Searching for Magnetic Monopoles with the Earth's Magnetic Field

Abstract

Magnetic monopoles have long been predicted in theory and could exist as a stable object in our universe. As they move around in galaxies, magnetic monopoles could be captured by astrophysical objects like stars and planets. Here, we provide a novel method to search for magnetic monopoles by detecting the monopole moment of the Earth's magnetic field. Using over six years of public geomagnetic field data obtained by the Swarm satellites, we apply Gauss's law to measure the total magnetic flux, which is proportional to the total magnetic charge inside the Earth. To account for the secular variation of satellite altitudes, we define an altitude-rescaled magnetic flux to reduce the dominant magnetic dipole contribution. The measured magnetic flux is consistent with the existing magnetic field model that does not contain a monopole moment term. We therefore set an upper limit on the magnetic field strength at Earth's surface from magnetic monopoles to be $|B_{\mathrm{m}}|<0.13$ nT at 95% confidence level, which is less than $2\times 10^{-6}$ of Earth's magnetic field strength. This constrains the abundance of magnetically-charged objects, including magnetic black holes with large magnetic charges.

arXiv comment14 pages, 5 figures

References in corpus (14)

• The String Landscape, Black Holes and Gravity as the Weakest Force
• The CHAOS-7 geomagnetic field model and observed changes in the South Atlantic Anomaly
• Black Holes in Magnetic Monopoles
• Monopoles in Weinberg-Salam Model
• A Classical Instability of Reissner-Nordstrom Solutions and the Fate of Magnetically Charged Black Holes
• Comments on magnetic black holes
• Magnetic monopoles revisited: Models and searches at colliders and in the Cosmos
• Magnetic monopole mass bounds from heavy ion collisions and neutron stars
• Searches for Relativistic Magnetic Monopoles in IceCube
• Phenomenology of Magnetic Black Holes with Electroweak-Symmetric Coronas
• Gravitationally bound monopoles
• Astrophysical hints for magnetic black holes
• Topologically stable, finite-energy electroweak-scale monopoles
• Constraints on Relic Magnetic Black Holes

Cited by in corpus (7)

• Black holes with electroweak hair
• Q-Monopole-Ball: A Topological and Nontopological Soliton
• On the cosmological abundance of magnetic monopoles
• Limits on the Carroll-Field-Jackiw electrodynamics from geomagnetic data
• Quark mass matrices inspired by a numerical relation
• Proceedings to the 27th Workshop "What Comes Beyond the Standard Models" Bled, July 8-17, 2024
• Do we understand the internal spaces of second quantized fermion and boson fields, with gravity included? Relation with strings theories