
TL;DR
This paper explores the optical signatures of gravastars, a super-compact alternative to black holes, demonstrating that their unique photon orbit features produce distinguishable images that could be observed with future high-resolution telescopes.
Contribution
It introduces a detailed model of gravastar optical images, showing how their photon orbit structure creates observable differences from black holes.
Findings
Unstable photon orbits can exist around gravastars.
Distinct optical images, such as bright disks and dark rings, differentiate gravastars from black holes.
Future VLBI observations could identify gravastars based on their unique images.
Abstract
Direct observation of black holes is one of the grand challenges in astronomy. If there are super-compact objects which possess unstable circular orbits of photons, however, it may be difficult to distinguish them from black holes by observing photons. As a model of super-compact objects, we consider a gravastar (gravitational-vacuum-star) which was originally proposed by Mazur and Mottola. For definiteness, we adopt a spherical thin-shell model of a gravastar developed by Visser and Wiltshire, which connects interior de-Sitter geometry and exterior Schwarzschild geometry. We find that unstable circular orbits of photons can appear around the gravastar. Then, we investigate the optical images of the gravastar possessing unstable circular orbits, with assuming the optically transparent surface of it and two types of optical sources behind the gravastar: (i) an infinite optical plane and…
Peer Reviews
No public reviews on file for this paper yet. If you reviewed it on a platform where reviews are public (OpenReview, ICLR, NeurIPS, ICML), you can paste yours below so the community can read it here.
Videos
No videos yet. Explain this paper in a talk, walkthrough, or lecture? Add one.
