|Fig 1 from Harvey et al sketching how they estimated |
the position and trajectory of the Dark Matter.
- Harvey et al. "The nongravitational interactions of dark matter in colliding galaxy clusters" which observed 72 galaxy cluster collisions to compare the resulting centres of mass for the gas and stars (from direct observations) and for the dark matter (by inference). Based on these offsets, dark matter is clearly present and some models of dark matter can be excluded.
- Borsanyi et al. "Ab initio calculation of the neutron-proton mass difference" which calculates this (0.14%) from the fine-structure constant, thus reveals one aspect of how finely tuned our universe needs to be: if the mass difference were bigger or smaller, the world as we know it would probably not exist.
There are of course many important caveats. They don't have information about religious switching in China and there are reports of strong growth in Christianity in that great country. China has the majority of religiously un-affiliated people in the world so this would make a big difference. They assume that current patterns of falling away from faith will continue in the US and UK and other such places, and they do not allow for the possibility that people who fall away in their late teens and 20s may return later (as they are married with children for example). They also assume that almost no-one switches out from Islam based on extrapolating current trends where you can be murdered for doing so in many Muslim countries. This is, in another sense, indeed a dark matter.
But all of this really emphasises that, alongside a focus on evangelising the non-believer there needs to be a steady work on building up and confirming the faith of the believer. Our prayers and work need to be focused on both of these vital priorities in the UK. And we need to continue to pray for the growth of Christianity in China which will immeasurably strengthen that great country and the world as a whole.