If there's no plausible model that involves aliens and explains the observations, it's not science. "Advanced aliens did it in a way we don't understand" is basically a "Goddidit" argument.
I think your view of what science is is a little too narrow. "Aliens did it in a way we don't understand, yet" is a hypothesis, which could be supported or refuted. The famous quote by Asimov is 'The most exciting phrase to hear in science, the one that heralds new discoveries, is not "Eureka" but "That's funny..."'
We've got something funny here, which may be (probably is?) nothing new, or may be exciting.
It is a conjecture or speculation; it is not a hypothesis, in the scientific sense, because without something more than "some way we don't understand", it makes no falsifiable predictions of future observations.
Now, speculation of this type can be the starting point to developing a testable hypothesis, so its not completely outside the scientific process, but it's far sorry of even a hypothesis.
Thanks for the point, I agree if we're speaking precisely and not colloquially. But...
> "its not completely outside the scientific process"
Here you unfairly (imo) diminish the role of wonder and speculation in science, which isn't something at the fringes of it, but part of the very soul and essence of it.
There is an unfortunate side effect of the rationalism movement that the (mostly correct) dismissal of religious explanations and pseudoscientific ideas: A lot of people who should know better also dismiss philosophy, conjecture and other ideas that don't have a firmly established theory as unscientific. These things are an important part of the scientific process. A lot of the key scientific tools and knowledge we have today started out as philosophical riddles.
Ironically, this same mistake has been made time and time again throughout history when science has made great strides. Someone points out that "that's funny", and are immediately shot down for coming up with ridiculous ideas that are not supported by the current theories.
This might not describe OP, but it's a pretty common phenomenon that often shows up in discussions where the boundaries of our current scientific knowledge are close. E.g. AI, the un-observable part of the universe, experiments that seem to break physics (e.g. the RF resonant cavity thruster), what is consciousness, etc.
And for every outlandish hypothesis that turned out to be true there have been a hundred for which a much more mundane explanation has sufficed. As Carl Sagan said, "They laughed at Columbus, they laughed at Fulton, they laughed at the Wright brothers. But they also laughed at Bozo the Clown."
Many of us yearn for novel, exciting discoveries with extraordinary explanations. The desire for novelty is a fundamental part of the human condition, and alien intelligence is one of the most thrilling, evocative, thought-provoking ideas that exist. However, the very fundamental point of the scientific method is to explicitly work against this bias - to ensure we're pursuing the truth and not our pet ideas.
As I brought up in another comment, it is wrong to single out "aliens" in the vast space of hypotheses just because that concept happens to be especially accessible and fascinating to laypeople. There are a plenty of possible explanations that are astrophysically novel and interesting and don't involve such a huge multiplication of entities as the aliens hypothesis does.
>And for every outlandish hypothesis that turned out to be true there have been a hundred for which a much more mundane explanation has sufficed.
A 1% probability of aliens seems pretty significant to me. Obviously it's more likely that it's not aliens, and no one disagrees with that. But the fact that it's even a possibility is very interesting and makes it worthy of investigation.
Anyway there isn't anything inherently unlikely about aliens. You make it like it's incredibly unlikely that aliens exist, so any hypothesis that includes them must be incredibly unlikely. A lot of people have higher prior probabilities on the existence of aliens.
"Aliens exist" and "an advanced technological civilization built a physics-defying megastructure around this specific star" have rather drastically different prior probabilities.
Anyway, I'll give the megastructure conjecture much more weight the second someone in the research community suggests it, preferably with some sort of a testable hypothesis. As far as I know it has been purely layperson speculation and as such not much more plausible than the ramblings of UFO believers or free energy cranks.
> As far as I know it has been purely layperson speculation
Well... almost.
It was originally suggested (as a highly unlikely but testable hypothesis) by astronomer Jason Wright. Then the press completely distorted his original point beyond recognition.
Methods for using Kepler data to identify artificial megastructures is the subject of research by several astronomers, including Luc Arnold (French National Centre for Scientific Research), Jason Wright (Penn State), and Geoff Marcy (UC Berkeley).
Luc Arnold wrote a paper arguing that swarms of artificial structures would have certain unusual signature variations in their light curves. Jason Wright later pointed out that KIC 12557548 had similar predicted variations.
"Now, I don’t know what this is. Maybe it really is an evaporating planet (the best guess, I’d say). ... I’d bet my house on it not being aliens. But given that he went way out on a limb and predicted almost exactly this sort of thing, don’t you think Luc Arnold at least deserved a citation?"
This line, "I'd bet my house on it not being aliens," somehow got picked up by the media as "Astronomers have found super-advanced aliens," because that's how the press works.
So is it all lay speculation? Well, if you just mean credible astronomers aren't seriously arguing for this as a likely possibility, then yes. But if you mean there's no testable way to analyze Kepler data to distinguish between artificial and natural satellites... well... work in progress.
Given that none of the natural explanations seem to hold water, I don't think it's unreasonable to consider the possibility of aliens. After all, many respectable astronomers have pointed out that the sheer number of stars makes it highly unlikely that aliens don't exist (well, there's still a lot of room between "alien life" and "alien civilization", but even the latter is a real possibility), and if they do, their blocking the light of their sun might actually be the most likely way we might detect them. (SETI by radiotelescope seems very unlikely to detect meaningful signals.)
So given that aliens might exist, and this might be the most likely way for us to detect them, it's certainly possible that it really is aliens this time.
Of course we don't know for certain. Not by a long shot. It is absolutely speculation, but it's reasonable speculation. We probably need a lot more data before we can say anything more specific about this. Maybe we do find a natural explanation after all. But it's not reasonable to ignore this possibility because some people don't want to discuss it.
And the person who proposed this is a real astronomer. Of course he didn't say it's definitively aliens. He said it's a real possibility. That doesn't mean a lot (because it's technically true of any star or exoplanet), but it's the most likely case we've got. And that's worth some attention.
>I'll give the megastructure conjecture much more weight the second someone in the research community suggests it, preferably with some sort of a testable hypothesis
Neither of those things should increase the probability at all. Just because a researcher believes it doesn't make it more likely to be true. Neither does the fact that it's testable.
Conversely, you shouldn't lower the probability because those things aren't true.
The Bayesian interpretation of probability is that it is a measure of subjective uncertainty. As such, a plausible model proposed by a credible member of the scientific community very much gives me a reason to update my priors.
Technically, a scientific hypothesis requires it to be testable. Given this is at least partially scientific, the person saying it is a hypothesis should probably present a way to test if it is true or not. Given we don't know how to test for it yet, we may be left with continuing to explain what it is we're seeing without saying what it is. Which, I suppose, is a big challenge with space based discoveries.
> It is a conjecture or speculation; it is not a hypothesis, in the scientific sense, because without something more than "some way we don't understand", it makes no falsifiable predictions of future observations.
But it is falsifiable, for example we could falsify it by visiting the star and observing that there is no life in its solar system and no artificial satellites orbiting the star.
The "nothing new" vs "aliens" is a false dichotomy. It might be a zillion things that are novel and exciting astrophysically but do not involve aliens or completely new physics. Heck, there are novel and exciting things on Pluto that we don't completely understand but no sensible researcher is shouting "aliens"!
If it's not different, it suggests that you believe the chance of the existence of god is equal to that of there being advanced alien civilizations with technology beyond our comprehension.
Neither does anything in the way of real explanation, but if you believe that advanced alien civilizations are likely to exist (which is a fairly defensible argument based on things we DO know) or have existed (depending on how far away what we're observing is), the likelihood is quite different.
If that's true why do scientists take seti seriously and ask to increase its funding?
The attitude has always baffled me in fact. We constantly say that alien life is likely due to the size of the universe yet we can't use them as an explanation for observed phenomenon.
A hypothesis that makes testable predictions is perfectly valid science even if it involves aliens. "Aliens did it" in itself is not a scientific explanation. Aluen life is probable a priori just given the size of the universe; unfortunately we also have all sorts of other evidence that technological alien civilizations are nowhere near us.
With SETI, we explicitly make the assumption that any prospective aliens are using communications technology that can be intercepted by us.
That's what I suspect. From what I understand, we wouldn't be able to detect our own radio broadcasts from more than half a light year away. The only realistic way in which we might detect alien radio signals is if they were either really close, or they're using a focused beam aimed directly at us. Which would imply they know we're here and listening. It all seems a bit unlikely.
Detecting alien megastructures, though, there might be something to that.
Extraordinary claims require extraordinary proof. That's why you'll see researchers working hard on all of the ordinary explanations of an observation, for a long time, before entertaining an extraordinary explanation.
"A plausible model" is the key phrase. There's a huge difference between postulating that aliens might exist and produce radio broadcasts (something which we can already do, and understand very well) and that aliens might exist and be able to not only build something larger than a hundred planets, but build it in ten years. We don't even have a theory about the sort of engineering that might be required for that--it's pure speculation. And that's the problem.
I think my argument still stands, though--even a hundred years for something of this scale is beyond any science we can reasonably hypothesize about. Doesn't mean we can't speculate, just that it's not terribly constructive speculation.
There is a difference between claiming that aliens have done something, and being critical of those too dismissive of the possibility.
This isn't goddidit. That argument is used to end a debate, to say that the how is unknowable. A claim that aliens are doing something is the opposite, a call for more careful and complete scientific scrutiny.
Eh, outlandish hypotheses can be worth exploring once they exist as scientific hypotheses, i.e., when there is something that forms a basis for a falsifiable prediction, even if more mundane explanations haven't been rejected.
OTOH, "aliens did it by unknown means" is experimentally undistinguishable from "it happened by unknown mechanisms" more generally, and untestable.
If you assert that no intelligent extraterrestrial entities are capable of harnessing, redirecting, or otherwise manipulating the light from a star, then you have a burden of proof of your own to meet.
In Occam's Razor terms, "super-sophisticated aliens did it" is just about the most complicated answer with the most "entities" conceivable. It is a great deal simpler to hypothesize that we've missed some aspect of stellar dynamics that fits the observations. This is further boosted by the fact that we have a history of such things (pulsars, etc).
It may be true, but it is definitely a hypothesis sitting on the bottom of the list of sensible possibilities. Any rational analysis pretty much has to put "our understanding of stellar dynamics is missing something" multiple orders of magnitude more likely, given our current state of information.
In Occam's Razor terms, "super-sophisticated aliens did it" is just about the most complicated answer with the most "entities" conceivable.
Occam's Razor isn't a nuclear weapon. You still have to decide which entities are necessary and which are superfluous, presumably through some insight into the underlying premises.
In this case we simply don't have the perspective we need to decide what's "outlandish" (to use Sharlin's term) and what isn't. What's inherently outlandish about aliens? We're aliens, too, from the perspective of every other civilization that might exist.
See my other post -- some very credible authorities would say it's surprising that we haven't found evidence of any ET civilizations, given the number of possible habitats for them. What's almost certain is that the only such civilizations we could observe are the few who can deliberately alter the appearance of a star. Not only is it scientifically inappropriate to reject "Aliens did it!" as a hypothesis or to assign it an arbitrary (un)likelihood, but IMO we shouldn't even be surprised if that turns out to be the case. Alien civilizations are, or should be, no big deal.
Occam's Razor is a heuristic, not a law. I think you're misunderstanding what it is. It doesn't mean aliens are impossible. It means the rational conclusion based on the evidence puts the probability of aliens very low. This is because, on the evidence we have right now, we know we are far more likely to be missing some quirk of science than to be finding aliens, because we have on multiple occasions found we've been missing out on science. We don't need aliens to explain this yet.
Show me a coherent information signal coming from this star and I'll change my tune in a heartbeat, but "the brightness of this star is behaving a bit oddly" just isn't that spectacular of a signal.
The aliens are superfluous entities because "aliens did it by unknown mechanisms" has no additional explanatory power than "it occured by unknown mechanisms."
Depends on the question you ask. "What's interfering with this star's light?" is one question. "Can we find evidence suggestive of any other civilizations, specifically the kind who could build Dyson spheres?" is another.
There's plenty of "burden of proof" to go around, I think. That's what makes this such an interesting (if futile) question.
It comes down to the amount of surprise we should experience at finding evidence of any ET civilization. Arguably, given the sheer number of other worlds that we now know to exist, it's surprising that we haven't found any such evidence.
At the same time, given the vast distances involved, it would be surprising if any evidence that we might find didn't consist of something truly unusual and spectacular on a stellar scale... something like a Dyson structure that only one in a million civilizations might be capable of creating. With our current observational tech, we'd never notice anything less.
In the OP, Sharlin used the term "outlandish." That's a value judgement, not a term of art. It's a judgment we're not qualified to make.
