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 Plus annual

Presents the access of premium content as premium feature

Premium Content

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 Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

In this work we describe an interesting application of a simplederivative-free optimization method to extract the quasinormal modes (QNM's) ofa massive scalar field propagating in a 4-dimensional Schwarzschild anti-deSitter black hole (Sch-AdS$_4$). In this approach, the problem to find theQNM's is reduced to minimize a real valued function of two variables and doesnot require any information about derivatives. In fact, our strategy requiresonly evaluations of the objective function to search global minimizers of theoptimization problem. Firstly, numerical experiments were performed to find theQNM's of a massless scalar field propagating in intermediate and largeSch-AdS$_4$ black holes. The performance of this optimization algorithm wascompared with other numerical methods used in previous works. Our resultsshowed to be in good agreement with those obtained previously. Finally, themassive scalar field case and its QNM's were also obtained and discussed.

A derivative-free optimization method to compute scalar perturbation of AdS black holes