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Grabby Aliens (2021)

grabbyaliens.com

191–200 of 227 posts

Re: Grabby Aliens (2021)

#191
post #186

Earlier quoted context omitted.

Of course it makes no sense if you are answering the wrong question. The question being asked is not: "Why do we not see grabby aliens?" The question being asked is: "Under what circumstances can humanity become grabby aliens that colonize the galaxy in reasonable time given that we do not see grabby aliens?" The simplest circumstances that would allow humanity to become grabby aliens in the future is that becoming g…

> if there is a hope that humanity will become grabby aliens (Star Trek). You talk as if being a loud grabby alien to other space civilizations is a hopeful thing for humanity to aspire to. Did not Star Trek had a Prime Directive for some reason? Though I do like solving the Fermi Paradox by humanity taking a good hard look in the mirror. May disprove us being Big Foot Medusas with one stone too. Humanity just got ri…

You are arguing a meaningless point. The argument form takes what you hope humanity will become as a parameter. You extrapolate from there to determine under what circumstances humanity can become that desired future given the facts we have available.

If we assume that every intelligent species will turn the universe into goo within 10,000 years of achieving human-level technology, then that is only compatible with the fact that the universe is not currently goo under very limited circumstances. Again, I am not arguing that is the future or desirable, I am merely stating that if you believed that then you must also believe that we are also in one of those very limited set of circumstances. Otherwise you need to rethink your beliefs.

The analysis made in the article is: "Assume you want humanity to expand to the stars and that humanity is not special or unique in temperament so aliens will do so as well. Humanity can only come into existence under a limited set of parameters and there are only a limited set of parameters that explain the data we have available."

Re: Grabby Aliens (2021)

#192
post #94

Earlier quoted context omitted.

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)

But we are not "so early" in the history of the universe. Something like 95% of all the stars that will ever be formed have already been formed. It's actually rather late in the day.

> Something like 95% of all the stars that will ever be formed have already been formed.

Sure, but clearly civilizations don't exclusively develop around newly formed stars: we didn't. Most stars are red dwarves and will continue shining for trillions of years.

Re: Grabby Aliens (2021)

#193

Earlier quoted context omitted.

Which is exactly my point. The question isn't whether Dyson speheres radiate, the question is can we detect an artificial megastructure and my answer is no, based on the hypothetical Dyson design.

That is physically impossible unless there is new physics in that hypothetical design. All physical objects radiate heat and a Dyson sphere in particular would be trivial to detect. You look take a picture of the sky in infrared and in the visible spectrum. If you find an infrared source but no associated visible star you’ve got a strong candidate for being a Dyson sphere. Such searches have actually been conducted.…

> If you find an infrared source but no associated visible star you’ve got a strong candidate for being a Dyson sphere

You mean like brown dwarfs?

Re: Grabby Aliens (2021)

#194
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…

> 4. Something that we have already noticed is actually evidence of grabby aliens, but it is happening in every direction so we assume that it is a natural phenomenon, because it is so uniform

* Brown dwarfs: These are objects with masses too small to ignite nuclear fusion in their cores and shine like stars. However, they are still warm enough to emit infrared radiation.

* There are rogue planet candidates that do not belong to a solar system.

Re: Grabby Aliens (2021)

#195

Earlier quoted context omitted.

No, I imagine them doing exactly the same thing we are: using more and more efficient methods of communication as we develop them. Compressing and encoding data, focusing our transmissions where they need to be instead of blasting at max power in all directions, using the most effective form of transmission for the purpose whether it’s laser, microwaves, specific wavelengths of radio, or hard line connections for pla…

[flagged]

You should really look into the limits of radio astronomy, it’s not as easy as you seem to think.

Re: Grabby Aliens (2021)

#196
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…

5. Grabby aliens do not exist because the universe is a dark forest and any detectable signs of life result in anonymous relativistic snowflake bombardment.

Re: Grabby Aliens (2021)

#197
post #110

Earlier quoted context omitted.

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 U…

My previous (brief) line manager was Iranian. I asked him if the Iranian rhetoric about the USA being "the great Satan" was a translation issue or sincere, he said it was sincere.

Re: Grabby Aliens (2021)

#198

Earlier quoted context omitted.

If you assume FTL travel will never be developed then distance and time are simple limiting factors. How do you keep a cohesive civilization going when communication takes 200 years? Or even just 20? Here on Earth entirely new languages and cultures arose across distances that wouldn’t even cross a state line when communication was limited to a small handful of travellers and merchants. Any colony further away than 5…

Consider a colony of bacteria multiplying by splitting. Each new pair of cells is independent and do not cooperate. Some die, some stay put. Nonetheless, the “colony” spreads and explores new territory with zero coordination of these activities. Certainly not an intelligent centralised leadership! Even if our first interstellar colonies diverge immediately and some even turn into reclusive hermits, some may expand, r…

Hard to say what would happen but I think we still need to avoid the assumption that each star system remains relatively static especially over very long periods of time. You also need to consider the purpose behind colonization, if it is to spread the existence of your civilization to new worlds then no one says those worlds must be uninhabited.

Re: Grabby Aliens (2021)

#199
post #55
post #26

Earlier quoted context omitted.

We wouldn't know if we're in a simulation unless the diety/programmer wanted us to know that.

How would you know? Based on what we know of simulations in this reality, which has rules designed by whoever created it? If you're programming a simulated universe and don't want its inhabitants to know, it seems like a pretty obvious mechanism to try to enforce that would be to make the rules so that it seemed like "leaking" information into a simulation was impossible, even if the rules of their "outer" reality ma…

> How would you know?

Belief is simulated knowledge and we exist within our believed world...so we are in a simulation of some kind, but we don't know if we are also in "the" kind.

Re: Grabby Aliens (2021)

#200
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.…

Rough calculation get's me a dyson sphere big enough to bring the black body radiation of the sun down to ~4k being hundreds of times the orbit of pluto. At that point it's actually an interesting question of where you get all the mass for the nesting shells.

R_sol^2T_sun^4 = R_shell^2T_cmb^4 (R_sol^2*(T_sun/T_cmb)^4)^(1/2) ~= 2 light months.

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