Proceedings 41st Annual Symposium on Foundations of Computer Science

12-14 Nov. 2000

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  • Proceedings 41st Annual Symposium on Foundations of Computer Science

    Publication Year: 2000
    Request permission for commercial reuse | PDF file iconPDF (259 KB)
    Freely Available from IEEE
  • Private quantum channels

    Publication Year: 2000, Page(s):547 - 553
    Cited by:  Papers (25)  |  Patents (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (571 KB)

    We investigate how a classical private key can be used by two players, connected by an insecure one-way quantum channel, to perform private communication of quantum information. In particular, we show that in order to transmit n qubits privately, 2n bits of shared private key are necessary and sufficient. This result may be viewed as the quantum analogue of the classical one-time pad encryption sc... View full abstract»

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  • The cover time, the blanket time, and the Matthews bound

    Publication Year: 2000, Page(s):467 - 475
    Cited by:  Papers (7)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (500 KB)

    We prove upper and lower bounds and give an approximation algorithm for the cover time of the random walk on a graph. We introduce a parameter M motivated by the well-known Matthews bounds (P. Matthews, 1988) on the cover time, C, and prove that M/2<C= O(M(lnlnn)2 ). We give a deterministic-polynomial time algorithm to approximate M within a factor of 2; this then approximates C with... View full abstract»

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  • The common fragment of CTL and LTL

    Publication Year: 2000, Page(s):643 - 652
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (756 KB)

    It is well-known that CTL (computation tree logic) and LTL (linear time logic) have incomparable expressive power. In this paper, we give an inductive definition of those ACTL (Action-based CTL) formulas that can be expressed in LTL. In addition, we obtain a procedure to decide whether an ACTL formula lies in LTL, and show that this problem is PSPACE-complete. By omitting path quantifiers, we get ... View full abstract»

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  • Topological persistence and simplification

    Publication Year: 2000, Page(s):454 - 463
    Cited by:  Papers (52)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (868 KB)

    We formalize a notion of topological simplification within the framework of a filtration, which is the history of a growing complex. We classify a topological change that happens during growth as either a feature or noise, depending on its life-time or persistence within the filtration. We give fast algorithms for completing persistence and experimental evidence for their speed and utility View full abstract»

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  • Combinatorial feature selection problems

    Publication Year: 2000, Page(s):631 - 640
    Cited by:  Papers (5)  |  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (888 KB)

    Motivated by frequently recurring themes in information retrieval and related disciplines, we define a genre of problems called combinatorial feature selection problems. Given a set S of multidimensional objects, the goal is to select a subset K of relevant dimensions (or features) such that some desired property Π holds for the set S restricted to K. Depending on Π, the goal could be to eit... View full abstract»

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  • Stable distributions, pseudorandom generators, embeddings and data stream computation

    Publication Year: 2000, Page(s):189 - 197
    Cited by:  Papers (44)  |  Patents (20)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (568 KB)

    In this paper we show several results obtained by combining the use of stable distributions with pseudorandom generators for bounded space. In particular: we show how to maintain (using only O(log n/ε2) words of storage) a sketch C(p) of a point p∈l1n under dynamic updates of its coordinates, such that given sketches C(p) and C(q) one can estimate |p-q| View full abstract»

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  • A combinatorial approach to planar non-colliding robot arm motion planning

    Publication Year: 2000, Page(s):443 - 453
    Cited by:  Papers (14)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (960 KB)

    We propose a combinatorial approach to plan noncolliding motions for a polygonal bar-and-joint framework. Our approach yields very efficient deterministic algorithms for a category of robot arm motion planning problems with many degrees of freedom, where the known general roadmap techniques would give exponential complexity. It is based on a novel class of one-degree-of-freedom mechanisms induced ... View full abstract»

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  • An improved quantum Fourier transform algorithm and applications

    Publication Year: 2000, Page(s):515 - 525
    Cited by:  Papers (13)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (684 KB)

    We give an algorithm for approximating the quantum Fourier transform over an arbitrary Zp which requires only O(n log n) steps where n=log p to achieve an approximation to within an arbitrary inverse polynomial in n. This improves the method of A.Y. Kitaev (1995) which requires time quadratic in n. This algorithm also leads to a general and efficient Fourier sampling technique which imp... View full abstract»

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  • Cache-oblivious B-trees

    Publication Year: 2000, Page(s):399 - 409
    Cited by:  Papers (12)  |  Patents (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1008 KB)

    We present dynamic search-tree data structures that perform well in the setting of a hierarchical memory (including various levels of cache, disk, etc.), but do not depend on the number of memory levels, the block sizes and number of blocks at each level, or the relative speeds of memory access. In particular between any pair of levels in the memory hierarchy, where transfers between the levels ar... View full abstract»

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  • Cost-distance: two metric network design

    Publication Year: 2000, Page(s):624 - 630
    Cited by:  Papers (27)  |  Patents (5)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (580 KB)

    Presents the cost-distance problem, which consists of finding a Steiner tree which optimizes the sum of edge costs along one metric and the sum of source-sink distances along an unrelated second metric. We give the first known O(log k) randomized approximation scheme for the cost-distance problem, where k is the number of sources. We reduce several common network design problems to cost-distance p... View full abstract»

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  • Randomized rumor spreading

    Publication Year: 2000, Page(s):565 - 574
    Cited by:  Papers (180)  |  Patents (15)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (844 KB)

    Investigates the class of epidemic algorithms that are commonly used for the lazy transmission of updates to distributed copies of a database. These algorithms use a simple randomized communication mechanism to ensure robustness. Suppose n players communicate in parallel rounds in each of which every player calls a randomly selected communication partner. In every round, players can generate rumor... View full abstract»

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  • Straightening polygonal arcs and convexifying polygonal cycles

    Publication Year: 2000, Page(s):432 - 442
    Cited by:  Papers (8)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (992 KB)

    Consider a planar linkage, consisting of disjoint polygonal arcs and cycles of rigid bars joined at incident endpoints (polygonal chains), with the property that no cycle surrounds another arc or cycle. We prove that the linkage can be continuously moved so that the arcs become straight, the cycles become convex, and no bars cross while preserving the bar lengths. Furthermore, our motion is piecew... View full abstract»

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  • Testing of function that have small width branching programs

    Publication Year: 2000, Page(s):251 - 258
    Cited by:  Papers (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (572 KB)

    Combinatorial property testing, initiated formally by (Goldreich et al., 1996) and inspired by (Rubinfeld and Sudan, 1996), deals with the following relaxation of decision problems: given a fixed property and an input x, one wants to decide whether x has the property or is being far from having the property. The main result here is that if G={g:{0,1}n→{0,1}} is a family of Boolean ... View full abstract»

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  • The randomness recycler: a new technique for perfect sampling

    Publication Year: 2000, Page(s):503 - 511
    Cited by:  Papers (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (724 KB)

    For many probability distributions of interest, it is quite difficult to obtain samples efficiently. Often, Markov chains are employed to obtain approximately random samples from these distributions. The primary drawback to traditional Markov chain methods is that the mixing time of the chain is usually unknown, which makes it impossible to determine how close the output samples are to having the ... View full abstract»

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  • Opportunistic data structures with applications

    Publication Year: 2000, Page(s):390 - 398
    Cited by:  Papers (172)  |  Patents (4)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (844 KB)

    We address the issue of compressing and indexing data. We devise a data structure whose space occupancy is a function of the entropy of the underlying data set. We call the data structure opportunistic since its space occupancy is decreased when the input is compressible and this space reduction is achieved at no significant slowdown in the query performance. More precisely, its space occupancy is... View full abstract»

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  • Building Steiner trees with incomplete global knowledge

    Publication Year: 2000, Page(s):613 - 623
    Cited by:  Papers (14)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (864 KB)

    A networking problem of present-day interest is that of distributing a single data item to multiple clients while minimizing network usage. Steiner tree algorithms are a natural solution method, but only when the set of clients requesting the data is known. We study what can be done without this global knowledge, when a given vertex knows only the probability that any other client wishes to be con... View full abstract»

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  • On the hardness of graph isomorphism

    Publication Year: 2000, Page(s):180 - 186
    Cited by:  Papers (4)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (532 KB)

    We show that the graph isomorphism problem is hard under logarithmic space many-one reductions for the complexity classes NL, PL (probabilistic logarithmic space), for every logarithmic space modular class ModkL and for the class DET of problems NC1 reducible to the determinant. These are the strongest existing hardness results for the graph isomorphism problem, and imply a r... View full abstract»

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  • On levels in arrangements of curves

    Publication Year: 2000, Page(s):219 - 227
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (684 KB)

    Analyzing the worst-case complexity of the k-level in a planar arrangement of n curves is a fundamental problem in combinatorial geometry. We give the first subquadratic upper bound (roughly O(nk1-2/3*)) for curves that are graphs of polynomial functions of an arbitrary fixed degree s. Previously, nontrivial results were known only for the case s=1 and s=2. We also improve the earlier b... View full abstract»

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  • Existential second-order logic over graphs: charting the tractability frontier

    Publication Year: 2000, Page(s):664 - 674
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1116 KB)

    Fagin's (1974) theorem, the first important result of descriptive complexity, asserts that a property of graphs is in NP if and only if it is definable by an existential second-order formula. We study the complexity of evaluating existential second-order formulas that belong to prefix classes of existential second-order logic, where a prefix class is the collection of all existential second-order ... View full abstract»

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  • Succinct quantum proofs for properties of finite groups

    Publication Year: 2000, Page(s):537 - 546
    Cited by:  Papers (21)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (808 KB)

    The article considers a quantum computational variant of nondeterminism based on the notion of a quantum proof, which is a quantum state that plays a role similar to a certificate in an NP-type proof. Specifically, we consider quantum proofs for properties of black-box groups, which are finite groups whose elements are encoded as strings of a given length and whose group operations are performed b... View full abstract»

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  • On the boundary complexity of the union of fat triangles

    Publication Year: 2000, Page(s):423 - 431
    Cited by:  Papers (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (624 KB)

    A triangle is said to be δ-fat if its smallest angle is at least δ>0. A connected component of the complement of the union of a family of triangles is called hole. It is shown that any family of δ-far triangles in the plane determines at most O (n/δ log 2/δ) holes. This improves on some earlier bounds of (Efrat et al., 1993; Matousek et al., 1994). Solving a proble... View full abstract»

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  • Testing of clustering

    Publication Year: 2000, Page(s):240 - 250
    Cited by:  Papers (5)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (860 KB)

    A set X of points in ℜd is (k,b)-clusterable if X can be partitioned into k subsets (clusters) so that the diameter (alternatively, the radius) of each cluster is at most b. We present algorithms that by sampling from a set X, distinguish between the case that X is (k,b)-clusterable and the case that X is ε-far from being (k,b')-clusterable for any given 0<ε⩽1 and f... View full abstract»

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  • On the approximability of trade-offs and optimal access of Web sources

    Publication Year: 2000, Page(s):86 - 92
    Cited by:  Papers (66)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (600 KB)

    We study problems in multiobjective optimization, in which solutions to a combinatorial optimization problem are evaluated with respect to several cost criteria, and we are interested in the trade-off between these objectives (the so-called Pareto curve). We point out that, under very general conditions, there is a polynomially succinct curve that ε-approximates the Pareto curve, for any ^... View full abstract»

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  • Optimization problems in congestion control

    Publication Year: 2000, Page(s):66 - 74
    Cited by:  Papers (15)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (684 KB)

    One of the crucial elements in the Internet's success is its ability to adequately control congestion. The paper defines and solves several optimization problems related to Internet congestion control, as a step toward understanding the virtues of the TCP congestion control algorithm currently used and comparing it with alternative algorithms. We focus on regulating the rate of a single unicast fl... View full abstract»

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