Zobrazeno 1 - 10
of 107
pro vyhledávání: '"Kristian Seip"'
Autor:
Ole Fredrik Brevig, Kristian Seip
A Hankel operator $\mathbf{H}_\varphi$ on the Hardy space $H^2$ of the unit circle with analytic symbol $\varphi$ has minimal norm if $\|\mathbf{H}_\varphi\|=\|\varphi \|_2$ and maximal norm if $\|\mathbf{H}_\varphi\| = \|\varphi\|_\infty$. The Hanke
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::278406e6fb7666b1ca256dad1e033855
http://arxiv.org/abs/2301.07937
http://arxiv.org/abs/2301.07937
Publikováno v:
Geometric and Functional Analysis
Dipòsit Digital de la UB
Universidad de Barcelona
Dipòsit Digital de la UB
Universidad de Barcelona
We describe the idempotent Fourier multipliers that act contractively on $H^p$ spaces of the $d$-dimensional torus $\mathbb{T}^d$ for $d\geq 1$ and $1\leq p \leq \infty$. When $p$ is not an even integer, such multipliers are just restrictions of cont
Publikováno v:
Oberwolfach Reports. 14:3035-3069
Publikováno v:
Journal of Mathematical Analysis and Applications
Dipòsit Digital de la UB
Universidad de Barcelona
Dipòsit Digital de la UB
Universidad de Barcelona
A sharp version of a recent inequality of Kovalev and Yang on the ratio of the $(H^1)^\ast$ and $H^4$ norms for certain polynomials is obtained. The inequality is applied to establish a sharp and tractable sufficient condition for the Wirtinger deriv
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::8de32983e46cb107323172f4547e9696
https://hdl.handle.net/11250/2722488
https://hdl.handle.net/11250/2722488
Publikováno v:
Studia Mathematica
We prove that the norm of the Riesz projection from $L^\infty(\Bbb{T}^n)$ to $L^p(\Bbb{T}^n)$ is $1$ for all $n\ge 1$ only if $p\le 2$, thus solving a problem posed by Marzo and Seip in 2011. This shows that $H^p(\Bbb{T}^{\infty})$ does not contain t
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::854c642db5f8702393aff840f5ef0f03
http://arxiv.org/abs/2005.11951
http://arxiv.org/abs/2005.11951
Autor:
Kristian Seip
Publikováno v:
Journal d'Analyse Mathematique
This paper studies zeta functions of the form $\sum_{n=1}^{\infty} \chi(n) n^{-s}$, with $\chi$ a completely multiplicative function taking only unimodular values. We denote by $\sigma(\chi)$ the infimum of those $\alpha$ such that the Dirichlet seri
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::2931749ac68b00cfdab3f4a17f202e7f
https://hdl.handle.net/11250/2687985
https://hdl.handle.net/11250/2687985
Autor:
Kristian Seip, Eric Saias
Publikováno v:
Funct. Approx. Comment. Math. 63, no. 1 (2020), 125-131
We study multiplicative functions $f$ satisfying $|f(n)|\le 1$ for all $n$, the associated Dirichlet series $F(s):=\sum_{n=1}^{\infty} f(n) n^{-s}$, and the summatory function $S_f(x):=\sum_{n\le x} f(n)$. Up to a possible trivial contribution from t
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::7eabe6c67b10d1fd8dd420eee0a09ec8
http://arxiv.org/abs/1911.05365
http://arxiv.org/abs/1911.05365
Publikováno v:
Bulletin of the London Mathematical Society. 50:709-724
The $2$kth pseudomoments of the Riemann zeta function $\zeta(s)$ are, following Conrey and Gamburd, the $2k$th integral moments of the partial sums of $\zeta(s)$ on the critical line. For fixed $k>1/2$, these moments are known to grow like $(\log N)^
Publikováno v:
Hardy-Ramanujan Journal
Hardy-Ramanujan Journal, Hardy-Ramanujan Society, 2019, 41, pp.85-97
Hardy-Ramanujan Journal, Hardy-Ramanujan Society, 2019, 41, pp.85-97
Let $\gamma$ denote the imaginary parts of complex zeros $\rho = \beta+i\gamma$ of $\zeta(s)$. The problem of analytic continuation of the function $G(s) := \sum\limits_{\gamma > 0}\gamma^{-s}$ to the left of the line $\Re s = -1$ is investigated, an
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::bc1ce4527b26714c7d9fa699c8e67144
https://hal.archives-ouvertes.fr/hal-01986703/document
https://hal.archives-ouvertes.fr/hal-01986703/document
Publikováno v:
Transactions of the American Mathematical Society
We study $H^p$ spaces of Dirichlet series, called $\mathcal{H}^p$, for the range $0
Comment: This paper has been accepted for publication in Transactions of the AMS. arXiv admin note: substantial text overlap with arXiv:1701.06842
Comment: This paper has been accepted for publication in Transactions of the AMS. arXiv admin note: substantial text overlap with arXiv:1701.06842
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::227568838dfb88e0380bb565ca83990e
https://hdl.handle.net/11250/2609726
https://hdl.handle.net/11250/2609726