Gibbons–Hawking–York boundary term (source code)

= Gibbons–Hawking–York boundary term
{wiki=Gibbons–Hawking–York_boundary_term}

The Gibbons–Hawking–York (GHY) boundary term is an important concept in the context of general relativity and gravitational action principles, particularly when dealing with the Einstein-Hilbert action, which describes the dynamics of gravity.