POSSIBLE LINK BETWEEN THE CHANGING FINE-STRUCTURE CONSTANT AND THE ACCELERATING UNIVERSE VIA SCALAR-TENSOR THEORY

2002 ◽  
Vol 11 (07) ◽  
pp. 1137-1147 ◽  
Author(s):  
YASUNORI FUJII
Keyword(s):  
Fine Structure ◽  
Upper Bound ◽  
Structure Constant ◽  
Fine Structure Constant ◽  
Time Variability ◽  
Accelerating Universe ◽  
Scalar Tensor Theory ◽  
Tensor Theory ◽  
Acceleration Of The Universe ◽  
The Universe

In 1976, Shlyakhter showed that the Sm data from Oklo results in the upper bound on the time-variability of the fine-structure constant: [Formula: see text], which has ever been the most stringent bound. Since the details have never been published, however, we recently re-analyzed the latest data according to Shlyakhter's recipe. We nearly re-confirmed his results. To be more precise, however, the Sm data gives either an upper-bound or an evidence for a changing [Formula: see text]. A remark is made to a similar re-analysis due to Damour and Dyson. We also compare our result with a recent "evidence" due to Webb et al, obtained from distant QSO's. We point out a possible connection between this time-dependence and the behavior of a scalar field supposed to be responsible for the acceleration of the universe, also revealed recently.

scholarly journals Accelerating universe and the time-dependent fine-structure constant

2009 ◽  
Vol 5 (H15) ◽  
pp. 302-302
Author(s):  
Yasunori Fujii
Keyword(s):  
Fine Structure ◽  
Scalar Field ◽  
Structure Constant ◽  
Theoretical Background ◽  
Point Of View ◽  
Fine Structure Constant ◽  
Time Variability ◽  
Accelerating Universe ◽  
Tensor Theory ◽  
The Right

I start with assuming a gravitational scalar field as the dark-energy supposed to be responsible for the accelerating universe. Also from the point of view of unification, a scalar field implies a time-variability of certain “constants” in Nature. In this context I once derived a relation for the time-variability of the fine-structure constant α: Δα/α =ζ Ƶ(α/π) Δσ, where ζ and Ƶ are the constants of the order one, while σ on the right-hand side is the scalar field in action in the accelerating universe. I use the reduced Planckian units with c=ℏ =MP(=(8π G)−1/2)=1. I then compared the dynamics of the accelerating universe, on one hand, and Δα/α derived from the analyses of QSO absorption lines, Oklo phenomenon, also different atomic clocks in the laboratories, on the other hand. I am here going to discuss the theoretical background of the relation, based on the scalar-tensor theory invented first by Jordan in 1955.

scholarly journals THE VARIATION OF THE GRAVITATIONAL CONSTANT INFERRED FROM THE HUBBLE DIAGRAM OF TYPE Ia SUPERNOVAE

2006 ◽  
Vol 15 (08) ◽  
pp. 1163-1174 ◽  
Author(s):  
ENRIQUE GARCIA-BERRO ◽  
YURI KUBYSHIN ◽  
PABLO LOREN-AGUILAR ◽  
JORDI ISERN
Keyword(s):  
Fine Structure ◽  
Gravitational Constant ◽  
Structure Constant ◽  
Fine Structure Constant ◽  
Type Ia Supernovae ◽  
Scalar Tensor Theory ◽  
Hubble Diagram ◽  
Tensor Theory ◽  
Type Ia ◽  
Ia Supernovae

We consider a cosmological model with a variable gravitational constant, G, based on a scalar–tensor theory. Using the recent observational data for the Hubble diagram of type Ia supernovae (SNeIa), we find a phenomenological expression describing the variation of G. The corresponding variation of the fine structure constant α within multidimensional theories is also computed and is shown not to support known constraints on Δα/α.

scholarly journals New Limit on Space-Time Variations in the Proton-to-Electron Mass Ratio from Analysis of Quasar J110325-264515 Spectra

Symmetry ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 344
Author(s):  
T. D. Le
Keyword(s):  
Fine Structure ◽  
Structure Constant ◽  
Space Time ◽  
Fine Structure Constant ◽  
Electron Mass ◽  
Mass Ratio ◽  
Quasar Spectra ◽  
Time Variations ◽  
Using Data ◽  
The Universe

Astrophysical tests of current values for dimensionless constants known on Earth, such as the fine-structure constant, α , and proton-to-electron mass ratio, μ = m p / m e , are communicated using data from high-resolution quasar spectra in different regions or epochs of the universe. The symmetry wavelengths of [Fe II] lines from redshifted quasar spectra of J110325-264515 and their corresponding values in the laboratory were combined to find a new limit on space-time variations in the proton-to-electron mass ratio, ∆ μ / μ = ( 0.096 ± 0.182 ) × 10 − 7 . The results show how the indicated astrophysical observations can further improve the accuracy and space-time variations of physics constants.

scholarly journals Four direct measurements of the fine-structure constant 13 billion years ago

2020 ◽  
Vol 6 (17) ◽  
pp. eaay9672 ◽  
Author(s):  
Michael R. Wilczynska ◽  
John K. Webb ◽  
Matthew Bainbridge ◽  
John D. Barrow ◽  
Sarah E. I. Bosman ◽  
...  
Keyword(s):  
Fine Structure ◽  
Temporal Change ◽  
Structure Constant ◽  
Fine Structure Constant ◽  
Analysis Method ◽  
Weighted Mean ◽  
Near Ir ◽  
Very Large Telescope ◽  
Direct Measurements ◽  
The Universe

Observations of the redshift z = 7.085 quasar J1120+0641 are used to search for variations of the fine structure constant, a, over the redshift range 5:5 to 7:1. Observations at z = 7:1 probe the physics of the universe at only 0.8 billion years old. These are the most distant direct measurements of a to date and the first measurements using a near-IR spectrograph. A new AI analysis method is employed. Four measurements from the x-shooter spectrograph on the Very Large Telescope (VLT) constrain changes in a relative to the terrestrial value (α0). The weighted mean electromagnetic force in this location in the universe deviates from the terrestrial value by Δα/α = (αz − α0)/α0 = (−2:18 ± 7:27) × 10−5, consistent with no temporal change. Combining these measurements with existing data, we find a spatial variation is preferred over a no-variation model at the 3:9σ level.

scholarly journals Variation of the fundamental constants over the cosmological time: veracity of Dirac’s intriguing hypothesis

2016 ◽  
Vol 94 (1) ◽  
pp. 89-94 ◽  
Author(s):  
Cláudio Nassif ◽  
A.C. Amaro de Faria
Keyword(s):  
Fine Structure ◽  
Early Universe ◽  
Early Period ◽  
Planck Scale ◽  
Structure Constant ◽  
Energy Scale ◽  
Fine Structure Constant ◽  
Cosmological Time ◽  
Age Of The Universe ◽  
The Universe

We investigate how the universal constants, including the fine structure constant, have varied since the early universe close to the Planck energy scale (EP ∼ 1019 GeV) and, thus, how they have evolved over the cosmological time related to the temperature of the expanding universe. According to a previous paper (Nassif and Amaro de Faria, Jr. Phys. Rev. D, 86, 027703 (2012). doi:10.1103/PhysRevD.86.027703), we have shown that the speed of light was much higher close to the Planck scale. In the present work, we will go further, first by showing that both the Planck constant and the electron charge were also too large in the early universe. However, we conclude that the fine structure constant (α ≅ 1/137) has remained invariant with the age and temperature of the universe, which is in agreement with laboratory tests and some observational data. Furthermore, we will obtain the divergence of the electron (or proton) mass and also the gravitational constant (G) at the Planck scale. Thus, we will be able to verify the veracity of Dirac’s belief about the existence of “coincidences” between dimensionless ratios of subatomic and cosmological quantities, leading to a variation of G with time, that is, the ratio of the electrostatic to gravitational forces between an electron and a proton (∼1041) is roughly equal to the age of the universe divided by an elementary time constant, so that the strength of gravity, as determined by G, must vary inversely with time in the approximation of lower temperature or for times very far from the early period, to compensate for the time-variation of the Hubble parameter (H ∼ t−1). In short, we will show the validity of Dirac’s hypothesis only for times very far from the early period or T ≪ TP (∼1032 K).

Δα/α FROM QSO ABSORPTION LINES DRIVEN BY AN OSCILLATING SCALAR FIELD

2005 ◽  
Vol 14 (03n04) ◽  
pp. 677-685 ◽  
Author(s):  
YASUNORI FUJII ◽  
SHUNTARO MIZUNO
Keyword(s):  
Fine Structure ◽  
Scalar Field ◽  
Structure Constant ◽  
Oscillatory Behavior ◽  
Absorption Lines ◽  
Fine Structure Constant ◽  
Time Variability ◽  
The Past

The new result on the QSO absorption lines from the VLT–UVES sample is compared with the past reports on the time-variability of the fine-structure "constant" derived from the Keck/HIRES observation, on the basis of an oscillatory behavior of the scalar field supposed to be responsible for the cosmological acceleration.

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