There's a minor śāstra on this topic called "chāyāpuruṣa" with texts of this name in many manuscript catalogues.  It's a component of jyotiḥśāstra.  I think it has come up in this forum before, so an archive search might turn up information.

Best,
Dominik



On Sat, 11 May 2019 at 06:26, Jonathan Silk via INDOLOGY <indology@list.indology.info> wrote:
Dear Friends,

Might anyone be aware of observations about the influence of shadows in Classical India? There is a passage in a Buddhist text that speaks of the positive influence of a dhāraṇī text which is so great that, when it is held aloft, if one were to merely pass through its shadow... So I know that this is hyperbolic, but it set me wondering if there are other references to the effect of shadows...
thanks!
Jonathan

--
J. Silk
Leiden University
Leiden University Institute for Area Studies, LIAS
Matthias de Vrieshof 3, Room 0.05b
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The Netherlands

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