The theoretical physics and paradoxes of time travel often brush up against multiverse theory and the idea of alternate universes.
Antiferromagnetic spintronics offer high speed operations, and reduced issues with stray fields compared to ferromagnetic systems, however, antiferromagnets are typically more challenging to manipulate electrically. Here, Yang, Kim, and coauthors demonstrate electrical control of magnon dispersion and frequency in an α-Fe2O3/Pt heterostructure.
In a scientific breakthrough, Mount Sinai researchers have revealed the biological mechanisms by which a family of proteins known as histone deacetylases (HDACs) activate immune system cells linked to inflammatory bowel disease (IBD) and other inflammatory diseases.
This discovery, reported in Proceedings of the National Academy of Sciences (PNAS), could potentially lead to the development of selective HDAC inhibitors designed to treat types of IBD such as ulcerative colitis and Crohn’s disease.
“Our understanding of the specific function of class II HDACs in different cell types has been limited, impeding development of therapies targeting this promising drug target family,” says senior author Ming-Ming Zhou, PhD, Dr. Harold and Golden Lamport Professor in Physiology and Biophysics and Chair of the Department of Pharmacological Sciences at the Icahn School of Medicine at Mount Sinai. “Through our proof-of-concept study, we’re unraveling the mechanisms of class II HDACs, providing essential knowledge to explore their therapeutic potential for safer and more effective disease treatments.”
Close friend and coworker Thomas Hertog explores the groundbreaking physicist’s theories regarding the Big Bang’s beginnings on this, the sixth anniversary of Stephen Hawking’s passing.
I was appointed as Stephen Hawking’s PhD student in 1998 “to work on a quantum theory of the Big Bang.” Over the course of about 20 years, what began as a doctoral project evolved into a close collaboration that came to an end only six years ago, on March 14, 2018, when he passed away.
The mystery that drove our investigation during this time was how the Big Bang could have produced conditions that were so ideal for life. How should we interpret this enigmatic display of intent?
One such feature is lunar #lobate #scarps, long curvilinear landforms due to thrust fault movement (older rocks are pushed above younger units leading to crustal shortening.
#Lunar #Landforms indicate Geologically Recent #Seismic #Activity on the #Moon.
The moon’s steadfast illumination of our night sky has been a source of wonder and inspiration for millennia. Since the first satellite images of its surface were taken in the 1960s, our understanding of Earth’s companion through time has developed immeasurably. A complex interplay of cosmic interactions and planetary systems, the moon’s surface displays a plethora of landforms evidencing its history.
One such feature is lunar lobate scarps, long (10 km) curvilinear landforms resulting from thrust fault movement, where older rocks are pushed above younger units leading to crustal shortening. These are thought to be some of the youngest landforms on the moon, forming within the last ~700 million years (the Copernican of the lunar geologic timescale). For context, this is considered geologically “young” as the universe is estimated to be 13.7 billion years old.
Physicists haven’t yet ruled out the possibility that the universe has a complicated topology in which space loops back around on itself.
About 9.2 billion light-years from Earth is a colossal structure which has confounded astronomers.
The discovery might upend current cosmological theories.
What they’ve found is a 1.3-billion-light-year-across, almost perfect ring of galaxies. No such structure has been seen before. And it doesn’t match any known formation mechanism. It has been dubbed the “Big Ring.”
A new nucleosynthesis process denoted as the νr-process has been suggested by scientists from GSI Helmholtzzentrum für Schwerionenforschung, Technische Universität Darmstadt, and the Max Planck Institute for Astrophysics. It operates when neutron-rich material is exposed to a high flux of neutrinos.
Models for how heavy elements are produced within stars have become more accurate thanks to measurements by RIKEN nuclear physicists of the probabilities that 20 neutron-rich nuclei will shed neutrons.
Stars generate energy by fusing the nuclei of light elements—first hydrogen nuclei and then progressively heavier nuclei, as the hydrogen and other lighter elements are sequentially consumed. But this process can only produce the first 26 elements up to iron.
Another process, known as rapid neutron capture, is thought to produce nuclei that are heavier than iron. As its name suggests, this process involves nuclei becoming larger by rapidly snatching up stray neutrons. It requires extremely high densities of neutrons and is thus thought to occur mainly during events such as mergers of neutron stars and supernova explosions.
The first stars of the universe were monstrous beasts. Comprised only of hydrogen and helium, they could be 300 times more massive than the sun. Within them, the first of the heavier elements were formed, then cast off into the cosmos at the end of their short lives. They were the seeds of all the stars and planets we see today. A new study published in Science suggests these ancient progenitors created more than just the natural elements.
Except for hydrogen, helium, and a few traces of other light elements, all of the atoms we see around us were created through astrophysical processes, such as supernovae, collisions of neutron stars, and high-energy particle collisions. Together they created heavier elements up to Uranium-238, which is the heaviest naturally occurring element. Uranium is formed in supernova and neutron star collisions through what is known as the r-process, where neutrons are rapidly captured by atomic nuclei to become a heavier element. The r-process is complex, and there is still much we don’t understand about just how it occurs, or what its upper mass-limit might be. This new study, however, suggests that the r-process in the very first stars could have produced much heavier elements with atomic masses greater than 260.
The team looked at 42 stars in the Milky Way for which the elemental composition is well understood. Rather than simply looking for the presence of heavier elements, they looked at the relative abundances of elements across all the stars. They found that the abundance of some elements such as silver and rhodium doesn’t agree with the predicted abundance from known r-process nucleosynthesis. The data suggests that these elements are the decay remnants from much heavier nuclei of more than 260 atomic mass units.