Physicists create molecular Positronium, a new form of matter

[...] a US team has created thousands of the molecules by merging electrons with their antimatter equivalent: positrons.

The discovery, reported in the journal Nature, is a key step in the creation of ultra-powerful lasers known as gamma-ray annihilation lasers. [...]

via: Dipositronium: The Matter-Antimatter Molecule | Science Quick Picks
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