All you wanted to know about antimatter


What, exactly, is antimatter? Here is a chance for you to find out. Eric Hessels (left), York CRC in Atomic Physics and professor in York’s Department of Physics & Astronomy, Faculty of Pure & Applied Science, will give a lecture entitled “Making Antimatter” on Sunday, Feb. 15, at 3pm in the J.J.R. Macleod Auditorium, Medical Sciences Building, University of Toronto, 1 King’s College Circle.


Hessels’ lecture is part of the free public lecture series of the Royal Canadian Institute for the Advancement of Science. The talk will delve into the process of making antihydrogen and what we might learn from studying these antimatter.


Here is a synopsis of Hessels’ lecture:


Ordinary matter is composed of atoms that are made up of particles, such as protons, neutrons and electrons. For example, the hydrogen atom consists of one electron orbiting around a single proton.


Right: NASA photo depicting a stream of antimatter coming from the vicinity of a black hole


Similarly, antimatter is composed of antiparticles, such as antiprotons, antineutrons and antielectons. (Antielectrons are usually referred to as positrons.) Only recently have we been able to combine these antiparticles into antiatoms. Specifically, we have caused positrons to orbit around antiprotons to form antihydrogen atoms.


The aim of our international collaboration is to suspend these antiatoms in a magnetic field so that we can study them. This talk will discuss the process of making antihydrogen and what we might learn from studying these antimatter atoms.


More about Eric Hessels


Hessels, along with his team at York, is working with the international Antihydrogen Trap (ATRAP) group at Harvard University on a method to trap so-called antiatoms long enough to conduct experiments. His work also involves measuring the energies and orbits of helium atoms to provide the most accurate measurement of the “fine structure constant,” the fundamental constant of nature that determines the strength of the electric and magnetic forces between charged objects. This fundamental constant is not only relevant to magnets and electricity, but to how atoms, chemicals and solid objects are held together. His research promises to determine the difference between matter and antimatter.