Vector modes from primordial magnetic fields remain constant in a kination epoch and source second-order curvature perturbations scaling as P_R(k) ∝ k^{-5}, sufficient for PBH dark matter abundance in a Ratra-type magnetogenesis model.
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The origin, evolution and signatures of primordial magnetic fields
19 Pith papers cite this work. Polarity classification is still indexing.
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Pith papers citing it
abstract
The universe is magnetized on all scales probed so far. On the largest scales, galaxies and galaxy clusters host magnetic fields at the micro Gauss level coherent on scales up to ten kpc. Recent observational evidence suggests that even the intergalactic medium in voids could host a weak $\sim 10^{-16}$ Gauss magnetic field, coherent on Mpc scales. An intriguing possibility is that these observed magnetic fields are a relic from the early universe, albeit one which has been subsequently amplified and maintained by a dynamo in collapsed objects. We review here the origin, evolution and signatures of primordial magnetic fields. After a brief summary of magnetohydrodynamics in the expanding universe, we turn to magnetic field generation during inflation and other phase transitions. We trace the linear and nonlinear evolution of the generated primordial fields through the radiation era, including viscous effects. Sensitive observational signatures of primordial magnetic fields on the cosmic microwave background, including current constraints from Planck, are discussed. After recombination, primordial magnetic fields could strongly influence structure formation, especially on dwarf galaxy scales. The resulting signatures on reionization, the redshifted 21 cm line, weak lensing and the Lyman-$\alpha$ forest are outlined. Constraints from radio and $\gamma$-ray astronomy are summarized. Astrophysical batteries and the role of dynamos in reshaping the primordial field are briefly considered. The review ends with some final thoughts on primordial magnetic fields.
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The paper calculates multifrequency angular power spectra of the 21 cm line for models with primordial magnetic fields of strength 4 nG and spectral indices -2.9 and -2.5, then estimates signal-to-noise ratios for uGMRT, MeerKAT and SKA1-MID.
Lattice simulations show that Schwinger currents saturate gauge-field production in axion inflation, yielding universal conductivity and magnetic-field values at the onset of strong backreaction.
MACSJ0417’s giant radio halo shows spectral steepening and radio–X-ray correlation consistent with turbulence from a 6:1 off-axis merger that preserved the cool core; pure hadronic models are energetically excluded.
Coupling dark photons to standard photons enables adequate primordial magnetogenesis without strong-coupling or backreaction issues.
A self-consistent Parker bound, anchored in the dynamo seed eigenmode and including turbulent pre-acceleration of monopoles, relaxes the standard extended Parker bound by roughly two orders of magnitude at low and intermediate monopole masses.
Multi-phase inflation with chiral vector interactions generates amplified primordial magnetic fields that induce a detectable circularly polarized gravitational-wave background.
Proposes that axion-photon conversion in pre-CMB helical magnetic fields imprints detectable V-mode polarization in the CMB, allowing CLASS 40 GHz observations to constrain ALP masses 10^{-10} to 10^{-8} eV and their photon coupling under optimistic nG field assumptions.
A symbiotic axion-dilaton system sources a moderately chiral dark U(1) magnetic field of astrophysically relevant strength during radiation domination through tachyonic amplification without fine-tuning.
Inflationary magnetic fields induce curvature perturbations that form ultralight PBHs, generating a stochastic GW background with model-specific features.
Electromagnetism is reformulated from relativistic fluid dynamics via pull-back of differential forms from matter space, imposing kinematical constraints from the absence of four-forms and identifying a preferred frame where spacetime field strength matches the intrinsic matter-space two-form.
Primordial magnetic fields enhance low-mass halo abundance at Cosmic Dawn, advancing Lyman-alpha coupling, X-ray heating and reionization and imprinting detectable signatures on global and fluctuating 21-cm signals observable by HERA and SKA.
Finite conductivity of the plasma suppresses parametric resonance amplification of electromagnetic fields from ultralight pseudoscalar dark matter, making it impossible to generate magnetic fields of sufficient strength in cosmic voids for observationally viable couplings.
Superposition of static galactic magnetic dipoles is screened by intergalactic plasma and cannot account for lower bounds on magnetic fields in cosmic voids from blazar gamma-ray data.
A research framework combining XRISM turbulent velocity maps with SKA rotation measure grids to break degeneracies between magnetic field strength and cosmic-ray energetics in galaxy clusters.
A review chapter summarizing theoretical 21-cm signatures from Cosmic Dawn and Reionization and their detectability with SKA-Low.
FRBs serve as cosmological probes via dispersion measure, scattering, and Faraday rotation to constrain baryon distribution, expansion history, magnetic fields, and fundamental physics effects.
This review chapter summarizes the cosmic web's theoretical framework, recent radio observations of diffuse gas, and the expected impact of the SKA on detecting baryons in filaments and cluster outskirts.
citing papers explorer
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Primordial Black Holes from Vector-Induced Curvature Perturbations Sourced by Primordial Magnetic Fields
Vector modes from primordial magnetic fields remain constant in a kination epoch and source second-order curvature perturbations scaling as P_R(k) ∝ k^{-5}, sufficient for PBH dark matter abundance in a Ratra-type magnetogenesis model.
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Effects of primordial magnetic fields on 21 cm multifrequency angular power spectra
The paper calculates multifrequency angular power spectra of the 21 cm line for models with primordial magnetic fields of strength 4 nG and spectral indices -2.9 and -2.5, then estimates signal-to-noise ratios for uGMRT, MeerKAT and SKA1-MID.
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Schwinger effect in axion inflation on a lattice
Lattice simulations show that Schwinger currents saturate gauge-field production in axion inflation, yielding universal conductivity and magnetic-field values at the onset of strong backreaction.
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Multi-Wavelength Signatures of a Giant Cometary Radio Halo in MACSJ0417-1154
MACSJ0417’s giant radio halo shows spectral steepening and radio–X-ray correlation consistent with turbulence from a 6:1 off-axis merger that preserved the cool core; pure hadronic models are energetically excluded.
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Dark photon -- Assisted Primordial Magnetogenesis
Coupling dark photons to standard photons enables adequate primordial magnetogenesis without strong-coupling or backreaction issues.
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Self-Consistent Parker Bound on Magnetic Monopoles
A self-consistent Parker bound, anchored in the dynamo seed eigenmode and including turbulent pre-acceleration of monopoles, relaxes the standard extended Parker bound by roughly two orders of magnitude at low and intermediate monopole masses.
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Chiral gravitational waves from multi-phase magnetogenesis
Multi-phase inflation with chiral vector interactions generates amplified primordial magnetic fields that induce a detectable circularly polarized gravitational-wave background.
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Probing Axion-Photon conversion via circular polarization imprints in the CMB $V$-mode observations
Proposes that axion-photon conversion in pre-CMB helical magnetic fields imprints detectable V-mode polarization in the CMB, allowing CLASS 40 GHz observations to constrain ALP masses 10^{-10} to 10^{-8} eV and their photon coupling under optimistic nG field assumptions.
-
Symbiotic Magnetogenesis during Radiation Domination
A symbiotic axion-dilaton system sources a moderately chiral dark U(1) magnetic field of astrophysically relevant strength during radiation domination through tachyonic amplification without fine-tuning.
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The Magnetic Origin of Primordial Black Holes: Ultralight PBHs and Secondary GWs
Inflationary magnetic fields induce curvature perturbations that form ultralight PBHs, generating a stochastic GW background with model-specific features.
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Electromagnetism from relativistic fluid dynamics
Electromagnetism is reformulated from relativistic fluid dynamics via pull-back of differential forms from matter space, imposing kinematical constraints from the absence of four-forms and identifying a preferred frame where spacetime field strength matches the intrinsic matter-space two-form.
-
Primordial Magnetic Fields at Cosmic Dawn: 21-cm Forecasts with HERA and SKA
Primordial magnetic fields enhance low-mass halo abundance at Cosmic Dawn, advancing Lyman-alpha coupling, X-ray heating and reionization and imprinting detectable signatures on global and fluctuating 21-cm signals observable by HERA and SKA.
-
Suppressed Magnetogenesis from Ultralight Dark Matter due to Finite Conductivity
Finite conductivity of the plasma suppresses parametric resonance amplification of electromagnetic fields from ultralight pseudoscalar dark matter, making it impossible to generate magnetic fields of sufficient strength in cosmic voids for observationally viable couplings.
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On the contribution of galaxies to the magnetic field in cosmic voids
Superposition of static galactic magnetic dipoles is screened by intergalactic plasma and cannot account for lower bounds on magnetic fields in cosmic voids from blazar gamma-ray data.
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Unravelling Turbulence and Magnetic Fields in Galaxy Clusters with SKA and XRISM
A research framework combining XRISM turbulent velocity maps with SKA rotation measure grids to break degeneracies between magnetic field strength and cosmic-ray energetics in galaxy clusters.
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High-Redshift Signatures from the Cosmic Dawn and the Epoch of Reionization
A review chapter summarizing theoretical 21-cm signatures from Cosmic Dawn and Reionization and their detectability with SKA-Low.
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Fast Radio Bursts as Cosmological Probes
FRBs serve as cosmological probes via dispersion measure, scattering, and Faraday rotation to constrain baryon distribution, expansion history, magnetic fields, and fundamental physics effects.
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The Large-Scale Structure of the Universe through the SKA lenses
This review chapter summarizes the cosmic web's theoretical framework, recent radio observations of diffuse gas, and the expected impact of the SKA on detecting baryons in filaments and cluster outskirts.
- Gravitational Waves from Post-Inflationary Magnetism: Direct and Scalar-Induced Contributions