Lifeboat Foundation

Year 2021 face_with_colon_three

The quasi-local notion of an isolated horizon is employed to study the entropy of black holes without any particular symmetry in loop quantum gravity. The idea of characterizing the shape of a horizon by a sequence of local areas is successfully applied in the scheme to calculate the entropy by the S O(1, 1) BF boundary theory matching loop quantum gravity in the bulk. The generating function for calculating the microscopical degrees of freedom of a given isolated horizon is obtained. Numerical computations of small black holes indicate a new entropy formula containing the quantum correction related to the partition of the horizon. Further evidence shows that, for a given horizon area, the entropy decreases as a black hole deviates from the spherically symmetric one, and the entropy formula is also well suitable for big black holes.

The white dwarf’s brightness plunges in a mere 30 minutes—faster than any observed before.

A new study in published in Physical Review Letters analyzes the most complete set of galaxy clustering data to test the ΛCDM model, revealing discrepancies in the formation of cosmic structures in the universe, hinting at a new physics.

The ΛCDM model is the standard model of cosmology describing the universe’s evolution, expansion, and structure. It encompasses cold dark matter (CDM), normal matter and radiation, and the cosmological constant (Λ), which accounts for dark energy.

The model has been successful in explaining several cosmological observations, including the large-scale structure of the universe, the accelerating expansion of the universe, and the cosmic microwave background (CMB) radiation, which is the afterglow of the Big Bang.

A group of astronomers from numerous institutions have investigated a recently discovered nearby tidal disruption event known as ASASSN-22ci. They detected two luminous flares from this event. The finding was reported in a paper published Dec. 19 on the preprint server arXiv.

Tidal disruption events (TDEs) are astronomical phenomena that occur when a star passes close enough to a supermassive black hole and is pulled apart by the black hole’s tidal forces, causing the process of disruption.

Such tidally disrupted stellar debris starts raining down on the black hole and radiation emerges from the innermost region of accreting debris, which is an indicator of the presence of a TDE. All in all, the debris stream–stream collision causes an energy dissipation, which may lead to the formation of an accretion disk.

For the first time, a framework shows Einstein’s relativity aligns with quantum physics.

Scientists have finally figured out a way to connect the dots between the macroscopic and the microscopic worlds. Their magical equation might provide us answers to questions like why black holes don’t collapse and how quantum gravity works.

Albert Einstein’s theory of general relativity has revolutionized our understanding of gravity and the universe. However, it leaves some unanswered questions, particularly about singularities and black holes.

Recent studies suggest quantum mechanics could help resolve these mysteries and offer new insights into the fundamental nature of space-time and black holes.

General relativity is a theory developed by Albert Einstein to explain how gravity works.

Black holes are objects of mystery and dread from which nothing can escape… but could they also be the foundations of future civilizations of unimaginable might and size.

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Continue reading “Black Hole Technologies & Quasar Cannons” »

NSF NOIRLab rings in the New Year with a glittering galaxyscape captured with the Department of Energy-fabricated Dark Energy Camera, mounted on the U.S. National Science Foundation Víctor M. Blanco 4-meter Telescope at Cerro Tololo Inter-American Observatory in Chile, a Program of NSF NOIRLab. This ultra-deep view of the Antlia Cluster reveals a spectacular array of galaxy types among the hundreds that make up its population.

Galaxy clusters are some of the largest known structures in the known universe. Current models suggest that these massive structures form as clumps of dark matter and the galaxies that form within them are pulled together by gravity to form groups of dozens of galaxies, which in turn merge to form clusters of hundreds, even thousands.

Continue reading “Dark energy camera captures the glittering galaxies of the Antlia Cluster” »

Scientists at the Large Hadron Collider (CERN), the world’s most powerful elementary particle booster, have discovered the heaviest form of antimatter ever observed. This discovery is as significant as previous achievements at CERN, in particular the discovery of the Higgs boson and studies of B-meson decay.

The ALICE (A Large Ion Collider Experiment) has discovered an antimatter particle, antihyperhelium-4. It is the “evil twin” of another exotic particle, hyperhelium-4. This form of antimatter consists of two antiprotons, an antineutron, and an unstable antilambda particle, which in turn contains quarks.

Continue reading “Antihyperhelium-4: How scientists got a glimpse into the first seconds of the Universe” »