# Exploring Gravitational Lensing

## TL;DR

This paper discusses the concept of gravitational lensing from historical, didactic, and theoretical perspectives, highlighting Einstein's explorations and the educational potential of this topic.

## Contribution

It provides a systematic overview of gravitational lensing, emphasizing its implications, historical development, and pedagogical applications based on Einstein's manuscripts.

## Key findings

- Einstein explored multiple pathways in gravitational lensing implications.
- The basic lensing equation links geometrical optics to gravitational effects.
- Educational discussions of lensing can be enriched using Einstein's original manuscripts.

## Abstract

In this article, we discuss the idea of gravitational lensing, from a systematic, historical and didactic point of view. We show how the basic lensing equation together with the concepts of geometrical optics opens a space of implications that can be explored along different dimensions. We argue that Einstein explored the idea along different pathways in this space of implication, and that these explorations are documented by different calculational manuscripts. The conceptualization of the idea of gravitational lensing as a space of exploration also shows the feasibility of discussing the idea in the classroom using some of Einstein's manuscripts.