Imperial College London

Professor Richard Thomas FRS

Faculty of Natural SciencesDepartment of Mathematics

Royal Society Research Professor (Pure Mathematics)
 
 
 
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Contact

 

richard.thomas Website

 
 
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Location

 

659Huxley BuildingSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Thomas:2020:10.1007/s00220-020-03821-1,
author = {Thomas, RP},
doi = {10.1007/s00220-020-03821-1},
journal = {Communications in Mathematical Physics},
pages = {1451--1500},
title = {Equivariant K-theory and refined Vafa-Witten invariants},
url = {http://dx.doi.org/10.1007/s00220-020-03821-1},
volume = {378},
year = {2020}
}

RIS format (EndNote, RefMan)

TY  - JOUR
AB - In [MT2] the Vafa-Witten theory of complex projective surfaces is lifted tooriented $\mathbb C^$-equivariant cohomology theories. Here we study theK-theoretic refinement. It gives rational functions in $t^{1/2}$ invariantunder $t^{1/2}\leftrightarrow t^{-1/2}$ which specialise to numericalVafa-Witten invariants at $t=1$. On the "instanton branch" the invariants give the virtual$\chi_{-t}^{}$-genus refinement of G\"ottsche-Kool. Applying modularity totheir calculations gives predictions for the contribution of the "monopolebranch". We calculate some cases and find perfect agreement. We also docalculations on K3 surfaces, finding Jacobi forms refining the usual modularforms, proving a conjecture of G\"ottsche-Kool. We determine the K-theoretic virtual classes of degeneracy loci usingEagon-Northcott complexes, and show they calculate refined Vafa-Witteninvariants. Using this Laarakker [Laa] proves universality results for theinvariants.
AU - Thomas,RP
DO - 10.1007/s00220-020-03821-1
EP - 1500
PY - 2020///
SN - 0010-3616
SP - 1451
TI - Equivariant K-theory and refined Vafa-Witten invariants
T2 - Communications in Mathematical Physics
UR - http://dx.doi.org/10.1007/s00220-020-03821-1
UR - http://arxiv.org/abs/1810.00078v3
UR - http://hdl.handle.net/10044/1/80114
VL - 378
ER -