Reference Terms
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Mass
Mass is a property of a physical object that quantifies the amount of matter it contains. Unlike weight, the mass of something stays the same regardless of location. Mass is a central concept of classical mechanics and related subjects, and there are several forms of mass within the framework of relativistic kinematics. In the theory of relativity, the quantity invariant mass, which in concept is close to the classical idea of mass, does not vary between single observers in different reference frames. In classical mechanics, there are three types of mass or properties called mass: Inertial mass; passive gravitational mass; and active gravitational mass. Although inertial mass, passive gravitational mass and active gravitational mass are conceptually distinct, no experiment has ever unambiguously demonstrated any difference between them.
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Matter & Energy News
June 14, 2026
June 14, 2026 A new catalyst design could significantly improve the conversion of CO2 into methanol, an important fuel and chemical feedstock. Researchers separated key reaction steps across different catalyst sites, avoiding a long-standing trade-off between ...
June 12, 2026 A new nature-inspired membrane uses perfectly uniform one-nanometer pores to filter molecules with remarkable precision. The technology could transform industries such as pharmaceuticals and textiles by reducing energy consumption, improving water ...
June 12, 2026 Deep beneath the ground in China, the massive JUNO neutrino observatory has delivered its first major scientific breakthrough, achieving one of the most precise measurements yet of how elusive ...
June 12, 2026 Scientists at RIKEN have proposed a new way to make quantum systems synchronize in only one direction—like a one-way street for sound particles known as phonons. The breakthrough combines two quantum effects to create a form of one-way quantum ...
June 11, 2026 Scientists have developed an artificial photosynthesis system that essentially regulates itself, eliminating the need for batteries used in many current designs. The key innovation is an electrolyzer that automatically adapts to changing sunlight by ...
June 11, 2026 Scientists discovered that rice behaves in a highly unusual way: it weakens under rapid compression but stays stronger when pressure is applied slowly. Using this effect, they engineered a new ...
June 11, 2026 Scientists found that transfer learning can make the search for new physics in the universe much faster, slashing the need for expensive simulations. Yet the approach can backfire when AI relies too heavily on familiar patterns, potentially missing ...
June 10, 2026 MIT researchers have shown that one fuel can power both chemical and electric spacecraft thrusters, potentially transforming what small satellites can do. The approach combines quick bursts of speed with highly efficient long-range propulsion in a ...
June 8, 2026 Scientists used nanoscale gold metamaterials to supercharge heat transfer across tiny gaps, achieving up to four times more energy flow than similar conventional systems. The breakthrough could lead ...
June 6, 2026 A team at the University of Chicago has discovered a surprisingly simple way to create powerful quantum states that are normally difficult to produce. By making small adjustments to the energy levels ...
June 6, 2026 A team at the University of Minnesota discovered that changing a metal film's thickness by just a few nanometers can dramatically alter how it behaves electronically. The finding reveals a surprising new way to control metals and could help power ...
June 5, 2026 Scientists have uncovered unexpected quantum complexity inside cobalt, a metal long thought to be fully understood. Advanced measurements revealed a dense network of topological electronic states that remain robust at room temperature. These states ...
Latest Headlines
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June 14, 2026 What if some black holes aren’t black holes at all? A new theoretical study suggests that when a massive star collapses, it might not form a singularity hidden behind an event horizon. Instead, the ...
June 13, 2026 A bold claim that the universe’s accelerating expansion was an illusion has been put to the test—and failed. Researchers found that the study behind the controversy made key mistakes when ...
June 9, 2026 The mysterious Amaterasu particle may not be a proton at all. New research suggests that some of the most extreme cosmic rays could be ultraheavy atomic nuclei, heavier than iron, which are better ...
June 8, 2026 What if our biggest idea about reality is built on a hidden misunderstanding? A new philosophical look at space-time challenges the popular view that the past, present, and future all exist together ...
June 4, 2026 Researchers at EPFL have developed a chip-scale ultrafast laser that performs on par with traditional tabletop femtosecond lasers. The innovation could make advanced laser technologies far smaller, ...
June 4, 2026 Researchers have discovered how microscopic imperfections and atomic vibrations can be used to control a powerful quantum effect in an advanced material. The effect can turn alternating electrical ...
June 3, 2026 Scientists at Lawrence Livermore National Laboratory recreated part of the intense chaos inside a nuclear fireball to better understand how radioactive fallout forms. Their experiments revealed that ...
June 3, 2026 Researchers discovered a way to reverse the direction of energy flow in turbulence, challenging a theory that has stood for more than 80 years. The finding could open new possibilities for ...
June 2, 2026 A breakthrough hydrogen-production method could make clean fuel far cheaper and easier to generate. Researchers at the University of Birmingham developed a perovskite-based catalyst that splits water ...
June 2, 2026 Scientists have created a tiny chip that can generate, steer, and read light-based information all in one device, marking a major leap toward ultra-fast, energy-efficient computing. The breakthrough ...