Journey to the Centre

Let's look at some different news from neutrino physics! Geologists have long dismissed convection models of geomagnetic field generation in favour of a fission reactor at the Earth's core. For instance, they point out that (i) the ratio of He3 to He4 in mantle fluids is $8$ times that of atmospheric concentrations and (ii) geomagnetic field variation is tricky to reconcile with convection models.

There is an estimated $12$ TW heat flow from the Earth's core. A core georeactor should generate a significant antineutrino flux. In March, the Borexino experiment rejected the hypothesis of a georeactor with a power greater than $3$ TW, with 95% confidence.

Alternative hypotheses include the KamLAND experiment's soliton nuclear georeactor (at $20$ TW), supposedly situated on the boundary between solid and liquid cores. Another hypothesis for field generation is fluid motion in a liquid iron core, and this is studied numerically, but one wonders how this theory can account for the mantle He3 abundance. Our favourite hypothesis, as you know, is Louise Riofrio's proposal of a black hole at Earth's core.