English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Tools annual

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

We study a simple axionlike model with a charged scalar $\phi$ and adouble-charged scalar $\zeta$ of global $U(1)$ symmetry. A particular featureof our model is that a vacuum manifold is a torus knot. We consider ahierarchical symmetry-breaking scenario where $\zeta$ first condenses, givingrise to cosmic $\zeta$-strings, and the subsequent condensation of $\phi$ leadsto domain-wall formation spanning the $\zeta$-strings. We find that theformation of the walls undergoes two different regimes depending on themagnitude of an explicit breaking term of the relative $U(1)$ between $\zeta$and $\phi$. One is the weakly interacting regime where the walls areaccompanied by another cosmic $\phi$ strings. The other is the stronglyinteracting regime where no additional strings appear. In both regimes, neithera $\zeta$-string, a $\phi$-string nor a wall alone is topological, but thecomposite of an appropriate number of strings and walls as a whole istopologically stable, characterized by the fundamental homotopy group of thetorus knot. We confirm the formation and the structure of the string-wallsystem by first-principle cosmological two-dimensional simulations. We findstable string-wall composites at equilibrium, where the repulsive force between$\zeta$-strings and the tension of walls balances, and a novel reconnection ofthe string-wall composites.

String-wall composites winding around a torus knot vacuum in an axionlike model