by Richard E. | May 17, 2023 | Dark matter and dark energy, Self Gravitating Quantum Matter
Ultralight dark matter halos have central solitons and the soliton mass is correlated with the overall halo mass. However, the exact form of the “core-halo” relation that sets the ratio of these masses is not well understood. However, realistic halos will...
by Richard E. | Feb 11, 2023 | Early universe dynamics and observables
Many efforts to constrain cosmological models focus on measurements of the spectral index and tensor amplitude. However, the tensor amplitude could be vanishingly small in which case the scale dependence of the spectrum, or the running, may actually be more accessible...
by Richard E. | Dec 22, 2022 | Black Holes and Gravitational Waves, Primordial nonlinearity, Self Gravitating Quantum Matter
If they do not thermalise quickly, generic inflationary models with become highly inhomogeneous if there is a long matter-dominated phase following the end of inflation. We compute the gravitational wave signal generated by the simplest models. We show that with...
by Richard E. | Dec 12, 2022 | Dark matter and dark energy, Self Gravitating Quantum Matter
Ultralight dark matter halos have central “solitons” – compact, overdense regions where the ultralight dark matter is supported by “quantum pressure”. Simple ULDM models suggest that there is a relationship between the mass of the halo and the...
by Richard E. | May 3, 2022 | Writing and Videos
Richard’s appearance on Tim Nguyen’s Cartesian Cafe podcast – this gets technical in parts, but covers ideas from theories of everything through to the basics of the expanding universe…
