Contrary to popular belief, asymptotically anti-de Sitter solutions of gravitational theories cannot be obtained by taking initial data (satisfying the constraints) on a spacelike surface, and choosing an arbitrary conformal metric on the timelike boundary at infinity. There are an infinite number of corner conditions that also must be satisfied where the initial data surface hits the boundary. These are well known to mathematical relativists, but to make them more widely known we give a simple explanation of why these conditions exist and discuss some of their consequences. An example is given which illustrates their power. Some implications for holography are also mentioned.

中文翻译：

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全息中的引力角条件

与流行的看法相反，引力理论的渐近反德西特解不能通过在类空间表面上获取初始数据（满足约束）并在无穷远的时间边界上选择任意保形度量来获得。在初始数据表面碰到边界的地方也必须满足无数的角点条件。这些对于数学相对论者来说是众所周知的，但为了让它们更广为人知，我们对这些条件存在的原因进行了简单的解释，并讨论了它们的一些后果。给出了一个例子来说明它们的力量。还提到了对全息术的一些影响。