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JOURNAL OF
ALGEBRAIC
COMBINATORICS

  Editors-in-chief: C. A. Athanasiadis, T. Lam, A. Munemasa, H. Van Maldeghem
ISSN 0925-9899 (print) • ISSN 1572-9192 (electronic)
 

Geometric complexity theory III: on deciding nonvanishing of a Littlewood-Richardson coefficient

Ketan D. Mulmuley1 , Hariharan Narayanan2 and Milind Sohoni3
1Department of Computer Science, University of Chicago, 1100 E 58th Street, Chicago, IL 60637, USA
2Laboratory for Information and Decision Systems, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
3Department of Computer Science and Engineering, Indian Institute of Technology Bombay, Mumbai, 400 076 India

DOI: 10.1007/s10801-011-0325-1

Abstract

We point out that the positivity of a Littlewood-Richardson coefficient _boxclose_boxclose_, c^{γ}_{α, β} for sl n can be decided in strongly polynomial time. This means that the number of arithmetic operations is polynomial in n and independent of the bit lengths of the specifications of the partitions α , β , and γ , and each operation involves numbers whose bitlength is polynomial in n and the bit lengths α , β , and γ .

Pages: 103–110

Keywords: keywords Littlewood-richardon coefficients; geometric complexity theory; algorithms

Full Text: PDF

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