Powered by OpenAIRE graph
Found an issue? Give us feedback
image/svg+xml art designer at PLoS, modified by Wikipedia users Nina, Beao, JakobVoss, and AnonMoos Open Access logo, converted into svg, designed by PLoS. This version with transparent background. http://commons.wikimedia.org/wiki/File:Open_Access_logo_PLoS_white.svg art designer at PLoS, modified by Wikipedia users Nina, Beao, JakobVoss, and AnonMoos http://www.plos.org/ Transactions of the ...arrow_drop_down
image/svg+xml art designer at PLoS, modified by Wikipedia users Nina, Beao, JakobVoss, and AnonMoos Open Access logo, converted into svg, designed by PLoS. This version with transparent background. http://commons.wikimedia.org/wiki/File:Open_Access_logo_PLoS_white.svg art designer at PLoS, modified by Wikipedia users Nina, Beao, JakobVoss, and AnonMoos http://www.plos.org/
image/svg+xml Jakob Voss, based on art designer at PLoS, modified by Wikipedia users Nina and Beao Closed Access logo, derived from PLoS Open Access logo. This version with transparent background. http://commons.wikimedia.org/wiki/File:Closed_Access_logo_transparent.svg Jakob Voss, based on art designer at PLoS, modified by Wikipedia users Nina and Beao
zbMATH Open
Article
Data sources: zbMATH Open
Transactions of the American Mathematical Society
Article . 1977 . Peer-reviewed
Data sources: Crossref
Transactions of the American Mathematical Society
Article . 1977 . Peer-reviewed
Data sources: Crossref
versions View all 3 versions
addClaim

Moduli of Continuity for Exponential Lipschitz Classes

Moduli of continuity for exponential Lipschitz classes
Authors: De Land, Paul;

Moduli of Continuity for Exponential Lipschitz Classes

Abstract

Let Ψ \Psi be a convex function, and let f be a real-valued function on [0, 1]. Let a modulus of continuity associated to Ψ \Psi be given as \[ Q Ψ ( δ , f ) = inf { λ : 1 δ ∬ | x − y | ⩽ δ Ψ ( | f ( x ) − f ( y ) | λ ) d x d y ⩽ Ψ ( 1 ) } . {Q_\Psi }(\delta ,f) = \inf \left \{ {\lambda :\frac {1}{\delta }\iint \limits _{|x - y| \leqslant \delta } {\Psi \left ( {\frac {{|f(x) - f(y)|}}{\lambda }} \right )}\;dx\;dy\; \leqslant \Psi (1)} \right \}. \] It is shown that ∫ 0 1 Q Ψ ( δ , f ) d ( − Ψ − 1 ( c / δ ) ) > ∞ \smallint _0^1{Q_\Psi }(\delta ,f)\;d\;( - {\Psi ^{ - 1}}(c/\delta )) > \infty guarantees the essential continuity of f, and, in fact, a uniform Lipschitz estimate is given. In the case that Ψ ( u ) = exp u 2 \Psi (u) = \exp \;{u^2} the above condition reduces to \[ ∫ 0 1 Q exp u 2 ( δ , f ) d δ δ log ⁡ ( c / δ ) > ∞ . \int _0^1 {{Q_{\exp \;{u^2}}}\;(\delta ,f)\frac {{d\delta }}{{\delta \sqrt {\log (c/\delta )} }}\; > \infty .} \] This exponential square condition is satisfied almost surely by the random Fourier series f t ( x ) = Σ n = 1 ∞ a n R n ( t ) e i n x {f_t}(x) = \Sigma _{n = 1}^\infty {a_n}{R_n}(t){e^{inx}} , where { R n } \{ {R_n}\} is the Rademacher system, as long as \[ ∫ 0 1 a n 2 sin 2 ( n δ / 2 ) d δ δ log ⁡ ( 1 / δ ) > ∞ . \int _0^1 {\sqrt {a_n^2{{\sin }^2}(n\delta /2)} \frac {{d\delta }}{{\delta \sqrt {\log (1/\delta )} }}\; > \infty .} \] Hence, the random essential continuity of f t ( x ) {f_t}(x) is guaranteed by each of the above conditions.

Keywords

Continuity and related questions (modulus of continuity, semicontinuity, discontinuities, etc.) for real functions in one variable, Convexity of real functions in one variable, generalizations, Probabilistic methods for one variable harmonic analysis

  • BIP!
    Impact byBIP!
    selected citations
    These citations are derived from selected sources.
    This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).
    0
    popularity
    This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network.
    Average
    influence
    This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).
    Average
    impulse
    This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network.
    Average
Powered by OpenAIRE graph
Found an issue? Give us feedback
selected citations
These citations are derived from selected sources.
This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).
BIP!Citations provided by BIP!
popularity
This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network.
BIP!Popularity provided by BIP!
influence
This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).
BIP!Influence provided by BIP!
impulse
This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network.
BIP!Impulse provided by BIP!
0
Average
Average
Average
bronze