On September 14, 2015, the two detectors of the Laser
Interferometer Gravitational-Wave Observatory (LIGO) observed a
gravitational-wave signal from the merger of a pair of black holes.
While this impressive technological triumph was celebrated...
The Institute sometimes spends money on risky ventures, giving
sustained support to people who work on unfashionable and dubious
projects. One example of a risky venture was Einstein, who worked
here for twenty years on unified field theories that...
The next time you are enjoying the sun’s warm rays, think of the
tremendous voyage those photons have taken to get to you.
Traveling, by definition, at the speed of light they left their
point of origin about eight minutes previously in a furious...
On July 14, 2015, the P5+1 group of world powers and Iran signed
a comprehensive nuclear agreement, aiming to limit Iran’s ability
to advance its nuclear program towards achieving nuclear weapons.
Eli Waxman, Professor at the Weizmann Institute of...
Matias Zaldarriaga, Professor in the School of Natural Sciences,
Scott Tremaine, Richard Black Professor in the School, Member Doron
Kushnir, and Junior Visiting Professor Nadia Zakamska discuss
LIGO's recent detection of gravitational waves...
Black holes are among the strangest predictions of Einstein’s
general theory of relativity: regions of spacetime in which gravity
is so strong that nothing—not even light—can escape. More
precisely, a black hole is a singularity in spacetime...
Albert Einstein finished his general theory of relativity in
November 1915, and in the hundred years since, its influence has
been profound, dramatically influencing the direction of physics,
cosmology, and mathematics. The theory upended Isaac...
“How big” is almost always an easier question to answer than
“how old.” Though we can measure the sizes of animals and plants
easily enough, we can often only guess at their ages. The same was
long true of the cosmos. The ancient Greeks Eratosthenes...
Five years ago, NASA’s Fermi Gamma-ray Space Telescope saw more
gamma rays than expected from the area around the center of our
galaxy. Many scientists suggest that the extra gamma rays could be
from the annihilation of dark matter particles. This...
The article by Wally Greenberg in the spring 2015 Institute
Letter mentions the anomalous axial current triangle diagram
and describes its connection with counting quark degrees of
freedom. This derives from a calculation I did when a
long-term...
