An asteroid-mass primordial black hole flying near a planet could perturb the planet’s orbit by a detectable amount.
Gravitational-wave signals from black hole mergers could reveal the presence of “gravitational atoms”—black holes surrounded by clouds of axions or other light bosons.
Subrahmanyan Chandrasekhar famously stated that black holes are “the most perfect macroscopic objects there are in the Universe: The only elements in their construction are our concepts of space and time.” His observation relates to the fact that astrophysical black holes, as described by the Kerr spacetime, can be characterized by just two parameters: mass and spin. However, things might get more complex. Theorists have predicted that if a bosonic field interacts with a Kerr black hole, perturbations in the field can grow to form a cloud around the black hole, creating a “gravitational atom,” in which the bosons surrounding the black hole behave somewhat like the electrons surrounding an atomic nucleus [1] (Fig. 1). What’s more, if such a gravitational atom is part of a binary involving a second black hole, excitations and ionization processes akin to those occurring in hydrogen atoms may affect how the black hole binary evolves.
Sharing stories over a cup of coffee; dancing in a group; cheering a football game in a crowd: these everyday rituals are among many different types of shared experiences that help humans develop social cohesion.
Anyone who has ever pet a cat or shuffled their feet across the carpet knows that rubbing objects together generates static electricity. But an explanation for this phenomenon has eluded researchers for more than two millennia.
Recent satellite data reveal that the Konya Basin in the Central Anatolian Plateau of Türkiye is continually being reshaped over millions of years, according to a new analysis led by Earth scientists at the University of Toronto.
In a few picoseconds (trillionths of a second), a small, thin piece of copper momentarily becomes dense plasma, specifically a state called warm dense matter, warm being a relative term—the metal is nearly 200,000 degrees Fahrenheit. With the short duration of a high-powered laser pulse, copper shifts from a solid state to a plasma state in an instant before it explodes. Understanding the progression of heat in the copper is an exciting breakthrough in physics relevant to the interior of giant planets and laser fusion fuel cores.
Scientists have discovered that ocean waves may become far more extreme and complex than previously imagined.
Researchers have demonstrated a new optical atomic clock that uses a single laser and doesn’t require cryogenic temperatures. By greatly reducing the size and complexity of atomic clocks without sacrificing accuracy and stability, this advance could lead to high-performance atomic clocks that are compact and portable.
A research team has used a machine learning approach to investigate the evolution of shell structure for nuclei far from the stability valley. The study, published in Physics Letters B and conducted by researchers from the Institute of Modern Physics (IMP) of the Chinese Academy of Sciences, Huzhou University, and the University of Paris-Saclay, reveals the double-magic nature of tin-100 and the disappearance of the magic number 20 in oxygen-28.
Scientists from the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory have shown that a type of qubit whose architecture is more amenable to mass production can perform comparably to qubits currently dominating the field. With a series of mathematical analyses, the scientists have provided a roadmap for simpler qubit fabrication that enables robust and reliable manufacturing of these quantum computer building blocks.