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

Re: Have we already been visited by aliens?

#241

Post by 7thaccount » Thu, Jan 21, 2021, 1:04 AM UTC

y-c-o-m-b wrote: post #103

AnIdiotOnTheNet wrote: post #35

> Loeb, though, explicitly rejects the Sagan standard—“It is not obvious to me why extraordinary claims require extraordinary evidence,” he observes—and flips its logic on its head: “Extraordinary conservatism keeps us extraordinarily ignorant.” So long as there’s a chance that 1I/2017 U1 is an alien probe, we’d be fools not to pursue the idea. “If we acknowledge that ‘Oumuamua is plausibly of extraterrestrial-techno…

> If we assume that Oumuamua is an alien construct, what "new vistas of exploration for evidence and discovery" open up that we are not already pursuing? I think what he's trying to convey is that thinking of this object under the assumption of "aliens" pushes us to develop experimental technology to prove it. This could then lead to future advances (whether intentional or accidental) potentially helping us detect al…

We don't need Oumuamua to push technology further and further. We're already pushing. Now if some aliens showed up on a star cruiser and told us Warp drive is easily obtainable without massive amounts of energy. Then, that would be a new goal to direct ourselves to that could inspire us.

Re: Have we already been visited by aliens?

#242

Post by userulluipeste » Thu, Jan 21, 2021, 1:07 AM UTC

6gvONxR4sf7o wrote: post #142

ncmncm wrote: post #112

Earlier quoted context omitted.

Their best future course is to stop sniping at one another. It is possible that it's aliens. It is possible that it's not. We don't have enough evidence even to estimate probabilities, so anything further is pure speculation. Speculation is a look that wears no better on conservatives than on radicals. There is hardly a field to be found where young radicals are not promoting evidence for what the tenured consider an…

> Loeb is right about one thing: the notion of "extraordinary evidence" is very destructive. Evidence is evidence. I agree with pretty much everything you're saying except this. Though I still do agree with this a bit. It seems like a shorthand for "be bayesian" that's unfortunately taken too far too frequently. But if I have a strong prior one way or another, I will need stronger evidence to turn me around. +1 on yo…

There are things (think of Higgs boson type) that lie on the limit of observability/detection, for which there isn't any guarantee that there will ever be means strong enough to qualify for the same level of rigorous study as most of the scientists are comfortable with. The easiest thing to do is to draw a line and to dismiss everything that goes beyond it. The smarter thing to do (in my view) is to recognize the decrease of control and accuracy in our means and classify the fields of study accordingly, then both asking and granting different levels of trust to what is being studied.

Re: Have we already been visited by aliens?

#243

Post by px43 » Thu, Jan 21, 2021, 1:10 AM UTC

So what are the odds of us being able to fire something off to catch up with this thing? I feel like I haven't seen this discussed, but presumably if it's no longer accelerating, it should be relatively easy to locate right?

We should at the very least start building out the capability to fire off something at the next mystery rock that floats by.

Re: Have we already been visited by aliens?

#244

Post by emmelaich » Thu, Jan 21, 2021, 1:11 AM UTC

eloff wrote: post #215

ntsplnkv2 wrote: post #181

Earlier quoted context omitted.

This is a good thing. If we entertained every crackpot theory we would waste tons of time. it's good for there to be some gatekeeping. Of course sometimes they're wrong - but so what? That will come out if there is actual evidence.

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.

Re: Have we already been visited by aliens?

#245

Post by yters » Thu, Jan 21, 2021, 1:12 AM UTC

sailingparrot wrote: post #208

yters wrote: post #172

If not, where did our dna come from?

If yes, where does their dna (or the equivalent of it) comes from? You are just kicking the can a bit further.

Somewhere else! Dna is too marvelous for evolution, it cannot have originated here!

Re: Have we already been visited by aliens?

#246

Post by Retric » Thu, Jan 21, 2021, 1:14 AM UTC

BobbyJo wrote: post #212

Retric wrote: post #118

Earlier quoted context omitted.

I chose unusual as it had thrust consistent with comets. After ruling out solar-radiation pressure, drag- and friction-like forces, interaction with solar wind for a highly magnetized object, and geometric effects originating from 'Oumuamua potentially being composed of several spatially separated bodies or having a pronounced offset between its photocentre and centre of mass, we find comet-like outgassing to be a ph…

If you listen to his podcast with Lex he explains that the outgassing needed to give it the acceleration it had would require 10% of it's mass to cook off, as well as all of it had to be hydrogen else we'd have seen the trail. Why consider a comet made entirely of hydrogen more likely than an alien probe?

The paper addresses that point.

The model predictions for the magnitude and temporal evolution of the non-gravitational acceleration are within a factor of about 2–3 of the observations (see Methods) for a water production rate of QH2O = 4.9 × 1025 molecules s−1 (or 1.5 kg s−1) near 1.4 au and an addi- tional contribution from QCO = 4.5 × 1025 molecules s−1 (or 2.1 kg s−1). Outgassing at this level does not conflict with the absence of spectro- scopic detections for outgassing of OH, because the values quoted are well below the spectroscopic limits on production rates16. However, the inferred upper limits for water production at 1.4 au, which are based on the non-detection of CN7 and assumed Solar System abundances for QCN/QOH17, show that ‘Oumuamua would need to be substantially depleted in CN (by a factor of more than about 15) relative to water.

And:

However, if the grains are predominantly larger than a few hundred micrometres to millimetres, they would not have been detected at optical wavelengths (see Methods). In the Solar System, comet 2P/Encke is noteworthy for its lack of small dust near perihelion18. Cometary behaviour implies that ‘Oumuamua must have some internal strength, at least comparable to Solar System comets19, because asteroid-like densities are ruled out (see Methods).

It’s an interesting read, suggesting interstellar space as being significantly different than what you see inside solar systems.

Re: Have we already been visited by aliens?

#247

Post by emmelaich » Thu, Jan 21, 2021, 1:15 AM UTC

galkk wrote: post #151

yoz-y wrote: post #120

Earlier quoted context omitted.

The books and all are nice but the Dark Forest Theory doesn't hold agains much scrutiny. Among other reasons because if that were true we would be already dead. https://www.youtube.com/watch?v=zmCTmgavkrQ

I mean - it's called Dark Forest, but if you will look at any documentary, even dark forest is full of life. You will hear crickets, you will hear owls, you may see fireflies. The theory has catchy name, but even the earth's nature disproves it.

The analogy is flawed, doesn't mean it's not useful.

Applied to a forest on earth, you'd have to make the animals are extremely slow.

Re: Have we already been visited by aliens?

#248

Post by willis936 » Thu, Jan 21, 2021, 1:19 AM UTC

PaulDavisThe1st wrote: post #235

stretchcat wrote: post #180

Earlier quoted context omitted.

Every advancing civilization will eventually create an internet. Once they do that, interstellar travel is off the table. Advanced civilizations stay closely packed because they cannot tolerate latency once they get a taste for near instant communication.

Given that serious interstellar travel really requires FTL transport, I suspect that the two are rather closely connected.

Why is FTL necessary for interstellar travel? If you could go even 1% c then you could make journies that are multiple light years on the scale of centuries. It’s not until 50% c does time dilation start playing a significant role, but it would allow making a 10 l-yr journey in 17 years.

Nature doesn’t care if we think there should be aliens or FTL travel. Nature doesn’t like casualty violated and that means we’re all going to be following its rules on the speed of causality. There are no cosmic-scale sentient forces that can shape space-time near us or else we would have noticed in observations decades ago.

Re: Have we already been visited by aliens?

#249

Post by wait_a_minute » Thu, Jan 21, 2021, 1:25 AM UTC

7thaccount wrote: post #166

cpuguy83 wrote: post #43

Earlier quoted context omitted.

The ideals behind the Prime Directive were from Vulcan influence. The theory behind it is they tried to do exactly that and it led to disaster in every case.

A lot of scifi shows have been influenced by this. In Stargate SG-1 (spoilers): The Tollan civilization were humans taken from earth millennia ago that developed science faster than us and ended up being one of the most advanced races in the galaxy. They gave a source of limitless energy to more primitive aliens on a nearby planet in their solar system (think Mars versus Earth) and those aliens weaponized it and blew…

I'm just really skeptical that an advanced species like that couldn't figure out the appropriate way to save another species from destruction/stagnation without collapsing everything. Just feels like an immensely negative perspective when we could easily just choose a more positive one.

Re: Have we already been visited by aliens?

#250

Post by kls » Thu, Jan 21, 2021, 1:26 AM UTC

jwally wrote: post #178

johnisgood wrote: post #169

Earlier quoted context omitted.

Of course. Even PubMed is ridden with ridiculous stuff. PubMed! To give you an example: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3068791/ Thankfully we can do our own research, see by whom it has been cited, in what journal it has been published, and so forth. You can easily tell that this is quite an unimportant and incredible one. Of course you could tell it yourself after having read it that it is nonsense.

Are there any guides / heuristics on how a layperson can evaluate technical literature? For example my mother-in-law is starting to micro-dose lithium and cited this article as evidence: https://www.lifeextension.com/magazine/2020/12/lithium-and-a... Which cites 19 medical journals. The website itself reeks of bullshit, but how can I tell if the journals it cites are valid or just woo?

For the record, lithium as a mood stabilizer is pretty solid and settled science in the realm of mental health, which is actually saying a lot as the only other mental health medication that can really claim the same amount of success in treatment to alleviate symptoms would be amphetamines to treat attention disorders. To this day lithium is considered the gold standard in suicide preventative treatment. There is a lot of research that leads to the conclusion that due to the realities of modern civilization we may not receive enough lithium which in small concentrations is is an essential mineral. While I have not read the article you linked to, it may not be that far off base, but may very well be snake oil, nevertheless, the general scientifically held belief is that there is a strong probability that due to modern society norms we do not receive enough lithium in our diet and that the average human would benefit in metal health from a small boost in lithium in their diet. With that stated it is a good reminder that, you can take too much lithium and an lithium overdose has some nasty side effects. It is really something that should be monitored by a doctor as they take blood serum samples and ensure that you are not running high lithium levels which can destroy your kidneys and other organs.

https://www.psychologytoday.com/us/blog/evolutionary-psychia...