Have we already been visited by aliens? • Hacker News Board

Re: Have we already been visited by aliens?

#351

Post by munificent » Thu, Jan 21, 2021, 5:17 PM UTC

kls wrote: post #239

munificent wrote: post #236

Earlier quoted context omitted.

> Ridiculing scientists for plausible hypothesis seems very unscientific. Your statement is self-referential. If a hypothesis is "plausible" than practically by definition it is above ridicule. But how do you decide which hypotheses are plausible? Science, at its core, is a social system. One of the key goals of that system is prioritization. There are finite research resources and it's important to allocate them to…

Ridicule is one of the more extreme tools scientists use in that social process to reach consensus about which hypotheses are plausible. It is also a very sinister and discrediting tool. As an example the CRU employed this tactic and set an entire area of scientific research back due to the optics of scientific politics. It can cause the tainted smell of agenda, and that is never good for enlightening people.

> It is also a very sinister and discrediting tool.

Agreed, but self-aggrandizement, manipulation, and outright fraud are also tools in the toolbox and if you don't have strong enough defensive tools, you are open to attacks from those. Obviously, they can be misapplied. Humans are not perfect. But without powerful social tools like ridicule and shunning, science becomes essentially a honeypot for charlatans like Andrew Wakefield.

Re: Have we already been visited by aliens?

#352

Post by openasocket » Thu, Jan 21, 2021, 5:48 PM UTC

sterlind wrote: post #114

GoblinSlayer wrote: post #102

Earlier quoted context omitted.

Already done for indians. Impossibility of FTL travel just saved all life in universe from you.

What wiped out most of the Indians was plague and genocide while seizing territory and resources. I don't think plague would be an issue - viruses require proteins to be similar to attach and reproduce, and bacteria require nutrients to be the same. And as for resources? Asteroid mining will get you more water, minerals and metals. But territory - terraforming might be really difficult or take too long. If aliens nee…

I actually think a planet with life already on it may be the worst candidate for territory. Sure, there's unlikely to be a plague that can affect them, but there are millions of proteins and organic compounds on our planet that alien life has never been exposed to before. The odds are high that some substance that is commonplace on our planet has a toxic interaction with the aliens. Even if the aliens have a similar biology to our own (carbon based life with DNA, same cell structure and organelles, etc.) if they use a different chirality of an amino acid you could have tons of potential for toxic interactions. If that is the case, the only way to make the planet habitable is to wipe out all life on the planet, AND break down all of the toxic proteins, at which you're basically doing terraforming anyway.

But yeah I agree that there's very little our planet has that an alien civilization would want. The only reasons I could see for war would be some sort of pre-emptive response ("some day they will be able to attack us, let's wipe them out before they can") or an ideological conflict. Maybe they have a religion/ideology/culture that sees us as needing to be destroyed. Maybe if they see us as a lesser race to be exterminated, like the Nazis. Or maybe we are evil in their morality. There's the sci-fi staple of seeing mankind as inherently violent and warlike, or polluting, but also more exotic things. Maybe they are immortal and don't reproduce, and see us and our potential for expansion as a sort of cosmic cancer. Maybe they are photosyntheic beings, and see anything that lives by consuming other life as a threat. But I think those are unlikely.

At the very least I think that they wouldn't wipe us out on sight. If they did have strong opinions on religion or forms of government, it would likely take years of contact and dialogue to even figure out we were in disagreement. Even then diplomacy and diplomatic pressure would probably be used long before military force.

Re: Have we already been visited by aliens?

#353

Post by yters » Thu, Jan 21, 2021, 6:14 PM UTC

sailingparrot wrote: post #335

yters wrote: post #294

Earlier quoted context omitted.

What is the evidence? Seems hard to have evidence for anything billions of years ago given we don't have historical records past a few millenia. It is all guesswork past that point, and the patterns of organisms and their complexity makes an earth origin of DNA extremely improbable if not impossible. Try reading through a graduate level book on bioinformatics to marvel at the sheer ingenuity, for lack of a better wor…

You can look up origin of DNA there is a ton of good resource, but one of the main reason is that we know all life on earth does not use the same DNA, some domain uses DNA based on a certain set of protein while some other domain uses DNA based on another set, which is very strong evidence that DNA was 'invented' multiple times. So if the building blocks of life arrived from somewhere else, it was at best RNA not DNA…

No idea where it came from, but if someone found a computer in the middle of the desert and said it evolved over millions of years, I would be doubtful. DNA is many orders of magnitude more finely adapted and complex than computers, and to boot does much more with 6GB than our best coders. It is just inconceivable that random mutation and natural selection can do this. Just try your hand at a genetic algorithm to see just how incapable they are.

Anyways, just because we don't have a good explanation is no reason to substitute an obviously false explanation. That would be just as bad as creationists saying God did it, since both shut down looking for better ideas.

Re: Have we already been visited by aliens?

#354

Post by sailingparrot » Thu, Jan 21, 2021, 6:26 PM UTC

yters wrote: post #353

sailingparrot wrote: post #335

Earlier quoted context omitted.

You can look up origin of DNA there is a ton of good resource, but one of the main reason is that we know all life on earth does not use the same DNA, some domain uses DNA based on a certain set of protein while some other domain uses DNA based on another set, which is very strong evidence that DNA was 'invented' multiple times. So if the building blocks of life arrived from somewhere else, it was at best RNA not DNA…

No idea where it came from, but if someone found a computer in the middle of the desert and said it evolved over millions of years, I would be doubtful. DNA is many orders of magnitude more finely adapted and complex than computers, and to boot does much more with 6GB than our best coders. It is just inconceivable that random mutation and natural selection can do this. Just try your hand at a genetic algorithm to see…

> No idea where it came from

Yes that's why I am suggesting you go read some research about it from people that know a thing or two about the subject.

Just because you personally, with an outsider perspective and no specific knowledge about this field, have a tough time believing DNA could have evolved here does not make it so.

The state of our understanding stops at RNA not at DNA. So if something came from somewhere else, once again, it was RNA. You don't get to draw the boundaries of what we know and don't just based on your gut feeling and cheap analogies.

Re: Have we already been visited by aliens?

#355

Post by yters » Thu, Jan 21, 2021, 7:50 PM UTC

sailingparrot wrote: post #354

yters wrote: post #353

Earlier quoted context omitted.

No idea where it came from, but if someone found a computer in the middle of the desert and said it evolved over millions of years, I would be doubtful. DNA is many orders of magnitude more finely adapted and complex than computers, and to boot does much more with 6GB than our best coders. It is just inconceivable that random mutation and natural selection can do this. Just try your hand at a genetic algorithm to see…

> No idea where it came from Yes that's why I am suggesting you go read some research about it from people that know a thing or two about the subject. Just because you personally, with an outsider perspective and no specific knowledge about this field, have a tough time believing DNA could have evolved here does not make it so. The state of our understanding stops at RNA not at DNA. So if something came from somewher…

I have researched the topic extensively, and no one has any idea. It is all just speculation that fails when you try reducing the ideas to practice.

Can you recommend what you consider hard evidence?

Re: Have we already been visited by aliens?

#356

Post by vladTheInhaler » Thu, Jan 21, 2021, 8:16 PM UTC

naikrovek wrote: post #350

vladTheInhaler wrote: post #313

Earlier quoted context omitted.

> I can't give details because they don't exist. Right. And if the argument depends on those details, then it's not a very convincing argument.

My argument is that pollution outlives a society that it kills by a non-zero amount of time.

I understand. And my argument is that nonzero isn't a good enough lower bound to justify investing in something like that. Oxygen is produced by even very simple organisms, and thus has been present in our atmosphere in significant concentrations for billions of years, currently makes up 20+ percent, and its residence time is 4,500 years [1]. On the other hand, many CFC concentrations are measured in parts per trillion, and have a residence time measured in years or decades [2], and have only existed at all for a century or so at most. Even if every single living thing on this earth died tomorrow, oxygen would be detectible long, long after many pollutants were gone. And chances are, if anything were to survive the kind of disaster that would wipe out humanity, it would be something like the single-celled organisms that excrete oxygen. I'm prepared to believe that you're correct, but you have to present some more compelling evidence.

[1] https://en.wikipedia.org/wiki/Oxygen_cycle#Capacities_and_fl...

[2] https://cdiac.ess-dive.lbl.gov/pns/current_ghg.html

Re: Have we already been visited by aliens?

#357

Post by wait_a_minute » Thu, Jan 21, 2021, 8:20 PM UTC

GoblinSlayer wrote: post #337

wait_a_minute wrote: post #190

Earlier quoted context omitted.

The trend of our species has been to become more moral and nice to one another. Read up on how humans viewed one another 1,000 years ago or 10,000 years ago and see the trend. There's no reason to believe or to ONLY believe that we'd be a violent and evil species if we became space-fairing and had FTL travel. In such a far future, I'd like to choose to work towards and to think about having a society that is even mor…

That's ok, in 10000 years when we will think better, we can fly to the stars.

Or even in 10 years.

Re: Have we already been visited by aliens?

#358

Post by PaulDavisThe1st » Thu, Jan 21, 2021, 9:11 PM UTC

godelski wrote: post #265

PaulDavisThe1st wrote: post #237

Earlier quoted context omitted.

I think this is a mistaken way of thinking in general, because you're omitting time. Your assuming that intelligent/thinking/conscious creatures would necessarily function on timelines that make sense to us. If that were true, then what you're saying makes sense - there are real bounds on how fast you can move chemical energy from A to B, for example. But I see nothing preventing intelligent life from operating on ma…

I think this is strange thinking because it breaks our laws of physics. The clock ticks at the same rate in internal reference frames, it is only different when looking at two different frames. But if you're talking about them acting at slower speeds or faster, then that brings along other problems similar to the mechanics ones we discussed (assuming we're not counting that they are in a slower reference frame). It r…

Good points, but ...

consider the range of timescales that humans can have effective control over. We manage to organize subatomic collisions that occur in femto-seconds, and we manage to build things that last thousands of years. All this despite the fact that our own lives are measured in units that are several orders of magnitude smaller or larger.

So I can imagine (just about) an intelligent system that can also effectively build systems operating in time domains orders of magnitude from their own experience/lifetimes. If they were very "slow" then certainly launching objects into orbit may appear almost impossibly fast to them. But it wouldn't be notably different than what we do with particle physics (or even firing a gun), where the timescale of the event is essentially impercetible to us, and far beyond our ability to control with our own bodies.

The other way around is harder, because creating things that last much longer than an individual's lifetime has to fall back on culture, and that seems to evolve (change) much more rapidly. There are very few buildings still in use that are more than a thousand years old, even though the physical construction of such a thing is relatively trivial.

Re: Have we already been visited by aliens?

#359

Post by GoblinSlayer » Thu, Jan 21, 2021, 9:38 PM UTC

openasocket wrote: post #341

GoblinSlayer wrote: post #317

Earlier quoted context omitted.

To construct R you need to repeat Dedekind cut uncountable number of times, i.e. you need to iterate over all real numbers, which would make them countable.

You don't need any sort of "repetition" of Dedekind cuts to construct the real numbers, it's actually fairly straightforward. The set of all Dedekind cuts is a subset of the power set of rational numbers (i.e. each Dedekind cut is a set of rational numbers) satisfying the following properties: for each Dedekind cut A 1. A is not the empty set 2. A is not the set of all rational numbers 3. A is closed downwards, meani…

So you just assume that the set exists.

Re: Have we already been visited by aliens?

#360

Post by pdimitar » Thu, Jan 21, 2021, 10:27 PM UTC

emmelaich wrote: post #244

eloff wrote: post #215

Earlier quoted context omitted.

There is a balance here, you are correct, but I think we currently skew too far toward gatekeeping. Too little gatekeeping means trouble finding the signal through the noise and time wasted on dead ends. Too much and good ideas get neglected or squashed for far too long. There is a cost to both.

There's another aspect - with strong gatekeeping it is assumed that those theories that make it through are true.

Not really, they often are simply in tune and in agreement with the currently established group-think.