Spectrum and essential spectrum of linear combinations of composition operators on the Hardy space H2

Document Type: research paper

Authors

1 Professor, Department of Mathematics, Shiraz University of Technology, Shiraz, Iran.

2 Professor, Department of Mathematics, Shiraz Branch, Islamic Azad University, Shiraz, Iran.

3 Ph.D. Student, Department of Mathematics, Shiraz University of Technology, Shiraz, Iran.

Abstract

Let -----. For an analytic self-map ---  of --- , Let --- be the composition operator with composite map ---  so that ----. Let ---  be a bounded analytic function on --- . The weighted composition operator ---  is defined by --- . Suppose that ---  is the Hardy space, consisting of all analytic functions defined on --- , whose Maclaurin cofficients are square summable. .....

Keywords


Article Title [Persian]

طیف و طیف اساسی ترکیبات خطی عملگرهای ترکیبی روی فضای هاردی H2

Authors [Persian]

  • محمود حاجی شعبانی 1
  • مهسا فاتحی 2
  • ملیحه فرضی 3
1 استاد، دانشکده ریاضی، دانشگاه صنعتی شیراز، شیراز، ایران
2 استاد، گروه ریاضی، واحد شیراز، دانشگاه آزاد اسلامی، شیراز، ایران
3 دانشجوی دکتری، دانشکده ریاضی، دانشگاه صنعتی شیراز، شیراز، ایران
Abstract [Persian]

فرض کنید ---. اگر---  یک خود نگاشت تحلیلی از --- باشد، برای هر  --- تحلیلی روی ---، عملگر ترکیبی  --- را به صورت  --- تعریف کرده و  --- را تابع ترکیب می‌نامیم. 

Keywords [Persian]

  • فضای هاردی
  • عملگر ترکیبی
  • طیف
  • طیف اساسی

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