Thursday, March 05, 2020

Hexaquark dark matter

Harvard politics: Warren would win among Harvard faculty and only 1.46% of faculty managed to be conservative. That places conservatives beneath transsexual Muslim vegans. Oops.

Thank God, blacks in the South were more conservative than demanded by the grassroot Democrats and Sleepy Joe won Super Tuesday and reduced the probability of a Great October Democratic Socialist Revolution (a standard euphemism for a communist coup in November). U.S. stocks reacted by a 5% rise although the attribution is never quite clear.
Dark matter seems to be there, its composition remains unclear. WIMPs, axions etc. are waiting to be directly detected. Science Alert published a press release
Physicists Think We Might Have a New, Exciting Dark Matter Candidate
Well, I would choose to say that it is a not quite new and a boring dark matter candidate. Protons and neutrons are created out of 3 quarks (3 is odd which is why they are fermions), mesons are made of quark-antiquark pairs (and they are therefore bosons). But exotic bound states with 4,5,6 (tetraquarks, pentaquarks, hexaquarks) have been proposed and somewhat uncertainly measured.

In 2014, a group measured something about the neutron-proton scattering. They found a resonance (or its lookalike) of mass 2.380 GeV and width 0.07 GeV. 3+3=6 and therefore the object would be a hexaquark. It's been identified with d*, a previously proposed hexaquark (pronounce "d-star"). The mass measurement allows us to call it d* (2380).

Now, in recent papers from the York University, Daniel P. Watts, Mikhail Bashkanov, and perhaps occasional collaborators propose this hexaquark as a dark matter candidate. More precisely, they claim that a Bose-Einstein condensate is made of it.

OK, I am not getting the invention that would deserve media coverage. What is the real evidence that these hexaquarks create primordial condensates? Surely a condensate is not a valid description at the above-the-QCD-scale temperatures in the first millisecond of the Universe. And why would the Bose-Einstein character matter at all? Why would it be invisible electromagnetically and gravitationally? What is the size of those objects, why, and how does it help to make the theory consistent with observations? How does it differ from neutron stars that are visible, not dark?

I am sure many of those questions may be answered by someone who is an actual expert in astrophysics, and some others, or they have some answers in those papers in some cases, but I still feel that the papers are more confused than I am. They seem to pick a random resonance and apply it in a random other place. That's how I feel about it. Which is why I find it natural that the paper has 0 followups after more than a month. Such papers may still be made very visible by press releases and the media in general which is why many people sent the news to me. Hmm, sorry, a classic distortion of attention created by the media.

Of course dark matter might be made out of hexaquarks of some type. Or something else. But I don't believe that they have found real solid evidence that this is a much more likely scenario than a random object from particle or nuclear physics that you make up – or at least they didn't present such evidence rationally. This is the culture of "I will invent some random meme and make a career out of it by marketing it vigorously", the kind of physics that I would associate with a notorious asset of Jeffrey Epstein's.

P.S.: Smart readers have found out more important problems with this dark matter claim than I did. In particular, the particle is a highly unstable resonance. Second, a particle equivalent to a proton+neutron is charged so one needs some electrons or something to neutralize the charge and the result won't be dark at all.

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