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Grabby Aliens (2021)

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Re: Grabby Aliens (2021)

#131

Post by not_the_fda »

iraqmtpizza wrote: post #91
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.

I don't think we are alone. We are just separated by enormous amount of distance, and inter-solar system travel isn't feasible.

Re: Grabby Aliens (2021)

#132

Post by gcanyon »

In case anyone is interested in how grabby aliens (or we!) could travel the galaxy, Kurzgesagt has an excellent video on building a stellar engine to move our solar system at up to 50 light years per million years. Setting aside considerations of whether we'll survive the next few decades as a technological civilization, let alone the next few millions of years, the Caplan engine would let us colonize a significant fraction of the galaxy within a billion years or so.

https://www.youtube.com/watch?v=v3y8AIEX_dU

Re: Grabby Aliens (2021)

#133

Post by mattashii »

zare_st wrote: post #128
yreg wrote: post #115

Earlier quoted context omitted.

Even if interstellar travel is impractical, an advanced expansionist civ would be interested in building megastructures. And since there is no stealth in space (unless you can somehow mask heat), they should be observable. Ofc there are explanations for that part of the paradox as well, but the impractical travel theory doesn't cover it.

A hypothetical megastructure Dyson's sphere would not radiate heat. And I'm not so sure that you can apply the stealth principle here. Stealth inhibits active measurement and astronomical measurements are passive. We have sensor resolution and we have a mass of data to sift through - each time sensor generation or data processing advances, we see stuff we haven't seen before. The data is analyzed as a dynamic system.…

> A hypothetical megastructure Dyson's sphere would not radiate heat

Could you elaborate why not? All current technology I know of has an efficiency of <100%, with waste energy being lost as heat (which in space would be radiated away in the infrared spectrum). Why would this not be the case for a hypothetical dyson sphere or swarm?

Re: Grabby Aliens (2021)

#134

Post by jojohohanon »

Why are we now?

https://www.ox.ac.uk/news/science-blog/why-are-we-now

It’s early here, but it think the gist of it is using Bayes to quantify:

Given that the universe would seem to get more hospitable at older ages,

why are we alive now?

IIUC the most likely explanation is some secondary force (aliens) to modify the future hospitality.

Re: Grabby Aliens (2021)

#135

Post by Towaway69 »

api wrote: post #126
yreg wrote: post #118

Earlier quoted context omitted.

How can a particular technology have a non-competitive harmonious society as a hard requirement for it's discovery?

Not a tech per se but I think they’d be more efficient. They’d go for standardization as the default, which would mean far less duplication of effort. They’d only break with that if a gain was to be realized. In many cases higher rank humans block innovation because it threatens them. There’d probably be less if that too. Personally I suspect this is one reason it took 300000 years for humans to start building signif…

I think if we look at pure science (science outside of publish-or-die commercial universities) and see the desire to learn and discover, that is plenty of motivation for many.

Humans have a natural urge to be inquisitive and make their life's simpler. Obviously if war and conflict were to be the only motivational possibilities, then I do wonder how we made it down from the trees!

Re: Grabby Aliens (2021)

#136

Post by scotty79 »

Animats wrote: post #60

Actual article: [1] "We estimate that loud alien civilizations now control 40%–50% of universe volume, each will later control ∼ 10^5 to 3 × 10^7 galaxies, and we could meet them in ∼200 Myr–2 Gyr." Those numbers seem inconsistent. "Ours is a model of grabby aliens, who by definition (a) expand the volumes they control at a common speed, (b) clearly change the look of their volumes (relative to uncontrolled volumes),…

We are living an mining just the skin of our planet. If we achieve technologies to extract interesting resources out of magma w could have boundless resources.

Re: Grabby Aliens (2021)

#137

Post by pfdietz »

willis936 wrote: post #117
pfdietz wrote: post #98

Earlier quoted context omitted.

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.

Sure, but we'd see the markers on timescales relevant to us. The gap between the light cone and actual velocity is the critical difference between a kugelblitz and an invasion: you could conceivably conceal the former but not the latter.

I'm pointing out that any scenario that requires this synchronization is inherently implausible. So if we don't see the markers, trying to say it's because there are lots of civilizations but they just happened to pop up in synchrony with us is not a plausible theory.

Re: Grabby Aliens (2021)

#138

Post by chad_stephens »

ben_w wrote: post #110
distracted_boy wrote: post #87

Earlier quoted context omitted.

We have seen signs, they were called UFOs but are called UAPs now, at least by the US government. People have tried coming forward over the years and talk about the subject, but was met with ridicule. I suggest googling David Grusch to read about the whistleblower from inside US intelligence services. Also search for “Navy Rear Admiral Tim Gallaudet ufo” and you’ll find additional comments. This is the greatest cover…

Such conspiracy theories amuse and confuse me in equal measure. Do you also think North Korea, Cuba, and Iran either don't exist or want to be part of this coverup? Do you live in a world where there's really only one government and any indication to the contrary is mere kayfabe?

I’m sure they do, and for all we know may Iran is part of the conspiracy. Cuba and NK are small fry and are probably excluded.

In the lore, multiple governments are involved in the conspiracy. They keep it secret because it is a race to see who can crack the alien tech the fastest.

There have been cases in the lore of other countries (Brazil and Zimbabwe i believe) having encounters or alleged down aircraft and the US has came in to investigate/recover the down object.

I don’t think there is a world government, but i do think we cooperate with each other.

Also President Clinton says he tried to get information on UFOs but they refused and gave him the runaround.

Re: Grabby Aliens (2021)

#139

Post by cwillu »

zare_st wrote: post #128
yreg wrote: post #115

Earlier quoted context omitted.

Even if interstellar travel is impractical, an advanced expansionist civ would be interested in building megastructures. And since there is no stealth in space (unless you can somehow mask heat), they should be observable. Ofc there are explanations for that part of the paradox as well, but the impractical travel theory doesn't cover it.

A hypothetical megastructure Dyson's sphere would not radiate heat. And I'm not so sure that you can apply the stealth principle here. Stealth inhibits active measurement and astronomical measurements are passive. We have sensor resolution and we have a mass of data to sift through - each time sensor generation or data processing advances, we see stuff we haven't seen before. The data is analyzed as a dynamic system.…

A Dyson's sphere is a device to convert high frequency photons (visible light and uv) to low frequency photons (radiated “heat”). A sufficiently deep stack of shells can bring the temperature of the radiated light closer to the temperature of the cosmic background radiation, but it absolutely will radiate.

Re: Grabby Aliens (2021)

#140

Post by cwillu »

scotty79 wrote: post #122
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.

Lightsail seems sufficiently practical if you don't care about being fast. You basically directly exploit energy of the stars you are traveling between.

The argument is premised on grabby aliens being fast enough to explain why we don't see their expansion; grabby aliens that don't care about being fast would have showed up _long_ ago.
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