Physics in a diverse world…

Regular observers of the arXiv will have noticed a recent deluge avalanche of papers from the recent Snowmass Community Planning Exercise. There are many excellent reports although they came out all in a flurry which has made it difficult to keep on top of them.

An example that I missed was one that appeared in the Physics Education section of arXiv that arose from a talk by theoretical physicist Howard Georgi given at the KITP Conference: Snowmass Theory Frontier on Feb. 23, 2022. The paper, entitled Physics in a diverse world or A Spherical Cow* Model of Physics Talent, doesn’t have an abstract but is quite short and is well worth reading. You can download it here.

Here is a short extract with which I agree fully the philosophy of which I have tried very hard to follow ever since I got my first Professorship in 1998 (though not always with the cooperation of all colleagues, and sometimes, in the past, against the opposition of a few):

If your career is established and you are not making an explicit and continual effort to encourage, mentor, and support all young physicists, to create a welcoming climate in your department, and to promote the hiring of diverse faculty members, you are part of the problem.

I’m hoping next week to be able to pass on some exciting news in this regard about Maynooth University.

I wrote some of my own thoughts from the point of view of LGBT+ diversity here but much of what I said in that context is of wider relevance.

But that brings us to the question of why we should care about whether LGBT students might be deterred from becoming scientists. This is much the same issue as to why we should worry that there are so few female physics students. The obvious answer is based on notions of fairness: we should do everything we can to ensure that people have equal opportunity to advance their career in whatever direction appeals to them. But I’m painfully aware that there are some people for whom arguments based on fairness simply don’t wash. For them there’s another argument that may work better. As scientists whose goal is – or should be – the advancement of knowledge, the message is that we should strive as hard as possible to recruit the brightest and most creative brains into our subject. That means ensuring that the pool from which we recruit is as large and as diverse as possible. The best student drawn from such a pool is likely to be better than the best student from a smaller and more restricted one.

Big companies haven’t become gay-friendly employers in recent years out of a sudden urge for altruism. They’ve done it because they know that they’d otherwise be discouraging many excellent potential employees from joining them. It’s exactly the same for research

*This is an allusion to the old joke for the tendency of scientists – especially theoretical physicists – to adopt highly simplified models of complex phenomena.

3 Responses to “Physics in a diverse world…”

In this paper we will list a few important goals that need to be addressed in the next decade, also taking into account the current discordances between the different cosmological probes, such as the disagreement in the value of the Hubble constant $H_0$, the $\sigma_8$–$S_8$ tension, and other less statistically significant anomalies. While these discordances can still be in part the result of systematic errors, their persistence after several years of accurate analysis strongly hints at cracks in the standard cosmological scenario and the necessity for new physics or generalisations beyond the standard model. In this paper, we focus on the $5.0\,\sigma$ tension between the {\it Planck} CMB estimate of the Hubble constant $H_0$ and the SH0ES collaboration measurements. After showing the $H_0$ evaluations made from different teams using different methods and geometric calibrations, we list a few interesting new physics models that could alleviate this tension and discuss how the next decade’s experiments will be crucial. Moreover, we focus on the tension of the {\it Planck} CMB data with weak lensing measurements and redshift surveys, about the value of the matter energy density $\Omega_m$, and the amplitude or rate of the growth of structure ($\sigma_8,f\sigma_8$). We list a few interesting models proposed for alleviating this tension, and we discuss the importance of trying to fit a full array of data with a single model and not just one parameter at a time. Additionally, we present a wide range of other less discussed anomalies at a statistical significance level lower than the $H_0$–$S_8$ tensions which may also constitute hints towards new physics, and we discuss possible generic theoretical approaches that can collectively explain the non-standard nature of these signals.