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Density
Density is a measure of mass per unit of volume. Density is a measure of mass per volume. The average density of an object equals its total mass divided by its total volume. An object made from a comparatively dense material (such as iron) will have less volume than an object of equal mass made from some less dense substance (such as water). Perhaps the highest density known is reached in neutron star matter. The singularity at the centre of a black hole, according to general relativity, does not have any volume, so its density is undefined.
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Matter & Energy News
April 10, 2026
Apr. 10, 2026 Scientists have proposed a surprising new way to detect gravitational waves—by observing how they change the light emitted by atoms. These waves can subtly shift photon frequencies in different directions, leaving behind a detectable signature. ...
Apr. 10, 2026 A strange new kind of superconductivity has been uncovered in uranium ditelluride (UTe2), where electricity flows with zero resistance—but only under extremely strong magnetic fields that should normally destroy it. Even more surprising, the ...
Apr. 10, 2026 Perovskite solar cells shouldn’t work as well as they do—but they do. Scientists have now discovered that defects inside the material actually help, creating networks that separate and guide electric charges efficiently. Using a novel imaging ...
Apr. 10, 2026 A new chip design from UC San Diego could make data centers far more energy-efficient by rethinking how power is converted for GPUs. By combining vibrating piezoelectric components with a clever circuit layout, the system overcomes limitations of ...
Apr. 6, 2026 Quantum circuits are supposed to gain power as they grow longer, but noise changes the picture. A new study finds that earlier steps in these circuits gradually lose their impact, with only the final layers really mattering. As a result, deep ...
Apr. 4, 2026 Scientists have taken a major step toward futuristic energy tech by building a working prototype of a quantum battery—one that can charge, store, and release energy using the strange rules of quantum physics instead of chemistry. This tiny, ...
Apr. 4, 2026 A new breakthrough is transforming MXenes—ultra-thin, high-tech materials—into something far more powerful and precise. Researchers have developed a cleaner, more controlled way to build these materials using molten salts and iodine, eliminating ...
Apr. 2, 2026 Fusion scientists have solved a long-standing mystery inside tokamaks, the donut-shaped machines designed to harness fusion energy. For years, experiments showed that escaping plasma particles hit one side of the exhaust system far more than the ...
Mar. 31, 2026 Scientists have transformed a groundbreaking 2D nanomaterial called MXene into an even more powerful 1D form—tiny scroll-like tubes that are incredibly thin yet highly conductive. By rolling flat ...
Mar. 31, 2026 A new shape-shifting material can change both its texture and color in seconds, inspired by the camouflage abilities of octopuses. By precisely controlling how a polymer swells with water, ...
Mar. 31, 2026 Scientists have taken lasers beyond light and into the realm of sound, creating a breakthrough “phonon laser” that manipulates tiny vibrations at the quantum level. By dramatically reducing noise ...
Mar. 31, 2026 Perovskite crystals can dramatically and reversibly change shape when hit with light, a behavior not seen in conventional semiconductors. This effect, called photostriction, can be finely tuned depending on the light’s intensity and color. ...
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Apr. 10, 2026 A mysterious glow of gamma rays at the center of the Milky Way has long hinted at dark matter, but the lack of similar signals in smaller dwarf galaxies has cast doubt on that idea. Now, researchers ...
Apr. 8, 2026 A bizarre, record-breaking neutrino detected in 2023 may have originated from an exploding primordial black hole—a relic from the early universe. ...
Apr. 7, 2026 Scientists have zoomed in on how phosphoric acid moves electrical charges so efficiently in both biology and technology. By freezing a key molecular pair to extremely low temperatures, they found it ...
Apr. 6, 2026 Scientists have taken a major step toward probing one of physics’ biggest mysteries—how gravity and quantum mechanics fit together—by creating the first unified way to detect tiny “ripples” ...
Apr. 3, 2026 Saturn’s magnetic field isn’t the smooth, symmetrical shield scientists see around Earth. Instead, it’s noticeably skewed, and researchers now think they understand why. By analyzing years of ...
Mar. 30, 2026 Scientists at the University of Waterloo have uncovered a bold new way to explain how the universe began—one that could reshape our understanding of the Big Bang. Instead of relying on ...
Mar. 30, 2026 Scientists have discovered something that seems almost impossible: under the right conditions, ordinary liquids can snap apart like solid objects. In experiments, researchers found that when certain ...
Mar. 29, 2026 Scientists have finally found a hidden “critical point” in supercooled water that explains why it behaves so strangely. At this point, two different liquid forms of water merge, triggering ...
Mar. 29, 2026 A team of physicists set out to test some of the most exciting claims in quantum computing—and found a very different story. Instead of confirming breakthroughs, their careful replication studies ...
Mar. 29, 2026 A new holographic storage technique uses light in three dimensions to dramatically increase how much data can be stored. It encodes information ...