cold matter

physics and astronomy

Also known as: nonrelativisitic matter

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July 19, 2026

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In physics and astronomy, "cold matter" refers to substances at extremely low temperatures, near absolute zero (-273.15 °C or -459.67 °F). At these temperatures, matter exhibits unusual properties like superconductivity (zero electrical resistance) and superfluidity (frictionless flow).12

In astronomy, cold matter also describes hydrogen clouds in interstellar space, which are primarily composed of neutral hydrogen atoms and are detectable via radio wavelengths.3

"Cold dark matter" is a theoretical form of dark matter composed of slow-moving particles, believed to have played a role in the formation of large-scale structures like galaxies in the early universe.4

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dark matter
…dark matter is relatively “cold,” or “nonrelativisitic,” meaning that the backbones of galaxies and clusters of galaxies are made of heavy, slow-moving particles. The absence of light from these particles also indicates that they are electromagnetically neutral. These properties give rise to the particles’ common name, weakly interacting massive…
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…dark matter is relatively “cold,” or “nonrelativisitic,” meaning that the backbones of galaxies and clusters of galaxies are made of heavy, slow-moving particles. The absence of light from these particles also indicates that they are electromagnetically neutral. These properties give rise to the particles’ common name, weakly interacting massive…
Read More