Anti-matter falls down, just like matter

The uncertainty of science: In a difficult particle physics experiment that carries large margins for error, scientists have determined that gravity appears to affect anti-matter the same as matter.

Quantitatively, the experiment indicates that antimatter experiences a pull from gravity that’s 75% as strong as that on ordinary matter, give or take 20%—a statistical agreement between the two. Hangst says 99.9% of physicists would have predicted the result. Still, he notes, “You have to do the experiment with an open mind.”

One must understand that, at atomic levels, the influence of gravity is practically nil. Extracting a measurment of its influence outside the other more powerful forces that dominate atomic particles, magnetism, the weak force, and the strong force, is difficult, to put it mildly.

The key is that the experiment result showed some influence of gravity, in the expected direction.