A 2011 earthquake bounced a seismic wave off Earth’s core, nudging Japan east - Science News

We’re sharing this article early to provide faster access to peer-reviewed, accepted research. It is citable and carries a permanent DOI. This version is subject to further edits and will be replaced automatically by the final Version of Record. All legal disclaimers apply. AbstractAccording to the third theorem of similarity, a layered physical model was established using two types of materials with different shear stiffnesses. This model was used to represent the prototype in shaking table tests, and the influences of the burial depth and thickness of the hard interlayer on the amplification factor and on the characteristic parameters of the response spectrum were analysed and studied. The study revealed the following: (1) The influence trends of the burial depth and thickness of the hard interlayer on the amplification factor and on the characteristic period of the response spectrum obtained from the shaking table tests were found to be consistent with those obtained from a one-dimensional equivalent linearization calculation. This comparison serves as a verification of the experimental results rather than as an independent conclusion.

The polar vortex, a swirling mass of cold air encircling the North Pole, is sometimes disrupted by sudden stratospheric warming (SSW) events, unleashing waves of frigid air that penetrate farther south than usual. Temperatures across North America and Europe drop precipitously when this happens, but such events remain hard to predict, meaning we can't easily warn people when SSW is imminent.

New results from the STAR experiment at the Relativistic Heavy Ion Collider (RHIC) provide strong evidence that smashing oxygen nuclei together at nearly the speed of light generates a quark-gluon plasma (QGP), a type of matter that existed just after the birth of the universe. The data, just published in Physical Review Letters, show that energetic jets of particles lose energy as they traverse the hot, dense matter left in the collision's wake.