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Grabby Aliens (2021)

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Re: Grabby Aliens (2021)

#151

Post by throwuwu »

tsimionescu wrote: post #76
bqmjjx0kac wrote: post #56

Earlier quoted context omitted.

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

It's clearly confirmed that galaxies don't obey the known laws of quantum electrodynamics (QED) + general relativity (GR) if we assume they are made entirely of Standard Model particles. So, either QED is wrong (extremely unlikely) or GR is wrong (unlikely) or there is some matter that is not in the Standard Model (plausible). Dark matter corresponds to option 3 - and there are observations that conform some models o…

What if they’re really greedy about energy and store everything they can in superconductors?

Re: Grabby Aliens (2021)

#152

Post by throwuwu »

iraqmtpizza wrote: post #145
LadyCailin wrote: post #103

Earlier quoted context omitted.

That’s like looking only in the drawer, and saying, there is no evidence here that a cat lives in this house. When in fact the cat is just upstairs.

There are electromagnetic waves reaching the earth from this galaxy which were emitted anywhere from 80,000 years ago to an instant ago, and everywhen in between. Practically all alien races among the hundreds of billions of solar systems would have to have been electromagnetically silent for a minimum of 80 thousand years for us not to see them. If you include other galaxies, then they would've had to have been sile…

Not silent, just not broadcasting.

Re: Grabby Aliens (2021)

#153

Post by [deleted] »

Towaway69 wrote: post #135
api wrote: post #126

Earlier quoted context omitted.

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!

[deleted]

Re: Grabby Aliens (2021)

#154

Post by tsimionescu »

throwuwu wrote: post #151
tsimionescu wrote: post #76

Earlier quoted context omitted.

It's clearly confirmed that galaxies don't obey the known laws of quantum electrodynamics (QED) + general relativity (GR) if we assume they are made entirely of Standard Model particles. So, either QED is wrong (extremely unlikely) or GR is wrong (unlikely) or there is some matter that is not in the Standard Model (plausible). Dark matter corresponds to option 3 - and there are observations that conform some models o…

What if they’re really greedy about energy and store everything they can in superconductors?

Superconductors still have an EM signature, they still have magnetic fields around them and are detectable.

Re: Grabby Aliens (2021)

#155

Post by tsimionescu »

ben_w wrote: post #104
tsimionescu wrote: post #76

Earlier quoted context omitted.

It's clearly confirmed that galaxies don't obey the known laws of quantum electrodynamics (QED) + general relativity (GR) if we assume they are made entirely of Standard Model particles. So, either QED is wrong (extremely unlikely) or GR is wrong (unlikely) or there is some matter that is not in the Standard Model (plausible). Dark matter corresponds to option 3 - and there are observations that conform some models o…

> So, either QED is wrong (extremely unlikely) or GR is wrong (unlikely) Not my area, but I thought both were known to be incomplete? Q because it presumes a flat spacetime; R because it predicts the formation of singularities that the maths used to develop it assume don't exist?

I think the general belief is that it will turn out that space time is actually approximately flat at small levels, so that QED will be essentially exactly correct, while GR will turn out not to apply past a certain small scale.

Re: Grabby Aliens (2021)

#156

Post by cwillu »

FrustratedMonky wrote: post #143
cwillu wrote: post #141

Earlier quoted context omitted.

The universe isn't a rock concert, “we're here too early” is not the only possible reason why there's no band on the stage.

? Did you read the original post? On grabby aliens? This whole discussion is about being 'early'. Not sure you are making a point. Edit: The original post discusses below light speed transportation. 25% speed of light is used in the estimates. But guess I agree, if no aliens including us, never-ever with infinite time ever develop transportation that can get up to some fraction of light speed. Then maybe no colonizat…

“Alas, there's a fifth possibility” was my comment, and I made it because the discussion was excluding the possibility, despite it being explicitly discussed in the paper.

“We can't see any evidence because there is nothing there to see” is a possibility, grabby aliens _requires_ significant-fraction-of-C travel for the argument to hold, and it's entirely possible that it's just impractical-to-the-point-of-impossibility. (That's why I quoted it in another comment).

Yes, it's possible that we're early. It's equally possible that we're “early” because there's no concert: _everybody_ is early in a universe where the band never gets on stage and it turns out that nobody bothers colonizing the universe due to the cost and lack of benefits.

See also: “Please don't comment on whether someone read an article. "Did you even read the article? It mentions that" can be shortened to "The article mentions that".” https://news.ycombinator.com/newsguidelines.html

Re: Grabby Aliens (2021)

#157

Post by iraqmtpizza »

throwuwu wrote: post #152
iraqmtpizza wrote: post #145

Earlier quoted context omitted.

There are electromagnetic waves reaching the earth from this galaxy which were emitted anywhere from 80,000 years ago to an instant ago, and everywhen in between. Practically all alien races among the hundreds of billions of solar systems would have to have been electromagnetically silent for a minimum of 80 thousand years for us not to see them. If you include other galaxies, then they would've had to have been sile…

Not silent, just not broadcasting.

[flagged]

Re: Grabby Aliens (2021)

#158

Post by FrustratedMonky »

cwillu wrote: post #156
FrustratedMonky wrote: post #143

Earlier quoted context omitted.

? Did you read the original post? On grabby aliens? This whole discussion is about being 'early'. Not sure you are making a point. Edit: The original post discusses below light speed transportation. 25% speed of light is used in the estimates. But guess I agree, if no aliens including us, never-ever with infinite time ever develop transportation that can get up to some fraction of light speed. Then maybe no colonizat…

“Alas, there's a fifth possibility” was my comment, and I made it because the discussion was excluding the possibility, despite it being explicitly discussed in the paper. “We can't see any evidence because there is nothing there to see” is a possibility, grabby aliens _requires_ significant-fraction-of-C travel for the argument to hold, and it's entirely possible that it's just impractical-to-the-point-of-impossibil…

No. Your point is not clear at all.

And I can ask for clarification concerning if you read the original post, since your objection/point was already covered.

Did you read it and simply making some additional argument against it, or did you miss it entirely?

"5. Controlled transportation between the stars, sufficient for colonization, is sufficiently impractical that there are no grabby aliens within our light-cone. "

This is covered in the other points of the theory? So should I assume you read it?

"The universe isn't a rock concert, “we're here too early” is not the only possible reason why there's no band on the stage. "

"Don't be snarky. " https://news.ycombinator.com/newsguidelines.html

Re: Grabby Aliens (2021)

#159

Post by BugsJustFindMe »

bonzaidrinkingb wrote: post #129

This theory is itself grabby, and grabs itself at that. > Furthermore, we should believe that loud aliens exist, as that’s our most robust explanation for why humans have appeared so early in the history of the universe. But if loud aliens will soon fill the universe, and prevent new advanced life from appearing, that early deadline explains human earliness. Even furthermore, we should believe that Big Foot Medusas e…

Yeah, the first reaction to "we should believe that loud aliens exist, as that’s our most robust explanation for why humans have appeared so early" should be "sorry, but that's not how explanation, loudness, or existing work."

The most robust explanation for why we're here now is that unlikely things happen all the time, and we only think that's weird because of anthropic bias.

Re: Grabby Aliens (2021)

#160

Post by api »

cwillu wrote: post #67
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…

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.

There are many middle possibilities between that and aliens expanding at c.

Expansion at c is very unlikely. Insane things happen when you approach c, like the cosmic microwave background transforming into a gamma ray laser aimed at your head and collisions with microscopic particles destroying you. It may be that travel close to c is so hard as to be effectively impossible.

I’ve read that speeds up to about 30% the speed of light are “thinkable” with currently known physics plus advances like compact fusion reactors. Think something that looks like the Epstein Drive in The Expanse or the ships from Avatar.

These models provide indirect evidence against the existence of FTL travel. If FTL exists it means we really have to be extremely early, maybe even the first in our galactic cluster. Otherwise someone would have visited at least.

I also think if someone has visited, such as if some tiny number of UFOs are actually of ET origin, it means we are probably incredibly lucky to have neighbors that aren’t “reapers” in the dark forest sense. It’d be funny if our galaxy is actually full of aliens and we lucked out and are camped next to some superintelligence that is both benevolent and powerful enough to fight off anyone who isn’t. So hey if they’re taking our cattle maybe that’s a pretty small price to pay.

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