Related papers: Cosmic Strings - Dead Again?
Appearance of cosmic strings in the early Universe is a common manifestation of new physics typically linked to some high energy scale. In this paper, we discuss a different situation, where a model underlying cosmic string formation is…
Cosmic strings, topological defects predicted by high-energy theories, may contribute to the late-time expansion of the Universe, effectively mimicking dynamical dark energy. We investigate four phenomenological extensions of the…
It has been known long time ago that the low energy dynamics of open-strings is described by non-abelian gauge theories in the same way that the low energy effective description of closed strings is governed by Einstein's gravity. In this…
We consider an extension of the Standard Model, where the difference between the baryon number $B$ and the lepton number $L$ is gauged with an Abelian gauge field, in order to explain the exact conservation of $B-L$. To avoid a gauge…
For vortex strings in the Abelian Higgs model and D-strings in superstring theory, both of which can be regarded as cosmic strings, we give analytical study of reconnection (recombination, inter-commutation) when they collide, by using…
A metastable cosmic-string network is a generic consequence of many grand unified theories (GUTs) when combined with cosmic inflation. Metastable cosmic strings are not topologically stable, but decay on cosmic time scales due to pair…
We describe a new mechanism, whose ingredients are realised in string compactifications, for the formation of cosmic (super)string networks. Oscillating string loops grow when their tension $\mu$ decreases with time. If $2H + \dot{\mu}/\mu…
We show that axions can be produced from Abelian-Higgs cosmic strings due to the axion-gauge coupling. The strong magnetic field is confined in the string, and the electric field is induced around the moving string, allowing axion…
Cosmic string networks are the best motivated relics of cosmological phase transitions, being unavoidable in many physically plausible extensions of the Standard Model. Most studies, including those providing constraints from and forecasts…
We extend and develop our previous work on the evolution of a network of cosmic strings. The new treatment is based on an analysis of the probability distribution of the end-to-end distance of a randomly chosen segment of left-moving string…
We investigate some consequences of a specific non-conservation of the energy-momentum tensor on the physics of certain cosmic string configurations. This non-conservation is induced by a new gravitational theory recently introduced as an…
Black holes, the simplest solution to Einstein's field equations, do not emit light, making their observations a major challenge for researchers. However, discovery of binary black holes (BBHs) in 2015 by LIGO has transformed the study of…
In this paper we analyze Abelian-Higgs strings in a phenomenological model that takes quantum effects in curved space-time into account. This model, first introduced by Rastall, cannot be derived from an action principle. We formulate…
Using the formalism developed in a previous paper we analyze the cosmological implications of our conclusions concerning the scaling behaviour of a network of cosmic strings, in particular the idea that once gravitational back-reaction…
It has been pointed out that cosmic string solutions can exist in gauge field theories with broken symmetry even when $\pi _1(G/H)$ is trivial. The stability of such semilocal defects is not guaranteed by topology and depends on dynamical…
We investigate the string solutions and cosmological implications of the gauge ${\rm U(1)_Z}\,\times$ global ${\rm U(1)_{PQ}}$ model. With two hierarchical symmetry-breaking scales, the model exhibits three distinct string solutions: a…
New physics beyond the Standard Model can give rise to stochastic gravitational-wave backgrounds, for example through cosmic strings. In this way, gravitational-wave searches with pulsar-timing arrays as well as existing and future laser…
We show that the cosmological abundance of string axions is much smaller than naive estimates if the Hubble scale of inflation, $H_{\rm inf}$, is sufficiently low (but can still be much higher than the axion masses) and if the inflation…
Using lattice field simulations of the Abelian-Higgs model, we characterize the simultaneous emission of (scalar and gauge) particles and gravitational waves (GWs) by local string loops. We use {\it network} loops created in a phase…
Cosmic strings are predicted in many models beyond the Standard Model of particle physics. In models which admit strings, a network of strings will inevitably be formed in a phase transition in the early universe and will persist to the…