A new derivation of singularity theorems with weakened energy hypotheses

  title={A new derivation of singularity theorems with weakened energy hypotheses},
  author={Christopher J. Fewster and Eleni-Alexandra Kontou},
  journal={Classical and Quantum Gravity},
The original singularity theorems of Penrose and Hawking were proved for matter obeying the Null Energy Condition or Strong Energy Condition respectively. Various authors have proved versions of these results under weakened hypotheses, by considering the Riccati inequality obtained from Raychaudhuri's equation. Here, we give a different derivation that avoids the Raychaudhuri equation but instead makes use of index form methods. We show how our results improve over existing methods and how they… 

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