Definitions for "Event Horizon"
Event Horizon is a language for the description of reality, implemented as a distributed interactive simulation software. Using this software, a user should be able to write a description of a reality model, & run an accurate simulation of it.
the boundary surface surrounding a black hole, from outside of which nothing inside can be observed, because nothing inside that surface, even light, can escape beyond it. See also black hole and escape velocity.
The border around a black hole beyond which nothing, not even light, can escape the pull of gravity.