Mathematics
Research Interests:
My research is in a field known as 'higher-dimensional algebra.' My dissertation, Lie 2-Algebras, was written under the guidance of John Baez. My work blends Lie theory with elements of category theory and has connections to braid theory and Lie algebra cohomology. I am also interested in the relationship between Lie algebras and algebraic structures known as quandles. Thus, my interests lie in quantum algebra and quantum and geometric topology.
In my dissertation, I defined and explored generalized Lie algebras, called 'Lie 2-algebras,' and classified them up to equivalence in terms of Lie algebra cohomology. A Lie 2-algebra is a category equipped with algebraic structure much like that of a Lie algebra, but where the laws involving the bracket only hold up to isomorphism. In my dissertation, I focused on semistrict Lie 2-algebras which are those where only the Jacobi identity fails to hold as an equation. I showed that just as any Lie algebra gives a solution of the Yang-Baxter equation, a semistrict Lie 2-algebra gives a solution of the Zamolodchikov tetrahedron equation, which is the higher dimensional analog of the Yang-Baxter equation. Furthermore, I explored the relationship between groups, Lie algebras, quandles, and braids, and described a novel means of passing from a Lie group to its Lie algebra.
To learn more about my work, please read (pdf versions of) my:
And if you're feeling ambitious:
- My Dissertation: Lie 2-Algebras
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Publications:
- Crans, A.; Henrich, A.; and Nelson, S. "Knot and link invariants from the Alexander virtual biquandle." Submitted to the Journal of Knot Theory and its Ramifications in October 2011. Available as arXiv:1110.1371.
- Crans, A.; Nelson, S.; and Sarkar, A. "Enhancements of the rack counting invariant via N-reduced dynamical cocycles." Submitted to the Osaka Journal of Mathematics in August 2011. Available as arXiv:1108.4387.
- Crans, A.; and Rovetti, R. "Beyond Formulas: A Collaboration between Liberal Arts Honors Underclassmen and Senior Math Majors". Honors in Practice Vol 7 (2011): 115 - 126.
- Carter, J.S.; Crans, A.; Elhamdadi, M.; and Saito, M. "Cocycle Deformations of Algebraic Identities and R-matrices." Available as arXiv:0802.2294.
- Crans, A.; Fiore, T.; and Satyendra, R. "Musical Actions of Dihedral Groups." The American Mathematical Monthly, Vol. 116 (2009), No. 6: 479 - 495. Also available as arXiv:0711.1873.
- Carter, J.S.; Crans, A.; Elhamdadi, M.; Karadayi, E.; and Saito, M. "Cohomology of Frobenius Algebras and the Yang-Baxter Equation." Communications in Contemporary Mathematics Vol. 10 (2008), No. 1 supp: 791 - 814. Also available as arXiv:0801.2567.
- Carter, J.S.; Crans, A.; Elhamdadi, M.; and Saito, M. "Cohomology of Categorical Self-Distributivity." Journal of Homotopy and Related Structures Vol 3. (2008), No. 1: 13 - 63. Also available as arXiv:math/0607417.
- Carter, J.S.; Crans, A.; Elhamdadi, M.; and Saito, M. " Cohomology of the adjoint of Hopf algebras." Journal of Generalized Lie Theory and Applications Vol. 2 (2008), No. 1: 19 - 34. Also available as arXiv:0705.3231.
- Baez, J; Crans, A.; and Wise, D. "Exotic Statistics for Loops in 4d BF Theory". Advances in Theoretical and Mathematical Physics Vol. 11 (2007), No 11: 707 - 749. Also available as arXiv:gr-qc/0603085.
- Baez, J.; Crans, A.; Schrieber, U.; and Stevenson, D. "Loop Groups to 2-Groups" Homology, Homotopy, and its Applications Vol. 9 (2007), No. 2: 101 - 135. Also available as arXiv:math/0504123.
- Baez, J.; and Crans, A. "Higher Dimensional Algebra VI: Lie 2-Algebras". Theory and Applications of Categories. 12 (2004), 492-538. Also available as arXiv:math/0307263.
- Crans, A.; Fallat, S.; and Johnson, C. "The Hadamard Core of the Totally Nonnegative Matrices." Linear Algebra and its Applications. 328 (2001), 203 - 222.
- Crans, A.; and Weinhold, R. "What to Do on Your Summer Vacation." Math Horizons. February 2001, 23 - 26.
Examples of final student projects resulting from this collaboration include recreations of photographs of Sacred Heart Chapel and St. Robert's Hall. Original music (Copyright 2011) for each of these was composed by Mike Hyziak and Eleni Maureas, EMMPH.
This paper was awarded the 2011 Merten M. Hasse Prize by the Mathematical Association of America as a "noteworthy expository paper appearing in an Association publication."
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Selected Grants:
- Cameron, N.; Crans, A.; and Killpatrick, K. Pacific Coast Undergraduate Mathematics Conferences 2012, NSF Mathematical Sciences Infrastructure Program, $23,056
- Cameron, N.; Crans, A.; and Killpatrick, K. Pacific Coast Undergraduate Mathematics Conference 2011, National Security Agency Conference/Workshop Grant $10,000
- Crans, A. Categorified Quandles, National Security Agency Young Investigator's Grant, Summers 2010 and 2011, $29,709
- Cameron, N.; Crans, A.; and Killpatrick, K. Pacific Coast Undergraduate Mathematics Conference 2010, MAA undergraduate conferences NSF Grant DMS-0241090 $3,500
- Cameron, N.; Crans, A.; and Killpatrick, K. Pacific Coast Undergraduate Mathematics Conference 2009, National Security Agency Conference/Workshop Grant $15,000; MAA Undergraduate Conferences NSF Grant DMS-0241090 $2,500
- Cameron, N.; Crans, A.; and Killpatrick, K. Pacific Coast Undergraduate Mathematics Conference 2008 National Security Agency Conference/Workshop Grant, $14,650; MAA Undergraduate Conferences NSF Grant DMS-0241090 $3,000; Raytheon $2,000
- Crans, A.; DeCoste, R.; and Stewart, S.A. Career Mentoring Workshop for Women MAA TENSOR Grant $6,000
- Cameron, N.; Crans, A.; and Killpatrick, K. Pacific Coast Undergraduate Mathematics Conference 2007 MAA Undergraduate Conferences NSF Grant DMS-0241090 $3,000
- Cameron, N.; Crans, A.; and Killpatrick, K. Pacific Coast Undergraduate Mathematics Conference 2006 MAA Undergraduate Conferences NSF Grant DMS-0241090 $2,500
- Crans, A. AWM Travel Grant to attend Categories in Algebra, Geometry, and Mathematical Physics Conference at Macquarie University, July 2005, $1,257
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Selected Presentations:
(for a complete list, please see my Curriculum Vitae)
- "Cracking the Cubic: Cardano, Controversy, and Creasing," Invited Speaker, MAA DC-MD-VA Spring Section Meeting, Stevenson University, April 2012
- "Patterns + Women = Figures in Mathematics," Keynote Speaker, Expanding Your Horizons, James Madison University, March 2012
- "Hom Quandles," AMS Special Session on Homology Theories Motivated by Knot Theory, AMS Spring Sectional Meeting, George Washington University, March 2012
- "Torsion in One Term Distributive Homology," Knots in Washington XXIV Conference, George Washington University, March 2012
- "A Surreptitious Sequence: the Catalan Numbers," Invited Speaker, MAA EPaDel Fall Section Meeting, Bryn Mawr College, November 2011
- "Count Me In!," Alder Award Presentation, Mathfest 2011, Lexington, Kentucky, August 2011
- "Million Dollar Mathematics," Keynote Speaker, Southern California Undergraduate Math Day, University of California, San Diego, April 2011
- "Pascal's Patterns," Keynote Speaker, University of Oklahoma Math Day, November 2010
- "Categorical Quandles and Knots I--Definition and Examples," Algebraic Structures in Knot Theory, AMS Sectional Meeting, UCLA, October 2010
- "Musical Actions of Dihedral Groups," Invited Speaker, MAA So Cal-Nev Spring Section Meeting, Harvey Mudd College, April 2010
- "Loop Groups and Lie 2-Algebras," Max Planck Institute for Mathematics, June 2009
- "Algebraic Categorification," Invariants in Low-Dimensional Topology, Mathematisches Forschungsinstitut Oberwolfach, May 2008
- "2-Quandles," Recent Advances in Knot Theory: Quandle Theory and Categorified Knot Invariants, AMS Sectional Meeting, LSU, March 2008
- "R,C,H,O," Summer Program for Women in Mathematics, The George Washington University, July 2007
- "Meet the 3-sphere," with Liz Stanhope, SMPosium, Summer Mathematics Program for Women Undergraduates, Carleton College, June 2007
- "A Survey of Higher Lie Theory," Higher Categories and Their Applications, Fields Institute, Toronto, Canada, January 2007
- "Categorical Self-Distributivity," AWM Workshop, Joint Mathematics Meetings, New Orleans, January 2007
- "Quandle Queries," Opening Address, Knots in Washington XXIII, George Washington University, Washington, DC, November 2006
- "Lie 2-Groups, Lie 2-Algebras, and Loop Groups," Midwest Topology Seminar/Category Theory and its Applications Conference in memory of Saunders Mac Lane, University of Chicago, April 2006
- "Higher-Dimensional Algebra: Weakening the Notion of Equality," Invitation to Research Seminar, The Ohio State University, January 2006
- "Loop Groups and Lie 2-Algebras," Categories in Algebra, Geometry and Mathematical Physics Conference, Macquarie University, July 2005
- "2-Braids, 2-Groups, and Lie 2-Algebras," Quantum Topology--Contemporary Issues and Perspectives Conference, Snowbird, UT, June 2005
- "Matrix Groups: Where Symmetry meets Geometry," Minicourse for EDGE (Enhancing Diversity in Graduate Education) Program for women, North Carolina A & T State, June 2005
- "Solutions of the Yang-Baxter and Zamolodchikov Tetrahedron Equations," Braid Groups and Applications Conference, Banff Research Center (BIRS), October 2004
- "Higher Linear Algebra," n-Categories: Foundations and Applications Conference, Institute for Mathematics and its Applications, June 2004
- "Lie 2-Algebras," AWM Workshop Poster Presentation, Joint Mathematics Meetings, Phoenix, January 2004
- "Braids and the Yang-Baxter Equation: An Application of Knot Theory to Physics," MAA Invited Paper Session on Applications of Topology to Biology, Chemistry, and Physics, Joint Mathematics Meetings, Phoenix, January 2004
This talk was presented after being honored with the Henry L. Alder Award for "Distinguished Teaching by a Beginning College/University Mathematics Faculty Member" by the Mathematical Association of America.
(Please e-mail me if you would like the musical tracks to accompany this talk.)
This talk concluded a series of three talks on Higher Gauge Theory in which John Baez, Danny Stevenson, and I presented the results of our paper, "Loop Groups to 2-Groups." Our abstracts and slides are available here.
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Fun Stuff:
- My other mathematical interests include algebraic coding theory, knot theory, the history of mathematics, and the relationship between music and mathematics. Here's an excellent site for math history.
- My advisor's advisor's advisor's advisor's advisor's advisor's advisor's advisor's advisor was Gauss! Of course you can trace my mathematical lineage using The Mathematics Genealogy Project, but it's more fun to read the whole story as told by my advisor, John Baez, in Week 166 of his column This Week's Finds in Mathematical Physics.
- My Erdos number is 3, which I determined using the Erdos Number Project. My Bacon number is 2. Thus, my Erdos-Bacon number is 5.
- Did you see that my advisor is running for president in 2024? Not as exciting, but still fun: he was honored with the title of Geek O' the Week in April 2005.
- And...who doesn't love a fun math comic?
- Did you hear? I was Time's 2006 Person of the Year!