I read somewhere – I don’t think it was Kuhn himself, but someone analyzing Kuhn – that there came a point in the history of science where there was a divergence between scientists, with different scientists disagreeing about what counts as a theory, what counts as a test of a theory, what even counts as evidence. We have reached that point with the mass discrepancy problem.

This title is an example of what has come to be called Betteridge’s law. This is a relatively recent name for an old phenomenon: if a title is posed as a question, the answer is no . This is especially true in science, whether the authors are conscious of it or not. Pengfei Li completed his Ph.D. recently, fitting all manner of dark matter halos as well as the radial acceleration relation (RAR) to galaxies in the SPARC database.

This post is a recent conversation with David Garofalo for his blog. Today we talk to Dr. Stacy McGaugh, Chair of the Astronomy Department at Case Western Reserve University. David : Hi Stacy. You had set out to disprove MOND and instead found evidence to support it. That sounds like the poster child for how science works. Was praise forthcoming?

I have been busy teaching cosmology this semester. When I started on the faculty of the University of Maryland in 1998, there was no advanced course on the subject. This seemed like an obvious hole to fill, so I developed one.

Britain and America are two nations divided by a common language. attributed to George Bernard Shaw Physics and Astronomy are two fields divided by a common interest in how the universe works. There is a considerable amount of overlap between some sub-fields of these subjects, and practically none at all in others.

I haven’t written here since late January, which not coincidentally was early in the Spring semester. Let’s just say it was… eventful. Mostly in an administrative way, which is neither a good way, nor an interesting way. Not that plenty interesting hasn’t happened. I had a great visit to Aachen for the conference Dark Matter & Modified Gravity. Lots of emphasis on the philosophy of science, as well as history and sociology.

There is a tendency when teaching science to oversimplify its history for the sake of getting on with the science.

In the last post, I noted some of the sociological overtones underpinning attitudes about dark matter and modified gravity theories. I didn’t get as far as the more scientifically  interesting part, which  illustrates a common form of reasoning in physics. About modified gravity theories, Bertone & Tait state Leaving aside just which observations need to be mimicked so precisely (I expect they mean power spectrum;

A colleague points out to me a recent preprint by Bertone & Tait titled A New Era in the Quest for Dark Matter . Most of the narrative is a conventionalist response to the failure of experimental dark matter searches, posing a legitimate question in this context. Where do we take it from here?

Virginia, your little friends are wrong. They have been affected by the skepticism of a skeptical age. They do not believe except they see. They think that nothing can be which is not comprehensible by their little minds. All minds, Virginia, whether they be men’s or children’s, are little.