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The Fermi paradox revisited: Technosignatures and the contact era

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Re: The Fermi paradox revisited: Technosignatures and the contact era

#61

Post by Hizonner »

izzydata wrote: post #54
douglaswlance wrote: post #13

If we assume alien life in the universe is predatory and seeks to consume other life forms, and since the universe allows detection from other species over infinite distances and time scales, we would expect life in the universe to either be totally undetectable or else be consumed by life that is totally undetectable.

If you are talking about a dark forest then it is more opf the idea that any other sufficiently advanced civilization would simply destroy you as soon as you are known to them rather than attempting to consume any potential resources you have as that isn't economical. The most economical thing could be as simple as sending a small object at light speed through your sun to cause a supernova. This eliminates you as a p…

While your main point stands, I doubt that crashing even a moderately sized planetoid into a star at any achievable speed would do much to that star. It definitely wouldn't cause a normal supernova.

You might be able to produce some nasty radiation/ionized crap/relativistic debris that would be unpleasant for that greenish scum clinging to some of the planets, but it'd be a really expensive way to do even that.

Sure, if you get close enough to C, you can deliver as much energy as you want, but you're probably going to use the energy of several stars to get a small object going fast enough to deposit a really destructive amount of energy into a single star.

Efficiency is part of finesse...

Re: The Fermi paradox revisited: Technosignatures and the contact era

#62

Post by ben_w »

chii wrote: post #8
antirez wrote: post #5

The first alien we will ever encounter is likely a neural network we built with our hands.

But that wouldn't technically be an alien, since it's not extra-terrestrial.

"Alien" doesn't only mean "extra-terrestrial", for example: https://travel.state.gov/content/travel/en/us-visas/immigrat...

And: https://www.theguardian.com/society/2013/dec/12/gender-segre...

Re: The Fermi paradox revisited: Technosignatures and the contact era

#63

Post by bnralt »

tsimionescu wrote: post #55
bnralt wrote: post #53

Earlier quoted context omitted.

There are ~2 x 10^9 stars in the solar system. The mass of earth is 6 x 10^24 kilos, with about 1/3 of that being iron. So even if we're just using the mass of a single celestial object the size of the earth, and only looking at iron alone, that'd be 1,000,000,000,000,000 kilos of iron you could use per star (for reference, this would be the equivalent of ~300 million fully fueled Saturn V's per star). It seems like…

I am quite certain that using all of the iron in a single planet's core is well beyond the difficulty of building a self-replicating probe (which itself is well beyond our technical capabilities). Not to mention, such probes are unlikely to be build able from a single metal, and some metals used for advanced electronics are significantly rarer than iron.

If you want to restrict yourself to the earth's crust, that'd still be ~5,000,000,000,000 kilos of iron you could use per star, or 1,500,000 Saturn V's. And that's just using one planet.

Sure, there are rarer metals. But I'm not seeing evidence that the solar system wouldn't have enough of them, and mass mining and manufacturing seems like an far easier way to handle them than individual probes (the probe would have to land on the various planets, manufacture refueling centers to refuel itself to travel around the planet doing geological survey and take off again, build mining centers when it finds the deposits, etc.).

Re: The Fermi paradox revisited: Technosignatures and the contact era

#64

Post by 1970-01-01 »

cartercwchen wrote: post #24

I prefer the Dark Forest interpretation of the Fermi Paradox: https://en.wikipedia.org/wiki/Dark_forest_hypothesis

The question of what to do if we're blasted with an artificial signal could be the most important decision ever made.

Re: The Fermi paradox revisited: Technosignatures and the contact era

#65

Post by Hizonner »

YurgenJurgensen wrote: post #41
bnralt wrote: post #15

Earlier quoted context omitted.

I've been wondering what the advantage of von Neumann probes are. Once you have the ability to autonomously construct probes, it seems like it would be easier and faster to mass produce them in one solar system and send them directly to their destinations. For instance, with a von Neumann probe you have to have probes with additional mass for self-replication, have it accelerate halfway to point A, decelerate halfway…

If the probes don't have replication devices in them, what are they doing? The main point of the von-Neumann strategy is that if you don't build a self-replicating hegemonic swarm object, someone else will (whether that be an alien or merely someone else in your own society), and despite what science fiction movies would like to have you believe, you don't win in a war against the Replicators.

> if you don't build a self-replicating hegemonic swarm object, someone else will

Why do I care?

Re: The Fermi paradox revisited: Technosignatures and the contact era

#66

Post by actionfromafar »

1970-01-01 wrote: post #25

Until SETI locates something like a pulsar braking and accelerating to signal prime numbers we're really really really unlikely to stumble onto more life. Space is just too big.

I think it can be done cheaper than that, and with technology we have access to.

Detonate a handful of large hydrogen bombs in deep space, set apart by minutes. Say hello to our fellow Aliens.

Re: The Fermi paradox revisited: Technosignatures and the contact era

#67

Post by fawadasaurus »

1970-01-01 wrote: post #25

Until SETI locates something like a pulsar braking and accelerating to signal prime numbers we're really really really unlikely to stumble onto more life. Space is just too big.

Agreed. I read somewhere that if you pick a random direction and fly through space, you have a 0% chance to ever hit anything.

That is how big and empty the universe is.

Re: The Fermi paradox revisited: Technosignatures and the contact era

#68

Post by cortic »

marcosdumay wrote: post #43
causality0 wrote: post #36

The universe we find ourselves in isn't very compatible with a species like our surviving for an extended period. If humans exist for millions of years we're going to either spread out to fill the galaxy or our machines will. The fact earth was free to develop us means that no other species like us existed long enough to beat us to it. We ought to hope that's because species find some other priority besides expansion…

> because otherwise the reason we're free to exist is because species like us always wipe themselves out before they spread That's a complete non-sequitur. There can be plenty of reasons for a species like us never appearing on the first place, and they are way more reasonable than postulating that life like us always destroy itself.

We are actually running out of places in our history to fit a great filter. Most of the events in our evolution seem probable, even inevitable. In fact the only place IMO that's really left is the emergence of the first self replicating RNA molecule. But even that seems too probable to be a great filter.

And if its not behind us, it has to be in-front of us or we are under a great misapprehension about the nature of the universe.

Re: The Fermi paradox revisited: Technosignatures and the contact era

#69

Post by borbulon »

If I were an advanced civilization with some sort of jump technology, I'd have probes jump to different solar systems for only a few milliseconds, which would be more than enough time to collect technosignatures. I wouldn't wait to for the technosignatures to come to me.

Re: The Fermi paradox revisited: Technosignatures and the contact era

#70

Post by YurgenJurgensen »

Hizonner wrote: post #65
YurgenJurgensen wrote: post #41

Earlier quoted context omitted.

If the probes don't have replication devices in them, what are they doing? The main point of the von-Neumann strategy is that if you don't build a self-replicating hegemonic swarm object, someone else will (whether that be an alien or merely someone else in your own society), and despite what science fiction movies would like to have you believe, you don't win in a war against the Replicators.

> if you don't build a self-replicating hegemonic swarm object, someone else will Why do I care?

If you've achieved enlightenment and freedom from all desire, then it's a bit weird that you're posting on Internet forums. If not, presumably you'd quite like to not be turned into a paperclip.
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