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1 | (16) |
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1.1 Two Extension Problems |
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3 | (2) |
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3 | (2) |
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5 | (1) |
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6 | (5) |
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6 | (4) |
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1.3.2 An Application of Lemma 1.1: A Positive Definite Function on an Infinite Dimensional Vector Space |
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10 | (1) |
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1.4 Overview of Applications of RKHSs |
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11 | (3) |
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1.4.1 Connections to Gaussian Processes |
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11 | (3) |
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14 | (1) |
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15 | (2) |
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2 Extensions of Continuous Positive Definite Functions |
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17 | (30) |
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18 | (5) |
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21 | (2) |
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2.2 The Skew-Hermitian Operator D(F) HF |
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23 | (11) |
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2.2.1 The Case of Conjugations |
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26 | (5) |
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2.2.2 Illustration: G = R, Correspondence Between the Two Extension Problems |
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31 | (3) |
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2.3 Enlarging the Hilbert Space |
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34 | (4) |
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38 | (5) |
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40 | (1) |
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2.4.2 Comparison of p.d. Kernels |
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40 | (3) |
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2.5 Spectral Theory of D(F) and Its Extensions |
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43 | (4) |
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3 The Case of More General Groups |
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47 | (20) |
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3.1 Locally Compact Abelian Groups |
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47 | (7) |
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54 | (13) |
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3.2.1 The GNS Construction |
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59 | (2) |
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3.2.2 Local Representations |
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61 | (2) |
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3.2.3 The Convex Operation in Ext (F) |
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63 | (4) |
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67 | (26) |
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67 | (5) |
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72 | (3) |
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75 | (2) |
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4.4 Example: e--|x| in (--a, a), Extensions to T = R/Z |
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77 | (4) |
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4.4.1 General Consideration |
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78 | (3) |
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4.5 Example: e--|x| in (--a, a), Extensions to R |
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81 | (8) |
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4.6 Example: A Non-extendable p.d. Function in a Neighborhood of Zero in G = R2 |
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89 | (4) |
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4.6.1 A Locally Defined p.d. Functions F on G = R2 with Ext (F) = ø |
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91 | (2) |
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5 Type I vs. Type II Extensions |
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93 | (22) |
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93 | (6) |
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99 | (7) |
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103 | (3) |
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5.3 The Deficiency-Indices of D(F) |
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106 | (4) |
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108 | (2) |
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5.4 The Example 5.3, Green's Function, and an HF-ONB |
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110 | (5) |
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6 Spectral Theory for Mercer Operators, and Implications for Ext (F) |
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115 | (36) |
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6.1 Groups, Boundary Representations, and Renormalization |
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116 | (17) |
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6.2 Shannon Sampling, and Bessel Frames |
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133 | (4) |
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6.3 Application: The Case of F2 and Rank-1 Perturbations |
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137 | (5) |
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6.4 Positive Definite Functions, Green's Functions, and Boundary |
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142 | (9) |
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6.4.1 Connection to the Energy Form Hilbert Spaces |
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147 | (4) |
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151 | (20) |
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7.1 The RKHSs for the Two Examples F2 and F3 in Table 5.1 |
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151 | (18) |
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152 | (3) |
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7.1.2 The Case of F2(x) = 1 -- |x|, x ε (--1/2, 1/2) |
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155 | (6) |
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7.1.3 The Case of F3(x) = e--|x|, x ε (--1, 1) |
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161 | (4) |
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7.1.4 Integral Kernels and Positive Definite Functions |
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165 | (1) |
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7.1.5 The Ornstein-Uhlenbeck Process Revisited |
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166 | (1) |
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7.1.6 An Overview of the Two Cases: F2 and F3 |
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167 | (2) |
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169 | (2) |
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8 Comparing the Different RKHSs F and K |
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171 | (22) |
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177 | (2) |
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8.2 Radially Symmetric Positive Definite Functions |
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179 | (2) |
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8.3 Connecting F and F When F Is a Positive Definite Function |
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181 | (2) |
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8.4 The Imaginary Part of a Positive Definite Function |
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183 | (10) |
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8.4.1 Connections to, and Applications of, Bochner's Theorem |
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187 | (6) |
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193 | (4) |
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10 Models for, and Spectral Representations of, Operator Extensions |
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197 | (20) |
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10.1 Model for Restrictions of Continuous p.d. Functions on R |
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197 | (6) |
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10.2 A Model of ALL Deficiency Index-(1, 1) Operators |
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203 | (6) |
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10.2.1 Momentum Operators in L2 (0, 1) |
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207 | (2) |
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10.2.2 Restriction Operators |
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209 | (1) |
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10.3 The Case of Indices (d, d) Where d > 1 |
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209 | (2) |
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10.4 Spectral Representation of Index (1, 1) Hermitian Operators |
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211 | (6) |
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11 Overview and Open Questions |
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217 | (2) |
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11.1 From Restriction Operator to Restriction of p.d. Function |
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217 | (1) |
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11.2 The Splitting HF = HF(atom) + HF(ac) + HF(sing) |
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217 | (1) |
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218 | (1) |
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11.4 The Extreme Points of Ext (F) and {F} |
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218 | (1) |
References |
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219 | (10) |
Index |
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229 | |