In 1932, Paul Dirac proposed the existence of a new kind of matter, which he called “negative matter”. This was a startling idea at the time, and it took many years for scientists to accept that such a thing could exist. In the meantime, Dirac had made another important discovery: that electrons can have an effect on each other even when they are not in contact with each other. This led to the development of quantum electrodynamics, or QED.
QED is the theory that explains how electromagnetic fields interact with charged particles such as electrons. It is one of the most accurate theories in all of physics; its predictions have been verified to better than one part in a trillion. QED is also remarkable because it is the only physical theory that has been developed using only first principles; that is, without making any assumptions about what happens at very small scales.
The success of QED led physicists to believe that they could develop a similar theory for the other forces of nature: gravity and the strong and weak nuclear forces. These efforts eventually resulted in the development of quantum chromodynamics (QCD) and the Standard Model of particle physics. However, these theories do not explain everything we see in the Universe; they leave out some important phenomena, such as dark energy and dark matter.
One way to try to understand these missing pieces is by studying matter at extremely high densities and energies, conditions that can be found only in astrophysical objects such as neutron stars and black holes. Another way is to look for new particles that might make up dark matter or modify our understanding of gravity. These are just two examples of research areas supported by Fermi National Accelerator Laboratory’s Physics Division through its Foundation For Fundamental Research On Matter program.