Oddbean

You make some observations that existing theory can't explain So you invent a new concept to explain these observations This is a hypothesis Now you have to go do actual science and test your hypothesis You have to understand this thing you've postulated and explain it "Dark matter" as a stand-in for unobserved matter that is hypothesized to affect gravity is totally fine and scientific But it's not a theory or law of science or any such thing And treating it as a real, known entity on par with regular matter is in fact deeply unscientific

Our knowledge of atoms started as spherical marbles. You're nitpicking over the fact if something is an hypothesis, a model, a theory ot a law. I'm not that interested in those sorts of semantic discussions since they are fairly subjective and contextual. Physics most of the time moved forward by people "making stuff up" to fill unexplained observations. I can take your argument and extend it to neutrinos shortly after they were discovered. By your logic, equating them to "real" matter does not make sense.

The neutrino particle was never hypothetical. It was made up to explain an observation. Half a century later that hasn't changed. The Higgs Boson was hypotetical. When proposed, it did not explain any measurement at the time.

"The neutrino particle was never hypothetical. It was made up to explain an observation." From wiki: "A hypothesis (pl.: hypotheses) is a proposed explanation for a phenomenon. For a hypothesis to be a scientific hypothesis, the scientific method requires that one can test it." Something made up to explain observations is literally the definition of a hypothesis.

You're correct. When I said "hypothetical", I really meant "speculative" or "conjectural". That definition of hypothetical is a bit broad, but ok, I'll take it. With that definition, every scientific model is hypothetical since it is proposed and requires continuous testing and validation. Nothing remains proven forever. Back to the original example: dark energy is a "hypothetical" scientific model, not conjectural. We are not waiting or looking to observe it, we already did measure it. It's a simplist shallow model, but the best one so far.

How independent is galaxy redshift from whatever phenomena produced the dark energy theory in the first place? Based on the wiki for Dark Energy, DE was theorized to explain supernova redshift In which case I am very skeptical that further redshift observations confirm anything positive about the nature of DE as an explanatory factor

DE is an integral part of the Standard Cosmology Model as a whole, without it it would fall apart. The LCDM together with the Friedman equations, explain most expansion measurements fairly well. https://en.m.wikipedia.org/wiki/Lambda-CDM_model

The hypothesis is tested, ideally many times by many people In each case, the test produces results consistent with the hypothesis These tests form a body of evidence that serves to disprove competing hypotheses and (until some sort of contradictory evidence is found) makes the theory well-established So you observe something, then you form a hypothesis to explain the observation, but that's not enough to be scientific. You have to actually test the hypothesis and try to explain what's happening. Merely positing a hypothesis is not good enough. A hypothesis which serves to "explain" without producing understanding is also not good enough. In creationism / intelligent design debates there's a notion of "god of the gaps" where god is invoked to fill in a gap in knowledge, which doesn't really explain anything so much as give a label to our ignorance. The same thing happens in physics where some particle or phenomenon is posited to "explain" observations that are inconvenient / inconsistent with existing theory. Unless those hypothetical particles / phenomena can be tested and their mechanisms understood, they are just other ways of naming our ignorance.

I like your argument here but the "something that produces understanding" part is fairly subjective and fragile. Ofc I know what you mean there and don't mean to gaslight but it's still not a solid definition.