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The Standard ModelThe Standard Modeland and
BeyondBeyondHarrison B. Prosper
6 July, 2010
Fermilab Summer Lecture Series
2
Where Do We Come From? What Are We?
Where Are We Going? Paul Gauguin
(1897) Museum of Fine Arts, Boston
The Standard ModelThe Standard Model
4
What is the Standard Model?What is the Standard Model?
The Standard Model (SM) is a quantum field theoryquantum field theory
that describes the excitationsexcitations of quantum fields quantum fields in spacetime
We interpret these excitations as particlesparticles
Matter
Up quark Down quark
e
Electron Antielectron Neutrino
νe
u d
ForcesForces
Strong Force 11 (Gluons)(Gluons)Binds protons and neutrons to form nuclei
Electromagnetic Force 1010-2-2 (Photon)(Photon)Binds electrons and nuclei to form atoms
Weak Force 1010-5-5 (W & Z Bosons)(W & Z Bosons)Causes radioactivity
Gravitational Force 1010-39-39 (Graviton)(Graviton)Binds matter on large scales
Discovery, Electron – 18971897
J.J Thomson
Discovery, Top Quark – 19951995 CDF & DØ
A Century of High Energy PhysicsA Century of High Energy Physics
1897 – ELECTRON discovery Thomson1909 – PROTON discovery Rutherford
1928 – ANTIMATTER theory Dirac1930 – NEUTRINO theory Pauli1932 – NEUTRON discovery Chadwick1932 – POSITRON discovery Anderson1935 – EXCHANGE theory Yukawa
1948 – QED theory Feynman,…1961 - ELECTROWEAK theory Glashow 1964 – QUARK theory Gell-Man, Zweig1964 – HIGGS theory Higgs, Englert,…1967 – ELECTROWEAK theory Weinberg, Salam,…
A Century of Particle PhysicsA Century of Particle Physics
1971 – 73 QCD theory ‘t Hooft, Veltman, Gell-Man, Frisch,
Gross, Wilzcek, Politzer
1974 – CHARM discovery Ting, Richter1977 – BOTTOM discovery Lederman1979 – GLUON1979 – GLUON discovery TASSO, JADEJADE,
MARK-J, PLUTO1983 – W & Z discovery Rubbia/UA1, UA2
1995 – TOP1995 – TOP discovery DDØØ & CDF
A Century of Particle PhysicsA Century of Particle Physics
N
Neutron
Proton
P
e
Electron νe
Anti-electron neutrino
Fermi’s 1934 theory of beta-decay
Enrico Fermi 1901 - 1954
1934 – Theory of Beta Decay1934 – Theory of Beta Decay
11
1935 – Particle Exchange Theory1935 – Particle Exchange Theory
Hideki Yukawa (1935) showed that the potential energypotential energy between two particles has the form
mm is the mass of the particleparticle exchanged between the them
RR = = hc hc / mcmc2 is the range of the force
Hideki Yukawa 1907 - 1981
12
1948 – Quantum Electrodynamics1948 – Quantum Electrodynamics
Feynman invented
a systematic way to calculate the force between electrically charged particles, based on Yukawa’s idea of particle exchange
g g
y y
f
Richard P. Feynman 1918 - 1988
Feynman Diagram
N
Neutron
Proton
P
e
Electron
The Weak ForceThe Weak Force
Given the success of QED it was natural to try to create an analogous theory of the weak force
νe
Anti-electron neutrino
N
Neutron
Proton
P
e
Electron
The Weak ForceThe Weak Force
Given the success of QED it was natural to try to create an analogous theory of the weak force
νe
Anti-electron neutrino
W-
15
1961 – The Electroweak Theory1961 – The Electroweak Theory
Glashow Theory + Higgs Theory Electroweak Theory
(1967)
Steven Weinberg Abdus Salam
Sheldon Glashow (1961)
u d e
s μ
νe
νμ
Quarks Leptons+2/3 -1/3 -1 0
1964 – The Quark Model1964 – The Quark Model
Gell-Man and Zweig
17
The Quark ModelThe Quark Model
u ud
d du
Proton Neutron
uuu
Delta++
The Delta++ puzzle
+1 0 +2
u
s
d e νe
Quarks Leptons+2/3 -1/3 -1 0
The Quark ModelThe Quark Model
u u u d d d
s s s
One possible solution: color charge color charge
(Greenberg, Frizsch, Gell-Man, Leutwyler)
μ νμ
u uu
d ud
u du
19
The Quark ModelThe Quark Model
Proton Neutron Delta++
Problem solved !
+1 0 +2
20
1971 – The Theories Make Sense!1971 – The Theories Make Sense!
Martinus Veltman Gerard 't Hooft
1971 - Proved that theories of the sort created by Glashow, Weinberg and Salam are consistent
The Strong ForceThe Strong Force
Proton
u
u d
u
u d
u
u d
gg
g
u
u d
u
u d
u
u d
1972-73 Quantum Chromodynamics (QCD)
Gross
Politzer
Wilczek
22
Discovery of the GluonDiscovery of the Gluon
gqqee
1979 TASSOMARK-JJADEJADEPLUTO
DESYHamburg,Germany
23
Discovery of Top the QuarkDiscovery of Top the Quark
1995CDFDØDØ
Fermilab
u u u d d d e
b b b τ
c c c s s s μ
g g g g g g g g
γ Z W+
νe
ντ
νμ
Quarks Leptons+2/3 -1/3 -1 0
I
II
III
Bos
ons
Fer
mio
ns
The Standard ModelThe Standard Model
H
t t t
W-
……And BeyondAnd Beyond
26
SupersymmetrySupersymmetry
CompositenessCompositeness
StringsStrings
MultiverseMultiverse
TechnicolorTechnicolor
Extra DimensionsExtra Dimensions
Brane WorldsBrane Worlds
27
PuzzlesPuzzles
The Identity PuzzleWhat makes a top quark a top quark, an electron an
electron, and a neutrino a neutrino? (Chris Quigg, 2007)
The Mass PuzzleWhat is the origin of the mass of fundamental
particles?
The Matter PuzzleWhy is there overwhelmingly more matter than
antimatter?
28
The Just-So Puzzle
What determines the values of the Standard Model parameters? Or, are we special?
The Gravity Puzzle
Why strongstrong: emem: weakweak: gravitygravity = 11: : 1010-2-2: : 1010-5-5: 10: 10-39-39 ?
The Dark Matter PuzzleWhat is dark matter?
The Dark Energy Puzzle
Why is dark energy?
PuzzlesPuzzles
The Mass Puzzle
u d
u
Total mass 9.6 MeV
Total mass 938 MeV !!
m =Ec2
The Proton BasketThe Proton Basket2.3 MeV 5 MeV
2.3 MeV
The Mass Puzzle – A Solution?
B. Robson, “The Generation Model and the Origin of Mass”,Int. J. Mod. Phys. E18 (2009)
T T
V
T T
T
T
V
V
e+
V
V
VV
V
V
T
V
V T
T
V T
T
T
u d
ν ν
d u e−
The Just-So Puzzle
d u
d
NeutronProton
u d
u
2.3 MeV2.3 MeV5.0 MeV_______9.6 MeV
5.0 MeV5.0 MeV2.3 MeV_______12.3 MeV
938.3 MeV – 9.6 MeV928.7 MeV928.7 MeV
939.6 MeV–12.3 MeV927.3 MeV927.3 MeV
Are we special?
Life in the Multiverse
Alejandro JenkinsFlorida State University
Scientific AmericanJanuary 2010
33
The Gravity PuzzleThe Gravity Puzzle
1010-39-39
Gravity on the BraneGravity on the Brane
34
Isaac Newton(1687)
F =GmMr2
rg ⋅d
rA=4πGM—∫
Gauss’ Law
Our 3-D brane
Gravity in 3 + n DimensionsGravity in 3 + n Dimensions
35
F ~ Gn
mM
rn+2
Arkani-Hamed, Dimopoulos, Dvali
(1998)
rg ⋅d
rA=4πGM—∫
Gauss’ Law
Our 3-D brane
36
R
Gravity in 3 + n DimensionsGravity in 3 + n Dimensions
F ~ Gn
mM
rn+2
Suppose that gravity can propagate a distance R away from our 3-D brane world
37
When r >> R, the gravity force should look like Newton’s law of gravity
R
This yieldsthe relationGG = = GGn n / / RRnn
F ~Gn
Rn
⎛⎝⎜
⎞⎠⎟
mMr2
Gravity in 3 + n DimensionsGravity in 3 + n Dimensions
Searching for Branes at Fermilab!Searching for Branes at Fermilab!
38
G
p p
γ
One way: look for photon + unexplained amounts of missing momentum
39
The Era of the Large Hadron ColliderThe Era of the Large Hadron Collider
CERN
Geneva
40
The EndThe End
CERN