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Aliens on 1k nearby stars could see us, new study suggests

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Re: Aliens on 1k nearby stars could see us, new study suggests

#221

Post by Retric »

mylons wrote: post #218
Retric wrote: post #208

Earlier quoted context omitted.

Building something with zero possibility of change across millions of years is difficult. Something as simple as reproducing endlessly means they end up wasting enormous amounts of resources. But, you also risk things like probes that don’t slow down and hit one of your planets.

Sure, but we’re now beginning to talk about infinite scale and infinite resources. Who cares if 1 planet doesn’t produce probes as fast or at all? Who cares if 1 probe slams through a planet? That being said, I think the latter case might be more controllable by a civilization capable of creating the machines?

The fear is that you destroy one or more of your inhabited planet not just a lifeless ball. Which I would hope you and most people would consider a significant downside. That risk is balanced vs the benefit of sending self replicating probes to every star system which just doesn’t seem that useful.

Now is that a large or small risk? I don’t have the technology but it’s something that could reasonably concern a civilization.

Re: Aliens on 1k nearby stars could see us, new study suggests

#222

Post by nlh »

sosborn wrote: post #120
jessaustin wrote: post #78

Earlier quoted context omitted.

I've never forgotten the scene in the OSC short story "Fat Farm", in which the protagonist's mind has been copied to his clone, which clone has left the facility to "continue" to enjoy his fine life, and the protagonist realizes he hasn't thought about what comes next. The answer is grim. A consciousness might awake in the machine, but it won't be my consciousness.

But for the consciousness in the machine, does that distinction matter at all?

I think about this a lot. The answer, I think, is No, the distinction does not matter.

The consciousness in the machine will think "Wow this worked!" and go on with life in the machine. The original consciousness (you) will say "well that was dull - look at that machine consciousness having all the fun inside the machine."

But now extend the metaphor. Is there really any difference - in your perspective as the original consciousness - between the consciousness in the machine (your copy) and the consciousness next to you? (Your wife, husband, friend, brother, or sister). Or the consiousness across the street? Or any other consciousness that's not you? Each has its own set of memories that gives it a sense of self. Each sees the world outward from its own perspective.

So really, is there any difference at all? Either they're all totally different...or maybe they're all the same......

Re: Aliens on 1k nearby stars could see us, new study suggests

#223

Post by tsimionescu »

tzs wrote: post #137
tsimionescu wrote: post #86

Earlier quoted context omitted.

There are problems of resiliency and energy storage that could be more or less fundamental problems. It could take millions if years of technological civilization to produce a machine capable of sustaining life for the hundreds of thousands of years necessary for interstellar travel, and civilizations may tend to collapse for various reasons before reaching such technological peaks. It's also entirely possible that w…

> It could take millions if years of technological civilization to produce a machine capable of sustaining life for the hundreds of thousands of years necessary for interstellar travel. For a generation ship, are you referring to all the machinery that can maintain a balanced ecosystem of plants and animals and humans in order to provide food for the people during the trip to the new planet, and to make all the thing…

I am referring to all of the machinery on the ship in general - whether it's life support systems, engines, monitoring/navigation systems etc. Even if you could take a ship to outer space, freeze it to ~absolute 0, and launch it on its trajectory, you still need a computer to allow it to warm back up and land at its destination.

Keeping a computer running in outer space for a few thousand or hundred thousand years is a gigantic engineering task, far beyond anything we could achieve today.

And of course, in reality its unlikely you could rely on a single computer system and on 0 propulsion. It's far more likely that you'll need life support, engines, complex medical equipment, cooling systems, lights, all sorts of mechanical parts that will need power, replacements, and that degrade in time, especially at such huge scales.

Re: Aliens on 1k nearby stars could see us, new study suggests

#224

Post by tsimionescu »

sliken wrote: post #192
tzs wrote: post #137

Earlier quoted context omitted.

> It could take millions if years of technological civilization to produce a machine capable of sustaining life for the hundreds of thousands of years necessary for interstellar travel. For a generation ship, are you referring to all the machinery that can maintain a balanced ecosystem of plants and animals and humans in order to provide food for the people during the trip to the new planet, and to make all the thing…

Seems a bit silly, you can buy a glass sphere with small closed ecosystem that can last years with indirect sunlight. Surely we can manage something that recycles astronaut poop/pee into something vaguely edible with the help of bacteria, fungus, plants, and algae. Sure some genetic editing (of humans, bacteria, fungus, plants, and algae) might be necessary. Even just some minor tweak like happened in the last 1000s…

That is taking energy from the sun, and it is relying on the Earth to maintain certain temperature parameters. It won't last 10k years anyway. If nothing else, the glass will probably degrade over a long enough period of time. There's also a constant chance of a freak mutation destroying the equilibrium of the system.

In outer space, cosmic rays will make this process faster. Also, in outer space, it will need a constant source of light for biological reactions, and also just to keep from slowly cooling down to 0k through heat emission.

Re: Aliens on 1k nearby stars could see us, new study suggests

#225

Post by qes »

tsimionescu wrote: post #207
rsynnott wrote: post #143

Earlier quoted context omitted.

Hmm, I'm not sure that that's correct. If you build an apartment block and it catches fire the week afterwards, then it's perhaps not reasonable to expect that if you build another one to exactly the same design it will never catch fire. At that point you might want to be reviewing your wiring plans. That life showed up so early says... something. If life showing up was so fantastically difficult, we would arguably e…

Sure, but if you look at an extremely old building and find signs of fire only from its very early age, it's somewhat strange to say that it was very likely to catch fire.

Life on earth isn't an apartment building.

What if you could only tell if the building had ever caught fire and how long ago it first caught fire? You can't tell how many times it caught fire, or when the last time was, or how many times it almost caught fire but didn't, or if it would've caught fire later but only didn't because it had already caught fire before.

Re: Aliens on 1k nearby stars could see us, new study suggests

#226

Post by undersuit »

mod wrote: post #96
saas_sam wrote: post #95

Earlier quoted context omitted.

Is "life only appeared once on earth" an accepted fact at this point? There was clearly at least one occurrence that led to a subsequent successful reproductive pattern from which we evolved, but prior to that, or alongside that, it strikes me as pretty unlikely that we would be able to discover other fleeting abiogenesis events. We just discovered new salivary glands in human heads. Organs. Not microscopic ones. The…

Not to mention it could have started and been scarfed up by already established life. It didn't have to be long-lasting to have happened.

An abiogenesis event being snuffed out by another abiogenesis event... that's like alien invasions.
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