By Chet Yarbrough
By Sean Carroll
Narrated by Jonathan Hogan
Sean Carroll is a theoretical cosmologist and senior research associate at the Department of Physics at the California Institute of Technology. His most recent book is “The Particle at the End of the Universe” which is focused on the story of Higgs boson, the widely and incorrectly termed “god particle”, that may have recently been found by CERN with Large-Hadron-Collider’ experiments.
The LHC is a wonder of the world. It enables scientists to experiment with particle physics at the most minute level of observation ever invented. It offers a mechanism for testing physics’ theories with experimentation formerly unavailable to science. The wonder of the machine is its ability to identify remains of particles never seen before. It offers the opportunity to see a skeleton of life’s elemental particles. More consequentially, the identification of a Higgs-boson like particle opens a whole new era of science research and theorization.
Carroll notes that the LHC is the largest machine in the world with a 17 mile circular tunnel built underground, below several Swiss towns. It was built by the European Organization for Nuclear Research. The LHC is a super cooled vacuum in a tunnel–designed to accelerate protons at near the speed of light for collisions that will reveal the remains of sub-atomic particles. The acceleration is achieved by using giant magnets that accelerate protons trapped in the tunnel. The LHC is in pursuit of an elemental particle, presumed missing because the total energy of known particles does not match the calculated energy of a specific field.
Carroll’s Physic’s explanations and the momentous importance of Higgs boson are clear and understandable. Early on, one finds Carroll explaining that Particle physics is a misleading category of scientific research. Carroll notes that Higgs boson is not a particle. It is a field. Further, Carroll notes–all that humankind perceives in the world is made up of fields, not particles.
With the advent of experimentally proven quantum mechanics, particle physics is transformed into field physics because of uncertainty. Every particle known to science is on the move. In order for one to view a particle—a proton, neutron, electron, etc., it must be frozen in time, which is not its natural state. Every particle exists within a field, a field in which particles are always in motion; always in one place or another.
Among many insights offered by Carroll, is the fundamental categorization of elemental particles. All particles are broken into two categories. One category is Fermion. The second is Boson. Fermions are elemental particles that are composed of matter. Bosons are elemental force particles that create fields like magnetism. Electrons, neutrinos, and quarks are fermions, the matter of the universe.
Photons, gluons, W bosons, and Z bosons are forces acting on fermions within fields. Bosons are massless which is why they are so difficult to identify. All bosons remain massless without the Higgs-boson mechanism (field). The Higgs-boson field creates mass out of combination of fermions and massless particles.
A useful analogy reported by Carroll explains how a Higgs-boson field creates mass. Imagine two people walking through a room filled with equally dispersed people. The people-filled’ room is the Higgs-boson field. The two people walking through the room are added massless boson particles. However, one of the two people is famous. The crowd congregates around the famous person (a boson) to create a mob (mass) of people while the less famous person passes through the room (the field) unnoticed.
Carroll explains that experimental proofs of quantum mechanics are the reason Higgs boson, or something like it, must exist. That is why the discovery is so important. Higgs boson is the field in which known particles of the universe gain mass. Without Higgs boson or something that works like Higgs boson, life would not exist.
Carroll offers other insights—about symmetry, super-symmetry, and breaking symmetry. He touches on dark matter and string theory. All are interestingly presented.
In general, Carroll crystallizes the importance of theoretical and experimental science. When listeners finish “The Particle at the End of the Universe, they will understand why Higgs boson is a magnificent discovery and the LHC is worth a nine-billion-dollar investment.