Einstein on the beach , one of the first operas to employ electronically amplified instrumentation, was written by

Philip  Glass

Explanation:

   Einstein on the Beach is an opera in four acts, composed by Philip Glass in 1976. The work is bigger than the senses can produce, it is more intense than we can digest, it is deeper than the impressions that can be described about it.

It was an opera that became a defining moment for the two artists, even if they did not know it, in the same way that it became a myth of the musical theater itself, then undergoing a profound transformation, with the arrival of film adaptations for the stage and the television model controlling time and interaction with the viewer.

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