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Earth was born dry until a cosmic collision made it a blue planet

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Re: Earth was born dry until a cosmic collision made it a blue planet

#261

Post by runarberg »

pfdietz wrote: post #260
runarberg wrote: post #256

Earlier quoted context omitted.

von Neumann probes are a fantasy. I see no reason why any civilization in the entire universe will ever build a successful self replicating probes, let alone ones that are still replicating dozens of millennia later. The reasons include that targeted probes and telescopes can give you pretty much the same amount of knowledge for far cheaper and much quicker then random walking probes across the galaxy. There is also…

> von Neumann probes are a fantasy. Well pack it up folks, we've been told what would be possible for any alien civilization, even given millions of years of effort.

Yes, theorizing a future possibility that has no president is, by definition, fantasy. I mean, you can do fantasy, it makes good science fiction, but until we have evidence that von Neumann probes exist and are capable of colonizing the entire galaxy, it remains fantasy. Theoretically we could build a high speed rail between Seattle and LA, we could build a permanent settlement on Antarctica, and we could replace our jet-planes with hydrogen powered flying wings, but until we do, a world with those things are just fantasy.

The only argument for von Neumann probes that I can think of is as a specific answer to the Fermi paradox. The universe should be filled with these probes, but since it obviously isn’t, we can infer that no civilization has reach the interstellar age.

I reject this framing, the Fermi paradox is only a paradox if you assume that space colonization is a thing that is not just possible, but inevitable. My solution to the Fermi paradox simply rejects this assumption. Civilization will not colonize definitely, they will do their space explorations with telescopes and targeted probes, and they won‘t build any von Neumann probes (at least not ones continue to replicate for dozens millennia).

Aside: I am aware of the irony that my description of civilizations outside of our solar system is also a fantasy.

Re: Earth was born dry until a cosmic collision made it a blue planet

#262

Post by littlestymaar »

corimaith wrote: post #255
littlestymaar wrote: post #250

Earlier quoted context omitted.

Also, people vastly underestimate how hostile space is: colonizing Mount Everest, the Antarctic or the continental plateau under sea would be far easier than colonizing Mars. And Mars is the most hospitable extraterrestrial place we know of.

I don't think we would colonizing Mars, free floating colonies akin to O'Neil Cylinders orbiting Earth would probably be the more logical option. And with increasing robotic automation capabilities, it's not improbable to see these being built in the future.

Having the technology to build it isn't the hard part. The question is why you'd do that in the first place and who would fund such a colony.

First of all it's going to be massively more expensive than any housing we've ever built on earth so only a very small elite could afford living there.

But then again, space is a very hostile environment: it's super dangerous (any incident will almost certainly snowball into a dramatic accident), very unhealthy (billionaires are currently funding longevity research, so I don't think they'd like to go in a place where they would age up significantly faster than on earth…), and life is just worse up there on all respect…

Re: Earth was born dry until a cosmic collision made it a blue planet

#263

Post by antonvs »

corimaith wrote: post #255
littlestymaar wrote: post #250

Earlier quoted context omitted.

Also, people vastly underestimate how hostile space is: colonizing Mount Everest, the Antarctic or the continental plateau under sea would be far easier than colonizing Mars. And Mars is the most hospitable extraterrestrial place we know of.

I don't think we would colonizing Mars, free floating colonies akin to O'Neil Cylinders orbiting Earth would probably be the more logical option. And with increasing robotic automation capabilities, it's not improbable to see these being built in the future.

> it's not improbable

"Extremely improbable" would be a better assessment.

Even ignoring the project complexity, difficulty, and energy budget, which can't simply be handwaved away by "robotic automation", one reason is simply that such colonies don't solve any problem that we're likely to have, that can't be solved much more cheaply, safely, and effectively.

But even the idea that we'll eventually have the technology to build such structures is debatable. Will this be before or after we solve climate change, for example? Because that issue is likely to severely impact our technological capabilities over the timescales involved. And as of today, the most technologically advanced nation is doubling down on atmospheric carbon production.

Re: Earth was born dry until a cosmic collision made it a blue planet

#264

Post by antonvs »

lazide wrote: post #254
antonvs wrote: post #237

Earlier quoted context omitted.

An obvious line would be when copyright expires. In fact, drawing that line is exactly what copyright expiry is intended to do.

Copyright has far exceeded sane limits a long time ago.

What's a "sane" point at which you become entitled to other people's work?

Re: Earth was born dry until a cosmic collision made it a blue planet

#265

Post by squigz »

antonvs wrote: post #264
lazide wrote: post #254

Earlier quoted context omitted.

Copyright has far exceeded sane limits a long time ago.

What's a "sane" point at which you become entitled to other people's work?

What a strange way to phrase it, considering in your last comment you were talking about how copyright expiry is exactly for this purpose.

Anyway, what is copyright expiration in America these days? 100 years?

Also, is it simply a matter of X years after creation? I somehow doubt it's that simple anymore. I wouldn't be surprised if "copyright is extended indefinitely if the work is being actively commercially used" or some such

Re: Earth was born dry until a cosmic collision made it a blue planet

#266

Post by lazide »

squigz wrote: post #265
antonvs wrote: post #264

Earlier quoted context omitted.

What's a "sane" point at which you become entitled to other people's work?

What a strange way to phrase it, considering in your last comment you were talking about how copyright expiry is exactly for this purpose. Anyway, what is copyright expiration in America these days? 100 years? Also, is it simply a matter of X years after creation? I somehow doubt it's that simple anymore. I wouldn't be surprised if "copyright is extended indefinitely if the work is being actively commercially used" o…

Patents are for 15-20 years.

Which is saner eh! That way people living at the time who are protecting it (copyright and patents are both protections for things otherwise being distributed and which could be copied easily) can benefit from it eventually.

100 years is just rent extraction.

Re: Earth was born dry until a cosmic collision made it a blue planet

#267

Post by lazide »

DennisP wrote: post #258
lazide wrote: post #241

Earlier quoted context omitted.

Probability distributions based on a single data point (of where we know there is life) aren’t reliable distributions.

Which is why they set very wide ranges on the things we know little about. Doing that is less unjustified than guessing specific values, as people have usually done. It's nowhere near a precise estimate of the probability of life. What it mainly shows is that the Fermi "paradox" is no such thing. It can look that way if we guess specific parameter values, but if we fully account for our uncertainty on the various par…

I’m not saying precise. I’m saying it isn’t even an estimate.

You can’t have a distribution with one data point.

It’s similar to the arguments about 3I/Atlas being an alien spacecraft because it’s so ‘weird’.

With so few data points, everything is fundamentally ‘weird’ - or normal - we have no way to tell, so making any sort of statistical argument about it is fundamentally useless and misleading, as statistics is based on groups. And we don’t have a group yet.

Re: Earth was born dry until a cosmic collision made it a blue planet

#268

Post by DennisP »

lazide wrote: post #267
DennisP wrote: post #258

Earlier quoted context omitted.

Which is why they set very wide ranges on the things we know little about. Doing that is less unjustified than guessing specific values, as people have usually done. It's nowhere near a precise estimate of the probability of life. What it mainly shows is that the Fermi "paradox" is no such thing. It can look that way if we guess specific parameter values, but if we fully account for our uncertainty on the various par…

I’m not saying precise. I’m saying it isn’t even an estimate. You can’t have a distribution with one data point. It’s similar to the arguments about 3I/Atlas being an alien spacecraft because it’s so ‘weird’. With so few data points, everything is fundamentally ‘weird’ - or normal - we have no way to tell, so making any sort of statistical argument about it is fundamentally useless and misleading, as statistics is ba…

We know a lot more than the simple fact that civilization exists on our planet. See section 3 for how they estimated the parameters.

One of the most uncertain parameters is the rate of abiogenesis events per planet. For that one they used a log-normal with a standard deviation of 50 orders of magnitude. They discuss specific theoretical limits from biology for both ends of the range.

Compared to this approach, the usual method is to just pick particular values out of a hat. This paper at least improves that by directly representing our vast uncertainty for some of the values.

It doesn't tell us how many alien civilizations there are. But it does tell us the range of possibilities, given what we know and don't know.

Re: Earth was born dry until a cosmic collision made it a blue planet

#269

Post by lazide »

DennisP wrote: post #268
lazide wrote: post #267

Earlier quoted context omitted.

I’m not saying precise. I’m saying it isn’t even an estimate. You can’t have a distribution with one data point. It’s similar to the arguments about 3I/Atlas being an alien spacecraft because it’s so ‘weird’. With so few data points, everything is fundamentally ‘weird’ - or normal - we have no way to tell, so making any sort of statistical argument about it is fundamentally useless and misleading, as statistics is ba…

We know a lot more than the simple fact that civilization exists on our planet. See section 3 for how they estimated the parameters. One of the most uncertain parameters is the rate of abiogenesis events per planet. For that one they used a log-normal with a standard deviation of 50 orders of magnitude. They discuss specific theoretical limits from biology for both ends of the range. Compared to this approach, the us…

Except we don’t actually know the real ranges of values here, so our actual level of uncertainty is still infinite.

Re: Earth was born dry until a cosmic collision made it a blue planet

#270

Post by DennisP »

lazide wrote: post #269
DennisP wrote: post #268

Earlier quoted context omitted.

We know a lot more than the simple fact that civilization exists on our planet. See section 3 for how they estimated the parameters. One of the most uncertain parameters is the rate of abiogenesis events per planet. For that one they used a log-normal with a standard deviation of 50 orders of magnitude. They discuss specific theoretical limits from biology for both ends of the range. Compared to this approach, the us…

Except we don’t actually know the real ranges of values here, so our actual level of uncertainty is still infinite.

If your level of uncertainty is infinite then you're suggesting that abiogenesis could be happening every day in your back yard. I think you might admit we're a little more certain than that.
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