arXiv subjects

Maricarmen A. Winkler

Publications and source records attributed to Maricarmen A. Winkler.

6 recordsLinked to original sources

arXiv2026

Frozen-In Gravitational Fields

Spacetime can undergo complex nonlinear evolution, as governed by the Einstein field equations, and a central challenge is to understand the geometric structures that arise, persist, and interact throughout its evolution. Using a formulation of Einstein equations that parallels nonlinear electrodynamics of continuous media, we show that general relativity admits gravitational field connections---two-surfaces and associated field lines whose connectivity is maintained by the spacetime dynamics. This gravitational frozen-in behavior is enabled by an ideal Ohm-type condition for the gravitational field. We further show that the same framework naturally leads to a conserved ``gravitational magnetic'' flux. A conserved gravitational helicity also emerges, with a clear topological interpretation in terms of gravitational field-line structures. These results identify well-defined topological constraints on admissible spacetime evolution and provide an organizing principle underlying the nonlinear dynamics of spacetime.

gr-qc↗

arXiv2025

Ultrarelativistic outflows in asymmetric magnetic reconnection

We present a one-fluid pair plasma magnetohydrodynamical model for asymmetric relativistic magnetic reconnection that incorporates the thermal-inertial effects of the plasma. We find the general scaling relation for the reconnection rate in a Sweet-Parker-type configuration. However, we show that under a specific highly asymmetric scenario, this magnetic reconnection process can produce ultrarelativistic plasma outflows, with velocities surpassing those of the inflow particles, and also, those found in symmetric cases. We highlight the significance of the asymmetry in enhancing particle acceleration and energy release.

physics.plasm-ph↗

arXiv2024

Accelerating solutions of the Korteweg-de Vries equation

The Korteweg-de Vries equation is a fundamental nonlinear equation that describes solitons with constant velocity. On the contrary, here we show that this equation also presents accelerated wavepacket solutions. This behavior is achieved by putting the Korteweg-de Vries equation in terms of the Painlevé I equation. The accelerated waveform solutions are explored numerically showing their accelerated behavior explicitly.

nlin.SI↗

arXiv2023

Existence of Korteweg-de Vries Solitons and Relevance of Relativistic Effects in a Dusty Electron-Ion Plasma

Nonlinear effects in the propagation of perturbations in a dusty electron-ion plasma is studied, considering fully relativistic wave motion. A multifluid model is considered for the particles, from which a KdV equation can be derived. In general, two different soliton solutions are found depending on the kind of dispersion of the KdV equation. We study when the dispersion coefficient of this equation is positive. In this case, two kind of behavior are possible, one associated with a slow wave mode, another with a fast wave mode. It is shown that, depending on the value of the system parameters, compressive and/or rarefactive solitons, or no soliton at all, can be found and that relativistic effects for ions are much more relevant than for electrons. It is also found that relativistic effects can strongly decrease the soliton amplitude for the slow mode, whereas for the fast mode they can lead to compressive-rarefactive soliton transitions and vice versa, depending on the dust charge density in both modes.

physics.plasm-ph↗

arXiv2023

Exact and paraxial Airy propagation of relativistic electron plasma wavepackets

The different forms of propagation of relativistic electron plasma wavepackets in terms of Airy functions are studied. It is shown that exact solutions can be constructed showing accelerated propagations along coordinates transverse to the thermal speed cone coordinate. Similarly, Airy propagation is a solution for relativistic electron plasma waves in the paraxial approximation. This regime is considered in time-domain, when paraxial approximation is considered for frequency, and in space-domain, when paraxial approximation is considered for wavelength. In both different cases, the wavepackets remains structured in the transverse plane. Using these solutions we are able to define generalized and arbitrary Airy wavepackets for electron plasma waves, depeding on arbitrary spectral functions. Examples of this construction are presented. These electron plasma Airy wavepackets are the most general solutions of this kind.

physics.plasm-ph↗

arXiv2022

Thermal-Inertial Effects on Relativistic Asymmetric Magnetic Reconnection

A general description for relativistic magnetic reconnection is given in terms of asymmetric inflow plasma conditions, such as plasma density, velocity magnetic field strength, and their respective thermal-inertial effects. In this work, we show that thermal-inertial effects increase reconnection rates, generalizing previous results. Furthermore, different reconnection rates can be defined depending on the initial asymmetric conditions for the inflow plasma into the reconnection region. We explore two possibilities for reconnection rates, which, depending on the asymmetric magnetization, display different strengths. We discuss the importance on defining appropriate reconnection rates for corresponding asymmetric plasma systems in the context of previous results.

physics.plasm-ph↗