Does antihydrogen fall with g to within 1 percent?
In plain words
In 2023 the first direct experiment showed that antihydrogen falls down, not up, but only to about 20% precision. A 1% measurement would test whether antimatter feels gravity exactly like matter.
Precise statement
ALPHA-g measured the vertical acceleration of antihydrogen as $a_g = (0.75 \pm 0.13 stat+sys \pm 0.16 simulation) g$ (2023). Determine $a_g/g$ with total uncertainty below 0.01 and test whether it differs from 1.
What would settle it
A laser-cooled antihydrogen release or interferometric measurement (ALPHA-g, GBAR or AEgIS) reaching $1\%$ uncertainty on $a_g$.
Status in the literature
Unverified note: it names recent work and was partly written without a live literature search; it awaits a check by an editor.
No measurement of $a_g$ more precise than the 2023 ALPHA-g result has been published as of 2026; antihydrogen laser cooling (2021) is the stated prerequisite for the next step.
Results
No results have been posted on this problem yet.
Post a result · how results are checked
Sign in to follow or save this problem
Comments (0)
Comments are not records: they are not signed, stamped or logged. How comments work
No comments yet.
Sign in to comment.