About me

This is Néstor Ortiz. I am a researcher at the Institute for Nuclear Science (ICN) of the National Autonomous University of Mexico (UNAM). My research focuses on the strong-field regime of classical gravity, either in the context of Einstein’s General Relativity, or alternative theories. I am interested in fundamental aspects of gravity, as well as in applications to high-energy astrophysics.

Research

Gamma radiation from neutron stars in binary systems

Using numerical simulations, we predict the gamma-ray emission pattern from a black hole - neutron star binary just a moment before merger. We find that face-on observers receive little emission, equatorial observers see one broad peak, and more generic observers typically see two peaks.

Crust meltdown in binary neutron stars

We show that, through resonant tidal excitations in a binary inspiral, neutron star crusts generically undergo elastic-to-plastic transition, which leads to crust heating and eventual meltdown.

Fixing extensions to General Relativity in the nonlinear regime

Inspired in the approach to 'fixing' viscous relativistic hydrodynamics by Israel and Stewart, we introduce a strategy to evade the ill posedness of certain Cauchy problems. We sketch the implementation of this idea in a couple of effective theories of gravity.

Shadow of a naked singularity

We analyze the redshift suffered by photons originating from an external source, traversing a collapsing dust cloud, and finally received by an asymptotic observer. We then study the shadow that the collapsing cloud casts on the sky of the asymptotic observer.

Contact Me

nestor.ortiz[at]nucleares.unam.mx
Office phone: 555 622 4660 Ext. 3313

Instituto de Ciencias Nucleares, UNAM
Circuito Exterior C.U., A.P. 70-543,
04510, Cuidad de México, México.
Office F-305.