Geoffrey LovelaceGeoffrey Lovelace

Contact Information

Office
McCarthy Hall 601B

Email
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Mailing Address
Department of Physics, MH-611
California State University, Fullerton
800 North State College Blvd.
Fullerton, CA 92834
 
Phone 
+1 (657) 278-7501

LIGO Hanford
The LIGO interferometer in Hanford, Washington. (Photo courtesy LIGO Laboratory.)
 
 
 
Merging black holes
 

Merging black holesTop: Snapshot of two rapidly rotating black holes about to merge. The holes rotate around the shafts of the white arrows; also shown are the holes’ trajectories (pink, blue curves). Bottom: the emitted gravitational wave from this binary (green curve). (Images courtesy Robert McGehee, Jr.)

 

Black hole horizon

The common horizon enclosing the horizons of two rapidly rotating black holes just after they have merged.

 

Research

I am an assistant professor in the Department of Physics at California State University, Fullerton. My current research interests focus on using numerical relativity to model sources of gravitational waves, such as merging black holes. I join assistant professors Jocelyn Read and Joshua Smith in Cal State Fullerton's Gravitational Wave Physics and Astronomy Center (GWPAC), and I also am a member of the Simulating eXtreme Spacetimes (SXS) collaboration and the LIGO Scientific Collaboration

GWPAC and the SXS collaboration are contributing to LIGO's discovery of gravitational waves.

At Cal State Fullerton, my research goals focus on modeling sources of gravitational waves using numerical relativity. Gravitational waves—ripples of spacetime curvature—are opening a new window on the universe. The Advanced Laser Interferometer Gravitational-wave Observatory (Advanced LIGO) has observed the first (and second) gravitational waves passing through Earth, and both came from merging black holes. My students and I use supercomputers to simulate colliding black holes using the Spectral Einstein Code (SpEC), and we are particularly interested in binaries with high black-hole spins and in responding to LIGO observations. I recently have begun using supercomputers to model thermal noise in LIGO mirrors, with the goal of helping to improve the sensitivity of next-generation detectors.

As a graduate student at Caltech, my research spanned a variety of topics in gravitational-wave physics, including thermal noise in gravitational-wave detectors, black-hole tidal deformation, and reducing orbital eccentricity and spurious gravitational radiation in numerical simulations of binary black holes. Building on this broad introduction, I focused my postdoctoral research at Cornell entirely on numerical relativity: I have simulated merging black holes with the highest spins to date, explored new tools for building physical insight into strongly warped spacetime, and investigated implicit-explicit time stepping as a way to reduce the cost of binary black hole simulations.

 

Support

My students and I are pleased to thank the National Science Foundation, the Research Corporation for Science Advancement, the Louis Stokes Alliance for Minority ParticipationCalifornia State University, Fullerton, and Cal State Fullerton alumnus Dan Black. Our research is supported in part by the following external grants:

NSF grant PHY-1654359CAREER: Computational Gravitational-Wave Science and Education in the Era of First Observations.

NSF grant PHY-1606522. RUI: Computational Gravitational-Wave Research for the Era of First Observations.

NSF grant AST-1559694. The CSUF-Syracuse partnership for inclusion of underrepresented groups in gravitational-wave astronomy.

NSF grant PHY-1429873. MRI: Acquisition of a High-Performance Computer Cluster for Gravitational-Wave Astronomy with Advanced LIGO.

Our work has also been supported in the past by the following external grants:

Multi-investigator Cottrell College Science Award. Developing a numerical injection analysis pipeline for gravitational waves from merging black holes and neutron stars.

NSF grant PHY-1307489. RUI: Numerical Simulations of Merging Black Holes and Neutron Stars.

 

 


 

Teaching

I have taught the following courses:

Physics 300, "Survey of Mathematical Physics", a course that bridges the under-division and upper-division undergraduate physics major courses, introducing key mathematical tools while emphasizing how to think about math like a physicist.

Astronomy 444, "Applications of Gravitation," a new course on applications of general relativity for advanced undergraduate students.

Physics 211, "Elementary Physics," an algebra-based introduction to mechanics and thermodynamics.

Physics 211L, "Elementary Physics Laboratory", the laboratory co-requisite to Physics 211.

Physics 520, "Analytical Mechanics," a master's-level course in classical mechanics and special relativity.

Physics 225, "Fundamental Physics," a calculus-based introduction to mechanics. I am piloting a revision of this course using a flipped classroom, supported in part by the CSU Sustaining Success and Proven Course Resdesign redesign programs.

 

Curriculum Vitae

Geoffrey Lovelace
McCarthy Hall 601B, California State University, Fullerton
800 North State College Blvd., Fullerton, CA 92834
This email address is being protected from spambots. You need JavaScript enabled to view it.
 
Personal Data  
   
Born April 6, 1980, Huntingdon Valley, PA   
   
Employment  
   
Assistant Professor Aug. 2012 – present
California State University, Fullerton  
   
Research Associate Sep. 2007 – Aug. 2012
Cornell University  
   
Postdoctoral Scholar Jul. 2007 – Aug. 2007
California Institute of Technology  
   
Education  
   
Ph.D. in Physics Oct. 2002 – Jun. 2007
California Institute of Technology  
   
B.S. in Physics Aug. 1998 – May 2002
University of Oklahoma  
   
Visiting Appointments  
   
Visiting Associate Aug. 2012 – present
California Institute of Technology  

 

Download my complete CV, including a publication list and list of presentations, in PDF format.

 


Publications

My up-to-date publication list is available through the following:
* = CSUF undergraduate student co-author
+ = CSUF graduate student co-author
^ = CSUF alumni
 
40. Geoffrey Lovelace, Carlos O. Lousto, James Healy, Mark A. Scheel, Alyssa Garcia, Richard O'Shaughnessy, Michael Boyle, Manuela Campanelli, Daniel A. Hemberger, Lawrence E. Kidder Harald P. Pfeiffer, Bela Szilagyi, Saul A. Teukolsky, and Yosef Zlochower. "Modeling the source of GW150914 with targeted numerical-relativity simulations." (2016).
 
39. B. P. Abbott et al., for the LIGO Scientific Collaboration and the Virgo Collaboration. "GW151226: Observation of Gravitational Waves from a 22-Solar-Mass Binary Black Hole Coalescence." Phys. Rev. Lett. 116, 241103 (2016).
 
38. B. P. Abbott et al., for the LIGO Scientific Collaboration and the Virgo Collaboration. "Directly comparing GW150914 with numerical solutions of Einstein's equations for binary black hole coalescence." (2016).
 
37. B. P. Abbott et al., for the LIGO Scientific Collaboration and the Virgo Collaboration. "An improved analysis of GW150914 using a fully spin-precessing waveform model." (2016).
 
36. B. P. Abbott et al., for the LIGO Scientific Collaboration and the Virgo Collaboration. "Tests of general relativity with GW150914." Phys. Rev. Lett. 116, 221101 (2016).
 
35. B. P. Abbott et al., for the LIGO Scientific Collaboration and the Virgo Collaboration. "Properties of the Binary Black Hole Merger GW150914." Phys. Rev. Lett. 116, 241102 (2016).
 
34. B. P. Abbott et al., for the LIGO Scientific Collaboration and the Virgo Collaboration. "Observation of Gravitational Waves from a Binary Black Hole Merger." Phys. Rev. Lett. 116, 061102 (2016).
 
33. Prayush Kumar, Kevin Barkett, Swetha Bhagwat, Nousha Afshari*, Duncan A. Brown, Geoffrey Lovelace, Mark A. Scheel, and Bela Szilagyi. "Accuracy and precision of gravitational-wave models of inspiraling neutron star-black hole binaries with spin: Comparison with matter-free numerical relativity in the low-frequency regime." Phys. Rev. D 92, 102001 (2015).
arXiv:1507.00103 [gr-qc]
 
32. Mark A. Scheel, Matthew Giesler^, Daniel A. Hemberger, Geoffrey Lovelace, Kevin Kuper*, Michael Boyle, Bela Szilagyi, and Lawrence E. Kidder. "Improved methods for simulating nearly extremal binary black holes." Class. Quantum Grav. 32, 105009 (2015).
 
31. Geoffrey Lovelace, Mark A. Scheel, Robert Owen, Matthew Giesler^, Reza Katebi+, Bela Szilagyi, Tony Chu, Nicholas Demos*, Daniel A. Hemberger, Lawrence E. Kidder, Harald P. Pfeiffer, and Nousha Afshari*. "Nearly extremal apparent horizons in simulations of merging black holes." Class. Quantum Grav. 32, 065007 (2015).
arXiv:1411.7297 [gr-qc]
 
30. The LIGO Scientific Collaboration, the Virgo Collaboration, and the NINJA-2 Collaboration: J. Aasi et al. “The NINJA-2 project: Detecting and characterizing gravitational waveforms modelled using numerical binary black hole simulations.” Class. Quantum Grav. 31, 115004 (2014).
arXiv:1401.0939 [gr-qc]

29. Andrea Taracchini, Alessandra Buonanno, Yi Pan, Tanja Hinderer, Michael Boyle, Daniel A. Hemberger, Lawrence E. Kidder, Geoffrey Lovelace, Abdul H. Mroue, Harald P. Pfeiffer, Mark A. Scheel, Bela Szilagyi, Nicholas W. Taylor, and Anıl Zenginoglu. “Effective-one-body model for black-hole binaries with generic mass ratios and spins.” Phys. Rev. D 89, 061502 (2014).

28. Ian Hinder et al, “Error-analysis and comparison to analytical models of numerical waveforms produced by the NRAR Collaboration.” Class. Quantum Grav. 31, 025012 (2014).
arXiv:1307.5307 [gr-qc]

27. Abdul H. Mroue, Mark A. Scheel, Bela Szilagyi, Harald P. Pfeiffer, Michael Boyle, Daniel A. Hemberger, Lawrence E. Kidder, Geoffrey Lovelace, Serguei Ossokine, Nicholas W. Taylor, Anıl Zenginoglu, Luisa T. Buchman, Tony Chu, Evan Foley+, Matthew Giesler*, Robert Owen, Saul A. Teukolsky. “A catalog of 174 high-quality binary black-hole simulations for gravitational-wave astronomy.” Phys. Rev. Lett. 111, 241104 (2013).
 
26. Alexandre Le Tiec, Alessandra Buonanno, Abdul H. Mroué, Harald P. Pfeiffer, Daniel A. Hemberger, Geoffrey Lovelace, Lawrence E. Kidder, Mark A. Scheel, Béla Szilágyi, Nicholas W. Taylor, and Saul A. Teukolsky. “Periastron Advance in Spinning Black Hole Binaries: Gravitational Self-Force from Numerical Relativity.” Phys. Rev. D 88, 124027 (2013).
 
25. Tanja Hinderer, Alessandra Buonanno, Abdul H. Mroue, Daniel A. Hemberger, Geoffrey Lovelace, Harald P. Pfeiffer, Lawrence E. Kidder, Mark A. Scheel, Bela Szilagyi, Nicholas W. Taylor, and Saul A. Teukolsky. “Periastron advance in spinning black hole binaries: comparing effective-one-body and numerical relativity.” Phys. Rev. D 88, 084005 (2013).
 
24. Daniel Hemberger, Geoffrey Lovelace, Thomas J. Loredo, Lawrence E. Kidder, Mark A. Scheel, Bela Szilagyi, Nicholas W. Taylor, and Saul A. Teukolsky. “Final spin and radiated energy in numerical simulations of binary black holes with equal masses and equal, aligned or anti-aligned spins.” Phys. Rev. D 88, 064014 (2013).
                                                            
23. Geoffrey Lovelace, Matthew D. Duez, Francois Foucart, Lawrence E. Kidder, Harald P. Pfeiffer, Mark A. Scheel, and Bela Szilagyi. “Massive disk formation in the tidal disruption of a neutron star by a nearly extremal black hole.” Class. Quantum Grav. 30, 135004 (2013).
 
22. Daniel A. Hemberger, Mark A. Scheel, Lawrence E. Kidder, Bela Szilagyi, Geoffrey Lovelace, Nicholas W. Taylor, and Saul A. Teukolsky. “Dynamical excision boundaries in spectral evolutions of binary black hole spacetimes.” Class. Quantum Grav. 30, 115001 (2013).
 
21. David A. Nichols, Aaron Zimmerman, Yanbei Chen, Geoffrey Lovelace, Keith D. Matthews, Robert Owen, Fan Zhang, and Kip S. Thorne. “Visualizing Spacetime Curvature via Frame-Drag Vortexes and Tidal Tendexes III. Quasinormal Pulsations of Schwarzschild and Kerr Black Holes.” Phys. Rev. D 86, 104028 (2012).
arXiv:1208.3038 [gr-qc].
 
20. Fan Zhang, Aaron Zimmerman, David A. Nichols, Yanbei Chen, Geoffrey Lovelace, Keith D. Matthews, Robert Owen, and Kip S. Thorne. “Visualizing Spacetime Curvature via Frame-Drag Vortexes and Tidal Tendexes II. Stationary Black Holes.” Phys. Rev. D 86, 084049 (2012).
arXiv:1208.3034 [gr-qc].
 
19. Fan Zhang, Jeandrew Brink, Bela Szilagyi, and Geoffrey Lovelace. “A geometrically motivated coordinate system for exploring spacetime dynamics using a quasi-Kinnersley tetrad.” Phys. Rev. D 86, 084020 (2012).
arXiv:1208.0630 [gr-qc].
 
18. Bryant Garcia, Geoffrey Lovelace, Lawrence E. Kidder, Michael Boyle, Saul A. Teukolsky, Mark A. Scheel, and Bela Szilagyi. “Are different approaches to constructing initial data for binary black hole simulations of the same astrophysical situation equivalent?” Phys. Rev. D 86, 084054 (2012).
arXiv:1206.2943 [gr-qc]
17. Andrea Taracchini, Yi Pan, Alessandra Buonanno, Enrico Barausse, Tony Chu, Lawrence E. Kidder, Geoffrey Lovelace, Harald P. Pfeiffer, and Mark A. Scheel. “A prototype effective-one-body model for non-precessing spinning inspiral-merger-ringdown waveforms.” Phys. Rev. D 86, 024011 (2012).
 
16. Michael Boyle et al. “The NINJA-2 catalog of hybrid post-Newtonian/numerical-relativity waveforms for non-precessing black-hole binaries.” Class. Quantum Grav. 29, 124001 (2012).
 
15. Geoffrey Lovelace, Michael Boyle, Mark A. Scheel, and Bela Szilagyi. “High-accuracy gravitational waveforms for binary-black-hole mergers with nearly extremal spins.” Class. Quantum Grav. 29, 045003 (2012).
 
14. David A. Nichols, Robert Owen, Fan Zhang, Aaron Zimmerman, Jeandrew Brink, Yanbei Chen, Jeffrey D. Kaplan, Geoffrey Lovelace, Keith D. Matthews, Mark A. Scheel, and Kip S. Thorne. “Visualizing spacetime curvature via frame-drag vortexes and tidal tendexes: General theory and weak-gravity applications.” Phys. Rev. D 84, 124014 (2011).
 
13. Stephen R. Lau, Geoffrey Lovelace, and Harald P. Pfeiffer. “Implicit-explicit (IMEX) evolutions of single black holes.” Phys. Rev. D 84, 084023 (2011).
 
12. Robert Owen, Jeandrew Brink, Yanbei Chen, Jeffrey D. Kaplan, Geoffrey Lovelace, Keith D. Matthews, David A. Nichols, Mark A. Scheel, Fan Zhang, Aaron Zimmerman, and Kip S. Thorne. “Frame-dragging vortexes and tidal tendexes attached to colliding black holes: visualizing the curvature of spacetime.” Phys. Rev. Lett. 106, 151101 (2011).
 
11. Geoffrey Lovelace, Mark A. Scheel, and Bela Szilagyi. “Simulating merging binary black holes with nearly extremal spins.” Phys. Rev. D. 83, 024010 (2011).
 
10. Geoffrey Lovelace, Yanbei Chen, Michael Cohen, Jeffrey D. Kaplan, Drew Keppel, Keith D. Matthews, David A. Nichols, Mark A. Scheel, and Ulrich Sperhake. “Momentum flow in black-hole binaries: II. Numerical simulations of equal-mass, head-on mergers with antiparallel spins.” Phys. Rev. D 82, 064031 (2010). 
 
9. Geoffrey Lovelace. “Reducing spurious gravitational radiation in binary-black-hole simulations by using conformally curved initial data.” Class. Quantum Grav. 26, 114002 (2009). 
 
8. Geoffrey Lovelace, Robert Owen, Harald P. Pfeiffer, and Tony Chu. “Binary-black-hole initial data with nearly extremal spins.” Phys. Rev. D 78, 084017 (2008). 
 
7. Chao Li and Geoffrey Lovelace. “Generalization of Ryan’s theorem: Probing tidal coupling with gravitational waves from nearly circular, nearly equatorial, extreme-mass-ratio inspirals.” Phys. Rev. D 77, 064022 (2008).
 
T. Geoffrey Lovelace. “Topics in gravitational-wave physics.” Ph.D. thesis, California Institute of Technology (2007). 
 
6. Duncan A. Brown, Jeandrew Brink, Hua Fang, Jonathan R. Gair, Chao Li, Geoffrey Lovelace, Ilya Mandel, and Kip S. Thorne. “Prospects for detection of gravitational waves from intermediate-mass-ratio inspirals.” Phys. Rev. Lett. 99, 201102 (2007).
 
5. Harald P. Pfeiffer, Duncan A. Brown, Lawrence E. Kidder, Lee Lindblom, Geoffrey Lovelace, and Mark A. Scheel. “Reducing orbital eccentricity in binary black hole simulations.” Class. Quantum Grav. 24 S59 (2007).
 
4. Geoffrey Lovelace. “The dependence of test-mass thermal noises on beam shape in gravitational-wave interferometers.” Class. Quantum Grav. 24, 4491 (2007).
 
3. Hua Fang and Geoffrey Lovelace. “Tidal coupling of a Schwarzschild black hole and circularly orbiting moon.” Phys. Rev. D. 72, 124016 (2005).
 
2. Chung Kao, Geoffrey Lovelace, and Lynne H. Orr. “Detecting a Higgs pseudoscalar with a Z boson at the LHC.” Phys. Lett. B 567, 259 (2003).
 
1. Yun Wang and Geoffrey Lovelace. “Unbiased Estimate of Dark Energy Density from Type Ia Supernova Data.” Astrophys. J. 562 L115 (2001).

Movies

The following are a selection of movies from some recent numerical simulations that I have performed using the Spectral Einstein Code (SpEC) as part of my research in collarboation with the Simulating eXtreme Spacetimes (SXS) collaboration. For more, please see the SXS Collaboration's YouTube channel.

To learn more, visit https://www.black-holes.org/gw150914 !
 
Advanced LIGO saw gravitational waves from two black holes that merged over a billion light years from Earth. This computer simulation shows (in slow motion) what this would look like up close.  If this movie were played back in real time, it would last for about one third of a second.
 
In this movie, the black holes are near us, in front of a sky filled with stars and gas and dust. The black regions are the shadows of the two black holes: no light would reach us from these areas.  Light from each star or bit of gas or dust travels to our eyes along paths (light rays) that are greatly bent by the holes' gravity and by their warped spacetime. This is called "gravitational lensing."  Because of this gravitational lensing, the pattern of stellar and gas/dust images changes in fascinating ways, as the black holes orbit each other, then collide and merge.
 
The ring around the black holes, known as an "Einstein ring," arises from all the stars in a small region directly behind the holes; gravitational lensing smears their images into the shape of a ring.
 
The gravitational waves themselves would not be seen by a human near the black holes (though they would be felt!) and so do not show in this video, with one important exception: The gravitational waves that are traveling outward toward the small region behind the black holes disturb that region’s stellar images in the Einstein ring, causing them to slosh around in the ring, even long after the collision. The gravitational waves traveling in other directions cause weaker, and shorter-lived sloshing, everywhere outside the Einstein ring.
 
Credit: SXS Lensing

 

A computer simulation of the gravitational waves from the merging black holes that LIGO observed. Our three-dimensional space is shown as a two-dimensional surface, with one dimension removed. The black holes’ strong gravity curves the space near them into funnel shapes. As the black holes spiral together and merge into one, gravitational waves ripple outward. The movie is shown in slow motion, about 40 times slower than real time.

 

 

This movie shows two black holes that are spinning very rapidly (about 97% of the theoretical maximum) as they spiral together and merge. The simulation was published in Geoffrey Lovelace, Michael Boyle, Mark A. Scheel, and Bela Szilagyi, Class. Quantum Grav. 29, 045003 (2012) (http://arxiv.org/abs/1110.2229), and the movie was rendered by Cornell undergraduate researcher Robert McGehee, Jr.

The holes trace out their orbits as cyan and magenta lines, and their spins point along the white arrows. The colored surfaces are the holes' apparent horizons, shaded by the horizon vorticity (i.e., by how much an observer's body, oriented perpendicular to the horizon, would be twisted by the hole as it spins).
 
The black holes’ spins and the orbital angular momentum point in the same direction. Consequently, the holes experience an “orbital hangup” effect previously seen in simulations with lower spins: the holes merge much more slowly (after many more orbits) than if the spins were pointing in the opposite direction. This gives the system time to radiate enough angular momentum so that the final black hole will have a spin less than the theoretical maximum (the final hole ends up with about 95% of the maximum in this case). The initial holes have the highest spins of all binary-black-hole simulations to date.
 

 

 

 

Merging black holes are among the most promising sources of gravitational waves for the Advanced Laser Interferometer Gravitational-Wave Observatory (Advanced LIGO). Accurate predictions of the gravitational waves emitted by merging black holes---necessary both for detecting the waves in LIGO data and for estimating the properties of the binaries that generated those waves---can only be constructed using numerical simulations. In this talk, I will review recent progress and discuss current challenges in numerical simulations of merging, spinning black holes. After summarizing recent results (including the effects of black-hole spin on the holes' motion, the remnant hole's mass and spin, and the emitted gravitational waveforms), I will discuss the significant challenges that simulations of spinning binary black holes must still overcome. In particular, I will discuss the challenges of constructing and applying simulated waveforms to gravitational-wave data analysis, particularly when the spins are misaligned (causing orbital and spin precession) and when the holes are spinning near the theoretical maximum.