Ergoregion instability of ultracompact astrophysical objects

Vitor Cardoso^*
Department of Physics and Astronomy, The University of Mississippi, University, Mississippi 38677-1848, USA

Paolo Pani^†
Dipartimento di Fisica, Università di Cagliari, Cittadella Universitaria 09042 Monserrato, Italy, and Department of Physics and Astronomy, The University of Mississippi, University, Mississippi 38677-1848, USA

Mariano Cadoni^‡
Dipartimento di Fisica, Università di Cagliari, and INFN sezione di Cagliari, Cittadella Universitaria 09042 Monserrato, Italy

Marco Cavaglià^§
Department of Physics and Astronomy, The University of Mississippi, University, Mississippi 38677-1848, USA

^*Presently at CENTRA, Department de Física, Instituto Superior Técnico, Avenida Rovisco Pais 1, 1049-001 Lisboa, Portugal.

vcardoso@phy.olemiss.edu

^†paolo.pani@ca.infn.it

^‡mariano.cadoni@ca.infn.it

^§cavaglia@phy.olemiss.edu