Fritz Zwicky is often credited for coining the term 'dark matter' but that's not quite true: the term had been in use for *decades* when he published his famous 1933 paper, and he was well aware of that. A #Thread on the early history of #darkmatter

https://twitter.com/Perimeter/status/963777205468909568?s=20

A few months before publishing the 1933 paper, in an article on cosmic rays, Zwicky wrote in passing "according to the present estimates, the average density of dark matter in our galaxy and throughout the rest of the universe are in the ratio 100000"😯journals.aps.org/pr/pdf/10.1103…

The statement that 95% of the Universe is "dark" or "unknown" can be quite misleading if not properly qualified. It actually applies only at very large length scales (way beyond the largest structures in the Universe), and at a specific time (now) 1/5 In the local Universe things are different: in a sphere centered around the Sun and radius equal to the Earth's orbit, the Universe is ~100% ordinary matter. In a sphere surrounding our Galaxy, the dominant component is dark matter, while dark energy is irrelevant👇2/5

The @NobelPrize to Jim Peebles represents, among other things, the first Nobel prize for the discovery of Dark Matter. Here are some thoughts, also based on discussions with him about the evidence for DM, and his own role in the discovery. THREAD First, to clear any confusion: the observational discovery of the accelerated expansion of the universe (often referred to as the Dark Energy problem) had already celebrated with the prize awarded in 2011 nobelprize.org/prizes/physics…

Don't fall for this sensationalist nonsense. No, funding agencies are NOT "pouring money” into "any proposed experiment that could plausibly be said to maybe detect something”. Anyone who knows anything about dark matter searches can confirm

https://twitter.com/skdh/status/1140962504333516800

The article misleads readers into thinking that experiment *proposals*, put together with pen and paper and in some cases virtually unknown in the community, are all actual "few million dollars" experiments.

Ironic to see today's spectacular results from @ehtelescope summarized as "Einstein was right". Einstein did NOT believe black holes could exist. Here's his 1939 article about "Schwarzschild singularities" (term 'black hole' was coined much later by J. Wheeler) See the full article at jstor.org/stable/1968902

Will the next Einstein be a machine? A number of recent studies show this scenario may not be that implausible after all (thread) In "Discovering physical concepts with neural networks” @eth researchers presented a neural network architecture that can discover physical concepts from experimental data without being provided with additional prior knowledge

Who discovered dark matter in galaxies? Here’s a thread based on our “A history of dark matter” (see arxiv.org/abs/1605.04909 for details and all references) In the 1960s radio astronomers measured the rotation curve of the Andromeda galaxy, out to a relatively large radius. See the data obtained by Mort Roberts in 1966