Professor Peter Kalmus

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Particles and the Universe
Professor Peter Kalmus
Physics Department
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10,000,000,000,000,000,000,000,000,000,000,000,000
,000,000,000,000,000,000,000
Supernova 1987A
Neutrino numbers Emitted 1058 Hit Earth
1029 Hit tank 1017 Interact 10
Energy release 1046 J
SN 1987A
Earth
SN 1046 J
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8 arc min
Large Magellanic Cloud Sanduleak - 69o 202
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LHC
History of the Universe
T/K

Energy
Tevatron
LEP

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10

1 TeV
Particle
Era
Era of

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1 GeV
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Astronomy
Nuclear
Primordial
Era
Soup
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1 MeV
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Atomic
Era
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1 keV
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10
1 eV
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Hot as Hell 445oC Boiling point of Brimstone
Sun forms
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1 meV
Time
m
ps ns
s ms s
1 day
1 year
Today
Time since Big Bang / s
10-12
10-6
100
1013
1018
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Primordial Soup
CERN style 100 GeV / particle
Ingredients 56 quarks 16 gluons 9 charged
leptons 9 W Z particles 5 neutrinos 2
photons 2 gravitons 1 Higgs bosons Recipe
by Rocky Kolb
Hot 3 x 1015K Condensed
Missing ingredients
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Inverse square law
Sun
v
Mo
a
Kepler, Newton T2 4 p2 a3 /G Mo v2 G Mo/a
(circular orbit)
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Galaxy rotation curve
Measured velocities from Doppler shifts
Expect from detected stars etc.
Hence there is more gravitationally attractive
material than has been detected ? Dark matter
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Explosion in empty space (forget about gravity)
Dark energy
After some time the fastest particles will be
furthest away
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• Plot distance against
• recession velocity for many galaxies
• Get straight line
• Big Bang

The Universe is like this !
Distance (Magnitude)
furthest galaxy highest recession velocity
Hubble Diagram
nearest galaxy
Recession velocity (Doppler Redshift z)
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But cannot ignore gravity which slows down the
flow
Hubble Diagram
Distance (Magnitude)
Expect this line to curve downwards for very
distant galaxies. Expansion would decelerate
Recession velocity (Doppler Redshift z)
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Hubble Diagram
(simplified)
Recent results show that expansion is
accelerating !
Distance (Magnitude)
Cosmic repulsion ! Dark energy
Recession velocity (Doppler Redshift z)
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Early 20th Century electron,
nucleus
1930s
electric force electromagnetism
Nucleus
Atom
bunch of grapes
10-10m
10-15m
town
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Neutrinos
Feel weak force predicted ? later discovered
100,000,000,000,000 per second pass
through each person from the Sun
Equal and opposite properties predicted ?
later discovered Annihilate with normal
particles Now used in PET scans
Antiparticles
Many new particles created in high energy
collisions
1950s, 1960s
Convert energy to mass. Einstein E mc2
gt 200 new elementary (?) particles
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Todays building blocks
proton u u d 2/3 2/3 -1/3 1 neutron u d
d 2/3 -1/3 -1/3 0
4 particles very simple multiply by 3
(generations) multiply by 2 (antiparticles)
First generation
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muon m- -1 m-neutrino nm 0
charm c 2/3 strange s -1/3
tau t- -1 t-neutrino nt
0
top t 2/3 bottom b -1/3
Recent news pentaquarks
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Earth, Moon, X Solar system X Antistars in
our Galaxy ? Other (anti-) galaxies ?
Anti-hydrogen made in lab Bulk antimatter ?
Where ? Difficult to detect
Signal ? e e - g g 0.511 MeV
g-ray line
g g g
Radiation pressure
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Constituents
How can we find internal structure?
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Quantum physics to the rescue
Particles have wave properties
See small objects ? small
wavelength ? high momentum
? high energy ?
large accelerator
Non-relativistic p m v mass x
velocity Relativistic p g m v g 1/ (1 -
v2/c2)1/2
To observe the smallest objects we need the
largest machines !
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Accelerator

Extract beam
RF cavities electric kick
Bending electro- magnet
Focusing electro- magnet
Vacuum ring
Injector
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Forces by exchange
Analogy only Useful mental picture ?
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Attraction
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of the fundamental forces of nature
Unification
Faraday, Maxwell
Newton
Electricity
Magnetism
Apples
Planets
Electro- magnetic
Gravity
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of the fundamental forces of nature
Unification
Faraday, Maxwell
Newton
Electricity
Magnetism
Apples
Planets
Electro- magnetic
Gravity
Weak
Strong
Salam, Weinberg, Glashow
Electroweak unified force
g, W , W -, Z 0 0 80 80 90 GeV
Do the W and Z particles really exist ?
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Collider
Inject anti- protons

RF cavities electric kick
Bending electro- magnet
Carlo Rubbia Antiprotons
Collide 2 beams Inside vacuum
Focusing electro- magnet
Simon van der Meer Stochastic cooling
Inject protons
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Carriers of Weak Force Found at CERN The W boson
the hypo
The Discovery of the W Boson The observation of
the W intermediate vector boson, the particle
that carries the weak nuclear force, is the most
outstanding achievement of the CERN laboratory in
Geneva and one of the most important advances in
physics of this century. It is the successful
conclusion of
carries the weak force which controls the
production of energy in the Sun and some
The Role of UK Scientists Twenty-five British
scientists played an important part in the
remarkable discovery of the W boson. They were
led by Professor J D Dowell of Birmingham
University, Professor P I P Kalmus of Queen Mary
College and Dr A Astbury of Rutherford Appleton
Laboratory. The W boson
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It is very encouraging that so many British
scientists were in the team that discovered the
W boson, and I would like to congratulate you
and your colleagues from Queen Mary College on
your success. I am sure that British physicists
will be among the first to unify all the four
basic forces
From THE PRIME MINISTER 10 Downing
Street To Professor P. I. P. Kalmus
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W and Z particles discovered
UA1 Collaboration at CERN Included following
members of Queen Mary
Results confirmed by another CERN
collaboration, and few years later at Fermilab
USA
Electroweak unification confirmed Natures
fundamental forces reduced from 4 to 3 Nobel
Prizes
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THE END
p.i.p.kalmus_at_qmul.ac.uk http//www.ph.qmul.ac.uk