illuminating science

I just saw this article on Nature News about “positronium” and making exotic atoms and molecules. Positronium is similar to a hydrogen atom, which has a single negatively charged electron orbiting a positively charged proton. But instead of a proton you use a positron, an anti-electron, which has the same mass an an electron but a positive charge instead. It turns out that this atom, despite being made of antimatter and matter (which want to annihilate each othe!), can survive for a short time (about a billionth of a second) before that happens. “How cool!” I thought to myself, and marvelled for a moment at modern science. Then, I realised that this was done in the 1950’s - 50 years ago! It’s hard to believe that we could so easily make antimatter and manipulate it that long ago, when you think of how “primitive” science labs must have been compared to what we have now!

This new research is exploring the possibility that even though the positronium atoms are very shortlived, two of them might form together to create a positronium molecule, basically like two hydrogen atoms bond to make a hydrogen molecule (H₂). It might all sound a little esoteric, but positrons are vital for Positron Emission Tomography (PET) which is an important medical imaging technique. So who knows where this research will lead?