While active experimental searches and theoretical models explore potential scenarios for magnetic monopoles, standard electromagnetic theory and instructional texts state that they do not exist, and extensive experimental searches have failed to observe any to date.
Contrary to the electric charge that generates the electric field, magnetic charge (namely magnetic monopoles) does not exist in the elementary electromagnetism. Consequently, magnetic flux lines only form loops and cannot have a source or a sink in nature. It is thus extraordinary to find that magnetic monopoles can be pictured conceptually in topological materials. Specifically in the 2D topological insulators, the topological invariant corresponds to the total flux of an effective magnetic field (the Berry curvature) over the reciprocal space.It is thus tempting to wrap the 2D reciprocal space into a compact manifold--a torus, and imagine the total flux to originate from magnetic monopoles inside the torus with a quantized total charge. However, such a physically appealing picture has not been realized quantitatively: other than their existence in a toy (actually misleading) picture, the properties of the magnetic monopoles remain unknown. Here, we will address this long-standing problem by hunting down the magnetic monopoles in the reciprocal $k$-space. We will show that a simple and physically useful picture will arrive upon analytically continuing the system to a third imaginary momentum space. We then illustrate the evolution of the magnetic monopoles across the topological phase transition and use it to provide natural explanations on: 1) discontinuous jump of integer topological invariants, 2) the semi-metallic nature on the phase boundary, and 3) how a change of glo
By analyzing the coupling constant series and in particular the coupling of the electric, and combining it with additional key condition of fermions. it becomes vividly clear that magnetic monopoles could not exist in nature.
Ultra-high energy (UHE) photons above 10^{18} eV serve as valuable probes of fundamental physics. While typically produced in interactions involving charged particles, they could also originate from exotic sources such as annihilations of magnetically charged monopole-antimonopole pairs or decays of highly accelerated monopoles (10^{21} eV). Detecting such photons would impose constraints on monopole properties. Despite strong theoretical motivations and extensive experimental searches, no monopoles have been observed to date. A possible explanation beyond high monopole masses arises from Staruszkiewicz's quantum theory of infrared electromagnetic fields. His argument, rooted in the positivity of the Hilbert space norm, suggests that isolated magnetic monopoles may not be physically realizable. If correct, this would imply that while monopoles remain mathematically well-defined within field theories, only magnetically neutral configurations could exist in nature.
0 (5-6) Since magnetic monopoles do not exist, magnetic field lines do not terminate at … since magnetic monopoles do not exist as far as we know today. Therefore, the magnetic equivalent … no magnetic force on a stationary charge situated in a magnetic field. A magnetic field
solutions do not exist in the minimum standard model, but they do exist in some broken … (A.4) up ’ which states that magnetic monopoles do not exist. The form of eq. (A. 3) poses … continuous magnetic vector potential A exists in the presence of a magnetic monopole, vector
We report a search for highly ionizing magnetic monopoles in the cosmic-ray flux using a 2713-day dataset collected during 2015–2025 with the NOvA Far Detector, a 14-kt segmented detector located on Earth’s surface in Minnesota, United States. The search is sensitive to monopoles across a wide range of speeds, 7 × 10 - 4 < β < 0.995 , and is sensitive to masses as low as 2 × 10 5 GeV for the fastest monopoles. No signal was observed. With the detector’s large surface area and minimal overburden, we achieve the strongest flux limits reported to date in several regions of speed and mass. For heavy monopoles with masses above 10 13 GeV that are able to reach the detector from above or—crossing Earth—from below, we find a flux limit ϕ 90 % < 2 × 10 - 16 cm - 2 s - 1 sr - 1 (90% confidence level) for monopoles with 0.005 < β < 0.8 . Across the same range of speeds, we report a limit ϕ 90 % < 8 × 10 - 16 cm - 2 s - 1 sr - 1 for light monopoles with masses above 10 8 GeV that can reach the detector from above.
Everything we examined (6) — 5 independent sources
This check searched the claim as stated. It did not run a separate search for evidence against it.