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arXiv · 1801.05308

Some binomial formulas for non-commuting operators

Peter Kuchment·Sergey Lvin
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Abstract

Let $D$ and $U$ be linear operators in a vector space (or more generally, elements of an associative algebra with a unit). We establish binomial-type identities for $D$ and $U$ assuming that either their commutator $[D,U]$ or the second commutator $[D,[D,U]]$ is proportional to $U$. Operators $D=d/dx$ (differentiation) and $U$- multiplication by $e^{λx}$ or by $\sin λx$ are basic examples, for which some of these relations appeared unexpectedly as byproducts of an authors' previous medical imaging research.

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Peter Kuchment, Sergey Lvin. 2018-01-14. Some binomial formulas for non-commuting operators. https://arxiv.org/abs/1801.05308

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