Lorentzian polynomials from polytope projections
Algebraic Combinatorics, Volume 4 (2021) no. 4, pp. 723-739.

Lorentzian polynomials, recently introduced by Brändén and Huh, generalize the notion of log-concavity of sequences to homogeneous polynomials whose supports are integer points of generalized permutahedra. Brändén and Huh show that normalizations of integer point transforms of generalized permutahedra are Lorentzian. Moreover, normalizations of certain projections of integer point transforms of generalized permutahedra with zero-one vertices are also Lorentzian. Taking this polytopal perspective further, we show that normalizations of certain projections of integer point transforms of flow polytopes are Lorentzian.

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DOI: https://doi.org/10.5802/alco.179
Classification: 05E99,  05A20
Keywords: Lorenztian polynomial, flow polytope, integer point transforms.
@article{ALCO_2021__4_4_723_0,
     author = {M\'esz\'aros, Karola and Setiabrata, Linus},
     title = {Lorentzian polynomials from polytope projections},
     journal = {Algebraic Combinatorics},
     pages = {723--739},
     publisher = {MathOA foundation},
     volume = {4},
     number = {4},
     year = {2021},
     doi = {10.5802/alco.179},
     language = {en},
     url = {https://alco.centre-mersenne.org/articles/10.5802/alco.179/}
}
Mészáros, Karola; Setiabrata, Linus. Lorentzian polynomials from polytope projections. Algebraic Combinatorics, Volume 4 (2021) no. 4, pp. 723-739. doi : 10.5802/alco.179. https://alco.centre-mersenne.org/articles/10.5802/alco.179/

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