Influence of quintessence dark energy on the shadow of black hole

TL;DR

This paper explores how quintessence dark energy influences black hole shadows, analyzing effects on image features and brightness for different accretion profiles, highlighting the role of cosmological horizons and accretion dynamics.

Contribution

It provides a detailed analysis of black hole shadow features under quintessence dark energy, including the impact of accretion types and cosmological horizons, which is a novel investigation.

Findings

Photon sphere positions are unaffected by accretion type.

Infalling matter results in darker observed intensity due to Doppler effects.

Cosmological horizon proximity influences shadow appearance.

Abstract

We investigate the effects of quintessence dark energy on the shadows of black hole, surrounded by various profiles of accretions. For the thin disk accretion, the images of the black hole comprises the dark region and bright region, including direct emission, lensing rings and photon rings. Although their details depend on the form of the emission, generically, the direct emission plays a major role for the observed brightness of the black hole, while the lensing ring makes a small contribution and photon ring makes a negligible contribution. The existence of cosmological horizon also plays an important role in the shadows, since the observer in the domain of outer communications is nearby the cosmological horizon. For the spherically symmetric accretion, the static and infalling matters are considered. We find that the positions of photon spheres are the same for both static and infalling accretions. However, the observed specific intensity of the image for the infalling accretion is darker than the static accretion, due to the Doppler effect of the infalling movement.