Fostering Collaborative Research in Physics & Engineering

HEPL, founded in 1947 as Stanford's first Independent Laboratory, provides facilities and administrative structure enabling faculty to do research that spans across the boundaries of a single department or school—for example: physics & engineering or physics & biology/medicine. The Independent Laboratory concept, in many ways unique to Stanford, facilitates world-class research and teaching.
For more information about HEPL research, see the Research page.

News in Brief

Phptpvoltaic Retinal Implant image

Post-Doc researchers Brett Shapiro
and Hugo Paris, with Undergrad assistant
Litwan Gan, standing in front of the test
mass/mirror isolation system in the
Stanford LIGO Lab.

February 11, 2016

Stanford Researchers Celebrate Their Collaboration in the Technological Advances Enabling the Long-Sought Detection of Gravitational Waves by the LIGO Observatories

Excerpted from a news story by Bjorn Carey in the Stanford Report, February 11, 2016

Today an international team of scientists excitedly announced that they had directly observed gravitational waves, often described as ripples in the fabric of spacetime. The discovery of gravitational waves confirms a prediction that Albert Einstein made nearly 100 years ago to shore up his general theory of relativity.

The detection was made by the twin Laser Interferometer Gravitational-wave Observatory (LIGO) detectors, an experiment led by researchers at Caltech and MIT that includes more than 1,000 affiliated scientists, including several Stanford physicists and engineers who have played key roles in the program since it was launched. The instrument systems that made the detection possible were built in part on a legacy of interdisciplinary technological advances made by Stanford scientists.


Cover of 19 Nov 2015 Issue of Classical and Quantum Gravity

CQG 19 Nov 2015
Focus Issue on
Gravity Probe B

November 19, 2015

Volume 32, Issue #22 of the Journal, Classical and Quantum Gravity, Devoted Entirely to the Landmark,
48-Year Stanford/HEPL Gravity Probe B Experiment

In November 1915, Albert Einstein presented his field equations—the basis of his general theory of relativity—to the Prussian Academy of Science. Exactly 100 years later, a definative volume detailing the science, technologies and data analysis of the landmark Gravity Probe B experiment was published in a special focus issue of the Institute of Physics Journal, Classical and Quantum Gravity (Volume 32, Number 22, 19 November 2015).

Gravity Probe B (GP-B) was a 48-year HEPL/NASA/Lockheed Martin experimental physics mission that used four ultra-precise, spherical gyroscopes and a telescope, housed in a satellite orbiting 642 km (400 mi) above the Earth, to measure directly, with unprecedented accuracy, two extraordinary effects predicted by Einstein's general theory of relativity: 1) the geodetic effect—the amount by which the Earth warps the local spacetime in which it resides and 2) the frame-dragging effect—the amount by which the rotating Earth drags its local spacetime around with it.

First proposed in 1960 by Leonard Schiff, then chairman of the Stanford Physics Department and funded by NASA from 1963-2008, the GP-B spacecraft finally launched on 20 April 2004. The final results, verifying Einstein's predicted geodetic and frame-dragging measurements, were announced at a press conference at NASA Headquaters on 4 May 2011.