Additivity and non-additivity for perverse signatures (2009)
Friedman, Greg, Hunsicker, Eugenie
A well-known property of the signature of closed oriented 4n-dimensional manifolds is Novikov additivity, which states that if a manifold is split into two manifolds with boundary along an oriented...
Microreboot – A Technique for Cheap Recovery (2008)
George C, Shinichi Kawamoto, Yuichi Fujiki, Greg Friedman, O Fox
A significant fraction of software failures in large-scale Internet systems are cured by rebooting, even when the exact failure causes are unknown. However, rebooting can be expensive, causing...
An elementary illustrated introduction to simplicial sets (2008)
This is an expository introduction to simplicial sets and simplicial homotopy theory with particular focus on relating the combinatorial aspects of the theory to their geometric/topological origins....
On the chain-level intersection pairing for PL pseudomanifolds (2008)
James McClure recently showed that the domain for the intersection pairing of PL chains on a PL manifold $M$ is a subcomplex of $C_*(M)\otimes C_*(M)$ that is quasi-isomorphic to $C_*(M)\otimes...
Intersection homology Kunneth theorems (2008)
Cohen, Goresky and Ji showed that there is a Kunneth theorem relating the intersection homology groups $I^{\bar p}H_*(X\times Y)$ to $I^{\bar p}H_*(X)$ and $I^{\bar p}H_*(Y)$, provided that the...
Intersection homology with field coefficients: $K$-Witt spaces and $K$-Witt bordism (2008)
We construct geometric examples of pseudomanifolds that satisfy the Witt condition for intersection homology Poincare duality with respect to certain fields but not others. We also compute the...
Microreboot – A Technique for Cheap Recovery (2008)
George C, Shinichi Kawamoto, Yuichi Fujiki, Greg Friedman, O Fox
A significant fraction of software failures in large-scale Internet systems are cured by rebooting, even when the exact failure causes are unknown. However, rebooting can be expensive, causing...
Singular chain intersection homology for traditional and super-perversities (2008)
Abstract. We introduce a singular chain intersection homology theory which generalizes that of King and which agrees with the Deligne sheaf intersection homology of Goresky and MacPherson on any...
Intersection homology and Poincar\'e duality on homotopically stratified spaces (2007)
We show that intersection homology extends Poincare duality to manifold homotopically stratified spaces (satisfying mild restrictions). This includes showing that, on such spaces, the sheaf of...
Intersection homology of stratified fibrations and neighborhoods (2007)
We derive spectral sequences for the intersection homology of stratified fibrations and approximate tubular neighborhoods in manifold stratified spaces. These neighborhoods include regular...
Intersection homology of stratified fibrations and neighborhoods (2007)
We derive spectral sequences for the intersection homology of stratified fibrations and approximate tubular neighborhoods in manifold stratified spaces. These neighborhoods include regular...
Peter Bodík, Greg Friedman, Lukas Biewald, Helen Levine, George C, Kayur Patel, ...
Web applications suffer from software and configuration faults that lower their availability. Recovering from failure is dominated by the time interval between when these faults appear and when they...
A multiperversity generalization of intersection homology (2005)
We define a generalization of intersection homology based on considering a set of perversities rather than a single perversity and explore some of its properties. The question whether these...
Combining Visualization and Statistical Analysis to Improve Operator (2005)
Confidence And Efficiency, Peter Bodík, Greg Friedman, Lukas Biewald, Helen Levine, George C, ...
Web applications suffer from software and configuration faults that lower their availability. Recovering from failure is dominated by the time interval between when these faults appear and when they...
This is an introduction to the construction of higher-dimensional knots by spinning methods. Simple spinning of classical knots was introduced by E. Artin in 1926, and several generalizations have...
Some non-trivial PL knots whose complements are homotopy circles (2004)
We show that there exist non-trivial piecewise-linear (PL) knots with isolated singularities $S^{n-2}\subset S^n$, $n\geq 5$, whose complements have the homotopy type of a circle. This is in contrast...
Triangulations of 3-dimensional pseudomanifolds with an application to state-sum invariants (2004)
Banagl, Markus, Friedman, Greg
We demonstrate the triangulability of compact 3-dimensional topological pseudomanifolds and study the properties of such triangulations, including the Hauptvermutung and relations by Alexander star...
Singular chain intersection homology for traditional and super-perversities (2004)
We introduce a singular chain intersection homology theory which generalizes that of King and which agrees with the Deligne sheaf intersection homology of Goresky and MacPherson on any topological...
Superperverse intersection cohomology: stratification (in)dependence (2004)
Within its traditional range of perversity parameters, intersection cohomology is a topological invariant of pseudomanifolds. This is no longer true once one allows superperversities, in which case...
Microreboot -- A Technique for Cheap Recovery (2004)
Candea, George, Kawamoto, Shinichi, Fujiki, Yuichi, Friedman, Greg, Fox, Armando
A significant fraction of software failures in large-scale Internet systems are cured by rebooting, even when the exact failure causes are unknown. However, rebooting can be expensive, causing...
Groups of locally-flat disk knots and non-locally-flat sphere knots (2004)
The classical knot groups are the fundamental groups of the complements of smooth or piecewise-linear (PL) locally-flat knots. For PL knots that are not locally-flat, there is a pair of interesting...
Cobordism of disk knots (2004)
We study cobordisms and cobordisms rel boundary of PL locally-flat disk knots $D^{n-2}\into D^n$. Cobordisms of disk knots that do not fix the boundary sphere knots are easily classified by the...
Microreboot - A Technique for Cheap Recovery (2004)
Candea, George, Kawamoto, Shinichi, Fujiki, Yuichi, Friedman, Greg, Fox, Armando
A significant fraction of software failures in large-scale Internet systems are cured by rebooting, even when the exact failure causes are unknown. However, rebooting can be expensive, causing...
Microreboot - A Technique for Cheap Recovery (2004)
George Candea, George C, Shinichi Kawamoto, Yuichi Fujiki, Armando Fox, Greg Friedman, ...
A significant fraction of software failures in large-scale Internet systems are cured by rebooting, even when the exact failure causes are unknown. However, rebooting can be expensive, causing...
All frame-spun knots are slice (2003)
Frame-spun knots are constructed by spinning a knot of lower dimension about a framed submanifold of S^n. We show that all frame-spun knots are slice (null-cobordant).
Alexander polynomials of non-locally-flat knots (2003)
We generalize the classical study of Alexander polynomials of smooth or PL locally-flat knots to PL knots that are not necessarily locally-flat. We introduce three families of generalized Alexander...
In this paper, we develop Leray-Serre-type spectral sequences to compute the intersection homology of the regular neighborhood and deleted regular neighborhood of the bottom stratum of a stratified...
Intersection Alexander polynomials (2003)
By considering a (not necessarily locally-flat) PL knot as the singular locus of a PL stratified pseudomanifold, we can use intersection homology theory to define intersection Alexander polynomials,...