• Looking back
  • Astrophysics
  • Astrophysics/Cosmology
  • Astronomy
  • Numerical Relativity

The historic October 16 joint announcement by the U.S.-based Laser Interferometer Gravitational-Wave Observatory (LIGO) and the Europe-based Virgo detector of the first detection of gravitational waves produced by colliding neutron stars is doubly noteworthy. It’s also the first cosmic event observed in both gravitational waves and light—some 70 ground- and space-based observatories observed the colliding neutron stars. This is arguably the biggest moment to date in “multi-messenger astronomy.”

In a press release issued by LIGO and Virgo collaborations, National Science Foundation Director France A. Córdova comments, “It is tremendously exciting to experience a rare event that transforms our understanding of the workings of the universe. This discovery realizes a long-standing goal many of us have had, that is, to simultaneously observe rare cosmic events using both traditional as well as gravitational-wave observatories. Only through NSF’s four-decade investment in gravitational-wave observatories, coupled with telescopes that observe from radio to gamma-ray wavelengths, are we able to expand our opportunities to detect new cosmic phenomena and piece together a fresh narrative of the physics of stars in their death throes.”

Well before the development of today’s innovative technologies supporting this simultaneous gravitational-wave and optical observation, early research in numerical relativity at the University of Illinois at Urbana-Champaign helped to lay the theoretical foundation for it. In fact, many features of the discovery had been predicted in the early computational simulations of Professor of Physics and Astronomy Stuart Shapiro and his group.

  • Accolades

University of Illinois Professor of Physics and Astronomy Stuart Shapiro has been selected for the 2017 Hans A. Bethe Prize of the American Physical Society (APS). The Bethe Prize is conferred annually to a scholar who has made outstanding contributions to theory, experiment, or observation in astrophysics, nuclear physics, nuclear astrophysics, or closely related fields.

The citation reads, “For seminal and sustained contributions to understanding physical processes in compact object astrophysics, and advancing numerical relativity.”

  • Research

In less than the blink of an eye Einstein’s theory of relativity is on its way to becoming just another science fact. Scientists observed gravitational waves—ripples in the fabric of spacetime for the second time—and researchers at the National Center for Supercomputing Applications at the University of Illinois at Urbana-Champaign were part of the Ligo collaboration identifying the event.

Congratulations to the LIGO Scientific Collaboration on its historic discovery, the observation of gravitational waves! Your friends and colleagues at Physics Illinois are celebrating the spacetime ripples with you!

For the first time, scientists have observed ripples in the fabric of spacetime called gravitational waves, arriving at the earth from a cataclysmic event in the distant universe. This confirms a major prediction of Albert Einstein’s 1915 general theory of relativity and opens an unprecedented new window onto the cosmos.

Stuart Shapiro, a professor of physics and astronomy at Illinois, was appointed an NCSA research scientist by NCSA founder Larry Smarr two decades ago. A leading expert in the theory that underpinned the search for gravitational waves, Shapiro has developed software tools that can simulate on NCSA supercomputers like Blue Waters the very binary black hole merger and gravitational waves now detected by LIGO. Shapiro said he is thrilled by the discovery.

Shapiro comments on LIGO's discovery: "This presents the strongest confirmation yet of Einstein's theory of general relativity and the cleanest evidence to date of the existence of black holes. The gravitational waves that LIGO measures can only be generated by merging black holes – exotic relativistic objects from which nothing, including light, can escape from their interior."

  • Research
  • Astrophysics/Cosmology
  • Astrophysics

One of the principal strategies to indirectly detect dark matter is to search for the photons produced when it annihilates. Such searches look for gamma rays or x rays in regions of the sky where dark matter is known to be abundant. Professors Jessie Shelton, Stuart Shapiro, and Brian Fields at the University of Illinois at Urbana–Champaign have proposed to look inside dark matter spikes induced by the gravitational pull of supermassive black holes. Such measurements could test so called p-wave dark matter models.

  • Q&A
  • Astrophysics/Cosmology
  • Astrophysics
  • Cosmology
  • Relativity

The theory of general relativity is Einstein's theory of relativistic gravitation. It describes gravity as arising from the warping of space and time, or spacetime, caused by the presence of mass and energy. Mass curves spacetime, much like a stationary bowling ball curves a trampoline, and curved spacetime accelerates matter, much like a marble accelerates when placed on the warped trampoline.

  • In the Media

When astronomers try to simulate colliding giant black holes, they usually rely on simplified approximations to model the swirling disks of matter that surround and fuel these gravitational monsters. Researchers now report that, for the first time, they have simulated the collision of two supermassive black holes using a full-blown treatment of Einstein’s general theory of relativity, allowing a 3D portrayal of these disks of magnetized matter.


Stuart Shapiro of the University of Illinois at Urbana-Champaign presented movies of the simulations at a meeting of the American Physical Society in Baltimore, Maryland, on 13 April. His team had described elements of the study last November, in Physical Review D.