Polarization Whorls from M87* at the Event Horizon Telescope

TL;DR

This paper predicts distinctive polarization whorls near the event horizon of M87* black hole using conformal symmetry, aiding interpretation of upcoming EHT polarimetric images.

Contribution

It introduces an analytical model based on conformal symmetry to predict polarization patterns near a high-spin black hole's horizon.

Findings

Predicted polarization whorls aligned with black hole spin

Identified distinctive near-horizon polarization patterns

Provided a framework for interpreting EHT polarimetric data

Abstract

The Event Horizon Telescope (EHT) is expected to soon produce polarimetric images of the supermassive black hole at the center of the neighboring galaxy M87. There are indications that this black hole is rapidly spinning. General relativity predicts that such a high-spin black hole has an emergent conformal symmetry near its event horizon. In this paper, we use this symmetry to analytically predict the polarized near-horizon emissions to be seen at the EHT and find a distinctive pattern of whorls aligned with the spin.