Chiamaka has shown that you can use the simple idea of energy conservation, combined with knowing when an ellipsoid collapses, to predict how dense (and hot) a dark matter halo will be when it forms. Previously, people had to rely on numerical simulations, and ad hoc extrapolations and fitting functions, which often led to contradictory conclusions for the densest dark matter haloes. However, her method is more robust, easy to use, and elegant (and I am in no way biased 🙂 ) ! You can also apply it to any cosmology or initial conditions.
This weekend at Mann Fest, we celebrated the contributions of our colleague Robb Mann, on the occasion of his 60th birthday. Robb is very prolific, both in producing innovative scientific research, but also in training excellent undergraduate and graduate students. I met several of them during Mann Fest, who have now scattered across the globe, many as successful professors, and are engaged in diverse and exciting research. Not surprisingly, Robb is also an extraordinary lecturer.
Einstein’s General theory of Relativity predicts the occasions of its own demise. These are known as spacetime singularities, where Einstein’s equations fail to predict the future. However, in most typical situations, we have found that the singularities lie behind event horizons of black holes. Since nothing moves faster than speed of light in Relativity, and light cannot escape event horizons, then it appears that most common singularities are invisible to us. Penrose promoted this observation to the Cosmic Censorship conjecture, proposing that singularities are generically censored by event horizons, to outside observers.
Congratulations to Dr. Farbod Kamiab@fkamiab on successful defence of his PhD dissertation: “Neutron Stars, the Exotica: From Modifying General Relativity to Strong Magnetic Fields”. He is now the world expert in the most exotic things that could happen to the most exotic stars in our universe!
Here is a quick run through his final presentation: