Intrinsic definition of the symbol of a differential operator
Discover the elegant, coordinate-free definition of differential operator symbols through a homological perspective, revealing deep connections in mathematical analysis.
The main result
Dear Reader, recently, I learnt that the symbol of a differential operator has a coordinate-free definition with a slight homological flavour. I will leave it below for a curious reader:

Please enjoy it without moderation!
Dr. Denys Dutykh
Associate Professor of Mathematics
Khalifa University of Science and Technology, Abu Dhabi, UAE
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