The Lazarus Project
Intensive efforts have been underway in the past decade to write
numerical codes able to solve Einstein's system of ten coupled
non-linear partial differential equations, on powerful supercomputers;
so far the numerical treatment of black hole systems in full 3D has
proved very difficult. Motivated by the desire to provide expectant
gravitational-wave observers with some estimate of the full merger
waveforms, and to prepare the arena for future, more advanced
numerical simulations, we have recently pursued a hybrid approach to
the problem, called the Lazarus project.
The underlying idea of Lazarus is very simple (see Figure): apply the
far-limit (FL), full-numerical (FN) and close-limit (CL) treatments in
sequence. In this way we can restrict the finite time interval of full
non-linear numerical evolution to covering the stage of the dynamics
where no perturbative approach is applicable, and still derive the
complete black hole ring-down and the propagation of radiation into
the wave zone with a close limit perturbative treatment. The
perturbative model not only allows an inexpensive and stable
continuation of the evolution (which is then allowed to rise and live
again like the biblical Lazarus), but also supplies a clear
interpretation of the dynamics not manifest in the generic numerical
We have successfully addressed the problem of combining the
close-limit approximation describing ringing black holes and full
numerical relativity, required for essentially nonlinear interactions,
producing the first calculation of complete plunge waveforms, total
gravitational energy, angular momentum radiated from the coalescence
of two black holes from an estimate of the innermost stable circular
orbit down to the final single rotating black hole.
Our work has been featured in the "News and Views" section of Nature (see the picture
story ). Our latest results were used in a groundbreaking
article in Science to improve an astrophysical model on radio-jet
evidence for supermassive black holes.
Our next goal is to refine our approach, and working together with
several colleagues in the numerical relativity group, to extend the
duration of the numerical simulations to permit studies of more
separated black hole configurations. The reason is that we would like
to build a connection to more astrophysically realistic initial data
descriptions such as with a true interface to the post-Newtonian
We are also particularly interested in using the machinery of the
Lazarus project as a tool to improve detection strategies for black
hole collision waveforms (the Kudu
project). The first step will be to explore the dependence of the
waveforms on the astrophysical parameters, such as mass ratios and
spin magnitudes and orientation, for black-hole binary systems.
We are working on extending Lazarus by using the quasi-Kinnersley
tetrad. The resulting Lazarus 2 will be more
robust than original Lazarus.
Waves from Black Hole Collisions via an Eclectic Approach
J. Baker, B. Brügmann, M. Campanelli, and C. O. Lousto;
Class. Quantum Grav. 17 (2000) L149-L156
Original paper: Plunge
Waveforms from Inspiralling Binary Black Holes
J. Baker, B. Brügmann, M. Campanelli, C. O. Lousto, and
Phys. Rev. Lett. 87 (2001) 121103
Detailed Theory Paper: "The Lazarus
project: A pragmatic approach to binary black hole evolution"
J. Baker, M. Campanelli, and C. O. Lousto
Phys. Rev. D 65 (2002) 044001
Main Results Paper: "Modeling
gravitational radiation from coalescing binary black holes"
J. Baker, M. Campanelli, C. O. Lousto, and R. Takahashi
Phys. Rev. D 65 (2002) 124012
Coalescence remnant of spinning binary black holes
J. Baker, M. Campanelli, C. O. Lousto, and R. Takahashi
Phys. Rev. D 69 (2004) 027505
Lazarus2 paper: "The Lazarus project. II. Space-like extraction with the quasi-Kinnersley tetrad"
M. Campanelli, B. J. Kelly, and C. O. Lousto
Phys. Rev. D 73 (2006) 064005
"Lazarus2: Applying the quasi-Kinnersley Frame in the Lazarus Project" -- talk by Bernard Kelly, Penn State Sources & Simulations Seminar September 29, 2005
Meeting Transparencies by Manuela Campanelli, LIGO Livingston Observatory,
Livingston, Louisiana March 20-23, 2002
See also the Feichtbereit
Talk by Manuela Campanelli, AEI September 2001.
See also the Numerical
Relativity and Black Hole Collisions at the 20th Texas Symposium on
Relativistic Astrophysics by Pablo Laguna, February 2001.
Catalog: Black Hole Ringdown Sources AstroGravS: Astrophysical Gravitational-Wave
Source Archive at the Laboratory for
High Energy Astrophysics, NASA Goddard.
"Black hole mergers: from simulation to detection" Invited Talk given
by Manuela Campanelli at the LSC Workshop 3/20/2002. (PPT,
"An Eclectic Approach to Binary Black Hole Collisions" Talk at ITP
(Trieste) by John Baker June 2000.
Images and Movies
Lazarus Project: Numerical relativity meets perturbation theory by
Richard Price, Matters Of Gravity: The Newsletter Of The APS Topical Group
On Gravitation. Vol.19,
ISSN pp 1527-3431 (Feb. 2002).
See also the
Wave Source Simulation program at Caltech (topic
Visualize Waves in Space Caused by Mergers of Black Holes" Pennsylvania
State University News Release, July 24, 2002.
model waves caused by black hole mergers" "SpaceFlight Now
Breaking News", July 25, 2002.
Visualize Waves In Space Caused By Mergers Of Black Holes"Space
Daily, Your Portal to Space, July 26, 2002.
Holes collide in computer by Will Knight, NewScientist.com's news service,
July 26, 2002.
holes take the plunge" by Bernard Schutz (Max Planck Society for
the Advancement of Science, Press and Public Relations Department,
September 13, 2001)
holes take the plunge" Cosmiverse Space News, September 14, 2001
Simulations Predict What Astronomers Will See With Gravitational Wave Telescopes
When Two Black Holes Collide" by Editor (Science
Daily, September 19, 2001)
Loecher "Lazarus"-Team simuliert Kollision" by the Editor of (Astronews,
September 20, 2001)
aus der Urzeit des Weltalls" by Von Ina Helms (Berliner
Morgenpost, September 20, 2001)
physics: Black hole blockbuster" by Sarah Tomlin (Nature,
[PDF] October 4, 2001)
erstmals sichtbar" by Bernard Schutz (National Geographic, November
Universum: Kollisionen, die im Raum Wellen schlagen" by Thomas Buerke
(MaxPlanckForshung Vol. 4[PDF#1,