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Murphy, Michael T.; Webb, John R.; Flambaum, V. V.; Curran, S. J.

doi:10.1023/a:1022570532369

Cited by 78 publications

(139 citation statements)

References 10 publications

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“…The result of this calculation (linear in the scaling parameter λ) is equivalent to the RPA. The next line ( Σ (2) ) includes second-order correlation corrections by means of many-body perturbation theory. Since we use "dressed" basis states (states calculated in a potential given by the Eq.…”

Section: Methods Of Calculationsmentioning

confidence: 99%

“…Details of the use ofΣ in atomic calculations can be found elsewhere [10]. The line labeled BO(Σ (2) ) presents results obtained by including the operatorΣ (2) in the Hartree-Fock equations for the valence electron and calculating Brueckner orbitals (BO) and the corresponding energies. These results differ from those in the previous line by higher-order contributions inΣ (Σ 2 ,Σ 3 , etc.).…”

Section: Methods Of Calculationsmentioning

confidence: 99%

“…They use an approximation very similar to that listed on line Σ (2) . Naturally, the results are also very close.…”

Section: Methods Of Calculationsmentioning

confidence: 99%

“…The first is perturbation theory [22] and the second is a finite-field approach in which only the second-order correlation operatorΣ (2) is used. In the perturbation theory calculation, we express the SMS operator P = i<j p i · p j as a sum of a normally ordered one-particle operator S and normally ordered two-particle operator T .…”

Section: B Specific Mass Shiftmentioning

confidence: 99%

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Calculation of isotope shifts for cesium and francium

2005

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We perform ab initio calculations of isotope shifts for isotopes of cesium (from A=123 to A=137) and francium (from A=207 to A=228). These calculations start from the relativistic Hartree-Fock method and make use of several techniques to include correlations. The field (volume) isotope shift is calculated by means of an all-order correlation potential method and within the singlesdoubles partial triples linearized coupled-cluster approach. Many-body perturbation theory in two different formulations is used to calculate the specific mass shift. We discuss the strong points and shortcomings of the different approaches and implications for parity nonconservation in atoms. Changes in nuclear charge radii are found by comparing the present calculations with experiment.

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Section: Methods Of Calculationsmentioning

confidence: 99%

Section: Methods Of Calculationsmentioning

confidence: 99%

“…They use an approximation very similar to that listed on line Σ (2) . Naturally, the results are also very close.…”

Section: Methods Of Calculationsmentioning

confidence: 99%

Section: B Specific Mass Shiftmentioning

confidence: 99%

See 2 more Smart Citations

Calculation of isotope shifts for cesium and francium

2005

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“…It looks as if the observational evidence for a redshift dependence in the fine structure parameter α is here to stay [36,37,38]. No such direct prediction graces the inflationary literature.…”

Section: Discussionmentioning

confidence: 97%

Comments on “Note on varying speed of light theories”

Magueijo

Moffat

2007

Gen Relativ Gravit

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Science with a 16 m VLT: The Case for Variability of Fundamental Constants

Molaro¹

Astrophysics and Space Science Proceedings

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Only astronomical observations can effectively probe in space-time the variability of the physical dimensionless constants such as the fine structure constant α and proton-to-electron mass ratio, µ, which are related to fundamental forces of nature. Several theories beyond the Standard Model (SM) allow fundamental constants to vary, but they cannot make quantitative predictions so that only laboratory experiments and astronomical observations can show if this is the case or set the allowed bounds. At the moment of writing there are claims for a variability of both α and µ at 5 and 4 σ of C.L., respectively, although for α they are contrasted by null results. The observations are challenging and a new spectrograph such as ESPRESSO at the combined incoherent focus of 4 VLT units (a potential 16 m equivalent telescope) will allow for a significant improvement in the precision measurement clearing up the controversy. If the variations will be confirmed, the implications are far reaching, revealing new physics beyond the SM and pointing a direction for GUTs theories. A most exciting possibility is that a variation of α is induced by quintessence through its coupling with the electromagnetic field. If this is the case an accurate measurement of the variability could provide a way for reconstructing the equation of state of Dark Energy [1]. IntroductionThe Standard Model (SM) of particle physics needs 26 dimensionless physical constants for the description of the natural world ([18]), of these few are directly related to the strength of fundamental forces. Among them the fine structure constant (α = e 2 /(hc)) and the proton-to-electron mass ratio, (µ = m p /m e ) are of particular interest for us since they can be measured accurately by astronomical observations of intervening absorption systems towards distant QSOs. The fine structure constant α is related to the strength

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Untitled

Cited by 78 publications

References 10 publications

Calculation of isotope shifts for cesium and francium

Calculation of isotope shifts for cesium and francium

Comments on “Note on varying speed of light theories”

Science with a 16 m VLT: The Case for Variability of Fundamental Constants

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