In their quest to discover physics beyond the Standard Model, physicists weigh the pros and cons of different search strategies.
Symmetry
By developing clever theories and conducting experiments with particle colliders, telescopes and satellites, physicists have been able to wind the film of the universe back billions of years—and glimpse the details of the very first moments in the history of our cosmic home. Take a (brief) journey through the early history of our cosmos.
It’s not always about what you discover. The LHC research program is famous for discovering and studying the long-sought Higgs boson. But out of the spotlight, scientists have been using the LHC for an equally important scientific endeavor: testing, constraining and eliminating hundreds of theories that propose solutions to outstanding problems in physics, such as why the force of gravity is so much weaker than other known forces like electromagnetism.
Physics professor Jason Nordhaus is working to reduce barriers to STEM for deaf and hard-of-hearing students, who face numerous barriers when trying to study technical STEM fields like physics. Physicists like Nordhaus are trying to change all that with specialized programs, classes and interpreter training, all aimed at reducing barriers in STEM.
Building a particle physics laboratory requires more than physicists. Fermilab archivist Valerie Higgins has authored a paper available in the online physics repository arXiv, and earlier this month she published an op-ed for Physics World on the importance of capturing perspectives from all parts of the laboratory. She sat down with Symmetry writer Lauren Biron to discuss her thoughts.
Can a theory that isn’t completely testable still be useful to physics? What determines if an idea is legitimately scientific or not? This question has been debated by philosophers and historians of science, working scientists, and lawyers in courts of law. That’s because it’s not merely an abstract notion: What makes something scientific or not determines if it should be taught in classrooms or supported by government grant money.
Scientists think that, under some circumstances, dark matter could generate powerful enough gravitational waves for equipment like LIGO to detect. Now that observatories have begun to record gravitational waves on a regular basis, scientists are discussing how dark matter—only known so far to interact with other matter only through gravity—might create these gravitational waves.
One of the latest discoveries from the LHC takes the properties of photons beyond what your electrodynamics teacher will tell you in class. For most of the year, the LHC collides protons, but for about a month each fall, the LHC switches things up and collides heavy atomic nuclei, such as lead ions. The main purpose of these lead collisions is to study a hot and dense subatomic fluid called the quark-gluon plasma, which is harder to create in collisions of protons. But these ion runs also enable scientists to turn the LHC into a new type of machine: a photon-photon collider.
A re-examination of a particle discovered in 2015 has scientists debating its true identity. A recent analysis by the LHCb collaboration at CERN raises questions about the identity of this pentaquark—and may have taken scientists back to square one in the search for a particle that could shed light on questions about color.
Some theorists have taken to designing their own experiments to broaden the search for dark matter. The trend of theorists proposing experiments has become so common that it’s almost expected of new students entering the field. The hope is that flooding the field with new ideas could finally lead to the discovery of dark matter.