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Results 11 - 20
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34,476
MOMENT GENERATING FUNCTIONS AND FURTHER EXACT RESULTS FOR
, 2016
"... and further exact results for seasonal autoregressions ..."
Exact Matrix Completion via Convex Optimization
, 2008
"... We consider a problem of considerable practical interest: the recovery of a data matrix from a sampling of its entries. Suppose that we observe m entries selected uniformly at random from a matrix M. Can we complete the matrix and recover the entries that we have not seen? We show that one can perfe ..."
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Cited by 873 (26 self)
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by solving a simple convex optimization program. This program finds the matrix with minimum nuclear norm that fits the data. The condition above assumes that the rank is not too large. However, if one replaces the 1.2 exponent with 1.25, then the result holds for all values of the rank. Similar results hold
Bandgap Extremization: Some Exact Results
, 2008
"... We present here a variational method for maximizing the bandgap in a one-dimensional system where the potential is subject to given constraints. Two specific examples are studied in detail. In the first, we show that if the potential is constrained to lie between two values, the largest bandgap is o ..."
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is obtained by a mixture of the highest and lowest potential- an exact result valid in any dimension. The second example fixes the first and second moments of the potential and seeks to extremize the bandgap. An exact result is obtained. Finally, we indicate how our techniques may be applied to photonic
Exact results on spin glass models
, 2002
"... Exact and/or rigorous results are reviewed for the Ising and XY /Villain spin glasses in finite dimensions, such as the exact energy, correlation identities and a functional relation between the distribution functions of ferromagnetic and spin glass order parameters. This last relation is useful to ..."
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Exact and/or rigorous results are reviewed for the Ising and XY /Villain spin glasses in finite dimensions, such as the exact energy, correlation identities and a functional relation between the distribution functions of ferromagnetic and spin glass order parameters. This last relation is useful
Some exact results on tachyon condensation in string field theory
- JHEP
"... The study of open string tachyon condensation in string field theory can be drastically simplified by making an appropriate choice of coordinates on the space of string fields. We show that a very natural coordinate system is suggested by the connection between the worldsheet renormalization group a ..."
Abstract
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Cited by 186 (8 self)
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and compute exactly the profiles and tensions of lower dimensional D-branes. September
One-Instanton Tests of the Exact Results in
, 1997
"... We use the microscopic instanton calculus to determine the one-instanton contribution to the quantum modulus u3 = 〈Tr(φ 3) 〉 in N = 2 SU(Nc) supersymmetric QCD with Nf < 2Nc fundamental flavors. This is compared with the corresponding prediction of the hyperelliptic curves which are expected to g ..."
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Cited by 2 (0 self)
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to give exact solutions in this theory. The results agree up to certain regular terms which appear when Nf ≥ 2Nc − 3. The curve prediction for these terms depends upon the curve parameterization which is generically ambiguous when Nf ≥ Nc. In SU(3) theory our instanton calculation of the regular terms
Robust Uncertainty Principles: Exact Signal Reconstruction From Highly Incomplete Frequency Information
, 2006
"... This paper considers the model problem of reconstructing an object from incomplete frequency samples. Consider a discrete-time signal and a randomly chosen set of frequencies. Is it possible to reconstruct from the partial knowledge of its Fourier coefficients on the set? A typical result of this pa ..."
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Cited by 2632 (50 self)
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This paper considers the model problem of reconstructing an object from incomplete frequency samples. Consider a discrete-time signal and a randomly chosen set of frequencies. Is it possible to reconstruct from the partial knowledge of its Fourier coefficients on the set? A typical result
Greed is Good: Algorithmic Results for Sparse Approximation
, 2004
"... This article presents new results on using a greedy algorithm, orthogonal matching pursuit (OMP), to solve the sparse approximation problem over redundant dictionaries. It provides a sufficient condition under which both OMP and Donoho’s basis pursuit (BP) paradigm can recover the optimal representa ..."
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Cited by 916 (9 self)
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This article presents new results on using a greedy algorithm, orthogonal matching pursuit (OMP), to solve the sparse approximation problem over redundant dictionaries. It provides a sufficient condition under which both OMP and Donoho’s basis pursuit (BP) paradigm can recover the optimal
Exact Results on Sinai’s Diffusion
, 1998
"... Abstract: We study the continuum version of Sinai’s problem of a random walker in a random force field in one dimension. A method of stochastic representations is used to represent various probability distributions in this problem (mean probability density function and first passage time distributio ..."
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Cited by 2 (0 self)
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distributions). This method reproduces already known rigorous results and also confirms directly some recent results derived using approximation schemes. We demonstrate clearly, in the Sinai scaling regime, that the disorder dominates the problem and that the thermal distributions tend to zero-one laws.
Exact results via random walks
, 1999
"... Abstract. We study random XY and (dimerized) XX spin-1/2 quantum spin chains at their quantum phase transition driven by the anisotropy and dimerization, respectively. Using exact expressions for magnetization, correlation functions and energy gap, obtained by the free fermion technique, the critica ..."
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Abstract. We study random XY and (dimerized) XX spin-1/2 quantum spin chains at their quantum phase transition driven by the anisotropy and dimerization, respectively. Using exact expressions for magnetization, correlation functions and energy gap, obtained by the free fermion technique
Results 11 - 20
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34,476
