Electromagnetic Fine Structure Constant Research Articles

The electromagnetic fine-structure constant in primordial nucleosynthesis revisited

We study the dependence of the primordial nuclear abundances as a function of the electromagnetic fine-structure constant alpha , keeping all other fundamental constants fixed. We update the leading nuclear reaction rates, in particular the electromagnetic contribution to the neutron-proton mass difference pertinent to beta -decays, and go beyond certain approximations made in the literature. In particular, we include the temperature-dependence of the leading nuclear reactions rates and assess the systematic uncertainties by using four different publicly available codes for Big Bang nucleosynthesis. Disregarding the unsolved so-called lithium-problem, we find that the current values for the observationally based {}^{2}text {H} and {}^{4}text {He} abundances restrict the fractional change in the fine-structure constant to less than 2% , which is a tighter bound than found in earlier works on the subject.

W-Boson Mass Anomaly as a Manifestation of Spontaneously Broken Additional SU(2) Global Symmetry on a New Fundamental Scale

Recently, the CDF Collaboration has announced a new precise measurement of the W-boson mass MW that deviates from the Standard Model (SM) prediction by 7σ. The discrepancy in MW is about ΔW ≃ 70 MeV and is probably caused by a beyond the SM physics. Within a certain scenario of extension of the SM, we obtain the relation ΔW ≃ 3α8πMW ≃ 70 MeV, where α is the electromagnetic fine structure constant. The main conjecture is the appearance of longitudinal components of the W-bosons as the Goldstone bosons of a spontaneously broken additional SU(2) global symmetry at distances much smaller than the electroweak symmetry breaking scale rEWSB. We argue that within this scenario, the masses of charged Higgs scalars can obtain an electromagnetic radiative contribution which enhances the observed value of MW± with respect to the usual SM prediction. Our relation for ΔW follows from the known one-loop result for the corresponding effective Coleman–Weinberg potential in combination with the Weinberg sum rules.

Thermoelectric properties and Wiedemann-Franz-like relations in mixed-dimensional QEDs from particle-vortex dualities

We consider the thermoelectric properties of the mixed-dimensional quantum electrodynamics of the relativistic Dirac fermion and Wilson-Fisher boson. These models are self-dual, and can form nontrivial many-body phases depending on the values of chemical potential, background magnetic field and the electromagnetic fine-structure constant. Using particle-vortex duality, we derive a variety of thermoelectric relations for strongly interacting phases with classic paradigms such as the Wiedemann-Franz law and the Mott's relation in the dual weakly interacting regimes. Besides, at the self-dual point, for the fermionic theory we find the ratio of thermal conductivity of electrical conductivity depends on the determinant of the Seebeck tensor and the phenomenological parameter Hall angle ${\ensuremath{\theta}}_{H}$. As for the bosonic theory, the dual fermion description explains how its Seebeck tensor varies depending on the dynamic regime characterized by ${\ensuremath{\theta}}_{H}$.

Robust laboratory limits on a cosmological spatial gradient in the electromagnetic fine-structure constant from accelerometer experiments

Quasar absorption spectral data indicate the presence of a spatial gradient in the electromagnetic fine-structure constant $\ensuremath{\alpha}$ on cosmological length scales. We point out that experiments with accelerometers, including torsion pendula and atom interferometers, can be used as sensitive probes of cosmological spatial gradients in the fundamental constants of nature, which give rise to equivalence-principle-violating forces on test masses. Using laboratory data from the E\"ot-Wash experiment, we constrain spatial gradients in $\ensuremath{\alpha}$ along any direction to be $|\mathbf{\ensuremath{\nabla}}\ensuremath{\alpha}/\ensuremath{\alpha}|<6.6\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}{(\text{Glyr})}^{\ensuremath{-}1}$ at $95%$ confidence level. Our result represents an order of magnitude improvement over laboratory bounds from clock-based searches for a spatial gradient in $\ensuremath{\alpha}$ directed along the observed cosmological $\ensuremath{\alpha}$-dipole axis. Improvements to accelerometer experiments in the foreseeable future are expected to provide sufficient sensitivity to test the cosmological $\ensuremath{\alpha}$ dipole seen in astrophysical data.

Testing the violation of the equivalence principle in the electromagnetic sector and its consequences in f(T) gravity

A violation of the distance-duality relation is directly linked with a temporal variation of the electromagnetic fine-structure constant. We consider a number of well-studied f(T) gravity models and we revise the theoretical prediction of their corresponding induced violation of the distance-duality relationship. We further extract constraints on the involved model parameters through fine-structure constant variation data, alongside with supernovae data, and Hubble parameter measurements. Moreover, we constrain the evolution of the effective f(T) gravitational constant. Finally, we compare with revised constraints on the phenomenological parametrisations of the violation of the equivalence principle in the electromagnetic sector.

An update on fine-tunings in the triple-alpha process

The triple-alpha process, whereby evolved stars create carbon and oxygen, is believed to be fine-tuned to a high degree. Such fine-tuning is suggested by the unusually strong temperature dependence of the triple-alpha reaction rate at stellar temperatures. This sensitivity is due to the resonant character of the triple-alpha process, which proceeds through the so-called “Hoyle state” of {}^{12}mathrm{C} with spin-parity 0^+. The question of fine-tuning can be studied within the ab initio framework of nuclear lattice effective field theory, which makes it possible to relate ad hoc changes in the energy of the Hoyle state to changes in the fundamental parameters of the nuclear Hamiltonian, which are the light quark mass m_q and the electromagnetic fine-structure constant alpha _mathrm{em}. Here, we update the effective field theory calculation of the sensitivity of the triple-alpha process to small changes in the fundamental parameters. In particular, we consider recent high-precision lattice QCD calculations of the nucleon axial coupling g_A, as well as new and more comprehensive results from stellar simulations of the production of carbon and oxygen. While the updated stellar simulations allow for much larger ad hoc shifts in the Hoyle state energy than previously thought, recent lattice QCD results for the nucleon S-wave singlet and triplet scattering lengths now disfavor the “no fine-tuning scenario” for the light quark mass m_q.

Novel signatures of dark matter in laser-interferometric gravitational-wave detectors

Dark matter may induce apparent temporal variations in the physical "constants", including the electromagnetic fine-structure constant and fermion masses. In particular, a coherently oscillating classical dark-matter field may induce apparent oscillations of physical constants in time, while the passage of macroscopic dark-matter objects (such as topological defects) may induce apparent transient variations in the physical constants. In this paper, we point out several new signatures of the aforementioned types of dark matter that can arise due to the geometric asymmetry created by the beam-splitter in a two-arm laser interferometer. These new signatures include dark-matter-induced time-varying size changes of a freely-suspended beam-splitter and associated time-varying shifts of the main reflecting surface of the beam-splitter that splits and recombines the laser beam, as well as time-varying refractive-index changes in the freely-suspended beam-splitter and time-varying size changes of freely-suspended arm mirrors. We demonstrate that existing ground-based experiments already have sufficient sensitivity to probe extensive regions of unconstrained parameter space in models involving oscillating scalar dark-matter fields and domain walls composed of scalar fields. In the case of oscillating dark-matter fields, Michelson interferometers $-$ in particular, the GEO600 detector $-$ are especially sensitive. The sensitivity of Fabry-Perot-Michelson interferometers, including LIGO, VIRGO and KAGRA, to oscillating dark-matter fields can be significantly increased by making the thicknesses of the freely-suspended Fabry-Perot arm mirrors different in the two arms. We also discuss how small-scale Michelson interferometers, such as the Fermilab holometer, could be used to perform resonant narrowband searches for oscillating dark-matter fields with enhanced sensitivity to dark matter.

Testing the variation of the fine structure constant with strongly lensed gravitational waves**Supported by the National Natural Science Fund of China (11775038, 11603005, 11647307)

The possible variation of the electromagnetic fine structure constant, αe, at cosmological scales has aroused great interest in recent years. Strongly lensed gravitational waves (GWs) and their electromagnetic counterparts could be used to test this variation. Under the assumption that the speed of a photon can be modified, whereas the speed of a GW is the same as predicted by general relativity, and they both propagate in a flat Friedman-Robertson-Walker universe, we investigated the difference in time delays of the images and derived the upper bound of the variation of αe. For a typical lensing system in the standard cosmological models, we obtained Bcosθ⩽1.85 × 10−5, where B is the dipolar amplitude and θ is the angle between observation and the preferred direction. Our result is consistent with the most up-to-date observations on αe. In addition, the observations of strongly lensed GWs and their electromagnetic counterparts could be used to test which types of alternative theories of gravity can account for the variation of αe.

Spatial and temporal variations of the fine-structure constant in the Finslerian universe**Supported by Fundamental Research Funds for Central Universities (106112016CDJCR301206), National Natural Science Fund of China (11305181, 11547035, 11603005), and Open Project Program of State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, China (Y5KF181CJ1).

Recent observations show that the electromagnetic fine-structure constant, αe, may vary with space and time. In the framework of Finsler spacetime, we propose here an anisotropic cosmological model, in which both spatial and temporal variations of αe are allowed. Our model naturally leads to the dipole structure of αe, and predicts that the dipole amplitude increases with time. We fit our model to the most up-to-date measurements of αe from the quasar absorption lines. It is found that the dipole direction points towards (l,b) = (330.2°±7.3°,−13.0°±5.6°) in galactic coordinates, and the anisotropic parameter is b0 = (0.47±0.09) × 10−5, which corresponds to a dipole amplitude (7.2±1.4)×10−8 at redshift z = 0.015. This is consistent with the upper limit of the variation of αe measured in the Milky Way. We also fit our model to Union2.1 type Ia supernovae, and find that the preferred direction of Union2.1 is consistent with the dipole direction of αe.

Leading hadronic contributions to the running of the electroweak coupling constants from lattice QCD

The quark-connected leading-order hadronic contributions to the running of the electromagnetic fine structure constant, $\alpha_{\rm QED}$, and the weak mixing angle, $\theta_W$, are determined by a four-flavour lattice QCD computation with twisted mass fermions. Full agreement of the results with a phenomenological analysis is observed with an even comparable statistical uncertainty. We show that the uncertainty of the lattice calculation is dominated by systematic effects which then leads to significantly larger errors than obtained by the phenomenological analysis.

Electromagnetic—Pure Gravity Connection via Hardy’s Quantum Entanglement

Pure gravity in eight dimensional super space possesses twenty degrees of freedom. Gauging these generalized coordinates in terms of a single self entangled Hardy type quantum particle we retrieve one hundred and thirty seven isometries corresponding to the well known value of the inverse electromagnetic fine structure constant. The deep implications of this thought provoking result are discussed in a general physical context.

Dependence of the triple-alpha process on the fundamental constants of nature

We present an ab initio calculation of the quark mass dependence of the ground state energies of ^4He, ^8Be and ^{12}C, and of the energy of the Hoyle state in ^{12}C. These investigations are performed within the framework of lattice chiral Effective Field Theory. We address the sensitivity of the production rate of carbon and oxygen in red giant stars to the fundamental constants of nature by considering the impact of variations in the light quark masses and the electromagnetic fine-structure constant on the reaction rate of the triple-alpha process. As carbon and oxygen are essential to life as we know it, we also discuss the implications of our findings for an anthropic view of the Universe. We find strong evidence that the physics of the triple-alpha process is driven by alpha clustering, and that shifts in the fundamental parameters at the \simeq 2 - 3 % level are unlikely to be detrimental to the development of life. Tolerance against much larger changes cannot be ruled out at present, given the relatively limited knowledge of the quark mass dependence of the two-nucleon S-wave scattering parameters. Lattice QCD is expected to provide refined estimates of the scattering parameters in the future.

Symmetry of two-particle mass shell and its impact on e-e-scattering

A proof is presented, based on the geometry of the two-electron mass hyperboloid, of Wyler's formula for the electromagnetic fine-structure constant. This proof provides evidence that the two-electron state space in e-e-scattering matches an irreducible two-particle representation of the Poincaré group. Electromagnetic scattering, as described by perturbative quantum electrodynamics, then has to be understood as a sequence of iterated transitions between pure (separable) product states and entangled two-electron states of an irreducible representation of the Poincaré group.

Knot wormholes and the dimensional invariant of exceptional Lie groups and Stein space hierarchies

The present short note points out a most interesting and quite unexpected connection between the number of distinct knot as a function of their crossing number and exceptional Lie groups and Stein space hierarchies. It is found that the crossing number 7 plays the role of threshold similar to 4 and 5 in E-infinity theory and for the 11 crossing the number of distinct knots is very close to 4 α ¯ 0 + 1 = 548 + 1 = 549 , where α ¯ 0 = 137 is the inverse integer electromagnetic fine structure constant. This is particularly intriguing in view of a similar relation pertinent to the 17 two and three Stein spaces where the total dimension is ∑ 1 17 Stein = 5 α ¯ 0 + 1 = 685 + 1 = 686 , as well as the sum of the eight exceptional Lie symmetry groups ∑ i = 1 8 | E i | = 4 α ¯ 0 = 548 . The slight discrepancy of one is explained in both cases by the inclusion of El Naschie’s transfinite corrections leading to ∑ i = 1 8 | E i | = ( 4 ) ( 137 + k 0 ) = 548.328157 and ∑ i = 1 17 Stein = ( 5 ) ( 137 + k 0 ) = 685.41097 , where k o = ϕ 5(1 − φ 5) and φ = 5 - 1 / 2 .

Kac–Moody exceptional E12 from simplictic tiling

We give various derivations for the order of a new non classical exceptional Lie group E12. We start from the simplest polyhedra of ordinary three dimensional space and arrive at the exact integer value ∣E12∣ = 685. Subsequently we show that a corresponding infinite dimensional but hierarchal KAC–Moody algebra called 4D fusion algebra leads to an exact transfinite dimension equal to Dim E 12 = ( 5 ) ( α ¯ o ) = 685.410197 , where α ¯ o = 137.082039325 is the E-infinity electromagnetic fine structure constant.

Using Witten’s five Brane theory and the holographic principle to derive the value of the electromagnetic fine structure constant [formula omitted

Using the 528 states of Witten’s five Brane theory in conjunction with the holographic principles we give various derivations for the inverse electromagnetic fine structure constant. Relations to the exceptional Lie group F 4 used to model a gravity-weak field are also considered.

P-Adic unification of the fundamental forces and the standard model

Since the P-Adic expansion of α ¯ o ≅ 137 with respect to P = 2 is ‖ 137 ‖ 2 = 1 and noting that α ¯ o is both the inverse electromagnetic fine structure constant of electromagnetism and the number of chiral elementary particles of the standard model, then we conclude by virtue of an extended T-like duality that the coupling constant at ultra higher Planck energy is α ¯ QG = 1 and the number of particles in this case is also N = 1. Subsequently it is argued that this is the simplest possible statement on unification of all the fundamental forces of Nature.

Noether’s theorem, exceptional Lie groups hierarchy and determining 1/α≅137 of electromagnetism

Noether’s theorem relating conservation laws with symmetry is applied in conjunction with the exceptional Lie group hierarchy, the holographic principles and E-infinity theory to calculate the electromagnetic fine structure constant. Various schemes are suggested utilizing the fundamentals of heterotic strings as well as P-Brane theory leading to essentially the same value of 1/α ≅ 137 in complete agreement with the well-established experimental evidences.

On D. Gross’ criticism of S. Eddington and an exact calculation of αo¯≃137

Abstract While Sir Arthur Stanley Eddington attempts to derive α o ¯ ≃ 137 mathematically may be considered to be a stretch, as correctly noted by Nobel laureate David Gross, in the meantime such a theoretical derivation is possible and feasible. In the present work, we show that the inverse electromagnetic fine structure constant may be derived in various ways using a combination of the Green, Shwarz, Witten and Gross string theory and the ‘t Hooft-Susskind and Maldacena holographic principles.

Rigorous derivation of the inverse electromagnetic fine structure constant α¯=1/137.036 using super string theory and the holographic boundary of E-infinity

Abstract An extremely simple and elementary but rigorous derivation of the inverse electromagnetic fine structure constant is given using super strings and the holographic boundary.