Gamma Ray Bursts: back to the blackboard

TL;DR

This review highlights the disconnect between observational breakthroughs and theoretical models in Gamma Ray Burst research, emphasizing the need for new ideas and addressing contradictions in existing models, especially for Short GRBs.

Contribution

It critically assesses current GRB models, identifies contradictions with observations, and discusses potential new ideas like internal dissipation and beamed prompt radiation.

Findings

Early X-ray afterglows may originate from internal dissipation.

Prompt radiation could be beamed in the outflow frame.

Current models face significant observational contradictions.

Abstract

Exceptional observational breakthroughs in the field of Gamma Ray Burst research are not paralleled by theoretical advances. In this review, based on the introductory talk given at the "The Shocking Universe" meeting, I argue that any present day model of GRBs, especially of Short type, is grossly incomplete. I will highlight various contradictions with observations that many models face and briefly mention a number of ideas that might or might not work. In particular, I will discuss (i) a possibility that early X-ray afterglows are coming from internal dissipation, and not from the forwards shock; (ii) that prompt radiation is beamed in the outflow frame.