A Blog About the Science and Sociology of Cosmology and Dark Matter
It is straightforward to falsify theories that make clear predictions, should they happen to be wrong. It is impossible to falsify ideas that involve invisible components. Specific theories of dark matter (e.g., WIMPs) can be seen to be increasingly unlikely, but can they be falsified outright? If we decide that WIMPs have been practically falsified … Continue reading The contradiction in our dark…
A few posts back, the issue of the Bullet Cluster came up in the comments. I was still working my way up to addressing that in a full post, so I limited myself to making a sociological observation based on my experience: People who invoke the bullet cluster in response to queries about MOND are … Continue reading The blinding influence of the Bullet Cluster →
In the last few posts we’ve discussed the local missing baryon problem in extragalactic objects spanning over ten orders of magnitude in mass from tiny dwarfs to rich clusters of galaxies. This discussion has so far been entirely in the context of LCDM. So – how does LCDM compare with MOND? As a refresher, these … Continue reading Missing baryons: LCDM and MOND compared →
Our cosmology du jour, LCDM, suffers a local missing baryon problem: we don’t detect all of the baryons we expected to find associated with the dark matter halos of individual galaxies. Should we? Empirically, yes. The stars and cold (atomic and molecular) gas appear to be all that there is to see in late type … Continue reading Local baryons in simulations and reality →
Last time, we started talking about the data in the recent paper The Baryonic Mass-Halo Mass Relation of Extragalactic Systems. Here, we’ll put on our dark matter hat, and use the data to make an accounting of the mass – both the dark matter and the baryons in all their various forms. From this conventional … Continue reading The local missing baryon problem →
Previously I had alluded to some of the major projects I’ve been working on. One has come to fruition and can be found on the arXiv and in the Astrophysical Journal&. It has taken many years to assemble the data in this paper, during which time the models purporting to explain some of it have … Continue reading Extended Tully-Fisher relations →
I have been concerned for years that dark matter was morphing from legitimate science into a cold, dark religion. I have been reluctant to put it that way, because there are lots of scientists who work on dark matter that have not fallen entirely down that rabbit hole and who continue to make valuable contributions … Continue reading Yep, it’s a religion →
AP News recently ran a story on the interface of religious inspiration and the search for dark matter. I thought about commenting on it, then thought better of it, but now here I am again. I know some but not all of the people who are quoted, all good scientists. The article ends with a … Continue reading The well of inspiration →
I see that I’ve been posting once a month so far in 2026. I’ve lots to say but no time to say it. Some of it good, some of it bad, maybe sometime I’ll get around to it. No guarantees. On the good side, I’ve been working on a big project or two; may have … Continue reading Paradigm Shifts in Modern Astrophysics →
There are more things in heaven and earth, Horatio, than are dreamt of in your philosophy. – Hamlet One of the great privileges of astronomy is that there’s always something new and surprising to discover. It’s a big universe. There’s a lot in it. In appreciation of this simple joy, I thought I’d share a … Continue reading Asteroids that spin really fast →