Hypothetical particles are proposed physical entities that extend or modify established particle content in a given theoretical framework, typically introduced to resolve inconsistencies, explain unexplained phenomena, or complete symmetries in high-energy and gravitational physics. As physical systems, they are characterized by well-defined quantum numbers, interaction types, mass scales, and roles in Lagrangian formulations, yet they lack direct experimental confirmation. Examples in model-building include particles postulated in supersymmetry, grand unified theories, dark matter and dark energy models, and quantum gravity scenarios, where their properties are constrained by consistency with known symmetries, renormalizability, cosmological evolution, and precision tests of the Standard Model and general relativity.
Composing some 85% of the universe's total mass, dark matter betrays its presence only through gravity, unlike ordinary matter. Yet through new research published in Physical Review D, a team led by David Dunsky of New York ...
Using a detector filled with nearly 9 metric tons of liquid xenon, researchers have delivered some of the most sensitive dark matter results ever recorded. In the latest analysis from the XENON collaboration, working at the ...
Dark matter's existence is all but certain—astronomers believe it makes up about a quarter of the universe's total energy content—yet its true identity has eluded us for decades. Two of the leading candidates for dark matter ...
General Physics
Aug 5, 2026
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For decades, a theory in physics has postulated the existence of a mirror world whose interaction with our own reality is extremely feeble. The particles in this mirror universe are also thought to be candidates for dark ...
General Physics
Jul 28, 2026
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What if the Higgs boson found in 2012 is not alone but is the only sibling we have encountered so far? Scientists at CERN discovered the particle that year, and it was a major discovery because it explained how other particles ...
General Physics
Jul 23, 2026
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Researchers in the U.S. have carried out the most stringent tests to date of the idea that an ultraviolet glow in the atmospheres of giant planets could partly arise through the indirect interaction between dark matter and ...
The mysterious substance that binds galaxies together could naturally be "in tune" with a hidden fifth dimension, according to a new University of Sheffield theory aiming to shed light on one of science's biggest enigmas: ...
General Physics
Jul 13, 2026
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Dark matter accounts for 85% of the matter in the universe, but scientists still do not know what it is made of. A study, published in Physical Review Letters, by Rice University researchers proposes a detector design that ...
General Physics
Jul 2, 2026
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The world's most powerful particle accelerator will shutter operations Monday for four years of renovations to dramatically boost its collision capacity and the potential for unlocking one of the greatest mysteries of the ...
General Physics
Jun 27, 2026
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Belgian scientist Francois Englert, a particle physics specialist who won the Nobel Prize in 2013 for his work on the Higgs boson, has died at 93.
General Physics
Jun 20, 2026
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