What is a boson?
- A boson is a subatomic particle that carries force, with an integer spin quantum number in particle physics.
- Bosons are one of two fundamental subatomic particle types; fermions, which have half-odd-integer spin, are the other.
- Every subatomic particle that can be seen is either a boson or a fermion.
What is a Higgs Boson?
- The Higgs particle is a boson. All physical forces are assumed to be caused by bosons, which are particles. Photons, W and Z bosons, and the gluon are some of the other known bosons.
- The Higgs boson is the fundamental particle associated with the Higgs field, a field that gives mass to other fundamental particles such as electrons and quarks.
- The Nobel Prize-winning discovery of the Higgs boson (commonly known as the “God particle”) in 2012 confirmed the Standard Model of physics, which also predicts that a Higgs boson will decay to a pair of bottom quarks around 60% of the time. Peter Higgs was the first to hypothesise that this particle may exist in the 1960s.
- The Standard Model of particle physics is a hypothesis that classifies all known constituent particles and defines three of the four known fundamental forces in the universe (electromagnetic, weak, and strong interactions, excluding gravitational force).
- Each fundamental force has its own corresponding boson – the strong force is carried by the “gluon”, the electromagnetic force is carried by the “photon”, and the “W and Z bosons” are responsible for the weak force. Although not yet found, the “graviton” should be the corresponding force-carrying particle of gravity.
- The W boson is an elementary particle involved in radioactive decay and nuclear fusion.
- There are four fundamental forces in the universe; one of them is the weak nuclear force: it’s involved in nuclear fusion reactions and for radioactive decay.
- This force is mediated by two particles: the two W bosons and the Z boson. When two other particles exchange the W and/or Z bosons, they’re said to be acted on by the weak nuclear force.
What’s in the news?
- A new analysis of data collected at an experiment in the US before 2011 has revealed the mass of the W boson to be higher than expected according to theory.
- The new measurement disagrees with the Standard Model of particle physics, which describes the properties and behaviour of elementary particles.
- According to a new measurement, the mass of W bosons appears to be higher than that predicted by the Standard Model.
- There’s a framework of rules that describes how the elementary particles of our universe look and behave that physicists have spent decades putting together, called the Standard Model.
- The Standard Model is famously broken but physicists don’t know how. The Model can’t explain gravity and dark matter. It also can’t explain why the Higgs boson is so heavy, why the universe has more matter than antimatter, why gravity is so weak or why the size of the proton is what it is.
- And now there’s new evidence that it’s wrong about the mass of one particle.
- So when a Standard Model prediction is found to be wrong in an experiment, physicists can study the experiment more closely to understand where the value might have deviated. These deviations are broadly called ‘new physics’: they’re what physicists can use to fix the Standard Model.