- On finiteness properties of the Johnson filtrations, with Sue He,
pdf
*submitted.*Revised July, 2017.

Here is an earlier version of the above paper which contains additional results on finite generation of the third and higher terms of the Johnson filtrations. Those results are not included in the submitted version and will be published elsewhere.#### Accepted papers

- Property (T) for Kac-Moody groups over rings, with Ashley Rall,
pdf

accepted by*Journal of Algebra*

#### Published papers

- Property (T) for groups graded by root systems,
with
Andrei Jaikin-Zapirain
and
Martin Kassabov,
pdf

*Memoirs of the American Mathematical Society,*249 (2017), no. 1186, vii+141 pp.

- Kazhdan groups whose FC-radical is not virtually abelian,
pdf

*Journal of Combinatorial Algebra,*2017, no. 1(1), 59-62

- The Tarski numbers of groups,
with Gili Golan and
Mark Sapir,
pdf

*Advances in Mathematics ,*2015, no. 284, 21-53

- Groups graded by root systems and property (T),
with
Andrei Jaikin-Zapirain,
Martin Kassabov and Zezhou Zhang
pdf
*Proceedings of the National Academy of Sciences ,*2014, no. 111(50), 17759-17764

- The first $L^2$-Betti number and approximation in arbitrary characteristic,
with
Wolfgang Lück,
pdf
*Documenta Mathematica ,*2014, no. 19, 313-331

- Groups of positive weighted deficiency and their applications, with Andrei Jaikin-Zapirain,
pdf
*Journal fur die reine und angewandte Mathematik ,*2013, no. 677, 71-134

- Golod-Shafarevich groups: a survey,
pdf
*International Journal of Algebra and Computation ,*2012, no. 22(5), 68 pages

- Abstract commensurators of profinite groups, with
Yiftach Barnea and
Thomas Weigel,
pdf
*Transactions of the American Mathematical Society*2011, no.363(9), 5381-5417

- Kazhdan quotients of Golod-Shafarevich groups, with appendices by
Andrei Jaikin-Zapirain,
pdf ,
*Proceedings of the London Mathematical Society*2011, no.102(4), 599-636

- The congruence subgroup property for Aut F_2: A group-theoretic proof of Asada's theorem,
with Kai-Uwe Bux and
Andrei Rapinchuk ,
pdf
*Groups, Geometry and Dynamics*2011, no.5(2), 327-353

- On the commensurator of the Nottingham group,
pdf
*Transactions of the American Mathematical Society*2010, no.362(12), 6663-6678

- Property (T) for noncommutative universal lattices, with
Andrei Jaikin-Zapirain ,
pdf
*Inventiones Mathematicae*2010, no.179(2), 303-347

- Golod-Shafarevich groups with property (T) and Kac-Moody groups,
pdf
*Duke Mathematical Journal*2008, no.145(2), 309-339

- Abstract simplicity of complete Kac-Moody groups over finite fields,
with Lisa Carbone and
Gordon Ritter,
pdf,

*Journal of Pure and Applied Algebra*2008, no. 212(10), 2147-2162

- Finite presentability of $SL_1(D)$, pdf

*Israel Journal of Mathematics*2007, no. 158, 297-347

- On subgroups of the Nottingham group of positive Hausdorff dimension, pdf

*Communications in Algebra*2007, no. 35(1), 193-206

- The Nottingham group is finitely presented, pdf
*Journal of the London Mathematical Society*2005, no. 71(2), 362-378.

- New just-infinite pro-$p$ groups of finite width and subgroups of the Nottingham group, pdf
*Journal of Algebra*2004, no. 275(1), 419-449.

- On distortion of subsemigroups,

*Moscow Univ. Bull.*1999, no. 4, 56-58.#### Old preprints

- On the second cohomology of the norm one group of a $p$-adic division algebra,
pdf
*preprint.*Revised March, 2008.