Black hole simulations on XSEDE supercomputers present new view of jets and accretion disks
Voracious absences at the center of galaxies, black holes shape the growth and death of the stars around them through their powerful gravitational pull and explosive ejections of energy.
Spacetime: A smoother brew than we knew
Spacetime may be less like foamy quantum beer and more like smooth Einsteinian whiskey, according to research led by physicist Robert Nemiroff of Michigan Technological University being presented today at the 221st American ...
Strict limit on CPT violation from gamma-ray bursts
Kenji Toma (Osaka Univ.), Shinji Mukohyama (Kavli IPMU, Univ. of Tokyo), Daisuke Yonetoku (Kanazawa Univ.) and their colleagues have used the photon polarization in three distant gamma-ray bursts detected ...
Is dark energy static or dynamic?
Accelerators can search for signs of Planck-scale gravity
For the first time, astronomers have measured the radius of a black hole
(Phys.org)—The point of no return: In astronomy, it's known as a black hole—a region in space where the pull of gravity is so strong that nothing, not even light, can escape. Black holes that can be billions ...
Looking at quantum gravity in a mirror
Einstein's theory of gravity and quantum physics are expected to merge at the Planck-scale of extremely high energies and on very short distances. At this scale, new phenomena could arise. However, the Planck-scale ...
Gravitational lens reveals details of distant, ancient galaxy
Thanks to the presence of a natural "zoom lens" in space, University of Chicago scientists working with NASA's Hubble Space Telescope have obtained a uniquely close-up look at the brightest gravitationally ...
Why we've got the cosmological constant all wrong
In the early universe, rapid expansion or something very weird
(PhysOrg.com) -- The widely-accepted theory of cosmic inflation states that our universe expanded rapidly in the moments after its birth, resulting in the immense expanse we see today.
Rapunzel, Leonardo and the physics of the ponytail
(PhysOrg.com) -- New research provides the first mathematical understanding of the shape of a ponytail and could have implications for the textile industry, computer animation and personal care products.
Physicists propose test for loop quantum gravity
A black hole unmasked
Black holes are among the most amazing and bizarre predictions of Einstein's theory of gravity. A black hole is thought to be point-like in dimension, but it is surrounded by an imaginary surface, or "edge," ...
One clock with two times: When quantum mechanics meets general relativity
The unification of quantum mechanics and Einstein's general relativity is one of the most exciting and still open questions in modern physics. General relativity, the joint theory of gravity, space and time ...