Related papers: Magnetic ghosts and monopoles
We study the magnetic excitations of a square lattice spin-ice recently produced in an artificial form, as an array of nanoscale magnets. Our analysis, based upon the dipolar interaction between the nanomagnetic islands, correctly…
Current-carrying flows, in the laboratory and in astrophysical jets, can form remarkably stable magnetic structures. Decades of experience shows that such flows often build equilibria that reverse field directions, evolving to an MHD Taylor…
When ferromagnetic particles are suspended at an interface under magnetic fields, dipole-dipole interactions compete with capillary attraction. This combination of forces has recently given promising results towards controllable…
Magnetic monopoles, that are particle-like field configurations with which one can associate a topological charge, widely exist in various three dimensional condensate systems. In this paper, by making use of \emph{Duan}'s topological…
Magnetic monopoles have provided a rich field of study, leading to a wide area of research in particle physics, solid state physics, ultra-cold gases, superconductors, cosmology, and gauge theory. So far, no true magnetic monopoles were…
Collisions of two weakly nonlinear, $a_0 \ll 1$, counter-propagating EM pulses in pair plasma leave behind a long-surviving collection of localized waves, {\it an electromagnetic ghost}. Waves are trapped (localized) by the random large…
Negative kinetic energies correspond to ghost degrees of freedom, which are potentially of relevance for cosmology, quantum gravity, and high energy physics. We present a novel wide class of stable mechanical systems where a positive energy…
In classical mechanics, solutions can be classified according to their stability. Each of them is part of the possible trajectories of the system. However, the signatures of unstable solutions are hard to observe in an experiment, and most…
I give a theoretical overview of magnetic monopoles, focusing on the physical perspective of monopoles as hypothetical particles rather than as mathematical objects. I argue that monopoles are exceptionally interesting hypothetical…
We summarize some predictions from the model of supermassive object with magnetic monopoles which match up with recent astronomical observations quantitatively. They may be the signals for existence of magnetic monopoles in the supermassive…
Electrically charged particles, such as the electron, are ubiquitous. By contrast, no elementary particles with a net magnetic charge have ever been observed, despite intensive and prolonged searches. We pursue an alternative strategy,…
We discuss the appareance of ordered structures in assemblies of magnetic particles. The phenomenon occurs when dipolar interactions and the thermal motion of the particles compete, and is mediated by screening and excluded volume effects.…
Ghost fields have reemerged in a handful of phenomenologically motivated cosmological and particle physics scenarios, and most recently in a cyclic mechanism to address the fine-tuning of gauge couplings in the standard model. We study the…
According to the adiabatic approximation atoms moving in a magnetic trap keep their magnetic states. We investigate the validity of this approximation for quantum condensates, where a change of field's direction generates effective…
Ordered mechanical systems typically have one or only a few stable rest configurations, and hence are not considered useful for encoding memory. Multistable and history-dependent responses usually emerge from quenched disorder, for example…
The possibilities of combining several degrees of freedom inside a unique material have recently been highlighted in their dynamics and proposed as information carriers in quantum devices where their cross-manipulation by external…
Ultracold atomic spin mixtures develop rich and intriguing magnetic properties when an external radiation coherently couples different spin states. In particular, the coupled mixture may acquire a critical behavior when the spin…
The uniform states of a model for one-dimensional chains of thin magnetic islands on a nonmagnetic substrate coupled via dipolar interactions are described here. Magnetic islands oriented with their long axes perpendicular to the chain…
In the past several years, many important innovations in nanotechnology were made. Today it becomes possible to make nanosize magnetic particles, and development of high storage-density magnetic device is desired. In such a magnetic…
Motivated by recent results on small and hollow magnetic monopoles and on core and shell bimagnetic nanoparticles, we propose the construction of bimagnetic monopoles, which are structures that accommodate a magnetic monopole inside another…