If antimatter is the counterpart of matter, does it fall in the other direction? The question does not resolve itself by playing with the prefix “anti”. At CERN, the ALPHA-g experiment used real antihydrogen atoms to examine their behavior under the effect of gravity.
Antiatoms are held in a vertical magnetic trap. The researchers gradually lower the barriers that enclose them, then observe where they escape and annihilate against the walls. It is not a question of filming a ball of antimatter placed on a table.
The results announced in 2023 show a tendency to fall down. They are compatible, in their uncertainties, with the expected Earth attraction. The experiment thus brings a direct observation where an intuition inspired by science fiction was not enough.
The measurement does not prove perfect equality of accelerations. It already responds to the meaning of the movement: “anti” does not mean a fall to the ceiling.
What we know
Attraction down observed; exact equality with ordinary acceleration not demonstrated by this measure.
To go to the source
References accessed October 11, 2026. Linked pages may be in another language.
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