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Shrike


				

				

				
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joined 2023 December 20 23:39:44 UTC

				

User ID: 2807

Shrike


				
				
				

				
0 followers   follows 0 users   joined 2023 December 20 23:39:44 UTC

					

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User ID: 2807

You asking for me to provide debunkings of claimed medical miracles is an great example of backwards thinking on how to go about evaluating claims of supernatural occurrences.

What I am actually asking for you to do is demonstrate that you've actually looked into the question at all. There's nothing wrong with not looking into miracles (I haven't, not really something I am all that invested in) and I certainly don't expect you to just to win an argument on the Internet, life's short. But "no religious believer has done a very good job of getting a miracle recorded, or proving faith healing works" suggests that you speak from a position of personal knowledge. If what you meant was "I've never heard of any religious believer saying X, Y, Z," then that's a different claim, and that's fine. But if you've actually looked into the question extensively and documented your findings, I might be interested in reading your conclusions. If you haven't looked into the question, why are you making the argument? It seems to me that arguments from ignorance only incentivize not knowing anything, and while arguing about Nietzsche on Twitter is funny, it's not really an ideal epistemic environment.

Weird shit happens all the time, but that doesn't mean it's a miraculous event from the Power of God

I agree with this.

No study has ever demonstrated miracle healings working.

What exactly qualifies as "miraculous healings"? Do studies showing that prayer seems to expedite healing count? Spontaneous remission of cancer? Regrown arm?

There's a million dollar prize by James Randi for a demonstration of any occult power under laboratory conditions.

No there is not, but you should also understand the difference between alleged miracles and occult power.

There are tons of religious hospitals, why don't they have a track record of better outcomes than the secular ones?

Are you unfamiliar with the research showing the positive connection between spirituality and good health outcomes?

Anyone who could actually demonstrate a new power of healing or prediction or weather control would become immensely famous and presumably very wealthy.

Miracles are not the same thing as superpowers. The debunking of a claim to be able to work miracles cannot prove that miracles do not occur (and, similarly, proof of a miracle would not be evidence of superpowers.)

People used to take pictures of UFOs. They weren't really aliens.

Yes, UFOs =! aliens. In fact, many of the leading "UFOlogists" think that UFOs aren't really aliens.

Yet the evidence never seems to get better.

What's your objective metric for this claim?

Note that some portion of UFO claims were in fact US military aircraft, so it's really ironic you bring that up.

Yes, I am aware. In fact a certain portion of the UFO phenomena may be cultivated by the US government precisely to hide advanced aircraft.

If aliens were such advanced fucking space creatures capable of spaceflight then presumably they'd be even more impossible to detect than NGAD if they so chose.

Then why did you make this argument at all?

If there were something really there, at some point we'd expect strong evidence to emerge. People are certainly highly motivated to look.

This is also true of next-generation aircraft.

That's not what I recall from my reading on the topic, or - to be clearer - at least not in the Anglo tradition. I'd be very interested in contrary sources!

I suspect Orthodoxy is in the unenviable position, though basically no fault of its own, of attracting a certain type of person who thinks that their youth pastor and Pope Francis were both not hardcore enough.

Historically wasn't the median age gap for first-marriage something like a few years, though? I'm not aware of any era where the historical norm was, like, 19 for women but 27 for men.

Articles like this can be really interesting windows into small subcommunities, but they aren't really a replacement for broader data, which does show that faithful religious attendance does correlate with a lot of modernity-resistant behaviors. (For instance, Haidt found that practicing religious teens handled the onset of smart phones well compared to irreligious ones, even if they were still negatively affected.) So reading this and drawing the conclusion that religion doesn't in fact have good effects that protect against modernity is wrong.

I don't think it's all that original of an insight to say that in real life the modernity-resisting "trad wives" aren't wearing long dresses and posting shots of themselves in fields on social media, right now if they aren't asleep, they are probably wearing jeans and a t-shirt and cleaning up some sort of bodily excrement or cooking food. They may not conceive of themselves as "trad wives" at all, they go to an nondenominational, Baptist, or Catholic church and probably not a particularly "trad' one, listen to podcasts and contemporary music, have an iPhone, enjoy watching Marvel movies, and probably do not live on a farm. They might not particularly feel like they are winning the battle against modernity now, but over the long run they are having more kids, longer, happier marriages, and a more satisfying life precisely because they aren't posting glamor shots or snippy Substack posts.

However, I do think this post highlights a potentially real problem: people turning to "trad Christianity" (or any other religious practice) because they want to post about it on Twitter or Substack or because they want to find a hot wife/tolerable husband and not because it's true, looking to get something out of it for themselves first, probably aren't going to find what they are looking for, and they're likely going to undermine whatever community they are going to be a part of. I'm not saying religious groups can't work with these types: they can and they should. But it makes one wonder if the future of religion is more gatekeeping, not less.

This doesn't necessarily mean that "traditionalism" isn't a viable solution for individuals, only that it doesn't scale. (Of course the reason Amish/ultra-orthodox isn't a viable solution for most individuals is that part of the trad solution of both groups is insularism.)

In contrast, no religious believer has done a very good job of getting a miracle recorded, or proving faith healing works. Some religions believe their priests have the Power of God, but they can't seem to demonstrate it.

Can you link me to your past examination of medical investigations of alleged miracles demonstrating where they break down?

There's the same documentation problem for UFOs and Bigfoot: high resolution cameras are in everyone's pocket for a decade+ now and yet we don't see increasing evidence.

As I've pointed out to other people on here, we know that certain aircraft (like the NGAD demonstrator) have flown but have never had a high-resolution picture taken and publicized. Do you also disbelieve in the NGAD, or do you concede that it's possible for aircraft to fly without being detected by cell phone cameras? If the latter, why are you making this argument as pertains to UFOs? (I think it's a better argument as regards Bigfoot.)

Doesn't it alternatively suggest that supernatural phenomena are real and universal?

That's something that many, perhaps most, religions would agree with (i.e. it doesn't invalidate or privilege any specific religion.)

Speaking very generally, as the rate of fire of a firearm increases you quickly hit diminishing returns and then get into negative gains.

Maintaining a broad right to keep firearms in your own home, but restricting your ability to carry them in everyday life, seems potentially in the spirit of the Second Amendment if you understand it in terms of a people's insurance against tyranny.

In the Second Amendment the two rights ("to keep and bear arms") are listed together.

So yes, they're dangerous enough that you'd want to grow, and a sufficiently advanced civilization can also harden itself. Both can be true.

But there's no evidence that hardening against RKVs requires K2 levels of energy. If the Sierra Club's lawsuit against the Dyson sphere succeeds, we're not doomed to be struck by RKVs. Furthermore, as discussed previously (and also below) a Dyson sphere isn't even the best method of energy collection.

It's worse than trying to blow up an asteroid with a nuke, because the debris cone can do nearly as much damage as the intact projectile.

If you are really worried about this, you can use a laser or similar system to ablate them so you can move them off-course in a predictable way.

A Dyson swarm has to dump waste heat somewhere.

Yes, and from what I understand, it is also unstable if sufficiently dense.

That is a ridiculous amount of engineering effort, for not very good reason.

This also describes a Dyson swarm to begin with. If you're going to go to a ridiculous amount of engineering effort, for not very good reason, you may as well keep going!

GAH only needs one civilization, anywhere, in the entire history of the observable universe, to launch them.

No it doesn't. Self-replicating devices with short doubling times already exist, but they have not eaten the observable universe despite trying. In addition, plenty of things with (probably) much lower floors for "happening" haven't happened.

But what would I actually do? Walk there. It's 10 seconds away.

Notice that you employ this argument selectively: civilizations will build Dyson swarms because it's the best idea, but launch VNRs even though it's a TERRIBLE idea. But maybe we live in a universe where the opposite happens: civilization don't launch VNRs because it's a bad idea but they don't make Dyson swarms, either, even though it's a good one.

The strength of GAH is that the absence of the signatures it predicts genuinely is strong evidence, because the assumption set is minimal. All you need is: STL interstellar travel is possible, and at least some civilizations will use available resources over geological timescales. That's it.

For the GAH to tell us anything about the universe, it specifically requires assuming that technological progress will arrive at "can build Dyson swarms" and stop there. If it turns out that the most efficient way to harvest energy is by the care and feeding of your own black hole then we'd never notice the stars being blotted out.

And yeah, I'd bet that the black hole is actually preferred by truly advanced civilizations:

  • you're not stuck to a star (it's mobile)
  • inherently scalable
  • occasional lawsuits from the bereaved kin of the sphagettified will not fail as a business strategy, whereas the environmental lawsuits from darkening the sun will not
  • much more efficient energy extraction process

So yeah, if we just assume advanced aliens prefer to use more efficient energy gathering methods then we won't observe them (or at least not by looking for stars being eaten). Waste heat isn't hard to move around (or put to work) so I am not sure we'd see that, or even know if we did see it (my understanding is that there are plenty of odd IR signatures in space.)

Now, maybe it turns out that artificial black holes are ~impossible to create (right now our estimates are that creating one artificially would be extremely difficult) but if it's doable then you would expect that to be preferred.

The fewer joint assumptions, the better the explanation, and "no one is here yet" is just the cheapest fit.

I tend to agree that it's the cheapest fit, I just don't find the GAH very persuasive, because it seems to me there is a lot of uncertainty around it, and from what I can tell about our own future trajectory as a species, we are not on the path to creating the technosignatures in question.

It was more like 4 or 5, wasn't it? 2 tankers, 2 or 3 destroyers?

All Operation Project Freedom proved is that they won't be able to get the 1600 ships that remain stuck in the gulf out before Trump's term ends at this pace

This does seem unlikely, but the incentive structure that seems to be forming (ships not participating in the scheme get hit) would work to Trump's favor, if Operation Project Freedom was something we were doing, which it isn't, unless of course it is (I dunno I haven't checked the news this afternoon).

In other words, the only thing likely to get the strait open is an end to the war.

Fundamentally I think this is correct. But it does appear that the US has a substantial military ability to protect tankers going through the strait. And there were, as I seem to recall on earlier Iran threads, strong suggestions otherwise. So I think it's interesting, both militarily and from the perspective that it theoretically allows the US to, however marginally, ease the constraints on them, while maintaining the constraints placed on Iran.

Worth noting that the Namu, as I understand it, had been in the Gulf since the start of the war and was not attempting to transit the straight under US protection when it was hit. Apparently was instead anchored offshore when it was struck. It also doesn't seem clear that Iran actually hit it (at least intentionally – apparently they denied the claim they had attacked it.)

Another good example. People forget how completely low light environments absolutely neuter cameras!

I am extremely confused by accusations that I haven't addressed the downsides of indiscriminate RKV spam, particularly if you're targeting systems with budding civilizations or near-peers.

Either RKVs are dangerous enough that you should expand out in space as quickly as possible to defend yourself against them because people will fire them off indiscriminately, or they aren't actually all that dangerous and so there's no rush to expand. We both seem to agree that firing off RKVs isn't actually all that great of a strategy, so it doesn't make sense to try to be grabby specifically to survive RKVs.

As I've mentioned elsewhere, a sufficiently fast RKV will appear barely any time after the light that came off it.

This sufficiently fast RKV will never arrive, because it will hit a piece of interstellar dust and vaporize. If you're worried this won't happen, you can make sure of it pretty trivially as a defensive measure by creating armor belts of small high-density particles, which is going to be considerably easier and cheaper than making an RKV kill chain.

Any RKVs that travel at a more leisurely pace to avoid obliterating itself will likely be detected by any "peer" civilization and intercepted by another RKV of some kind, or a high-energy laser or particle weapon that will ablate it and push it off course.

None of these defenses are technically hard; some of them could be probably be accomplished by civilizations below K1 on the Kardashev scale. (For reference, the interplanetary dust cloud - which is thick enough that dust strikes are routine on spacecraft - has less mass than a relatively unexceptional asteroid).

At the bare minimum, you should harvest that.

Why? If you've decided to wait until the end of the universe to crunch numbers then you might as well just wait until then to do everything.

You forget that you can extract rotational energy from existing black holes with remarkable efficiency (compared to most power sources). It's easy. You just have to drop mass in the right way.

Uhhh, here's what I in fact said:

By creating a small black hole and feeding it mass, you now have an extremely efficient method of both energy production and propulsion.

I think you may have just skipped over my most interesting proposal for an Aestivation civilization. Sad! I thought it was neat.

They'd have eaten the whole thing and sent probes and VNRs our way.

Sure, and this might have already happened and we just don't happen to know it!

VNRs are trivial to the kinds of civilizations we're discussing.

VNRs are considerably more complex and far-fetched than solar-sails, and, just like separatist expeditions into space, an inherently dangerous technology that a smart civilization would think twice before launching.

You demand that every civilization convergently decides to become a hermit. They is really not a good argument.

Not at all, my argument (which I am mostly making for the case of intellectual honesty since I too am skeptical that life elsewhere in the universe is abundant if it exists at all) is that there are a multitude of reasons why there might be aliens in the universe that we have not observed, and thus the inference from not seeing them is not especially strong.

Including, hilariously, that they've already converted most of the galaxy to Dyson swarms and we don't know that because they routinely divert a tiny fraction of their energy into masking their position from any planet with biosignatures. You say it would be pretty trivial to detect those planets via inferential telescopic means at ludicrous ranges and take seriously the idea of a Nicoll-Dyson beam; very well, I find those sorts of megastructures very far-fetched but if you're going to the trouble of making one and have the technical means to do it, you likely also have the technical means to trivially prevent planets you've detected with biosignatures from noticing via selective emissions or laser masking.

"Grabby aliens" is only one path out of thousands for a society to take, and the fact that we have not observed it being taken is not particularly strong evidence that it hasn't happened, let alone that the other thousands of options have not been pursued.

The short version is that the US has announced and then called off a program to send vessels through the strait, during which brief window they successfully transited both warships and civilian vessels through the strait. (There were rumors that at least one Gulf State was not a fan of the escorted transit plan and pulled or threatened to pull basing access, and that's why the US flip-flopped). The US also blew up a bunch of Iranian military assets that tried to attack them or were otherwise deemed a threat, and interdicted several Iranian tankers that were trying to run the blockade with Super Hornets. Despite this of course the ceasefire is still on, we're assured!

The cynical part of me wonders if all of this hasn't been a bigger part of the news cycle because despite the embarrassing rumors that the USA and its allies got crosswise on how to approach the situation, or the humorous claims that the US attacking a bunch of Iranian assets was "just a love tap" and not a resumption of the conflict it is more or less good news for the Trump administration militarily; it suggests that Iran actually does not have a good grip on Hormuz if the US can escort civilian shipping and handily fend off attacks.

You just made a big long argument that RKVs are so cheap that you could sterilize the entire universe but also that RKVs aren't cheap enough to destroy every possible outpost made by a civilization that made something as obvious as a Dyson sphere.

Now, setting aside the fact that this does actually explain the Fermi paradox (a prior civilization targeted every planet that was then capable of supporting life) you completely failed to address the downsides of spamming RKVs in universe where there may be civilizations that can produce RKVs: they are 1. likely noticeable because of the heat signature produced by relativistic speeds, even against interstellar particles, and 2. very easy to intercept with other RKVs or lightspeed weapons, and 3. not likely to be reliable against targets at long ranges because any minute error (including errors introduced by unexpected gravitational forces during the intervening travel time) will cause it to miss.

There are ways to mitigate these problems but RKVs are not good weapons against any civilization that might be able to shoot back in the next [distance away in light years] years. Since it is more energy-efficient to defend against them than to attack with them, we would not expect them to be utilized en masse among peer civilizations.

Aestivation without collecting resources?

Why would you collect resources when the universe will do it for you? Stars won't be very energy rich near the heat death of the universe, but Sagittarius A* isn't going anywhere, and will likely continue to grow until after the stars burn out (remember, black holes can grow from cosmic background radiation), until the expansion of the universe places all objects and radiation beyond its gravitational reach forever. You could park yourself in orbit and run calculations off of a black hole (which emits tremendous amounts of radiation as it consumes matter, and tiny amounts as Hawking radiation) for an infinitely long amount of time. This would likely be more efficient than building Dyson spheres throughout the universe; Sagittarius A* has the mass of about 4 million stars and is growing. Right now it would take vastly longer than the age of the universe for Sagittarius A* to evaporate due to Hawking radiation. And because Hawking radiation grows as the size of the black hole gets smaller, it seems arguably perfect for such a plan, since you will be maximizing energy collected at a point when the universe is the coldest. As time goes on and the universe grows colder and your calculations grow more efficient, you also gain more energy to calculate with.

The main objection to this plan is that the Hawking radiation output on a supermassive black hole is too negligible to power anything, but I am not sure this holds true if we are orbiting near the event horizon with our Dyson swarm, due to time dilation. (Also you get fried with gamma radiation when the black hole collapses, but whatever, surely you've finished your big math problem or whatever by then.)

However, this is only the second-best plan involving black holes. By creating a small black hole and feeding it mass, you now have an extremely efficient method of both energy production and propulsion. You could (in theory, if you can do the math right) travel around the entire universe at relativistic speeds and feed 100% of the mass into your black hole, directly converting about 25% of it into energy to run your calculations with.

Since our entire point is hibernating until the universe is colder to do the math, the best time to crunch the numbers and figure out how to do this is after the universe is already dying. You'd only need a small "bootstrap" energy source (which might even be something as trivial as a fusion reactor) to run your calculations at that point. Of course, you wouldn't want to gamble on this unless you were pretty sure a black hole starship was possible.

Fodor's take is braindead. Yeah, sure, we can digitize and live in VR. Doesn't stop space probes and VNRs from being sent out. That is the default expectation.

Fodor explicitly discusses this, which tells me you've dismissed his take as "braindead" without bothering to read it (which you can do here). Even if he was wrong about the space probes, it's pretty clear that a society that virtualized at, say, 2200 levels of human technology wouldn't really need to expand to have all the energy they could ever need, and any probes they sent would be much less conspicuous than a DYSON SPHERE.

All you need to accept is that STL interstellar colonization is possible, and that most species would want more resources, especially if they're easy to acquire.

I would argue that you actually have to accept that most species will pursue ~limitless resources that they don't need, which is a harder pill to swallow. If we assume as a default that most species have no access to contraceptives, this makes sense. But if something like the human experience is the default, we can expect most species to grow slowly if at all by the time they need to colonize other worlds because they will be able to control their own reproduction, and they will not maximize the pursuit of energy resources simply for its own sake (we certainly do not do this on Earth). They will have zero reason to construct anything like Dyson sphere, as they will have no need for the energy. Furthermore, colonizing other star systems without cracking the lightspeed barrier is a very dangerous idea, for obvious reasons: your first concern shouldn't be aliens, but members of your own species developing their own culture in a technologically advanced parallel socio-political environment. No sane species would permit this by default without some sort of constraints. We should expect most species to, at least while their star is still burning, to centralize their civilization around their star system, which will have enough resources for practically limitless numbers of their society without anything besides modest engineering (such as space habitats), and actively inhibit attempts to leave by would-be splinter societies.

This council produced and agreed to the Arian formulas that, "the Son is like the Father according to the Scriptures" and "the Son is not a creature like other creatures."

Didn't this council (which was minority Arian) specifically and explicitly affirm the Nicene Creed and the Dated Creed only had any hold because the Emperor held them in Constantinople after the council was ready to adjourn?

Whatever beneficent role Pope Liberius played here, it does not seem like he was checking a genuine majoritarianism on the part of the bishops, unless I misunderstand something.

the compelling ideological scenario to maintain secrecy isn’t really there

Keep in mind that the allegations out of the former US government personnel pushing for "'disclosure'" are that the parties responsible for maintaining some of this information may have committed crimes or at a minimum failed to be entirely transparent with Congress.

If you are the executive branch (just setting the NatSec question to the side for a moment) your incentives for unraveling the secrecy about a historical program like this are very complicated. You might want to disclose stuff to make yourself look good, or your political foes look dastardly. You would think very carefully before disclosing something that ran the risk of Congress passing the Ending Insane Executive Power Overreach Act of 2026.

Which is consistent with what we're seeing out of the executive now (a drip of documents, blurry pictures and video, nothing particularly politically interesting). But of course that's also consistent with the government not really having anything politically interesting to begin with.

If anything spicy does start to come out, pay close attention to how much of it is oh-so extremely historical.

we need a good explanation for why there's such an abundance of untapped negentropy in the wider universe

There's no shortage of such good explanations, such as the Dark Forest Theory, the Aestivation Hypothesis, and of course Greg Fodor's Intraterrestrial Hypothesis (which of course if expanded universe-wide would explain very neatly the lack of mega-engineering.) "Grabby aliens" is just one model of how advanced alien species might behave based, essentially, on pre-modern human behavior.

I will concede that even JWST probably couldn't detect the thermal signatures, assuming the craft coasted in after doing the bulk of the braking by 10 AU away.

And this is exactly the sort of arrival by aliens we should expect if they don't have exotic space propulsion. Some sort of solar or magnetic sail, from what I can tell, is just a more efficient way of traveling long distances than a nuclear rocket. Fewer moving parts and chance of malfunction, too.

We're still requiring a model of alien psychology that has to reconcile some very questionable behavior

To be clear, I do not think that it needs to follow AT ALL that because some of the stories from e.g. fighter pilots and intelligence personnel are true, that all the stories of alien abductions are true. Similarly, even if every single story of alien abduction is true (as understood by the people telling them) I don't think it follows necessarily that any of the strange UFOs/UAPs spotted in the sky and undersea are alien in origin.

If they are here, why do they act in a manner that's just at or below the threshold for robust detection by our ever-improving detection capabilities?

According to who? The narrative from former intelligence/DoD/CIA types is that they very much can be tracked (but that they exhibit evasive behavior/attempts at "signature management"). Are you unaware of the "range foulers" that appeared when the Super Hornets got their AESA upgrade, of the declassified US documents discussing a potential UAP spotting via a satellite, of Ratcliffe talking on national television about corroborating UAP tracks from multiple sensors, of the "UAP detection mode" on the S-400 discussed by a former CIA analyst...?

If your argument is "why aren't they detected by civilians," where's the clear photo of NGAD? Of the SR-72? We know (or at least can assess, in the latter case) they were built and flown. The RQ-180 flew operationally for probably a decade before really clear footage was taken of it by civilians. It's not hard to prevent civilians from taking slam-dunk evidence that something exists. Even large organizations with significant amounts of institutional incompetence can do it routinely.

Why are they here?

If we detected atmospheric signatures that strongly indicated life in any star within, say, 40 light-years, I think we would attempt to launch a probe to investigate sometime within the next 100 years. Nothing that we put on that probe would be authorized to speak for us in any binding sense (although of course we might opt to put some golden records or something on it).

Which, if you think about it, would explain fairly neatly the behavior we've witnessed:

  • Evasive objects that act defensively (including jamming and evasive maneuvering) when confronted
  • The long-established connection between UAPs and the ocean (and nuclear testing)
  • The reported "humanoid" bodies and the abductions
  • Yes, even the technological "pacing" that seems to occur

I don't think there's a monocausal explanation for UFOs, and due to the numerous reports from many angles of what seems to be what might be termed a "spiritual" dimension to them, I tend to suspect part of the true explanation is even less prosaic than modestly advanced aliens from a nearby world. But I try to think through the possibilities with an open mind, and I don't think the broad outline of the reported behavior is very odd for an unmanned scientific mission. And yes, I don't see any tension between an unmanned scientific mission and the reported acquisition of "bodies." Even granting that an advanced civilization saw a bright line between biological and mechanical entities the way that we do, biological entities could be helpful at accomplishing various aspects of the mission, and there's no law of physics that would prevent them from being put together at the destination, or prevent them from utilizing the biological makeup of the native life, adopted as it conveniently is to its native environment.

I think the natural phenomena explanation is more likely. (Like I said, I don't think we've actually spotted Dyson swarms.) But the truth is more complicated than "oh well we would know if they were out there." The fact that we might know if someone built a Dyson sphere tells you something about how much we don't know.

A civilization with the technology to build even one should be in the process of a Grabby Alien takeover of the lightcone.

Maybe - I don't actually think Dyson sphere are very likely to be built, even by an advanced spacefaring civilization. Swarms are slightly more likely, but even then I don't think the fact we haven't spotted them. And I don't actually think the scenario where Grabby Aliens start making Dyson Swarms in the entire galactic neighborhood is a given, either.

overwhelmingly tend to turn out to be well explained by natural phenomena?

You've found one paper arguing that one candidate is explained by natural phenomena. I think it is most likely all of them are explained by natural phenomena but, again, what sort of argument is this?

"We can say confidently there's no aliens because we looked for one extremely difficult to build megastructure of questionable plausibility, found multiple potential matches and we're pretty sure one of them is explained by a natural occurrence" is just a bad argument. I would bet every single one of these SETI findings is due to some natural occurrence, but that doesn't make the argument good!

You're getting some replies saying "why wouldn't we see them in space" so I'm dropping this note to remind everyone that SETI efforts have indeed found stellar signatures broadly consistent with stellar engineering.

Do I think that's what we've spotted, personally? No, not really. Do I think "we haven't spotted any candidates for technosignatures, so there aren't any" is a good argument when we have spotted candidates for technosignatures? No, not really.

Obviously I definitely think it's possible for a group of people to keep a secret (...most corporations do this!) but I also don't understand the entire line of argumentation that holds "these whistleblowers must be wrong because if they were right somebody would blow the whistle" (!??!?!!?)

Deceleration without getting caught is the hard part, especially if you aren't going to dramatically lengthen the journey in the process.

No it's not, you can e.g. decelerate from nearly .5C over the course of about 20 years with a magnetic sail.

There is very little justification for aliens that advanced to go to all the bother and do... whatever they're presently accused of doing.

This is an odd objection to me given that the "aliens" in the conventional narrative supposedly act exactly as humans do towards, say, apes (trying to observe them discreetly but slipping up in embarrassing ways, occasionally knocking them out with mysterious weapons and taking biopsy samples or tagging them, doing hybridization experiments, etc.) and if anything that seems suspiciously anthropomorphic. It seems to me we should expect aliens to behave weirdly, if they were truly from a distant world in some way.