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Folie 1

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28 constants of nature 24 constants mass parameters Grand unification relates the elm., strong and weak interactions. The time variation of alpha leads ... – PowerPoint PPT presentation

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Title: Folie 1


1
Time Variation

Fundamental Constants
and their
Harald Fritzsch LMU Munich
2
-
fundamental constants
the
problem of modern science
3
particle physics nuclear
atomic laser
solid state astro
cosmology
fundamental constants gt
4

gt chemistry, biology, ...
5
-
Fundamental constants
Standard Model
6
-
Standard Model
gauge theories
7
-
first gauge theory
QED
8
-
QED 2 fundamental constants
9
1964 gt
electroweak gauge theory
U(1) x SU(2)
10

gauge theory of the
Strong Interactions
11
-
M. Gell-Mann G. Zweig
M. Gell-Mann
G. Zweig
1964
quarks
12
-
(
)
u
(
)
p
d
n
s
electric charge
13
(No Transcript)
14
-
color
1971
qgt
q
q
q
SU(3,c)
15
-
- Hadrons -
white states
16
-
1971 - 1972
QCD
Fritzsch Gell-Mann
17
8 gluons
18
-
1973
Standard Model
SU(3) x SU(2) x U(1)
2 gt 28
19
problem
gt
28 fundamental constants
20
Newtons constant G
1
fine structure constant
1 coupling constant of strong interaction
1 coupling constant of weak interaction
1 mass of W boson
1 mass of Higgs boson
1 masses of 6 quarks and 6 leptons
12 flavor mixing of quarks
4 flavor mixing of
leptons 6
-
28
21
28
22
(22 related to fermion masses)
23
-
MeV
masses
100
10
1
24
-
Arnold Sommerfeld, 1916
fine-structure constant

25
-
electrodynamics relativity quantum theory
26
QED
27
partial screening

-


-
-
-
-
28
fine-structure constant gt
function of energy

29
-
LEP 1/127
30
-
nucleon mass
fundamental constant ?
gt QCD
31
-
quark masses gt 0
mass ltgt field energy
32
dimensional transmutation
33

nucleon mass ( quark masses gt 0
34

Experiments
250 MeV
mass ltgt confined field energy
35

real world
QCD u d s
QED
M (proton)
860 21 19 36 2
36

Standard Model
fundamental constants in our universe
universal
37

Are the fundamental constants functions of time
and space?
38
-
function of energy
39
-
? function of time?
40
  • About 1.8 billion years ago, in Gabon,
    Westafrika.
  • Natural Reactor, which operated about 100 million
    years.
  • High concentration of uranium
  • 3.7 U 235 at that time (today 0.72 )
  • Moderator water from river Oklo

Oklo Phenomen
41

discovery 1972
Natural reactor
( output 100 kw )
42

43
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44
Oklo zones
45
-
samarium
neutron capture
Sm(149) n gt Sm(150) photon
cross section about 80 kb
nuclear resonance E 0.0973 eV
46
-
change of resonance position less than 0.1 eV
in 2 billion years
constraint for fine-structure constant
( Dyson, Damour)
47
  • Change of alpha per year
  • must be less than
  • per year
  • (if no other parameters change)
  • gtconstraint questionable

-16
10
48
-
limits on time variation of constantes, related
to stable matter
fine-structure constant mass of electron QCD
scale quark masses
49

time variation of QCD scale
50

u / d - quarks
20 MeV of proton mass
51

unstable particles
mass of muon, tauon, c-quark, b-quark and t-quark
flavor mixing angles mass of weak boson
52
b-quarks
53
t-quark m 171.3 /- 2.3 MeV
54

1686
Newtons constant of gravity
55
1686
56
Dirac (1930)
Time Variation of Newtons constant G
57
-
excluded recently by satellite experiments -
NASA-
58
Time variation of natural constants?
Time Variation of alpha?
Observation of fine structure of atomic
levels Quasars 5-7 billion years back
59
Quasar absorption spectra
Light
earth
gas
quasar
60
Keck telescope Hawaii
61
Experiment at Keck telescope (Australia, England,
USA)
( Webb, Wolf, Flambaum...)
  • Fine structure of Fe, Ni, Mg, Sn, A -
  • Quasars, back to 11 bn years in time

62
-
N. Kanekar et al. (May 2010) arXiv1004.5383 same
result as Webb et al.
63
(No Transcript)
64
-
grand unification
SU(3)xSU(2)xU(1) gtSO(10)
( Fritzsch - Minkowski Georgi - 1975 )
65
SO(10)
SO(6) x SO(4)
_
SU(4) x SU(2,L) x SU(2,R)
SU(3) x SU(2,L) x U(1)
_
66
-
Grand Unification
3 coupling constants
electromagnetic, weak and strong interactions
reduced to two parameters
unification scale and unified coupling
67
SO(10)
Fermions in 16-plet
( incl. righthanded neutrinos )
68
-
Leptons and Quarks in SO(10)
SO(10)
69
Neutrinos have a mass
70
1/coupling constant
Grand Unification
energy

71
-
time change of
72
1/coupling constant
Grand Unification
energy

73
1/coupling constant
Grand Unification
energy

74
1/coupling constant
Grand Unification
energy

75
1/coupling constant
Grand Unification
energy

76
Calmet, Fritzsch Langacker, Segre
2002
no change of unification scale
77
Magnetic moments of atomic nuclei would
change accordingly, per year
78

change of unification scale
79
-
80

experiments
MPQ Munich
NIST Boulder
81
  • Time
  • measured by Cesium clocks
  • Hyperfine transition ? magnetic moment of the
    cesium nucleus.
  • Would be affected by time change of QCD scale

Cesium 9 192 631 770 Hz
(definition of time)
82
comparison
Cs- clock
hydrogen clock
difference 3 Cs oscillations per day
Experiment (T. Hänsch, MPQ)
83
T. Hänsch
84
MPQ-Experiment
  • 486 nm dye laser in hydrogen
  • spectrometer
  • Reference cesium clock Pharao LPTF Paris
  • Hydrogen 1s-2s transition
  • 2 466 061 413 187 127 (18) Hz

MPQ-experiment
85
(No Transcript)
86
-
result of Haensch
87
Expected in simple model about 10 times more
experiment
expected
gt excluded!
88
  • Simultaneous change
  • of the unified coupling constant and the
    unification scale?

89
1/coupling constant
Grand Unification
energy

90
  • Simultaneous change of unif. coupling and
  • unif. scale
  • Partial Cancellation of effect?
  • (expected in superstring models)

cancellation
91
(No Transcript)
92
-
Hänsch et al.
93
Reinhold et al., 2006
VLT Chile
94
  • Reinhold et al. PRL 96 (2006)
  • 2 quasars, 12 bn. years away
  • time variation of ratio
  • proton mass / electron mass

95
-
( if the electron mass is taken to be constant )
96
-
gt Hänsch
97
  • The masses of atomic nuclei will depend on time!

energy not strictly conserved
98
does alpha depend on space?
99
-
Webb et al, 2010
VLT and Keck
small space dependence of fine-structure constant
100
  • 28 constants of nature
  • 24 constants ? mass parameters
  • Grand unification relates the elm., strong
    and weak interactions.

Conclusions
101
The time variation of alpha leads to a time
variation of the QCD scale. The MPQ
Experiment rules out the simplest model. An
effect seems to be present, about a factor 10
less than naively expected, consistent with the
observed variation of the electron-proton mass
ratio.
102
Necessary Both unification scale and unified
coupling must change in time. (expected in
superstring models)
103
Perhaps all fundamental constants are not
constant, but functions of time?
gt cosmology?
104
Universe
gt Multiverse
105
Inflationary multiverse
106
Birth of Fundamental Constants
107
Fundamental constants
cosmic accidents?
108
(No Transcript)
109
cosmic accidents
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