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X-WR-TIMEZONE:America/Chicago
PRODID:-//University of Iowa//Events 1.0//EN
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BEGIN:VEVENT
DTSTAMP:20241111T131207Z
DTSTART:20241015T133000
DTEND:20241015T143000
SUMMARY:Operator Theory Seminar - Professor Raúl Curto\; Department of Mathematics\, University of Iowa
DESCRIPTION:Semihyponormality of Commuting Pairs of Hilbert Space Operators (continued)\n\nProfessor Raúl Curto\; Department of Mathematics\, University of Iowa\n\nWe will first describe an explicit formula for the square root of positive 2 x 2 operator matrices with commuting entries\, and then use it to define and study semi-hyponormality for commuting pairs of Hilbert space operators. For the well-known 3-parameter family W_(α\, β) (a\, x\, y) of 2-variable weighted shifts\, we have been able to completely identify the parametric regions in the open unit cube where W_(α\, β) (a\, x\, y) is subnormal\, hyponormal\, semi- hyponormal\, and weakly hyponormal. As a result\, we describe in detail concrete sub-regions where\, for instance\, weak hyponormality holds but semi- hyponormality does not hold. To accomplish this\, we employ a new technique emanating from the homogeneous orthogonal decomposition of l²(Z²+). The talk is based on joint work with Jasang Yoon (The University of Texas Rio Grande Valley).We will first describe an explicit formula for the square root of positive 2 x 2 operator matrices with commuting entries\, and then use it to define and study semi-hyponormality for commuting pairs of Hilbert space operators. For the well-known 3-parameter family W_(α\, β) (a\, x\, y) of 2-variable weighted shifts\, we have been able to completely identify the parametric regions in the open unit cube where W_(α\, β) (a\, x\, y) is subnormal\, hyponormal\, semi- hyponormal\, and weakly hyponormal. As a result\, we describe in detail concrete sub-regions where\, for instance\, weak hyponormality holds but semi- hyponormality does not hold. To accomplish this\, we employ a new technique emanating from the homogeneous orthogonal decomposition of l²(Z²+). The talk is based on joint work with Jasang Yoon (The University of Texas Rio Grande Valley).\n\nThose who wish to participate remotely may do so via Zoom at https://uiowa.zoom.us/j/95316149275\n\n\nhttps://events.uiowa.edu/88160
LOCATION:Van Allen Hall\, 309\, 30 North Dubuque Street\, Iowa City\, IA 52242
UID:edu.uiowa.events-prod-88160
X-ALT-DESC;FMTTYPE=text/html:#### Semihyponormality of Commuting Pairs of Hilbert Space Operators (continued)

\n\n**Professor Raúl Curto\; Department of Mathematics\, University of Iowa**

\n\nWe will first describe an explicit formula for the square root of positive 2 x 2 operator matrices with commuting entries\, and then use it to define and study semi-hyponormality for commuting pairs of Hilbert space operators. For the well-known 3-parameter family W_(α\, β) (a\, x\, y) of 2-variable weighted shifts\, we have been able to completely identify the parametric regions in the open unit cube where W_(α\, β) (a\, x\, y) is subnormal\, hyponormal\, semi- hyponormal\, and weakly hyponormal. As a result\, we describe in detail concrete sub-regions where\, for instance\, weak hyponormality holds but semi- hyponormality does not hold. To accomplish this\, we employ a new technique emanating from the homogeneous orthogonal decomposition of l²(Z²+). The talk is based on joint work with Jasang Yoon (The University of Texas Rio Grande Valley).We will first describe an explicit formula for the square root of positive 2 x 2 operator matrices with commuting entries\, and then use it to define and study semi-hyponormality for commuting pairs of Hilbert space operators. For the well-known 3-parameter family W_(α\, β) (a\, x\, y) of 2-variable weighted shifts\, we have been able to completely identify the parametric regions in the open unit cube where W_(α\, β) (a\, x\, y) is subnormal\, hyponormal\, semi- hyponormal\, and weakly hyponormal. As a result\, we describe in detail concrete sub-regions where\, for instance\, weak hyponormality holds but semi- hyponormality does not hold. To accomplish this\, we employ a new technique emanating from the homogeneous orthogonal decomposition of l²(Z²+). The talk is based on joint work with Jasang Yoon (The University of Texas Rio Grande Valley).

\n\nThose who wish to participate remotely may do so via Zoom at https://uiowa.zoom.us/j/95316149275

\n

https://events.uiowa.edu/88160
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