Explanation about the Higgs boson and Higgs field, based on http://www.youtube.com/watch?v=JY_F606E268

1. The Higgs boson
and Higgs field
slidecast for CLIL
Veerle De Cock
February 2014

2. Introduction
• film fragment about the Higgs boson
and Higgs field, by DrPhysicsA on a
YouTube channel, 27th of February
2012
• topic of the new curriculum of physics
in 2014-2015
• very up-to-date topic

3. • at the time the film fragment was
uploaded on YouTube, the Higgs
boson and Higgs field were predicted
but had not yet been found
• on 4 July 2012 Cern communicated
the detection of the Higgs particle

4. Fields: temperature
field
• measure with a thermometer the
temperature at every single point in a
room
• make a list of all this separate
temperatures
• this list represents the temperature
field
• the field causes an ice cube that is
introduced in it, to melt

5. Fields: electric field
• install an electric field between two
opposite charged plates
• put an electron in it: the electron starts
to move by the interaction with the
electric field
• put a neutron in it: the electric field
has no effect

6. The standard model of
particles
•
source: sbhep-nt.physics.sunysb.edu
• 6 quarks, 6 leptons and
4 bosons
• some have mass, some don’t
• mass is expressed in terms of
energy  E=mc²
• in 2012: Higgs boson!
• note: the standard model also acknowledges
four forces or fundamental interactions:
gravitational, electromagnetic, strong and weak

7. Research and prediction
by F. Englert, R. Brout and
P. Higgs in 1964
• what causes elementary particles to
have mass?
• why do some have mass and some
don’t?
• prediction: there must be a field
constructed of an elementary particle
that could give mass to elementary
particles

8. Mass
• not: our mass or the mass of a proton
or electron!
• proton: 2 up quarks and 1 down quark
• together 8 MeV  proton 938 MeV
• high amount of energy by constraining
the quarks inside the proton
• energy is manifested in mass (E=mc²)

9. • particles without mass such as a
photon must travel at the speed of
light ( c ):
– E=γmc² (special relativity)
– γ is the Lorentz factor
– a photon has energy (E=hf)
– this is only possible if v equals c:
– this is mathematically undefined but
not 0!

10. Theory of the Higgs field
• this field exists in all points of the
universe
• a scalar field in three dimensions
• at the bottom: lowest energy
• particles without mass circle at
the bottom
• particles with mass gain their
mass as a result of oscillation
•
source: sbhep-nt.physics.sunysb.edu

11. • particles without mass don’t interact
with the field, particles with mass do
• conceptual presentation of the field:
– a room half filled with water
– a person is impeded and slows down
when trying to move through the room
a particle acquires mass by
interacting with the Higgs field
– a fish isn’t impeded at all 
a particle without mass, e.g. a photon
encounters no interaction with the
Higgs field

12. The Higgs boson (or
BEH boson)
• a field is mediated by a boson
• the standard forces each have a
specific type of messenger particle to
exchange information
• e.g. electromagnetic interactions 
communication by a photon
• the Higgs field is mediated by the
Higgs boson

13. • the Higgs boson can’t be
photographed or detected directly
• the Higgs boson was predicted to
have a hefty mass of 125-126 GeV
• the Higgs boson was predicted to
decay immediately into other particles
(bottom quarks and W bosons)
• these hypotheses have been proved
by experiments with LHC in
Cern, when 2 protons at very close
the speed of light collided and as a
result all kind of particles were formed

14. Listen also to http://ed.ted.com/lessons/the-higgs-field-explained-don-lincoln