The Equant in India: The Mathematical Basis of Ancient Indian Planetary Models

  title={The Equant in India: The Mathematical Basis of Ancient Indian Planetary Models},
  author={Dennis W. Duke},
  journal={Archive for History of Exact Sciences},
  • D. Duke
  • Published 13 April 2005
  • Archive for History of Exact Sciences
The planetary models of ancient Indian mathematical astronomy are described in several texts.1 These texts invariably give algorithms for computing mean and true longitudes of the planets, but are completely devoid of any material that would inform us of the origin of the models. One way to approach the problem is to compare the predictions of the Indian models with the predictions from other models that do have, at least in part, a known historical background. Since the Indian models compute… 
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