THE BOUNDARIES OF QUANTUM PHYSICS
BIO
Jeremias Pfaff Pfaff is studying towards a PhD at the University of Vienna. He is part of the Aspelmeyer Group, which explores the boundaries of quantum physics and gravity from both an experimental and gravitational perspective. The group has successfully measured the smallest gravitational force in the world by measuring the gravitational attraction between two gold spheres each spanning just two millimetres (0.07 inches) across.
Why can’t physics describe how gravity works at a subatomic scale?
It might be able to, we just don’t know yet. That’s why we did this experiment, because it’s mainly an experimental issue. Firstly, it’s just really difficult to measure gravity. It’s such a small force; you can imagine the gravity between the two spheres that we measure is 30 billion times smaller than the gravity that Earth pulls on one of the spheres. Just measuring that small force is tricky because you also have to shield it from all the other forces, such as magnetic and electrostatic, that are much stronger. If
