Please email me if you are interested in any of the papers I haven't yet uploaded. The classification of papers below into different areas is approximate.

Talks / Surveys

ü  Inapproximability of NP-complete problems, Discrete Fourier Analysis, and Geometry  (To appear in Proc. ICM 2010).

ü  On the Unique Games Conjecture  (Proc. CCC 2010).   Powerpoint slides.

ü  FOCS’05 Tutorial.

 

PCPs and Hardness of Approximation

ü  Inapproximability of hypergraph vertex cover and applications to scheduling problems.  With Nikhil Bansal  (Submitted).

ü  Inapproximability of  vertex cover and independent set in bounded degree graphs.  With Per Austrin and Muli Safra  (Complexity 2009). 

ü  SDP gaps and UGC-hardness for MaxCutGain.   With Ryan O'Donnell (FOCS 2006).

ü  A 3-query non-adaptive PCP with perfect completeness.   With Rishi Saket. (Complexity 2006)

ü  Better inapproximability results for maxclique, chromatic number and min-3Lin-deletion.   With Ashok Kumar Ponnuswami (ICALP 2006)

ü  Hardness of approximating the closest vector problem with pre-processing.   With Misha Alekhnovich, Guy Kindler, Nisheeth Vishnoi (FOCS 2005).

ü  Hardness of Max 3SAT with no mixed clauses.   With Venkatesan Guruswami (Complexity 2005).

ü  Inapproximability results for combinatorial auctions with submodular utility functions.   With Richard J. Lipton, Evangelos Markakis, Aranyak Mehta (WINE 2005)

ü  Hardness of approximating the shortest vector problem in lattices.   (FOCS 2004, shared the Best Paper Award, invited to JACM)

ü  Ruling out PTAS for graph min-bisection, densest subgraph and bipartite clique.   (FOCS 2004, invited to SICOMP).

ü  Optimal inapproximability results for MAX-CUT and other two-variable CSPs ?   With Guy Kindler, Ryan Odonnell, Elchanan Mossel (FOCS 2004, invited to SICOMP)

ü  A new PCP outer verifier with applications to homogeneous linear equations and max-bisection.   With Jonas Holmerin (STOC 2004)

ü  Hardness of approximating the shortest vector problem in high \ell_p norms.   (FOCS 2003, Best Student Paper Award, invited to JCSS)

ü  Vertex cover might be hard to approximate within 2-\epsilon.   With Oded Regev. (Complexity 2003, invited to JCSS)

ü  A strong inapproximability gap for a generalization of minimum bisection.   With Jonas Holmerin. (Complexity 2003)

ü  A new multilayered PCP and the hardness of hypergraph vertex cover.   With Irit Dinur, Venkatesan Guruswami, Oded Regev (STOC 2003, invited to JCSS, to appear in SICOMP)

ü  Hardness of coloring 3-colorable 3-uniform hypergraphs.   (FOCS 2002)

ü  Vertex Cover on k-Uniform Hypergraphs is Hard to Approximate within Factor (k-3-\epsilon).   With Irit Dinur, Venkatesan Guruswami (ECCC Report TR02-027)

ü  Hardness results for approximate hypergraph coloring.   (STOC 2002)

ü  On the power of unique 2-prover 1-round games.   (STOC/Complexity joint session, 2002)

ü  Improved inapproximability results for maxclique, chromatic number and approximate graph coloring.   (FOCS 2001, invited to JCSS)

ü  Query efficient PCPs with perfect completeness.   With Johan Hastad (FOCS 2001)

Metric Embeddings

ü  SDP  integrality gaps with local  L1-embeddability.     With Rishi Saket (FOCS 2009). 

ü  Hardness of embedding metric spaces of equal size.   With Rishi Saket (APPROX 2007).

ü  On earthmover distance, metric labeling, and 0-extension.   With Howard Karloff, Aranyak Mehta and Yuval Rabani (STOC 2006).

ü  Integrality gaps for sparsest cut and minimum linear arrangement problems.   With Nikhil Devanur, Rishi Saket and Nisheeth Vishnoi (STOC 2006).

ü  The unique games conjecture, integrality gap for cut problems and embeddability of negative type metrics into L1.   With Nisheeth Vishnoi (FOCS 2005, shared the Best Paper Award, invited to JACM).

ü  Non-embeddability theorems via Fourier analysis.   With A.  Naor  (FOCS 2005).

Learning Theory

ü  Hardness of minimizing and learning DNF expressions.   With Rishi Saket   (FOCS 2008) .

ü  On hardness of learning intersection of two halfspaces.   With Rishi Saket   (STOC 2008) .

ü  Minimizing wide range regret with time selection functions.  With Ashok Kumar Ponnuswami.  (COLT 2008). 

ü  Hardness of reconstructing multivariate polynomials over finite fields.   With Parikshit Gopalan and Rishi Saket  (FOCS 2007, invited to SICOMP)

ü  New results for learning noisy parities and halfspaces.   With Vitaly Feldman, Parikshit Gopalan and Ashok Kumar Ponnuswami   (FOCS 2006, invited to  SICOMP)

Algorithmic Results

ü  Sharp kernel clustering algorithms and their associated Grothendieck inequalities.    With A. Naor.  (SODA 2010). 

ü  Approximate kernel clustering.  With A. Naor (FOCS 2008).

ü  Unique games on expanding constraint graphs are easy.   With Sanjeev Arora, Alexandra Kolla, David Steurer, Madhur Tulsiani, Nisheeth K. Vishnoi   (STOC 2008)

ü  Approximation algorithms for the max-min allocation problem.   With Ashok Kumar Ponnuswami.  (APPROX 2007)

ü  Linear equations modulo 2 and the L_1 diameter of convex bodies.   With A. Naor  (FOCS 2007)

Concrete Lower Bounds

ü  Cell-probe lower bounds for partial match problem.   With T.S. Jayram, S. Ravi Kumar, Yuval Rabani   (STOC 2003, invited to JCSS)

ü  Near-optimal lower bounds on the multi-party communication complexity of set-disjointness.   With Amit Chakrabarti, Xiaodong Sun (Complexity 2003)

ü  Evasiveness of subgraph containment and related properties.   With Amit Chakrabarti, Yaoyun Shi (In SICOMP, preliminary version in STACS 2001)

ü  Improved lower bounds on the randomized complexity of graph properties.   With Amit Chakrabarti (ICALP 2001)

Miscellaneous

ü  Fitting algebraic curves to noisy data.   With Sanjeev Arora (STOC 2002, invited to JCSS)

ü  Parameterized complexity of finding hereditary properties.   With Venkatesh Raman (COCOON 2000, invited to TCS)

Other Technical Writings

ü  Monotone span programs. Junior Thesis, IIT Bombay, 1998. Advisor :   Sundar Vishwanathan .

ü  Set systems with restricted intersections. Senior Thesis, IIT Bombay, 1999. Advisor : Sundar Vishwanathan.