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Grabby Aliens (2021)

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Re: Grabby Aliens (2021)

#91

Post by iraqmtpizza »

GavinB wrote: post #10

This is a compelling theory, especially the implication that humans are early. I do wonder whether we should see the evidence of spheres of growing alien influence out in the stars, but instead we see a highly uniform universe in all directions. This would indicate a few possibilities: 1. Expanding alien civilizations are relatively low impact and don't collect all of the energy of stars in ways that are visible to o…

All evidence says that humans stand alone in the galaxy.

Everything else is cope.

Re: Grabby Aliens (2021)

#92

Post by MrScruff »

behringer wrote: post #33
pavel_lishin wrote: post #30

> that early deadline explains human earliness. I don't buy these statistical arguments. If only one sentient species is born before 20 billion years have passed since the big bang, and ten million sentient species are born after that time, yes - statistically, you're more likely to be one of the later species. But that early worm species still exists, and experiences its existence. If they thought to themselves, "ob…

20 billion is a long time, and the universe is very big. And we're not the first galaxy to form within that 20 billion year time frame. It's very likely we're not the first in the universe and it's also likely we're not alone in coming to sentience at this very moment in the universes life.

What I don't understand is how we reasonably quantify the probability of sentient life evolving. Sure the universe is very big, but the probability could be very small. All the discussions I've seen make the assumption that there's nothing unusual about life on Earth and given similar conditions elsewhere we would expect to see life, but how does one conclude that from a sample size of 1?

Re: Grabby Aliens (2021)

#93

Post by qnleigh »

I'm confused by the argument here; is the argument that 'humanity could not arise once the universe has been taken over by grabby aliens, so a possible explanation of finding ourselves existing so early in the history of the universe is that this will be the only opportunity'?

But if the universe will soon be filled with gajillions of grabby aliens, who's to say that we couldn't have been born as grabby aliens instead of humans? In fact if there will be so many of them, isn't the fact that we're not grabby aliens ourselves evidence that there will be no grabby aliens?

I feel like there is some implicit assumption about 'who you are likely to be born as' that I'm not getting here. Do I need to assume that I could only have been born as a human for the argument to go through?

Re: Grabby Aliens (2021)

#94

Post by qnleigh »

MrScruff wrote: post #92
behringer wrote: post #33

Earlier quoted context omitted.

20 billion is a long time, and the universe is very big. And we're not the first galaxy to form within that 20 billion year time frame. It's very likely we're not the first in the universe and it's also likely we're not alone in coming to sentience at this very moment in the universes life.

What I don't understand is how we reasonably quantify the probability of sentient life evolving. Sure the universe is very big, but the probability could be very small. All the discussions I've seen make the assumption that there's nothing unusual about life on Earth and given similar conditions elsewhere we would expect to see life, but how does one conclude that from a sample size of 1?

I guess the argument is something like 'if life is unlikely to evolve, then it is surprising to find ourselves existing so early in the history of the universe. If life is likely to evolve, then how do we explain being apparently alone?' and then the grabby aliens theory tries to answer the second question.

I don't find the argument convincing though (per my other comment)

Re: Grabby Aliens (2021)

#95

Post by whizzter »

XorNot wrote: post #73
cwillu wrote: post #67

Earlier quoted context omitted.

Alas, there's a fifth possibility: 5. Controlled transportation between the stars, sufficient for colonization, is sufficiently impractical that there are no grabby aliens within our light-cone.

That itself would be quite interesting though, because based on what we know now it's merely difficult, not impossible with reasonably foreseeable technological improvements. The dynamics which would make it impossible on any known timespan don't seem currently observable.

I think a huge factor you don't account for here is that some of these technological improvements might imply a great-filter that we really haven't passed yet as humans, and the negative effects would affect most similarly expansionist and competitive races alike us since it might be questionable if there would be enough pressure on a non-competitive race to expand rather than just conserve local resources.

Just with state-controlled nuclear weapons we've been on the brink of extinction a couple of times already, the energy levels required for star-travel implies this kind of destructive power being in the hands of even more people (and by necessity more or less out of control of the nation states). A commercial airliner took down WTC, a starship would be an WMD capable of taking out a city (or more).

One implication of this is that there's a chance that we've already invented practical fusion power, but if it's trivial to miniaturize AND weaponize then people in control of it have decided to withhold it to avoid every weird terrorist group creating one.

Re: Grabby Aliens (2021)

#96

Post by mjevans »

lostemptations5 wrote: post #77
XorNot wrote: post #74

Earlier quoted context omitted.

I do keep hoping we get lucky in my lifetime and a massive, water bearing comet with slam into Mars and jumpstart the terraforming. Watching a planet which could retain water go from "nothing to oceans" would be amazing.

Evidence suggests Mars had oceans before and they just evaporated due to the thin atmosphere and non-existant magnetic field no? I'm not sure how that would get solved without some active technological solution by humans let's say.

I'm not sure which is more practical. Diverting enough material to replicate earth's natural magnetic core system on mars into the planet, or building an artificial system. The knowledge gained from attempting either is likely valuable.

Re: Grabby Aliens (2021)

#97

Post by ionwake »

kiba wrote: post #68
ionwake wrote: post #36

Earlier quoted context omitted.

Not really I disagree. With software that encourages emergent behaviour we are unaware of the abilities the entities take on. So in theory I think we could.

They can just simply pause, delete, reverse, or make us outright ignore anything. They are literal god and hold ultimate power over us, unless they are willing to deliberately let things happen. The better question is if it even matter.

Im sure it matters, or else we wouldnt exist. How "much" we matter is the question.

Re: Grabby Aliens (2021)

#98

Post by pfdietz »

willis936 wrote: post #89
GavinB wrote: post #10

This is a compelling theory, especially the implication that humans are early. I do wonder whether we should see the evidence of spheres of growing alien influence out in the stars, but instead we see a highly uniform universe in all directions. This would indicate a few possibilities: 1. Expanding alien civilizations are relatively low impact and don't collect all of the energy of stars in ways that are visible to o…

The problem with option 3 is that even a small drop below light speed becomes a large multiplier when looking at galactic and intergalactic distances. Let's say you can manage 0.5 c (pushing far beyond any current physical understanding of what is possible), that means we would have up to a 40,000 year heads up on an approaching galactic civilization. Even if it was 0.9c we would have up to 8,000 years notice. Even w…

Given that the universe is 13.8 billion years old, 40,000 years is nothing.

The presumption that other putative galactic civilizations start at nearly exactly the same time as us is implausible, especially considering more than 9 billion years passed before the solar system even formed.

Re: Grabby Aliens (2021)

#99

Post by pfdietz »

Mistletoe wrote: post #71
XorNot wrote: post #65

Earlier quoted context omitted.

Rather depends on other factors though: you can perfectly well run an interstellar empire with very long communication times and people going into suspended animation for transit. Control strategy simply has to adapt accordingly: i.e. a message probably comes with a fleet sufficient to ensure its obeyed. This was one of the ideas in the Doom novelizations: that the aliens had spent so long travelling that there was l…

Suspended animation may be as impossible as faster than light travel.

Much more plausible, IMO.

Re: Grabby Aliens (2021)

#100

Post by pfdietz »

sevensevennine wrote: post #39
Veserv wrote: post #37

Earlier quoted context omitted.

The hypothesis goes: I want humans to be casually interstellar and expand across the galaxy. I want this to occur in less than N years, N If humans are casually interstellar and expansionist, then we would colonize the galaxy in M years, M Humans are not special, therefore if another alien species existed in the past at current human tech levels, then they would do the same as humans would and colonize the galaxy wit…

I don't follow the last point in your argument. Isn't 4 equivalent to, 'no civilization will invent casual interstellar travel/spread to the stars'? And isn't that hypothesis extremely likely, given what we now know about the costs of _interplanetary_ travel and its relative ease compared to interstellar travel? That's another assumption, that it's _possible_ to colonize a galaxy from a planetary base. We don't even…

> And isn't that hypothesis extremely likely, given what we now know about the costs of _interplanetary_ travel and its relative ease compared to interstellar travel?

Costs are a function of manufacturing productivity. What is the upper bound on manufacturing productivity? With automation and AI, I don't see any hard upper bound.

The raw resources are certainly available to build starships. I mean, your share of per capita energy consumption over your life would be enough to accelerate your body to maybe 700 km/s, and that's with us just using a small fraction of the energy available on a planet; energy in space would be many orders of magnitude more abundant.

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