title: Entropy Inequality Violations from Ultraspinning Black Holes.
abstract: We construct a new class of rotating anti-de Sitter (AdS) black hole solutions with noncompact event horizons of finite area in any dimension and study their thermodynamics. In four dimensions these black holes are solutions to gauged supergravity. We find that their entropy exceeds the maximum implied from the conjectured reverse isoperimetric inequality, which states that for a given thermodynamic volume, the black hole entropy is maximized for Schwarzschild-AdS space. We use this result to suggest more stringent conditions under which this conjecture may hold.
authors.affiliation: Department of Physics and Astronomy, University of Waterloo, Waterloo, N2L 3G1 Ontario, Canada.
authors.forename: Robie A
authors.initials: RA
authors.lastname: Hennigar
authors.affiliation: Department of Physics and Astronomy, University of Waterloo, Waterloo, N2L 3G1 Ontario, Canada.
authors.forename: Robert B
authors.initials: RB
authors.lastname: Mann
authors.affiliation: Perimeter Institute, 31 Caroline St. N., Waterloo, N2L 2Y5 Ontario, Canada and Department of Physics and Astronomy, University of Waterloo, Waterloo, N2L 3G1 Ontario, Canada.
authors.forename: David
authors.initials: D
authors.lastname: Kubizňák