## Weighted Littlewood-Paley Theory and Exponential-Square IntegrabilitySpringer, 31 dec. 2007 - 227 pagini Littlewood-Paley theory is an essential tool of Fourier analysis, with applications and connections to PDEs, signal processing, and probability. It extends some of the benefits of orthogonality to situations where orthogonality doesn’t really make sense. It does so by letting us control certain oscillatory infinite series of functions in terms of infinite series of non-negative functions. Beginning in the 1980s, it was discovered that this control could be made much sharper than was previously suspected. The present book tries to give a gentle, well-motivated introduction to those discoveries, the methods behind them, their consequences, and some of their applications. |

### Din interiorul cărții

Rezultatele 1 - 5 din 86

...

**f**(x)|4dx ) 1/4. To make things specific,

**let's**suppose that our functions are defined on [0,1). The collection {exp(2πinx)}∞−∞ defines a complete orthonormal family in L2[0,1). Now, if

**f**∈ L4[0,1), then the coefficients λn ≡ ∫ 1 0

**f**...

Michael Wilson. where

**f**∗ g is the usual convolution,

**f**∗g(x)= ∫ Rd

**f**(x−y)g(y)dy= ∫ Rd

**f**(y)g(x−y)dy defined for ...

**let**l(I) denote I's length (which is the same as |I|). A cube Q ⊂ Rd is a cartesian product of d intervals all ...

...

**Let**X be a positive number, and

**let**FA be the family of dyadic cubes Q such that 1 - d X. :// QC = Our hypothesis on

**f**implies that every Q € JFX is contained in some maximal Q'e F.A. (This, by the way, holds even if FA is empty: check ...

... f|dx≤ | ̃Q||Q|λ, from which the inequality follows. Notice that, by the Lebesgue differentiation theorem, |f ...

**Let f**satisfy 1.4. For every λ > 0, there is a (possibly empty) family F of pairwise disjoint dyadic cubes such that f = g ...

...

**Let's**get back to 2.2. We begin by rewriting it in a funny way. Notice that 1 = 1|I| ∫ χI(x)dx. Therefore, ∑I|λI(

**f**)|2=∑I|λI(

**f**)|21|I| ∫ χI(x)dx = ∫ ( ∑I |λI(

**f**)| 2 |I| χI(x) ) dx. The one-dimensional dyadic square function, which ...

### Cuprins

1 | |

9 | |

Exponential Square 39 | 38 |

Many Dimensions Smoothing | 69 |

The Calderón Reproducing Formula I | 85 |

The Calderón Reproducing Formula II | 101 |

The Calderón Reproducing Formula III | 129 |

Schrödinger Operators 145 | 144 |

Orlicz Spaces | 161 |

Goodbye to Goodλ | 189 |

A Fourier Multiplier Theorem | 197 |

VectorValued Inequalities | 203 |

Random Pointwise Errors | 213 |

References | 219 |

Index 223 | 222 |

Some Singular Integrals | 151 |

### Alte ediții - Afișează-le pe toate

Weighted Littlewood-Paley Theory and Exponential-Square ..., Ediția 1924 Michael Wilson Previzualizare limitată - 2008 |