Gravitational Wave Science
BATON ROUGE – LSU faculty and students contributed to the detection of gravitational waves - opening a new window into the cosmos. Gravitational waves are ripples in spacetime, which arrive at Earth from a cataclysmic event in the distant universe. Detecting gravitational waves confirms a major prediction of Albert Einstein’s 1915 general theory of relativity.
The instruments at the Laser Interferometer Gravitational-wave Observatories, or LIGO, in Livingston, La. and Hanford, Wash. are the only such interferometers in the world that have been able to detect gravitational waves. The LIGO Observatories are funded by the National Science Foundation, or NSF, and were conceived, built and are operated by Caltech and MIT. The LIGO Livingston observatory is located on LSU property, and LSU faculty, students and research staff are major contributors to the 15-nation international LIGO Science Collaboration, or LSC. LIGO research is carried out by the LSC, a group of more than 1,000 scientists from universities around the U.S. and in 14 additional countries. More than 90 universities and research institutes in the LSC develop detector technology and analyze data; approximately 250 students are strong contributing members of the collaboration. The LSC detector network includes the LIGO interferometers and the GEO600 detector in Hanover, Germany.
LSU’s investment in gravitational-wave detection spans more than four decades, and is among the longest of the institutions contributing to the gravitational wave detections. LSU faculty, students and scholars have had leading roles in the development of several generations of gravitational wave detectors, in their commissioning and operation as well as the collaborations formed. This achievement is in part an outcome of LSU’s long-term vision and commitment to high-risk, high-potential scientific research.
LSU Physics and Astronomy Professors have been leaders in this major international scientific collaboration. Professor Gabriela González was the elected spokesperson for the LSC during the first two detections and Professor Joseph Giaime is the observatory head of LIGO Livingston.
LSU’s pioneering role in gravitational wave science began in 1970 with the arrival of William Hamilton, now professor emeritus, who along with Physics Professor Warren Johnson, built and operated previous-generation cryogenic bar gravitational wave detectors on campus for many years. LSU Associate Professor Thomas Corbitt focuses his research on advanced quantum metrology techniques for a future detector. These examples of faculty involvement represent more than 45 years of cutting-edge research, with state and institutional commitment, and long-standing multimillion dollar support from NSF producing educational opportunities for students and postdoctoral researchers, several of whom have gone on to professorial appointments around the world.
LSU’s campus is located 25 miles from LIGO Livingston in Baton Rouge. LSU has about 1,600 faculty; 31,000 students; and is classified by the Carnegie Foundation as “Doctoral/Research Universities—Extensive.” LSU is the only research university in the U.S. located close enough for students and faculty to engage in daily interactions with a LIGO observatory.
What is the LIGO Scientific Collaboration?
LIGO research is carried out by the LIGO Scientific Collaboration, or LSC, a group of more than1,000 scientists from universities around the U.S. and in 14 other countries. More than 90 universities and research institutes in the LSC develop detector technology and analyze data; approximately 250 students are strong contributing members of the collaboration.
The LSC detector network includes the LIGO interferometers and the GEO600 detector. It includes matching LIGO facilities in Livingston, LA and Hanford, WA. The location of the two observatories with another one in Europe creates a triangle that can verify astronomical observations.
LSU Physics and Astronomy Professor Gabriela González is the former elected spokesperson
for the LIGO Scientific Collaboration, a post she held for five years. LSU Physics
and Astronomy Professor Joe Giaime is the Observatory Head of LIGO Livingston.
What is LIGO Livingston?
LIGO Livingston is one of two laser interferometer observatories built to detect gravitational waves. About 40 people work at LIGO Livingston, which is about 36 miles north-east of Baton Rouge, Louisiana, where LSU is located. LIGO Livingston employs engineers, scientists and staff who support facilities, outreach and information technology to run the observatory. It is funded completely by the National Science Foundation, or NSF, and managed by the California Institute of Technology, or Caltech, and the Massachusetts Institute of Technology, or MIT. LSU owns the land, which is 180 acres, leased to the NSF until 2044.
LIGO Livingston began collecting data in 2005. In 2015, it received a major upgrade. The Advanced LIGO configurations increased the sensitivity of the instrumentation ten-fold. LIGO Livingston’s annual budget is $6-9 million per year.
About 17,000 people from the general public visit LIGO Livingston’s Science Education
Center each year. Free hands-on educational activities are available for school groups
as well as professional development training for educators.
What do we know about these first two detected gravitational waves?
LIGO made the first-ever observations of gravitational waves arriving on Earth from space, and the first detection of two black holes colliding on Sept. 14, 2015, at 4:51 a.m. CST.
The gravitational wave signal was detected in Livingston, La. and seven milliseconds later, the instrument at the LIGO observatory in Hanford, Wash. detected the same gravitational wave. On Dec. 26, 2015, at 03:38:53 UTC, scientists observed gravitational waves – ripples in the fabric of spacetime – for the second time.
These detections confirm that black holes exist in binary systems with solar masses. It also confirms aspects of Einstein’s Theory of General Relativity.
From this, we will be able to learn more about gravity near a black hole, where space-time is warped, that would not be possible to learn in other ways.
How do the LIGO instruments work?
The LIGO detectors are interferometers that shine a laser through a vacuum down two arms in the shape of an L that are each 4 kilometers in length. The light from the laser bounces back and forth between mirrors on each end of the L. Scientists measure the length of both arms using the light.
If there’s a disturbance in space-time, such as a gravitational wave, the time the light takes to travel 4 kilometers will be slightly different in each arm making one arm look longer than the other. LIGO scientists measure the interference in the two beams of light when they come back to meet, which reveals information on the space-time disturbance.
The discovery was made possible by the enhanced capabilities of Advanced LIGO, a major upgrade that increases the sensitivity of the instruments compared to the first-generation LIGO detectors, enabling a large increase in the volume of the universe probed – and the discovery of gravitational waves during its first observational run.
How do we know it’s a black hole?
The scientists compared the observation with Einstein’s prediction to identify that black holes produced this gravitational wave, how far they were, what the masses were and how large the final black hole was because of the energy emitted.
Which international institutions are part of this collaboration?
The NSF leads in financial support for Advanced LIGO. Funding organizations in Germany (Max Planck Society), the U.K. (Science and Technology Facilities Council, STFC) and Australia (Australian Research Council) also have made significant commitments to the project.
Several of the key technologies that made Advanced LIGO so much more sensitive have been developed and tested by the German UK GEO collaboration. Significant computer resources have been contributed by the AEI Hannover Atlas Cluster, the LIGO Laboratory, Syracuse University, the ARCCA cluster at Cardiff University, the University of Wisconsin-Milwaukee, and the Open Science Grid. Several universities designed, built, and tested key components and techniques for Advanced LIGO: The Australian National University, the University of Adelaide, the University of Western Australia, the University of Florida, Stanford University, Columbia University in the City of New York, and Louisiana State University. The GEO team includes scientists at the Max Planck Institute for Gravitational Physics (Albert Einstein Institute, AEI), Leibniz Universität Hannover, along with partners at the University of Glasgow, Cardiff University, the University of Birmingham, other universities in the United Kingdom and Germany, and the University of the Balearic Islands in Spain.
This is only the beginning of the field of gravitational wave astronomy. LIGO Scientific Collaboration scientists continue to conduct research on the existing data and expect to detect more astronomical events as the LIGO detectors and technology become more sensitive, and the French-Italian gravitational wave detector, VIRGO, located in Cascina, Italy begins to collect data this year.
Scientists anticipate detecting other events including neutron stars in our galaxy, other black holes and supernova explosions.
For additional background about the project, visit the following websites:
LIGO Scientific Collaboration: http://www.ligo.org/
Virgo Collaboration: http://www.virgo-gw.eu/
LIGO Laboratory: https://www.ligo.caltech.edu
Media Assets (CalTech): https://mediaassets.caltech.edu/gwave
LSU Department of Physics & Astronomy: http://www.lsu.edu/physics/
Support Research Discoveries in Physics & Astronomy http://www.lsu.edu/physics/heretowin/index.php
LIGO Research Publications:
Observation of Gravitational Waves from a Binary Black Hole Merger, Physical Review Letters:
GW151226: Observation of Gravitational Waves from a 22-Solar-Mass Binary Black Hole
Previous Press Releases:
Gravitational Waves Detected 100 Years After Einstein’s Prediction
Gravitational Waves Detected from Second Pair of Colliding Black Holes
LSU has a video uplink studio with live broadcast capabilities. Contact us to set up an interview with LSU gravitational wave researchers.
In the News:
LIGO Has Detected Gravitational Waves (Again)
Gravitational Waves Strike Twice
Gravitational Wave Observatory Finds More Colliding Black Holes
Contact Mimi LaValle
LSU Department of Physics & Astronomy
LIGO Scientific Collaboration
LSU Media Relations
LSU Media Relations