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The Boundary of the Future

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 نشر من قبل Grant Remmen
 تاريخ النشر 2017
  مجال البحث فيزياء
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We prove that the boundary of the future of a surface $K$ consists precisely of the points $p$ that lie on a null geodesic orthogonal to $K$ such that between $K$ and $p$ there are no points conjugate to $K$ nor intersections with another such geodesic. Our theorem has applications to holographic screens and their associated light sheets and in particular enters the proof that holographic screens satisfy an area law.



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