Illustration of the first gravitational wave event observed by LIGO in 2015. The detected wave forms from LIGO Hanford (orange) and LIGO Livingston (blue) are superimposed beneath illustrations of the merging black holes. (Photo courtesy of Aurore Simmonet, Sonoma State University
Ten years ago, a faint ripple in the fabric of space-time forever changed our understanding of the Universe. On Sept. 14, 2015, scientists at the Laser Interferometer Gravitational-Wave Observatory (LIGO) made the first direct detection of gravitational waves—disturbances caused by the collision of two black holes more than a billion light-years away. The signal, named GW150914, was observed simultaneously at two LIGO sites: LIGO Livingston Observatory in Livingston, Louisiana, and LIGO Hanford Observatory in Hanford, Washington. This historic breakthrough confirmed a century-old prediction by Albert Einstein and opened a new window into the cosmos.
Researchers from Syracuse University’s Department of Physics were key leaders in the design, construction and operation of LIGO. Physics Professors Stefan Ballmer, Duncan Brown and Peter Saulson led the University’s gravitational-wave astronomy group as the discovery of gravitational waves launched a new era of astrophysics. Since 2015, Craig Cahillane, Alexander Nitz and Georgia Mansell—all contributors to the discovery—have joined the University as physics professors.
Syracuse was the first university outside the LIGO Laboratory to establish a dedicated research group, thanks to Saulson’s early leadership and vision. His recruitment of Brown and Ballmer laid the foundation for a legacy of excellence in gravitational wave science.
“Syracuse has been at the forefront of gravitational-wave astronomy since the beginning of the field,” says Duncan Brown, vice president for research at and Charles Brightman Endowed Professor of Physics. “Our students were part of the team during the first discoveries, and Syracuse continues to advance the field.”
Revisit a 2015 video featuring A&S researchers as they discuss their groundbreaking discovery:
The 2015 detection was not just a scientific triumph—it was a turning point. In the years since, LIGO has detected hundreds of black hole collisions thanks to advances in detector technology. In January 2025, LIGO detected its strongest gravitational wave signal to date, produced by the merger of two black holes in a distant galaxy that had nearly the same masses as those that produced the first LIGO event in 2015. The clarity of the signal allowed physicists to test general relativity in unprecedented detail, confirming a fundamental theorem proposed by Stephen Hawking: that a black hole’s surface area can only grow, never shrink.
The stretching of space in the 2025 black hole merger (top) closely resembles the first observed event in 2015 (bottom), but thanks to improved detector sensitivity and reduced noise, the newer signal appears much more clear. (Courtesy: C. Bickel/Science)
Syracuse researchers have remained at the cutting edge of this rapidly evolving field. In 2023, they launched the Center for Gravitational Wave Astronomy and Astrophysics, directed by Ballmer. The center is now one of the largest experimental gravitational-wave physics groups in the United States. It brings together experts in quantum optics, high-power lasers, astrophysical modeling and seismology to design next-generation observatories like Cosmic Explorer.
Learn more about gravitational wave research at Syracuse University:
Their work on the Cosmic Explorer project promises to revolutionize gravitational wave detection. With vastly improved sensitivity, it will observe black hole and neutron star collisions across cosmic time, reaching back to the remnants of the Universe’s first stars. “Advanced LIGO observes gravitational waves from a black hole merger about every third day,” says Ballmer. “But Cosmic Explorer will detect new events every few minutes, with a reach to the earliest stages of the Universe.”
Physicists from Syracuse University, Massachusetts Institute of Technology, Pennsylvania State University, California State University, Fullerton and the University of Florida during a proposal-writing workshop at SU’s Minnowbrook Conference Center in 2022. The collaboration resulted in over $9M of federal funding to the Cosmic Explorer project.
Syracuse’s leadership in this endeavor is backed by multiple National Science Foundation design awards, covering everything from site selection and optical design to data infrastructure. Faculty members Mansell, Cahillane, Nitz, Eric Coughlin, Steve Penn, Collin Capano and Ruslan Podviianiuk are pushing the boundaries of what gravitational wave observatories can achieve, and Earth and Environmental Sciences faculty Josh Russell and Chris Scholz are spearheading the search for a suitable site for the Cosmic Explorer observatory. Their work ensures that Syracuse will remain a central player in the field well into the 2050s and beyond.
This year’s anniversary is also marked by a profound loss: the passing of MIT Professor Emeritus Rainer “Rai” Weiss, co-founder of LIGO and one of the most influential physicists of our time. Weiss, who died on Aug. 25 at the age of 92, conceived the original design for LIGO and shared the 2017 Nobel Prize in Physics for his role in the first detection.
Weiss collaborated closely with Syracuse faculty during his career and participated in a memorable 2017 panel discussion in New York City alongside Brown, Saulson and Ballmer.
Syracuse physics Professors Stefan Ballmer (left) and Duncan Brown (middle) with Nobel Prize-winning physicist Rai Weiss at the Explorer’s Club in New York City.
“Weiss’s legacy lives on in every gravitational wave detected and every student inspired by his work,” says Ballmer. “His vision and ingenuity laid the groundwork for a global collaboration that continues to expand our understanding of the Universe.”
Syracuse University’s journey from theoretical foundations to experimental breakthroughs is a testament to decades of dedication, innovation and collaboration. From Peter Bergmann’s post-war work with Einstein to Joshua Goldberg’s efforts to bring world-class physicists to campus, the University has long been a beacon of gravitational wave research.
“As we mark a decade since the first detection of gravitational waves, Syracuse stands at the forefront of a scientific revolution,” Ballmer says. “We’re not just commemorating a milestone—we’re embracing the spirit of discovery that defines our University and propels us toward answering some of the Universe’s deepest mysteries.”
