You may not be able to hear it, but all solid materials make a sound. In fact, atoms—bound in lattices of chemical bonds—are never silent nor still: Under the placid surface of each and every object in our surroundings, a low hum hovers or a high-energy squeak titters.

As atoms vibrate in their lattices, they do so by either all moving in the same direction, in which case their collective vibration shows up as a low humming sound, or by moving in opposite directions from one another, giving rise to an energetic vibration that registers as a bright squeak or titter.

Why phonon vibrations matter
“These vibrations are crucial for both classical or quantum electronics,” said Hanyu Zhu, a corresponding author on a new study published in Physical Review Letters that reports an unus...

Astronomers have an answer for a long-running mystery in astrophysics: why is the growth of supermassive black holes so much lower today than in the past? A study using NASA’s Chandra X-ray Observatory and other X-ray telescopes found that supermassive black holes are unable to consume material as rapidly as they did in the distant past. The results appeared in the December 2025 issue of The Astrophysical Journal.

Ten billion years ago, there was a period that astronomers call “cosmic noon,” when the growth of supermassive black holes (those with millions to billions of times the mass of the sun) was at its peak across the entire history of the universe. Between cosmic noon and now, however, astronomers have seen a major slowdown in how rapidly black holes are growing.

“A longst...

Microscopic sensors that are as thin as a strand of hair but capable of taking multiple measurements simultaneously could revolutionize the diagnosis and monitoring of diseases like cancer. Researchers from Adelaide University’s Institute for Photonics and Advanced Sensing and the University of Stuttgart in Germany worked together to develop the tiny sensors using state-of-the-art, ultrafast 3D microprinting technology.

The unique sensors target specific biomarkers and are printed directly onto the tip of optical fibers...

New UNLV-led research is helping to unravel clues to a cosmic mystery that has eluded scientists for decades. Cataclysmic variables (CVs) are binary star systems in which primary stars—incredibly dense and compact white dwarfs—accumulate material from nearby companion stars. The material spirals in towards the white dwarf through what is known as an accretion disk. These deep space systems are responsible for a number of cosmic phenomena, including sudden bursts of light known as classical novae that temporarily appear to resemble new stars before fading away over time.

A long-standing mystery in cataclysmic variables
Modern astronomical instruments have enabled scientists to understand many of the mechanisms that drive CVs...