Notes
Slide Show
Outline
1
Variation of
Fundamental Constants from Big Bang to Atomic Clocks

  • V.V. Flambaum
  • School of Physics, UNSW, Sydney, Australia
  • Co-authors:
  •  Atomic calculations V.Dzuba,M.Kozlov,E.Angstmann,J.Berengut,M.Marchenko,Cheng Chin,S.Karshenboim,A.Nevsky
  • Nuclear and QCD calculations  E.Shuryak,V.Dmitriev,D.Leinweber,A.Thomas,R.Young,A.Hoell,
  • P.Jaikumar,C.Roberts,S.Wright,A.Tedesco,W.Wiringa
  • Cosmology J.Barrow
  • Quasar data analysis J.Webb,M.Murphy,M.Drinkwater,W.Walsh,P.Tsanavaris,S.Curran
  • Quasar observations C.Churchill,J.Prochazka,A.Wolfe, thanks to W.Sargent,R.Simcoe
2
Motivation
  • Extra space dimensions (Kaluza-Klein, Superstring and M-theories). Extra space dimensions is a common feature of theories unifying gravity with other interactions. Any change in size of these dimensions would manifest itself in the 3D world as variation of fundamental constants.
  • Scalar fields . Fundamental constants  depend on scalar fields which vary in space and time (variable vacuum dielectric constant  e0 ). May be related to “dark energy” and accelerated expansion of the Universe..
  • “ Fine tuning” of fundamental constants is needed for humans  to exist. Example: low-energy resonance in production of carbon from helium in stars (He+He+He=C). Slightly different coupling constants — no resonance –- no life.
  •           Variation of coupling constants in space provide natural explanation of the “fine tuning”: we appeared in area of the Universe where values of fundamental constants are suitable for our existence.
3
Search for variation of fundamental constants
4
Which Constants?
  •    Since variation of dimensional constants cannot be distinguished from variation of units, it only makes sense to consider variation of dimensionless constants.
  • Fine structure constant a=e2/hc=1/137.036
  • Electron or quark mass/QCD strong interaction scale,  me,q/LQCD
  •       a strong  (r)=const/ln(r LQCD /ch)


5
 
6
 
7
Quasar absorption spectra
8
Quasar absorption spectra
9
"Use atomic calculations to find..."
  • Use atomic calculations to find w(a).


  • For a close to a0    w = w0 + q(a2/a02-1)


  • q is found by varying a in computer codes:


  • q = dw/dx = [w(0.1)-w(-0.1)]/0.2,  x=a2/a02-1
10
Methods of Atomic Calculations
11
Fine structure anomalies and level crossing
12
Problem: level pseudo crossing
  • Values of  q=dE/da2  are sensitive to the position of level crossing
13
Results of calculations (in cm-1)
14
 
15
 
16
 
17
Results of the analysis
  • Murphy et al, 2003: Keck telescope, 143 systems, 23 lines,  0.2<z<4.2
  •  Da/a=-0.543(116) x 10-5


18
 
19
Spatial variation (C.L.Steinhardt)
  • 10 5  Da/a
  • Murphy et al
  • North hemisphere           -0.66(12)
  • South (close to North)     -0.36(19)
  •   Strianand et al (South)     -0.06(06)
20
Variation of strong interaction
  • Grand unification models (Marciano; Calmet,
  • Fritzch;Langecker,Segre Strasser;Dent)
  • D(m/LQCD)/(m/LQCD)=35Da/a
  • Proton mass Mp=3LQCD , measure me/Mp
  • Nuclear magnetic moments m=g eh/4Mpc
  •         g=g(mq/ LQCD)
  • 3. Nuclear energy levels
21
Dependence on quark mass
  • Dimensionless parameter is mq/LQCD . It is convenient to assume LQCD =const, i.e. measure mq in units of LQCD
  • mp  is proportional to (mqLQCD)1/2   Dmp/mp=0.5Dmq/mq
  • Other meson and nucleon masses remains finite for mq=0.      Dm/m=K Dmq/mq
  • Coefficients K are calculated for p,n,r,w,s.


22
Nuclear magnetic moments depends on p-meson mass mp
23
"Nucleon magnetic moment"
  • Nucleon magnetic moment
24
Measurements me / Mp  or me / LQCD
  • Tsanavaris,Webb,Murphy,Flambaum,
  • Curran PRL 2005
  • Hyperfine H/optical , 8 quasar absorption systems with Mg,Ca,Mn,C,Si,Zn,Cr,Fe,Ni
  • Measured X=a2 gp me / Mp
  • DX/X=1.17(1.01)10-5    No variation
  •  Reinhold,Bunnin,Hollenstein,Ivanchik,
  • Petitjean PRL 2006 , H2     molecule, 2 systems
  • D(me / Mp )/ (me / Mp)=-2.4(0.6)10-5    Variation 4 s !
  • Systematics or space-time variation?


25
 
26
 
27
 
28
 
29
Oklo natural nuclear reactor
  • n+Sm capture cross section is dominated by
  • Er =0.1 eV resonance
  • Shlyakhter;Damour,Dyson;Fujii et al
  • Limits on variation of alpha


  • Flambaum, Shuryak PRD 2003
  •  DEr = 170 MeV DX/X + 1 MeV Da/a
  • X=ms/ LQCD ,   enhancement 170 MeV/0.1 eV=1.7x109


  • Lamoreax,Torgerson PRD(2004) DEr =-0.58(5) eV


  • DX/X=-0.34(3) 10-9   two billion years ago


30
Atomic clocks
  • Cesium primary frequency standard:
31
Optical frequency standards:
32
Atomic clocks:
  •    Comparing rates of different clocks over long period of time can be used to study time variation of fundamental constants!
33
Advantages:
  • Very narrow lines, high accuracy of measurements.


  • Flexibility to choose lines with larger sensitivity to variation of fundamental constants.


  • Simple interpretation (local time variation).
34
Calculations to link change of frequency to change of fundamental constants:
  • Microwave transitions:  hyperfine frequency is sensitive to nuclear magnetic moments (suggested by Karshenboim)


  • We performed atomic, nuclear and QCD calculations of powers k ,b for H,D,Rb,Cd+,Cs,Yb+,Hg+
  • V=C(Ry)(me/Mp)a2+k  (mq/LQCD)b ,  Dw/w=DV/V
35
Results for variation of fundamental constants
36
Dysprosium miracle
  •  Dy:  4f105d6s   E=19797.96… cm-1 ,  q=    6000 cm-1
  •          4f95d26s   E=19797.96… cm-1 ,  q= -23000 cm-1
  •  Interval Dw = 10-4 cm-1




  • Enhancement factor  K = 108 (!),  i.e. Dw/w0 = 108 Da/a
37
Molecular clocks
  • Cancellations between rotational and hyperfine intervals in very narrow microwave transitions in
  •  LaS, LaO, LuS,LuO, etc.
  • w0   =Erotational -E hyperfine= E hyperfine /100-1000
  • Enhancement factor  K = 102 -103,
  •  Dw/w0 = K Da/a
38
Nuclear clocks
(suggested by Peik,Tamm 2003)
  • Very narrow UV transition between first excited and ground state in  229 Th nucleus
  • Energy 3-5 eV, width 10-4   Hz


  • Nuclear/QCD calculation: Enhancement 105 -106,
  •  Dw/w0 =  105   (4 Da/a + DXq/Xq-10DXs/Xs )
  • Xq=mq/ LQCD ,   Xs=ms/ LQCD


  • 235 U  energy 76 eV, width 6 10-4   Hz


39
Ultracold atomic and molecular collisions (in Bose condensate). Cheng Chin, Flambaum PRL 2006
  • Enhancement near Feshbach resonance.
  • Variation of scattering length
  • a/a=K D X/X  ,  K=102 – 1012
  •   X=me/Mp
40
Conclusions
  • Quasar data: MM method provided sensitivity increase 100 times. Anchors, positive and negative shifters-control of systematics. Keck- variation of  a, VLT-no variation. Undiscovered systematics or spatial variation.
  • me /Mp  : hyperfine H/optical – no variation, H2  - variation 4 s . Undiscovered systematics or space-time variation.
  • Big Bang Nucleosynthesis: may be interpreted as variation of ms/ LQCD   ?
  • Oklo: variation of ms/ LQCD   ?
  •  Atomic clocks: present time variation of a , ms/ LQCD
  • Transitions between narrow close levels in atoms, molecules and nuclei – huge enhancement!
41
 
42
Publications:
  • V. A. Dzuba, V. V. Flambaum, J, K. Webb, PRL 82, 888 (1999).
  • V. A. Dzuba, V. V. Flambaum, J, K. Webb, PRA 59, 230 (1999).
  • V. A. Dzuba, V. V. Flambaum,  PRA 61, 034502 (2000).
  • V. A. Dzuba, V. V. Flambaum, M. T. Murphy, J, K. Webb, LNP 570, 564 (2001).
  • J. K. Webb et al , PRL 87, 091301 (2001).
  • V. A. Dzuba, V. V. Flambaum, M. T. Murphy, J, K. Webb, PRA 63, 042509 (2001).
  • M. M. Murphy et al, MNRAS, 327, 1208 (2001).
  • V. A. Dzuba et al, PRA, 66, 022501 (2002).
  • V. A. Dzuba, V. V. Flambaum, M. V. Marchenko, PRA 68, 022506 (2003).
  • E. J. Angstmann, V. A. Dzuba, V. V. Flambaum, PRA 70, 014102 (2004).
  • J. C. Berengat et al, PRA 70, 064101 (2004).
  • M. M. Murphy et al, LNP, 648, 131 (2004).
  • V. A. Dzuba, PRA, 71, 032512 (2005).
  • V. A. Dzuba, V. V. Flambaum, PRA, 71, 052509 (2005).
  • V. A. Dzuba, V. V. Flambaum, PRA, 72, 052514 (2005).
  • V. A. Dzuba, PRA, 71, 062501 (2005).
  • S. G. Karshenboim et al, physics/0511180.
43
 
44
 
45
 
46
 
47
 
48
 
49
 
50
 
51
 
52
 
53
 
54
 
55
 
56
 
57
Alkali Doublet Method
(Varshalovich, Potekhin, Ivanchik, et al)
  • Fine structure interval


  • DFS = E(p3/2) - E(p1/2) = A(Za)2


  • If DZ is observed at red shift Z and D0 is FS measured on Earth then
58
 
59
 
60
 
61
 
62
 
63
 
64
 
65
 
66
 
67
 
68
 
69
 
70
 
71
 
72
 
73
 
74
 
75
 
76
 
77
 
78
 
79
 
80
 
81
 
82
Text
83
Many Multiplet Method
(Flambaum, Webb, Murphy, et al)
84
Atoms of interest
85
Fine structure unomalies and level crossing
86
Fine structure unomalies and level crossing
87
Implications to study of a variation
  • Not every fine structure interval can be used in the analysis based on formula DE=A(Za)2  (not good!).
  • Strong enhancement is possible (good, but for atomic clocks only).
  • Level crossing may lead to instability of calculations (bad!).
88
Problem: level pseudo crossing
89
Pb II: g-factors don’t help
  • Two 3D3/2 states are strongly mixed, but g-factors do not depend on mixing.
90
Microwave transitions