Anti-Matter Appearance

sean1234

I am curious as to how a single anti-matter atom looks, say anti-hydrogen. Further, Assuming you had the resources what would a visible (to the naked eye) molecule look like?

Antiphon

It would look identical to ordinary matter.

DrMark

google positronium, a hydrogen like atom composed of an electron and a positively charged antiparticle of the electron.

Igor_S

Anti-hydrogen has negatively charged nucleus (anti-proton) and positively charged particle (positron) orbiting around it. Supposedly it's spectrum should be exactly the same as the one from normal hydrogen, which would confirm something known as CPT symmetry. The color (or transparency) of macroscopic objects is due to their absorption and emission of the photons of visible light (an object is transparent if it doesn't absorb photons of visible light; they just pass through it, into our eyes). If there is a symmetry between matter and antimatter, a macroscopic object composed of anti-matter should have the same optical absorption and emission spectrum (I guess) and therefore it should have the same color (or remain transparent).