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Grabby Aliens (2021)

grabbyaliens.com

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Re: Grabby Aliens (2021)

#51

Earlier quoted context omitted.

Yeah, it's like we're playing cosmic detective trying to figure out if there's anyone else out there in the universe. The fact that we haven't seen any clear signs of alien civilizations doing their thing is kind of mind-boggling. It's like, are they just really subtle about it, or are we just super early to the party?

Or if there is some dark foresting going on or one of a dozen other theories

[deleted]

Re: Grabby Aliens (2021)

#52
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…

Aliens collecting all the light/electromagnetic radiation from stars would be an interesting way to get dark matter. That's one place it could fit. And, if our theories are right, we're at 4.9% regular matter and 26.8% dark matter, so dark matter is five times as much as regular matter, so that's a lot of aliens...

What you're suggesting doesn't make sense.

Dark matter isn't non-luminous matter. It's matter that only interacts gravitationally, but not electromagnetically. This means it doesn't undergo collisions and can't shed angular momentum. It forms a diffuse, largely uniform cloud throughout galaxies. The result is that galaxies are more dense further from the galactic core than we would predict from luminous matter alone.

Re: Grabby Aliens (2021)

#53
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…

Yeah, it's like we're playing cosmic detective trying to figure out if there's anyone else out there in the universe. The fact that we haven't seen any clear signs of alien civilizations doing their thing is kind of mind-boggling. It's like, are they just really subtle about it, or are we just super early to the party?

When you mine asteroids in orbit on a large scale around your star, the released dust/debris would form an IR halo around the star that would be very easy to detect and reveal your presence but we dont see any of it.

So, early humans it propably is.

Re: Grabby Aliens (2021)

#54
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…

It also could be that interstellar travel is possible but never inexpensive enough to be casual or useful for ever-expanding colonization. Or it could be that civilizations stabilize before the point where ever-expanding colonization becomes attractive.

As an example of the latter, look at birth rates in different societies on Earth: Almost universally, they decline to replacement level once they hit a certain level of per-capita wealth.

It’s very likely that a society that achieves interstellar travel will do so after it achieves the ability to provide the highest standard of living for all of its members indefinitely using just the resources of its local system. This already describes Earth; the reasons we don’t do this are ideological, not based on any inherent constraints, while interstellar travel isn’t in our grasp yet and is likely to be extraordinarily costly.

Such a society wouldn’t face any pressure to grow, so any colonization would itself likely be ideological—“We don’t want to do things Surak’s way, let’s pull up stakes and find a world where we can live the way we want!”—or as a contingency/hedge against large-scale existential risk. Neither demand colonizing even a small fraction of a galaxy, assuming habitable worlds are even remotely plentiful near and reachable from the origin world.

Re: Grabby Aliens (2021)

#55
post #26
post #7

Earlier quoted context omitted.

> implication that humans are possibly one of the earliest sentient spacefaring species to have appeared so far. Or that perhaps we're a simulation. We exist in a very interesting time in history when the pieces are coming together. Our hypothetical future robot descendents may be very interested in learning about their past.

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 made it impossible for them to fully prevent it, only dissuade us from looking into it.

This is kind of why I mostly find the discussion of whether we're in simulation to pretty quickly reach a point where it stops being interesting even from a philosophical perspective. I don't really see how you can differentiate between fundamental properties that we observe that reflect the "real" universe where we're just a simulation and fundamental properties that explicitly designed for the purpose of the simulation itself and may not actually reflect the "real" universe. We might as well ask if the OS our simulation is running on has a toggle for dark mode or not.

Re: Grabby Aliens (2021)

#56
post #52

Earlier quoted context omitted.

Aliens collecting all the light/electromagnetic radiation from stars would be an interesting way to get dark matter. That's one place it could fit. And, if our theories are right, we're at 4.9% regular matter and 26.8% dark matter, so dark matter is five times as much as regular matter, so that's a lot of aliens...

What you're suggesting doesn't make sense. Dark matter isn't non-luminous matter. It's matter that only interacts gravitationally, but not electromagnetically. This means it doesn't undergo collisions and can't shed angular momentum. It forms a diffuse, largely uniform cloud throughout galaxies. The result is that galaxies are more dense further from the galactic core than we would predict from luminous matter alone.

I'm speaking outside my area, but dark matter is not really confirmed to even exist?

Re: Grabby Aliens (2021)

#57
post #49

My go-to counterargument for this is that galaxies are really far apart (from us to Andromeda is 25x the diameter of the Milky Way). If you haven't developed FTL travel, it's a long haul with very little benefit on the way.

Your "counterargument" is a presumption in Fermi paradox models. The alternative isn't particular interesting.

Re: Grabby Aliens (2021)

#58
post #52

Earlier quoted context omitted.

What you're suggesting doesn't make sense. Dark matter isn't non-luminous matter. It's matter that only interacts gravitationally, but not electromagnetically. This means it doesn't undergo collisions and can't shed angular momentum. It forms a diffuse, largely uniform cloud throughout galaxies. The result is that galaxies are more dense further from the galactic core than we would predict from luminous matter alone.

I'm speaking outside my area, but dark matter is not really confirmed to even exist?

It's consistent with observational evidence. You are correct that no one has detected dark matter particles.

Re: Grabby Aliens (2021)

#59
post #52

Earlier quoted context omitted.

What you're suggesting doesn't make sense. Dark matter isn't non-luminous matter. It's matter that only interacts gravitationally, but not electromagnetically. This means it doesn't undergo collisions and can't shed angular momentum. It forms a diffuse, largely uniform cloud throughout galaxies. The result is that galaxies are more dense further from the galactic core than we would predict from luminous matter alone.

I'm speaking outside my area, but dark matter is not really confirmed to even exist?

https://youtu.be/nbE8B7zggUg?si=QcBpuxSvXsGGxTKk

Re: Grabby Aliens (2021)

#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), (c) are born according to a power law in time except not within other GC volumes, and (d) do not die unless displaced by other GCs."

That's an interesting set of assumptions. Kind of a 1960s science fiction model.

If we now have a reasonable understanding of physics, you get a different model. No FTL, radio works at light speed,

Technological civilizations may not last all that long. Human civilization is about 6,000 years old. Heavy industrial civilization is about 200 years old. Most mineral resources already are past the point where the easy stuff has been mined. The USGS tracks total worldwide mineral resources.[2] On a scale of years, things look good. On a scale of centuries, not good. On a scale of millennia...

[1] https://iopscience.iop.org/article/10.3847/1538-4357/ac2369/...

[2] https://www.usgs.gov/publications/mineral-commodity-summarie...

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