Who developed the first laser theory in 1916?

The development of the first laser theory in 1916 is attributed to Albert Einstein. In that year, he introduced the concept of stimulated emission, which is the fundamental principle underlying laser technology. Einstein's theory described how an incoming photon could stimulate an excited atom to emit another photon that is coherent with the first, essentially amplifying the light. This principle laid the groundwork for the later development of lasers.

Einstein's work on this topic was crucial because it provided the theoretical foundation that would eventually lead to the practical realization of lasers in the 20th century. The amplification of light through stimulated emission is a key part of how lasers operate, distinguishing them from other forms of light sources.

While other figures like Maiman are significant in the history of laser development—specifically for creating the first operating laser in 1960—Einstein's theoretical contributions came much earlier and are recognized as the starting point for laser science.