Ralph Martin Kaufmann
Purdue University; Department of Mathematics
150 N. University Street; West Lafayette, IN
 Phone: (765) 494-1205; Fax: (765) 494-0548
e-mail: rkaufman@math.purdue.edu  URL: http://www.math.purdue.edu/~rkaufman



Publications  

  1. Kaufmann, Ralph M.
    "Moduli space actions on the Hochschild cochain complex I: cell models''.
    Journal of Noncommutative Geometry 1, 3 (2007) 333-384.

  2. Jarvis, T.; Kaufmann, R. and Kimura, T.
    "Stringy K-theory and the Chern character''.
    Inventiones Math., 168, 1 (2007), 23-81

  3. Kaufmann, Ralph M.
    "On Spineless Cacti, Deligne's Conjecture and Connes-Kreimer's Hopf Algebra.''
    Topology, 46, 1 (2007), 39-88.

  4. Kaufmann, Ralph M. and  R.C. Penner.
    "Closed/open string diagrammatics".
    Nucl. Phys. B748 (2006), 3, 335-379.

  5. Kaufmann, Ralph M.
    "Singularities with Symmetries, Orbifold Frobenius algebras and Mirror Symmetry"
    Contemp. Math., 403 (2006), 67-116. (arXiv version)

  6. Jarvis, T.; Kaufmann, R and Kimura, T.
    "Pointed admissible G-covers and G-cohomological Field  theories''.
    Compositio Mathematica 141 (2005), 926-978. 

  7. Kaufmann, Ralph M.
    "On several varieties of cacti  and their relations''.
    Algebraic & Geometric Topology 5 (2005), 237–300.

  8. Kaufmann, Ralph M.
    "The algebra of discrete torsion''.
    J. of Algebra 282 (2004), 232-259.

  9. Kaufmann, Ralph M.
    "Second quantized Frobenius algebras''.
    Commun. Math. Phys. 248 (2004),  33-83.

  10. Kaufmann, Ralph M. 
    "Operads, Moduli of Surfaces and Quantum Algebras'',
    in: N. Tongring and R. C. Penner "Woods Hole Mathematics. Perspectives in Mathematics and Physics",
    Series on Knots and Everything - Vol. 34, World Scientific 2004. (ps-file)

  11. Kaufmann, Ralph M.
    "Discrete torsion, symmetric products and the Hilbert scheme",
    in:  C. Hertling and M. Marcolli (eds.) "Frobenius Manifolds, Quantum Cohomology and Singularities",
    Aspects of Mathematics E 36, Vieweg 2004. (arXiv version)

  12. Kaufmann, Ralph M.; Livernet, Muriel and Penner, Robert C. 
    "Arc Operads and Arc Algebras''.
    Geometry and Topology 7 (2003), 511-568.

  13. Kaufmann, Ralph M. 
    "Orbifolding Frobenius Algebras''. 
    Internat. J. of Math. 14 (2003), 573-619.

  14. Kaufmann, Ralph M.
    "Orbifold Frobenius Algebras, Cobordisms and Monodromies''.
    In: "Orbifolds in Mathematics and Physics'', 135-161.
    Contemp. Math. (310) . Amer. Math. Soc.,  Providence, RI, 2002.

  15. Kaufmann, Ralph M.
    "The tensor product in the theory of Frobenius manifolds''.
    Internat. J. of Math. 10 (1999), 159-206.

  16. Kaufmann, Ralph M.
    "The geometry of the moduli space of pointed curves, the tensor product
    in the theory of Frobenius manifolds and the explicit Künneth formula
    in quantum cohomology''.
    Bonner Mathematische Schriften 312, 95 p., Bonn 1997. (pdf-file)

  17.  Kaufmann, Ralph M.
    "The intersection form in H*(M0,n) and the explicit Künneth formula in quantum cohomology''.
    Internat. Math. Res. Notices 19 (1996), 929-954.

  18. Kaufmann, R.; Manin, Yu.; and Zagier, D.
    "Higher Weil-Petersson Volumes of Moduli Spaces of Stable n-pointed Curves''.
    Comm. Math. Phys. 181 (1996), 763-787.

  19. Kontsevich, M. and Manin, Yu. with appendix by R. Kaufmann.
    "Quantum cohomology of a product''.
    Invent. Math. 124 (1996), 313-339.

  20. Kaufmann, Ralph M.
    "Path Space Decompositions for the Virasoro Algebra and its Verma Modules''.
    Internat. J. of Modern Phys. A 10 (1995), 943-961. 

Accepted for Publication  

  1. Kaufmann, Ralph M.
    "Graphs, strings and actions"
      in Manin Festschrift., 51p, to appear.
       Final version, Preprint  MPIM 2007-95.

  2. Kaufmann, Ralph M.
    "Noncommutative aspects of open/closed strings via foliations"
      Reports on Math. Phys., to appear.

  3. Kaufmann, Ralph M.
    "Moduli space actions on the Hochschild cochain complex II: correlators''.
    Preprint,  math.AT/0606065,   MPIM2006-119, 50p,
    Journal of Noncommutative Geometry to appear

  4. Kaufmann, Ralph M.
    "Dimension vs. Genus: A surface realization of the little k-cubes and an E_{\infty} operad."
    Preprint, arXiv:0801.0532, 35p.
    in: Conference proceedings of the Postnikov Memorial Conference, Bedlewo 2007, to appear

  5. Kaufmann, Ralph M. and Pham, David
    "The Drinfel'd Double and Twisting in Stringy Orbifold Theory".
    Preprint, arXiv:0708.4006, MPIM2007-104, IML No.40 2006/07, 35p.
    International Journal of Mathematics to appear.

Submitted Preprints

  1. Kaufmann, Ralph M.
    "A proof of a cyclic version of Deligne's conjecture via Cacti"
    Preprint,  math.QA/0403340, 20p.

  2. Kaufmann, Ralph M.
    "A Note on the Two Approaches to Stringy Functors for Orbifolds''.
    Preprint,  math.AG/0703209, MPIM 2007-96, 16p.

  3. Kaufmann, Ralph M. and Schwell, Rachel
    "Associahedra, Cyclohedra and a Topological solution to the A_{\infty}--Deligne conjecture"
    Preprint, arXiv:0710.3967, 36p. 

In Preparation

  1. Jarvis, T.; Kaufmann, R and Kimura, T.
    "G-equivariant Gromov Witten Invariants''

  2. Kaufmann, Ralph M.
    "The Arc spectrum: Detecting Loop spaces with the Arc operad"