Lecture

Cosmic Magnetic Fields: Production and Dynamics

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Description

This lecture discusses the production of cosmic magnetic fields during the preheating phase after inflation. The instructor outlines the theoretical framework, referencing significant works from the 1990s that introduced the concept of preheating, where the inflaton field decays into particles in a non-perturbative manner. The dynamics of tachyonic preheating are explained, highlighting how instabilities can lead to the generation of long-wave configurations of fields, including magnetic fields. The lecture also covers the role of quantum initial conditions and the transition from quantum to classical fields, emphasizing the importance of high occupation numbers in this process. The instructor presents simulations that demonstrate the growth of magnetic fields and their correlation with the Higgs field, as well as the implications for baryogenesis and gravitational wave production. The discussion concludes with insights into the significance of these findings for understanding the early universe and the formation of large-scale structures in the cosmos.

Official source

Ontological neighbourhood

Astronomy

Astrophysics: Physical cosmology

Related concepts (32)

Chronology of the universe

The chronology of the universe describes the history and future of the universe according to Big Bang cosmology. Research published in 2015 estimates the earliest stages of the universe's existence as taking place 13.8 billion years ago, with an uncertainty of around 21 million years at the 68% confidence level. For the purposes of this summary, it is convenient to divide the chronology of the universe since it originated, into five parts.

Cosmology

Cosmology () is a branch of physics and metaphysics dealing with the nature of the universe. The term cosmology was first used in English in 1656 in Thomas Blount's Glossographia, and in 1731 taken up in Latin by German philosopher Christian Wolff, in Cosmologia Generalis. Religious or mythological cosmology is a body of beliefs based on mythological, religious, and esoteric literature and traditions of creation myths and eschatology. In the science of astronomy, cosmology is concerned with the study of the chronology of the universe.

Universe

The universe is all of space and time and their contents, including planets, stars, galaxies, and all other forms of matter and energy. The Big Bang theory is the prevailing cosmological description of the development of the universe. According to this theory, space and time emerged together 13.787billion years ago, and the universe has been expanding ever since the Big Bang. While the spatial size of the entire universe is unknown, it is possible to measure the size of the observable universe, which is approximately 93 billion light-years in diameter at the present day.

Higgs mechanism

In the Standard Model of particle physics, the Higgs mechanism is essential to explain the generation mechanism of the property "mass" for gauge bosons. Without the Higgs mechanism, all bosons (one of the two classes of particles, the other being fermions) would be considered massless, but measurements show that the W+, W−, and Z0 bosons actually have relatively large masses of around 80 GeV/c2. The Higgs field resolves this conundrum. The simplest description of the mechanism adds a quantum field (the Higgs field) which permeates all of space to the Standard Model.

Inflation (cosmology)

In physical cosmology, cosmic inflation, cosmological inflation, or just inflation, is a theory of exponential expansion of space in the early universe. The inflationary epoch is believed to have lasted from seconds to between and seconds after the Big Bang. Following the inflationary period, the universe continued to expand, but at a slower rate. The acceleration of this expansion due to dark energy began after the universe was already over 7.7 billion years old (5.4 billion years ago).

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