Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Radical Study Suggests Life on Earth Arose Twice

sciencealert.com

Post reply on HN
Print view View original

121–128 of 128 posts

Re: Radical Study Suggests Life on Earth Arose Twice

#121

Post by 0xDEAFBEAD »

triceratops wrote: post #118
0xDEAFBEAD wrote: post #100

Earlier quoted context omitted.

The Milky Way is almost 14 billion years old. The Milky Way is perhaps 100K light-years in diameter. If you can travel at 0.1c you could colonize the Milky Way in perhaps around a million years, less than 0.01% of the age of the Milky Way. So, either there's a filter that's blocked interstellar colonization... or it has occurred already, and we just aren't aware of it (some sort of dark forest thing / we are being se…

> If you can travel at 0.1c you could colonize the Milky Way in perhaps around a million years There's no reason to believe a civilization is capable of million year projects.

You mean there's some filter which prevents civilizations from developing that capability? ;-)

Re: Radical Study Suggests Life on Earth Arose Twice

#122

Post by triceratops »

0xDEAFBEAD wrote: post #121
triceratops wrote: post #118

Earlier quoted context omitted.

> If you can travel at 0.1c you could colonize the Milky Way in perhaps around a million years There's no reason to believe a civilization is capable of million year projects.

You mean there's some filter which prevents civilizations from developing that capability? ;-)

If lack of interest is a filter, sure. Not an especially alarming one though.

Re: Radical Study Suggests Life on Earth Arose Twice

#123

Post by antonvs »

Asraelite wrote: post #39
binaryturtle wrote: post #36

Earlier quoted context omitted.

I always found it odd that there's only one single origin of life point or even just a single common ancestor considered in history. Shouldn't entirely new life develop all the time on earth? I mean the ingredients and building blocks are still there, the environmental situation still should work out, like availability of water, temperatures, etc. We should see a constant emergence of new life all the time. Why would…

> Shouldn't entirely new life develop all the time on earth? The fact that it doesn't is a pretty simple solution to the Fermi Paradox.

It's probably unrelated to the Fermi Paradox. Life doesn't develop all the time on Earth largely because it's already developed. The conditions for that development are largely gone now, plus existing life easily outcompetes new life in general. This tells us nothing about the probability of the development of new life in an environment that doesn't already have life.

Re: Radical Study Suggests Life on Earth Arose Twice

#124

Post by antonvs »

0xDEAFBEAD wrote: post #100
triceratops wrote: post #72

Earlier quoted context omitted.

The Great Filter is only one possible answer to the Fermi Paradox.

The Milky Way is almost 14 billion years old. The Milky Way is perhaps 100K light-years in diameter. If you can travel at 0.1c you could colonize the Milky Way in perhaps around a million years, less than 0.01% of the age of the Milky Way. So, either there's a filter that's blocked interstellar colonization... or it has occurred already, and we just aren't aware of it (some sort of dark forest thing / we are being se…

These sort of calculations are nothing but examples of how a bad model gives bad results. In this case, the model is bad because it's underspecified.

Saying "I have a bad model but there's some unknown Great Factor which would make it a good model" isn't very convincing.

There are myriad factors: the biological challenges of space travel constitute a long list in itself; the economics and politics involved (ROI on any useful timeframe for interstellar travel is zero); the engineering challenges (the vast majority of interstellar travel attempts will result in the death of all crew somewhere in interstellar space); the fact that over million-year timescales, species evolve and change - humans are only around 30% of a million years old.

Re: Radical Study Suggests Life on Earth Arose Twice

#125

Post by pfdietz »

ck2 wrote: post #71
pfdietz wrote: post #61

Earlier quoted context omitted.

Sorry, when you make an assertion, you don't get to demand I justify questioning it. You need to explain why I should believe you. Your reversal of burden of proof is a red flag that you don't have a good argument. IMO, it is quite plausible that OoL is extremely unlikely and that our solar system is the only place where life occurs in the visible universe. Not proved, of course, but the possibility is by no means un…

wasn't demanding, just wanted to hear what your own logic was instead but it's pointless to go any further I guess as it's getting outside science the weak anthropic principle can't be falsified so it cannot be argued I don't think we'll ever hear from "ET" but I do think it's perfectly plausible to find single-celled or simple bacteria elsewhere someday (ie. Europa, comet or asteroid)

If I were saying we were definitely rare or unique, you'd have an argument.

But I'm not doing that -- I'm saying it's a possibility that is consistent with evidence.

The claim that life is common is different. For that, you really need to present an argument that life being uncommon is ruled out.

In your last sentence there you've retreated from "life is common" to "it's plausible life is common". Sure (within the constraints of the Fermi Argument, but that has uncertainties.)

Re: Radical Study Suggests Life on Earth Arose Twice

#126

Post by pfdietz »

triceratops wrote: post #118
0xDEAFBEAD wrote: post #100

Earlier quoted context omitted.

The Milky Way is almost 14 billion years old. The Milky Way is perhaps 100K light-years in diameter. If you can travel at 0.1c you could colonize the Milky Way in perhaps around a million years, less than 0.01% of the age of the Milky Way. So, either there's a filter that's blocked interstellar colonization... or it has occurred already, and we just aren't aware of it (some sort of dark forest thing / we are being se…

> If you can travel at 0.1c you could colonize the Milky Way in perhaps around a million years There's no reason to believe a civilization is capable of million year projects.

There is no need for an organized, unified project for life to spread across the galaxy, any more than there's a need for a unified effort for bacteria and fungi to consume some tasty organic matter, or for humans to have spread across Earth in prehistory.

Re: Radical Study Suggests Life on Earth Arose Twice

#127

Post by pests »

xkcd1963 wrote: post #103
pests wrote: post #99

Earlier quoted context omitted.

The guidelines do not mention religion a single time. What are you talking about?

"Please don't use Hacker News for political or ideological battle. It tramples curiosity."

I think that is saying something else. It says "battle" not "discussion" or "conversation".

Then if religion is going to be lumped under "ideological battle", what about politics, culture, economics, and other "ideological" topics?

The comment you replied to wasn't even religious. There was a claim that "loving creator" name was invented by people outside the bible, and a claim that theistic evolution is a wide enough belief, esp with Protestants.

I'm not even religious, but those weren't even religious points. Its the difference between "bible history" (history as told by the bible), and "history of the bible" (history of how the bible itself).

Re: Radical Study Suggests Life on Earth Arose Twice

#128

Post by xkcd1963 »

pests wrote: post #127
xkcd1963 wrote: post #103

Earlier quoted context omitted.

"Please don't use Hacker News for political or ideological battle. It tramples curiosity."

I think that is saying something else. It says "battle" not "discussion" or "conversation". Then if religion is going to be lumped under "ideological battle", what about politics, culture, economics, and other "ideological" topics? The comment you replied to wasn't even religious. There was a claim that "loving creator" name was invented by people outside the bible, and a claim that theistic evolution is a wide enoug…

You are right. I came to HN with the desire to make some usefulness out of me, and found the means to do so by policing around, pointing out to the guidelines, flagging random posts, and generally be obnoxious. All with the purpose to raise the standards rather than drag them down on this site. But it turns out I lived long enough to become the villain and if I look now in the mirror I see the very thing I was trying to battle.
Post reply on HN