Preface |
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xi | |
Part I Preliminaries, examples and motivations |
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1.1 Preliminaries and notation |
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1.4 Convergence to equilibrium |
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1.5 Reversible Markov chains |
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1.9 Basic probabilistic inequalities |
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1.10 Lurnpable Markov chains |
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2 Two basic examples on abelian groups |
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2.1 Harmonic analysis on finite cyclic groups |
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2.2 Time to reach stationarity for the simple random walk on the discrete circle |
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2.3 Harmonic analysis on the hypercube |
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2.4 Time to reach stationarity in the Ehrenfest diffusion model |
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2.5 The cutoff phenomenon |
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2.6 Radial harmonic analysis on the circle and the hypercube |
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Part II Representation theory and Gelfand pairs |
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3 Basic representation theory of finite groups |
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3.2 Representations, irreducibility and equivalence |
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3.3 Unitary representations |
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3.5 Intertwiners and Schur's lemma |
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3.6 Matrix coefficients and their orthogonality relations |
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3.9 Convolution and the Fourier transform |
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3.10 Fourier analysis of random walks on finite groups |
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3.11 Permutation characters and Burnside's lemma |
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3.12 An application: the enumeration of finite graphs |
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3.14 Examples and applications to the symmetric group |
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4.1 The algebra of bi-K-invariant functions |
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4.2 Intertwining operators for permutation representations |
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4.3 Finite Gelfand pairs: definition and examples |
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4.4 A characterization of Gelfand pairs |
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4.6 The canonical decomposition of L(X) via spherical functions |
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4.7 The spherical Fourier transform |
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4.9 Fourier analysis of an invariant random walk on X |
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5 Distance regular graphs and the Hamming scheme |
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5.1 Harmonic analysis on distance-regular graphs |
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5.4 The group-theoretical approach to the Hammming scheme |
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6 The Johnson scheme and the Bernoulli–Laplace diffusion model |
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6.2 The Gelfand pair (Sn, Sn-m x Sm) and the associated intertwining functions |
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6.3 Time to reach stationarity for the Bernoulli Laplace diffusion model |
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6.4 Statistical applications |
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6.5 The use of Radon transforms |
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7.2 The group Aut(Tq,n) of automorphisms |
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7.3 The ultrametric space |
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7.4 The decomposition of the space L(Σto the nth) and the spherical functions |
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7.5 Recurrence in finite graphs |
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7.6 A Markov chain on Σto the nth |
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Part III Advanced theory |
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8 Posets and the q-analogs |
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8.1 Generalities on posets |
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8.2 Spherical posets and regular semi-lattices |
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8.3 Spherical representations and spherical functions |
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8.4 Spherical functions via Moebius inversion |
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8.5 q-binomial coefficients and the subspaces of a finite vector space |
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8.7 A q-analog of the Hamming scheme |
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8.8 The nonbinary Johnson scheme |
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9 Complements of representation theory |
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9.2 Representations of abelian groups and Pontrjagin duality |
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9.4 Permutation representations |
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9.5 The group algebra revisited |
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9.6 An example of a not weakly symmetric Gelfand pair |
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9.7 Real complex and quaternionic representations: the theorem of Frobenius and Schur |
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9.9 Fourier transform of a measure |
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10 Basic representation theory of the symmetric group |
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10.1 Preliminaries on the symmetric group |
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10.2 Partitions arid Young diagrams |
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10.3 Young tableaux and the Specht modules |
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10.4 Representations corresponding to transposed tableaux |
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10.6 Computation of a Fourier transform on the symmetric group |
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10.7 Random transpositions |
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10.9 James' intersection kernels theorem |
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11 The Gelfand pair (S2n, S2 Sn) and random matchings |
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11.1 The Gelfand pair (S2n, S2 Sn) |
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11.2 The decomposition of L(X) into irreducible components |
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11.3 Computing the spherical functions |
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11.4 The first nontrivial value of a spherical function |
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11.5 The first nontrivial spherical function |
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11.6 Phylogenetic trees and matchings |
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Appendix 1 The discrete trigonometric transforms |
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Appendix 2 Solutions of the exercises |
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Bibliography |
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Index |
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