## Rhombic tilings and Bott–Samelson varieties

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- by Laura Escobar, Oliver Pechenik, Bridget Eileen Tenner and Alexander Yong PDF
- Proc. Amer. Math. Soc.
**146**(2018), 1921-1935 Request permission

## Abstract:

S. Elnitsky (1997) gave an elegant bijection between rhombic tilings of $2n$-gons and commutation classes of reduced words in the symmetric group on $n$ letters. P. Magyar (1998) found an important construction of the Bott–Samelson varieties introduced by H. C. Hansen (1973) and M. Demazure (1974). We explain a natural connection between S. Elnitsky’s and P. Magyar’s results. This suggests using tilings to encapsulate Bott–Samelson data (in type $A$). It also indicates a geometric perspective on S. Elnitsky’s bijection. We also extend this construction by assigning desingularizations of Schubert varieties to the zonotopal tilings considered by B. Tenner (2006).## References

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## Additional Information

**Laura Escobar**- Affiliation: Department of Mathematics, University of Illinois at Urbana–Champaign, Urbana, Illinois 61801
- MR Author ID: 990678
- ORCID: 0000-0002-7970-4152
- Email: lescobar@illinois.edu
**Oliver Pechenik**- Affiliation: Department of Mathematics, Rutgers University, Piscataway, New Jersey 08854
- Address at time of publication: Department of Mathematics, University of Michigan, Ann Arbor, Michigan 48109
- MR Author ID: 863417
- ORCID: 0000-0002-7090-2072
- Email: pechenik@umich.edu
**Bridget Eileen Tenner**- Affiliation: Department of Mathematical Sciences, DePaul University, Chicago, Illinois 60614
- MR Author ID: 776323
- Email: bridget@math.depaul.edu
**Alexander Yong**- Affiliation: Department of Mathematics, University of Illinois at Urbana–Champaign, Urbana, Illinois 61801
- MR Author ID: 693975
- Email: ayong@uiuc.edu
- Received by editor(s): July 13, 2016
- Received by editor(s) in revised form: July 6, 2017
- Published electronically: December 26, 2017
- Additional Notes: The second author was supported by an NSF Graduate Research Fellowship.

The third author was partially supported by a Simons Foundation Collaboration Grant for Mathematicians.

The fourth author was supported by an NSF grant. - Communicated by: Patricia Hersh
- © Copyright 2017 American Mathematical Society
- Journal: Proc. Amer. Math. Soc.
**146**(2018), 1921-1935 - MSC (2010): Primary 05B45, 05E15, 14M15
- DOI: https://doi.org/10.1090/proc/13869
- MathSciNet review: 3767346