Physics at the LHC and Beyond: A New Window on the Nature of Matter, Spacetime and the Universe

December 9, 2020 Presentation to LCTG by Harvey Newman

A new era of exploration at the frontier of high energies opened in 2009 when the
Large Hadron Collider (LHC) began operation at CERN in the 27 km tunnel
beneath Switzerland and France that formerly housed the LEP electron-positron
collider. Scientists and engineers from around the globe completed 20 years of
designing and building the experiments, world-scale data systems and the collider
accelerator in time for the start of the physics program. Since that time the
accelerator and experiments have operated with remarkable performance,
reliability and efficiency, enabling a series of physics discoveries, most notably the
Higgs boson that is responsible for the masses of the fundamental particles in the
universe. The leap in center of mass energy and luminosity, and the analyzing
power of the LHC experiments, have opened a new level of precision in testing our
known theories, and new vistas in the search for new physics bearing on the nature
of matter and the fundamental forces and symmetries, beyond what we already
understand.

Since the 1990’s physicists have been faced with a variety of conceptual
challenges in our most fundamental well-understood theory, which does not
accommodate dark matter, which cannot be projected back to the energy scales of
the early universe, and which does not naturally unify the four forces of nature.
Our best theoretical ideas to extend this body of knowledge, such as
supersymmetry, and more exotic ideas such as the existence of extra spatial
dimensions, have not been found after more than a decade of searches by hundred
of physicists. It is clear that Nature is more subtle.

We will continue our explorations with much greater reach as the LHC program
progresses over the next 20 years, including a decade of exploration using ten
times the present volume of data (from 1 to several exabytes per year) at the High
Luminosity LHC (HL-LHC) starting around 2028. Beyond the LHC and HL-LHC
program itself, far into the 21 st century, plans are already underway for future
higher energy accelerators and experiments with greater precision and reach,
continuing to push back the limits of our knowledge until we make the next round
of discoveries; discoveries that could profoundly change our understanding of
spacetime and our universe.

I will introduce the status and outlook for the LHC, its past and present and near
term outlook, and provide a panorama of the future including some of the leading
programs such as a 100 km Future Circular Collider which are now under
consideration and in the conceptualization and early design phase.

Harvey Newman