We investigate the properties of a fairly large class of boundary conditions for the linearised Einstein equations in the Riemannian setting, ones which generalise the linearised counterpart of boundary conditions proposed by Anderson. Through the prism of the quest to quantise gravitational waves in curved spacetimes, we study their properties from the point of view of ellipticity, gauge invariance, and the existence of a spectral gap.

中文翻译：

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关于线性化爱因斯坦方程的边界条件


我们研究了黎曼设置中线性化爱因斯坦方程的相当大一类边界条件的性质，这些边界条件概括了安德森提出的边界条件的线性化对应项。通过寻求量子化弯曲时空引力波的棱镜，我们从椭圆率、规范不变性和光谱间隙的存在的角度研究它们的性质。