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arXiv · 1904.12458

5d Dirac fermion on quantum graph

Yukihiro Fujimoto·Tomonori Inoue·Makoto Sakamoto·Kazunori Takenaga·Inori Ueba
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Abstract

In this paper, we investigate a five-dimensional Dirac fermion on a quantum graph that consists of a single vertex and $N$ loops. We find that the model possesses a rich structure of boundary conditions for wavefunctions on the quantum graph and they can be classified into $(2N+1)$ distinct categories. It is then shown that there appear degenerate four-dimensional chiral massless fermions in the four-dimensional mass spectrum. We briefly discuss how our model could naturally solve the problems of the fermion generation, the fermion mass hierarchy and the origin of the $CP$-violating phase.

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Yukihiro Fujimoto, Tomonori Inoue, Makoto Sakamoto, Kazunori Takenaga, Inori Ueba. 2019-04-29. 5d Dirac fermion on quantum graph. https://doi.org/10.1088/1751-8121%2Fab4859

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