Abstract
As a desert, we serve a number of open problems connected with the subject matter of the book. Some of them consider the general framework of spectral triples and its possible extensions, while the other are more specific and relate to the properties of the spectral action. The problems are essentially of mathematical nature, though, at least in some cases, the conceptual skeleton strongly depends upon the input from physics. To our mind, the solution to each of these stumbling blocks would advance our understanding of the foundations and implications of the Spectral Action Principle. We therefore cordially invite the Reader to contemplate the list below, both from mathematical and physical perspectives.
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Eckstein, M., Iochum, B. (2018). Open Problems. In: Spectral Action in Noncommutative Geometry. SpringerBriefs in Mathematical Physics, vol 27. Springer, Cham. https://doi.org/10.1007/978-3-319-94788-4_5
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