi paradox bothered me quite a bit, like all paradoxes and they should bother everybody. They are a flag that something does not add up and there must be some sort of wrong assumption somewhere. As most of our combined "knowledge" does not add up correctly just one example is quantum mechanics and relativity - no, they do not add and therefor need higher dimensions to have a model (a emergency hatch). It is qu…

Fundamentally, there are four main responses to the Fermi paradox:

1. We really are the first.

2. Interstellar communication and travel is effectively impossible.

3. Interstellar communication and travel is possible, but is not executed in a sustained way for various cultural reasons.

4. Alien life exists, but we haven't or can't find it.

All of those explanations are very plausible answers. In fact, the notion that we "ought" to have found alien life by now is itself quite difficult to argue, because it relies on extrapolating estimates from 0 data points (note that we don't know how to become an interstellar species, and it's debatable if we even yet have the technological level to become an interplanetary one).

Re: A New Recipe for Hunting Alien Life

#32

Post by louithethrid »

outworlder wrote: post #21
louithethrid wrote: post #16

Imagine one human probe, with one little algea splash landing in a ocean there. We would be the re-creators of the green goo scenario.

We planetary protection directives, you know.

All those rule books, but it takes just one butt scratch on the way back from the interplanetary probe toilett to unfold this scenario. Poor europe.

Honestly, after seeing those anti-corruption rule books - and on the same homepages where they are displayed, the markers in countrys where you cant to buisness without - sort a contamination scenario in itself, i doubt that anything can prevent this once the dice with the one killing side gets re rolled often enough.

So my money would be on less philosophers employed, more disease-control specialists, which would quickly introduce counter agents that could be consumed by the local flora/fauna.

Re: A New Recipe for Hunting Alien Life

#33

Post by vanderZwan »

JeanSebTr wrote: post #29
vanderZwan wrote: post #13

Earlier quoted context omitted.

> there's no requisite that ATP/ respiration is the direction life is going to take Based on the article I linked in my other comment I would say that on oxygen-rich planets, respiration is likely to happen simply because life needs to find a way to deal with it's toxicity, or perish. Although that presupposes that photosynthesis is inevitable, which also doesn't have to be true. I kind of wonder how much we truly kn…

It would be Life's technical debt :D

Hah, guess it kind of is! Maybe genetic engineering will eventually lead to a huge increase in biodiversity...

Re: A New Recipe for Hunting Alien Life

#34

Post by vanderZwan »

plushpuffin wrote: post #22
plushpuffin wrote: post #20

Earlier quoted context omitted.

As one example on a physical rather than a chemical level, I read that marsupials are stuck for this reason. They need claws to climb into their mother's pouch after birth, so there are certain ecological niches closed off to them. You'll never see a hoofed marsupial, for example.

Found a source: https://synapsida.blogspot.com/2011/11/why-marsupials-cant-f...

I've heard that the cheetah is considered an evolutionary dead end as well, being so hyper-specialised for speed that they are unlikely to be able to keep up the arms race with their prey, nor able to evolve back out of this.

Re: A New Recipe for Hunting Alien Life

#35

Post by jcranmer »

EthanHeilman wrote: post #30
pavel_lishin wrote: post #9

Earlier quoted context omitted.

It's not really a paradox, right? It's just a big equation and we're guessing at the variables.

It is a paradox in the sense that most of the educated guesses result in a universe which is very different from the one we observe. The paradox exists between: 1. the admittedly weak evidence for each of the guesses 2. and the evidence that at least one of the guesses must be wrong.

Calling them "educated guesses" is overstating the evidence. We don't have the datapoints to estimate how common life is or isn't in the galaxy by empiricism, and we don't have the scientific knowledge to derive the numbers from first principles. Divorced from reality, that means that the educated guesses are really "we come up with numbers we want and then bullshit an explanation for those numbers."

Another perspective is that, as we've understood better how our EM radiation percolates for space, radioastronomy basically can't find anyone who isn't in our solar system (except maybe if they directly try to talk to us). That means that even our failure to find life via SETI isn't evidence of anything.

Re: A New Recipe for Hunting Alien Life

#36

Post by EthanHeilman »

jcranmer wrote: post #35
EthanHeilman wrote: post #30

Earlier quoted context omitted.

It is a paradox in the sense that most of the educated guesses result in a universe which is very different from the one we observe. The paradox exists between: 1. the admittedly weak evidence for each of the guesses 2. and the evidence that at least one of the guesses must be wrong.

Calling them "educated guesses" is overstating the evidence. We don't have the datapoints to estimate how common life is or isn't in the galaxy by empiricism, and we don't have the scientific knowledge to derive the numbers from first principles. Divorced from reality, that means that the educated guesses are really "we come up with numbers we want and then bullshit an explanation for those numbers." Another perspect…

>the educated guesses are really "we come up with numbers we want and then bullshit an explanation for those numbers."

tomayto, tomahto. You won't get a strong defense of most of particular values for the drake equation from me. The question that remains is which of our guesses are wrong and why?

>Another perspective is that, as we've understood better how our EM radiation percolates for space, radioastronomy basically can't find anyone who isn't in our solar system (except maybe if they directly try to talk to us).

There are other aspects of the universe that don't agree with common assumptions about how it should appear if it were swarming with technological civilizations with a billion year head start on us. For instance we have yet to detect any stellar/galactic engineering. Then again I'm not particularly convinced by our assumptions about a billion year old technological civilizations.

Re: A New Recipe for Hunting Alien Life

#37

Post by sideshowb »

rthomas6 wrote: post #18

I'm going to try to put into words something about our methods of hunting for alien life that has always bothered me, and I'm probably going to fail. What is intelligence in the context of extraterrestrial life? I posit that we have no good model for what intelligence actually is, and that it makes no sense to assume any alien lifeform would share our goals of seeking knowledge, reproduction, preservation, or "living…

I think schrodinger's entropic definition of life answers most of your questions and is general enough to transcend our own biological oddities.

Still I like https://xkcd.com/638/

Re: A New Recipe for Hunting Alien Life

#38

Post by taeric »

pecg wrote: post #14
taeric wrote: post #10

Earlier quoted context omitted.

I think the problem there is simply the fact that it isn't knowable. If there is a way for life to be that different, how do you look for it? My first statement is likely stronger than it needs to be. My main question back to you is, how do you look for something that you imagine may exist, but couldn't say how?

> My first statement is likely stronger than it needs to be. My main question back to you is, how do you look for something that you imagine may exist, but couldn't say how? I certainly agree with you, thus seeking for life similar than ours is the only feasible way to spend time in deep space research; we cannot look for something different, because we don't know what to look for.

My apologies on the very late response, but if you haven't read it, I recommend the book The Eerie Silence. Covers a lot of this general idea.

https://smile.amazon.com/Eerie-Silence-Renewing-Search-Intel...

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