Research interests

  • Detecting and Interpreting Gravitational Waves from Compact binary mergers
  • Observational Tests of General Relativity
  • Integrability and Inverse Scattering
  • Numerical Relativity and black hole mergers
  • Continuous Gravitational Waves
  • Mathematical General Relativity
  • Black Holes and quasi-local horizons

Badri Krishnan

badri.krishnan at ru.nl

IMAPP
Radboud University
Heyendaalseweg 135
Nijmegen, Netherlands

badri.krishnan at aei.mpg.de

Albert Einstein Institute
Callinstr. 38
Hannover, Germany

Google Scholar
Spires
ORCID

The Strong Gravity Group in Nijmegen

  • Beatrice Bonga
  • Daniel Pook-Kolb
Graduate Students
  • Ariadna Ribes-Metideri
  • Stamatis Vretinaris
Former Graduate Students

Awards

  • 2017 Bruno Rossi Prize of the American Astronomical Society (shared with the LIGO Scientific Collaboration)
  • 2017 Group Achievement Award of the Royal Astronomical Society (shared with the LIGO Scientific Collaboration)
  • 2017 Princess of Asturias Award (shared with the LIGO Scientific Collaboration)
  • 2016 Breakthrough Prize in Fundamental Physics (shared with the LIGO Scientific Collaboration)
  • 2016 Gruber Cosmology Prize (shared with the LIGO Scientific Collaboration)
  • 2005 Burgen Scholar of the Academia Europaea
  • 2000-2001 Braddock and Roberts Fellow of the Pennsylvania State University
  • 1999 Penn State Physics Department Teaching Award

Selected Publications

Complete List of Publications

Black Hole Ringdown
  • Statistical validation of the detection of a sub-dominant quasi-normal mode in GW190521, C.D. Capano, J.Abedi, S.Kastha, A.H.Nitz, J.Westerweck, M.Cabero, A.B.Nielsen, B.Krishnan arxiv
  • Observation of a multimode quasi-normal spectrum from a perturbed black hole, C.D.Capano, M.Cabero, J.Westerweck, J.Abedi, S.Kastha, A.H.Nitz, A.B.Nielsen, B.Krishnan arxiv
  • Quasinormal modes and their overtones at the common horizon in a binary black hole merger, P.Mourier, X.J.Forteza, D.Pook-Kolb, B.Krishnan, E.Schnetter, arxiv PRD
  • The next decade of black hole spectroscopy, M.Cabero, J.Westerweck, C.D.Capano, S.Kumar, A.B.Nielsen, B.Krishnan,, arxiv PRD
  • Detectability of the subdominant mode in a binary black hole ringdown, S.Bhagwat, M.Cabero, C.D.Capano, B.Krishnan, D.A.Brown, arxiv PRD
  • Black hole spectroscopy: testing general relativity through gravitational wave observations, O.Dreyer, B.Kelly, B.Krishnan, L.S.Finn, D.Garrison, and R.Lopez-Aleman, arxiv CQG
Compact Binary Mergers
  • Using gravitational waves to distinguish between neutron stars and black holes in compact binary mergers, S.Kastha, C.D.Capano, J.Westerweck, M.Cabero, B.Krishnan arxiv ApJ
  • Model systematics in time domain tests of binary black hole evolution, S.Kastha, C.D.Capano, J.Westerweck, M.Cabero, B.Krishnan, arxiv PRD
  • Stringent constraints on neutron-star radii from multimessenger observations and nuclear theory, C.Capano, I.Tews, S.Brown, B.Margalit, S.De, S.Kumar, D.A.Brown, B.Krishnan, S.Reddy, arxiv Nature Astron.
  • 1-OGC: The first open gravitational-wave catalog of binary mergers from analysis of public Advanced LIGO data, A.H.Nitz, C.Capano, A.B.Nielsen, S.Reyes, R.White, D.A.Brown, B.Krishnan, arxiv ApJ
  • Low significance of evidence for black hole echoes in gravitational wave data, J.Westerweck, A.B.Nielsen, O.Fischer-Birnholtz, M.Cabero, C.D.Capano, T.Dent, B.Krishnan, G.Meadors, A.H.Nitz, arxiv PRD
  • Reducing the number of templates for aligned-spin compact binary coalescence gravitational wave searches using metric-agnostic template nudging, N.Indik, H.Fehrmann, F.Harke, B.Krishnan, A.B.Nielsen, arxiv PRD
  • Observational tests of the black hole area increase law, M.Cabero, C.D.Capano, O.Fischer-Birnholtz, B.Krishnan, A.B.Nielsen, A.H.Nitz, arxiv PRD
  • Stochastic template bank for gravitational wave searches for precessing neutron-star–black-hole coalescence events, N.Indik, K.Haris, T.Dal Canton, H.Fehrmann, B.Krishnan, A.Lundgren, A.B.Nielsen, A.Pai, arxiv PRD
  • GW150914: First results from the search for binary black hole coalescence with Advanced LIGO, B.P.Abbott et al (LIGO and Virgo Scientific Collaborations) arxiv PRD
  • Observation of Gravitational Waves from a Binary Black Hole Merger, B.P.Abbott et al (LIGO and Virgo Scientific Collaborations) arxiv PRL
  • The PyCBC search for gravitational waves from compact binary coalescence, S.A.Usman et al, arxiv CQG
  • Implementing a search for aligned-spin neutron star -- black hole systems with advanced ground based gravitational wave detectors, T. Dal Canton, A.H. Nitz, A.P. Lundgren, A.B. Nielsen, D.A. Brown, T. Dent, I.W. Harry, B. Krishnan, A.J. Miller, K. Wiesner, K. Wette, J.L. Willis, arxiv PRD
Mathematical Theory of Black Hole Horizons
  • Quasi-local black hole horizons, B.Krishnan (Handbook of spacetime}, Ch. 25, pages 527-555, Eds. A.Ashtekar and V.Petkov, Springer (June 2013)).
  • The spacetime in the neighborhood of a general isolated black hole, B. Krishnan arxiv CQG
  • Fundamental properties and applications of quasi-local black hole horizons, B. Krishnan arxiv CQG
  • Non-symmetric trapped surfaces in the Schwarzschild and Vaidya spacetimes, E.Schnetter and B.Krishnan arxiv PRD
  • On the existence of initial data containing isolated black holes, S.Dain, J.L.Jaramillo and B.Krishnan arxiv PRD
  • Isolated and dynamical horizons and their properties, A.Ashtekar and B.Krishnan arxiv Living Reviews
  • Dynamical horizons and their properties, A.Ashtekar and B.Krishnan arxiv PRD
  • Dynamical horizons: Energy, angular momentum, fluxes and balance laws, A.Ashtekar and B.Krishnan arxiv PRL
  • Distorted black holes with charge, S.Fairhurst and B.Krishnan arxiv IJMP
  • Generic isolated horizons and their applications, A.Ashtekar, C.Beetle, O.Dreyer, S.Fairhurst, B.Krishnan, J.Lewandowski, and J.Wisniewski, arxiv PRL
  • Isolated horizons: Hamiltonian evolution and the first law, A.Ashtekar, S.Fairhurst, B.Krishnan, arxiv PRD
Black Hole Mergers - Numerical Simulations
  • Tidal deformation of dynamical horizons in binary black hole mergers, V.Prasad, A.Gupta, S.Bose, B.Krishnan arxiv PRD
  • News from horizons in binary black hole mergers, V.Prasad, A.Gupta, S.Bose, B.Krishnan, E.Schnetter arxiv PRL
  • Horizons in a binary black hole merger II: Fluxes, multipole moments and stability, D.Pook-Kolb, O.Birnholtz, J.L.Jaramillo, B.Krishnan, E.Schnetter arxiv
  • Horizons in a binary black hole merger I: Geometry and Area Increase, D.Pook-Kolb, O.Birnholtz, J.L.Jaramillo, B.Krishnan, E.Schnetter arxiv
  • Self-intersecting marginally outer trapped surfaces, D.Pook-Kolb, O.Birnholtz, B.Krishnan, E.Schnetter arxiv PRD
  • The interior of a binary black hole merger, D.Pook-Kolb, O.Birnholtz, B.Krishnan, E.Schnetter arxiv PRL
  • The existence and stability of marginally trapped surfaces, D.Pook-Kolb, O.Birnholtz, B.Krishnan, E.Schnetter arxiv PRD
  • Dynamics of marginally trapped surfaces in a binary black hole merger: Growth and approach to equilibrium, A.Gupta, B.Krishnan, A.B.Nielsen, E.Schnetter, arxiv PRD
  • Quasi-local linear momentum in black-hole binaries, B.Krishnan, C.Lousto, and Y.Zlochower arxiv PRD
  • Spin Flips and Precession in Black-Hole-Binary Mergers M.Campanelli, C.Lousto, Y.Zlochower, B.Krishnan, and D.Merritt, arxiv PRD
  • Introduction to dynamical horizons in numerical relativity, E.Schnetter, B.Krishnan, and F.Beyer arxiv PRD
  • Introduction to isolated horizons in numerical relativity, O.Dreyer, B.Krishnan, D.Shoemaker, and E.Schnetter arxiv PRD
Continuous Gravitational Waves
  • Search for Continuous Gravitational Waves from Scorpius X-1 in LIGO O2 Data Y.Zhang, M.A.Papa, B,Krishnan, A.L.Watts arxiv ApJ Lett
  • Resampling to accelerate cross-correlation searches for continuous gravitational waves from binary systems G.D.Meadors, B.Krishnan, M.A.Papa, J.T.Whelan, Y.Zhang, arxiv PRD
  • Optimally setting up directed searches for continuous gravitational waves in Advanced LIGO O1 data, J.Ming, M.A.Papa, B.Krishnan, R.Prix, C.Beer, S.J.Zhu, H-B.Eggenstein, O.Bock, B.Machenschalk arxiv PRD
  • An Einstein@home search for continuous gravitational waves from Cassiopeia A, S.J.Zhu, M.A.Papa, H-B.Eggenstein, R.Prix, K.Wette, B,Allen, O.Bock, D.Keitel, B.Krishnan, B.Machenschalk, M.Shaltev, X.Siemens, arxiv PRD
  • Upper limits on gravitational waves from Scorpius X-1 from a model-based cross-correlation search in Advanced LIGO data, J.Aasi et al (LIGO and Virgo Scientific Collaborations), D.Steeghs and L.Wang arxiv ApJ
  • Optimal directed searches for continuous gravitational waves, J.Ming, B.Krishnan, M.A.Papa, C.Aulbert, H.Fehrmann, arxiv PRD
  • Application of a Hough search for continuous gravitational waves on data from the fifth LIGO science run, J.Aasi et al (LIGO and Virgo Scientific Collaborations) arxiv CQG
  • Einstein@Home All-sky Search for Periodic Gravitational Waves in LIGO S5 Data, J.Aasi et al (LIGO and Virgo Scientific Collaborations) arxiv PRD
  • Gravitational waves from neutron stars: Promises and challenges, N.Andersson, V.Ferrari, D.I.Jones, K.D.Kokkotas, B.Krishnan, J.Read, L.Rezzolla, B.Zink, arxiv GRG
  • Targeted search for continuous gravitational waves: Bayesian versus maximum-likelihood statistics, R.Prix and B.Krishnan arxiv CQG
  • Detecting gravitational wave emission from the known accreting neutron stars, A.L.Watts, B.Krishnan, L.Bildsten, and B.F.Schutz, arxiv MNRAS
  • All-sky Search for Periodic Gravitational Waves in LIGO S4 Data, B.Abbott et al (LIGO Scientific Collaboration) arxiv PRD
  • The cross-correlation search for periodic gravitational waves, S.Dhurandhar, B.Krishnan, H.Mukhopadhyay, and J.T.Whelan, arxiv PRD
  • Improved Hough search for gravitational wave pulsars, A.Sintes and B.Krishnan arxiv JPCS
  • Wide parameter search for isolated pulsars using the Hough transform, B.Krishnan arxiv CQG
  • Improved stack-slide searches for gravitational-wave pulsars, C.Cutler, I.Gholami, B.Krishnan arxiv PRD
  • First all-sky upper limits from LIGO on the strength of periodic gravitational waves using the Hough transform, B.Abbott et al (LIGO Scientific Collaboration) arxiv PRD
  • The Hough transform search for continuous gravitational waves, B.Krishnan, A.M.Sintes, M.A.Papa, B.F.Schutz, S.Frasca, and C.Palomba, arxiv PRD
Waveform Modeling
  • Airy-function approach to binary black hole merger waveforms: The fold-caustic diffraction model, J.L.Jaramillo, B.Krishnan arxiv
  • Testing gravitational waveform models using angular momentum, N.Khera, A.Ashtekar, B.Krishnan arxiv PRD
  • Matching post-Newtonian and numerical relativity waveforms: systematic errors and a new phenomenological model for non-precessing black hole binaries, L.Santamaria, F.Ohme, P.Ajith, B.Bruegmann, N.Dorband, M.Hannam, S.Husa, P.Moesta, D.Pollney, C.Reisswig, J.Seiler, and B.Krishnan, arxiv PRD
  • Phenomenological template family for black-hole coalescence waveforms, P.Ajith, S.Babak, Y.Chen, M.Hewitson, B.Krishnan, J.T.Whelan, B.Brugmann, P.Diener, J.Gonzalez, M.Hannam, S.Husa, M.Koppitz, D.Pollney, L.Rezzolla, L.Santamaria, A.M.Sintes, U.Sperhake, and J.Thornburg, arxiv CQG
  • A Template bank for gravitational waveforms from coalescing binary black holes. I. Non-spinning binaries, P.Ajith, S.Babak, Y.Chen, M.Hewitson, B.Krishnan, J.T.Whelan, B.Brugmann, P.Diener, J.Gonzalez, M.Hannam, S.Husa, M.Koppitz, D.Pollney, L.Rezzolla, L.Santamaria, A.M.Sintes, U.Sperhake, and J.Thornburg, arxiv PRD

Teaching

The Gravity+ Synergy Track at Radboud University

Selected Summer School Lectures
Plain Academic