Manufactured crises

A very nice piece by Ethan Siegel, on which I will offer just a few thoughts.

The big problem that many non-scientists (and even some scientists) will never realize is this: you can always contort your theoretical ideas to force them to be viable, and consistent with what's been observed. That's why the key, for any theory, is to make robust predictions ahead of time: before the critical observation or measurement is performed. This way, you can be certain you're testing your theory, rather than tinkering with parameters after-the-fact.

I have to add that sometimes you don't know exactly what it is your theory predicts ahead of time. Most ideas grow in response to one specific problem, rather than being forced on you by multiple lines of evidence. It's only later that you get to test the idea against areas that were never considered during its inception : there are implicit assumptions you weren't aware of. So most ideas that work well for that one single issue have to be rejected because they are fatally contradicted by other arguments. This means it's very hard to avoid tinkering with the model later on; this can be entirely legitimate, but things quickly and inevitably get messy.

The key to cutting through all this is to focus on the key aspect of the theory, to try and test as much and directly as possible the most fundamental component of it, and not confuse this with more nuanced aspects like the particular value of one parameter.

For example, the standard model of cosmology depends on the notion that most of the mass in the Universe is undetectable. It's not at all implicitly obvious from this lone statement what this applies for galaxy formation. Can you tell me, simply based on this and nothing else, how galaxies assemble and evolve ? No, you can't. And thus we're sometimes told that observations like downsizing, the missing satellite problem, the Tully Fisher relation etc. are all evidence against dark matter, whereas in fact it's more likely that they're only evidence - if at all - against highly specific aspects of the galaxy formation model. That's a very different prospect.

(Writing up a more detailed piece as to how the problems with dark matter are related to implicit assumptions has been on my to-do list for a while. I'll get around to it eventually.)

That's the key that's so often overlooked: you have to examine the full suite of evidence in evaluating the success or failure of your theory or framework. Sure, you can always find individual observations that pose a difficulty for your theory to explain, but that doesn't mean you can just replace it with something that does successfully explain that one observation. You have to account for everything, plus the new observation, plus new phenomena that have not yet been observed... That's why practically every working scientist considers these proposed alternatives to be mere sandboxing, rather than a serious challenge to the mainstream consensus.

Not that there's anything wrong with spitballing - luck plays a key role in which ideas survive and which have to be cast aside. A good idea requires intelligence, but no-one is so intelligent that they can see straight away that their idea solves all the problems. Speculation and considering alternatives are fundamentally good things and to be encouraged. The difficulty comes not from freewheeling, playful speculation, but when people stop playing around; when they refuse to acknowledge that their idea doesn't work, or, equally, that someone else's idea does work.
Saying, "I've just had an idea" is great.
Saying, "I'd like to see what the community thinks of this, here's a paper" is great too.
But saying, "this idea clearly shows I'm a genius and everyone else is stupid", mistaking legitimate, necessary speculation for actual advancement, is not nice, and we'd be wholly better off without it.

On the other hand, we might not be able to avoid it. The consensus is only the consensus because it survives repeated attacks such as these without persuading more than a handful of people that it's wrong. While you can't decide truth by majority, the problem is that no-one really seems to have much of a better idea as to how you do establish truth (an immensely difficult philosophical problem). And a consensus without alternatives is no consensus at all, so having to endure a handful of intelligent people who doubt evidence that seems to everyone else to be incontrovertible, well, perhaps that's just something we have to live with.

But we mustn't forget or throw out the existing successes of General Relativity, the expanding Universe, the Big Bang, dark matter, dark energy, or inflation. Going beyond our current theories includes — as a mandatory requirement — encompassing and reproducing their triumphs. Until a robust alternative can reach that threshold, all pronouncements of "big problems" with the prevailing paradigm should be treated for what they are: ideologically-driven diatribes without the requisite scientific merit to back them up.

Yes. And it's far easier to amass interest if you say,
"ALL OF SCIENCE IS WRONG AND THEY'RE ALL JUST A BIG BUNCH OF ARSES" 
than if you say,
"ALL OF SCIENCE PROVISIONALLY CORRECT BUT MORE TESTING IS NEEDED FOR FURTHER INCREMENTAL IMPROVEMENTS, LIKELY LEADING TO AN EVENTUAL PARADIGM CHANGE AT SOME POINT, AS IS THE ENTIRELY CORRECT AND PROPER METHOD OF ORDINARY SCIENTIFIC ADVANCEMENT."

Disagreement between scientists is necessary. But the survivorship-biased narrative that's given to the public is just stupid. If a million monkeys have a million ideas, some of them will be better than others. If one of them gets lucky and has a good idea, that doesn't mean that monkey was anything other than a lucky monkey. Not even if said monkey was resolutely convinced of their idea and dismissed all the other monkeys as being too stupid to see it, because all the other monkeys probably said the exact same thing.

That doesn't means that some monkeys aren't more intelligent than others either. But there will be far fewer clever monkeys than stupid ones, so it's entirely possible that one of the stupid ones hits on a good idea before one of the clever ones. That does not mean we should encourage the stupid monkeys to believe the system is against them and they might be a misunderstood genius, because it would be vastly more productive to just encourage them to become a more intelligent monkey who studies hard. The other monkeys will listen to them, if they have something interesting to say.

Cosmology's Only Big Problems Are Manufactured Misunderstandings

If you keep up with the latest science news, you're probably familiar with a large number of controversies concerning the nature of the Universe itself. Dark matter, thought to outweigh normal atomic matter by a 5-to-1 ratio, could be unnecessary, and replaced by a modification to our law of gravity.