By the new spectrum originated from the single-valued extension property,we give the necessary and sufficient conditions for a bounded linear operator defined on a Banach space for which property(ω)holds.Meanwhile,th...By the new spectrum originated from the single-valued extension property,we give the necessary and sufficient conditions for a bounded linear operator defined on a Banach space for which property(ω)holds.Meanwhile,the relationship between hypercyclic property(or supercyclic property)and property(ω)is discussed.展开更多
For a bounded operator T acting on an infinite dimensional separable Hilbert space H, we prove the following assertions： （i） If T or T＊ ∈ SC, then generalized a- Browder＇s theorem holds for f（T） for every f ∈...For a bounded operator T acting on an infinite dimensional separable Hilbert space H, we prove the following assertions： （i） If T or T＊ ∈ SC, then generalized a- Browder＇s theorem holds for f（T） for every f ∈ Hol（σ（T））. （ii） If T or T＊ ∈ HC has topological uniform descent at all λ ∈ iso（a（T））, then generalized Weyl＇s theorem holds for f（T） for every f ∈ Hol（σ（T））. （iii） If T ∈ HC has topological uniform descent at all λ ∈（T）, then T satisfies generalized Weyl＇s theorem. （iv） Let T ∈ HC. If T satisfies the growth condition Gd（d 〉 1）, then generalized Weyl＇s theorem holds for f（T） for every f ∈ Hol（σ（T））. （v） If T ∈ SC, then, f（OssF＋ （T）） = aSBF＋ （f（T）） for all f ∈ Hol（σ（T））. （vi） Let T be a-isoloid such that T＊ ∈ HC. If T - AI has finite ascent at every A ∈ Eσ（T） and if F is of finite rank on Hsuch that TF = FT, then T ∈ F obeys generalized a-Weyl＇s theorem.展开更多
We denote N, R, C the sets of natural, real and complex numbers respectively. Let (λ<sub>n</sub>), n ∈ N be an unbounded sequence of complex numbers. Costakis has proved the following result. There ...We denote N, R, C the sets of natural, real and complex numbers respectively. Let (λ<sub>n</sub>), n ∈ N be an unbounded sequence of complex numbers. Costakis has proved the following result. There exists an entire function f with the following property: for every x, y ∈ R with 0 , every θ ∈(0,1) and every a ∈ C there is a subsequence of natural numbers (m<sub>n</sub>), n ∈ N such that, for every compact subset L ⊆C , In the present paper we show that the constant function a cannot be replaced by any non-constant entire function G. This is so even if one demands the convergence in (*) only for a single radius r and a single positive number θ. This result is related with the problem of existence of common universal vectors for an uncountable family of sequences of translation operators.展开更多
In this paper. we stady the nonwandering operator, which is a linear operator with chaos character and is in intnite dimensionol linear space. We give the hypercyclic bacomposition on the compact set of nonwandering o...In this paper. we stady the nonwandering operator, which is a linear operator with chaos character and is in intnite dimensionol linear space. We give the hypercyclic bacomposition on the compact set of nonwandering operators.展开更多
Modifying the method of Ansari, we give some criteria for hypercyclicity of quasi-Mazur spaces. They can be applied to judging hypercyclicity of non-complete and non-metrizable locally convex spaces. For some special ...Modifying the method of Ansari, we give some criteria for hypercyclicity of quasi-Mazur spaces. They can be applied to judging hypercyclicity of non-complete and non-metrizable locally convex spaces. For some special locally convex spaces, for example, KSthe （LF）-sequence spaces and countable inductive limits of quasi-Mazur spaces, we investigate their hypercyclicity. As we see, bounded biorthogonal systems play an important role in the construction of Ansari. Moreover, we obtain characteristic conditions respectively for locally convex spaces having bounded sequences with dense linear spans and for locally convex spaces having bounded absorbing sets, which are useful in judging the existence of bounded biorthogonal systems.展开更多
基金Supported by the National Natural Science Foundation of China(Grant No.111501419)the Doctoral Fund of Shaanxi province of China(Grant No.2017BSHEDZZ108)the Natural Science Basic Research Plan in Shaanxi Province of China(Grant No.2021JM-519)。
文摘By the new spectrum originated from the single-valued extension property,we give the necessary and sufficient conditions for a bounded linear operator defined on a Banach space for which property(ω)holds.Meanwhile,the relationship between hypercyclic property(or supercyclic property)and property(ω)is discussed.
文摘For a bounded operator T acting on an infinite dimensional separable Hilbert space H, we prove the following assertions： （i） If T or T＊ ∈ SC, then generalized a- Browder＇s theorem holds for f（T） for every f ∈ Hol（σ（T））. （ii） If T or T＊ ∈ HC has topological uniform descent at all λ ∈ iso（a（T））, then generalized Weyl＇s theorem holds for f（T） for every f ∈ Hol（σ（T））. （iii） If T ∈ HC has topological uniform descent at all λ ∈（T）, then T satisfies generalized Weyl＇s theorem. （iv） Let T ∈ HC. If T satisfies the growth condition Gd（d 〉 1）, then generalized Weyl＇s theorem holds for f（T） for every f ∈ Hol（σ（T））. （v） If T ∈ SC, then, f（OssF＋ （T）） = aSBF＋ （f（T）） for all f ∈ Hol（σ（T））. （vi） Let T be a-isoloid such that T＊ ∈ HC. If T - AI has finite ascent at every A ∈ Eσ（T） and if F is of finite rank on Hsuch that TF = FT, then T ∈ F obeys generalized a-Weyl＇s theorem.
文摘We denote N, R, C the sets of natural, real and complex numbers respectively. Let (λ<sub>n</sub>), n ∈ N be an unbounded sequence of complex numbers. Costakis has proved the following result. There exists an entire function f with the following property: for every x, y ∈ R with 0 , every θ ∈(0,1) and every a ∈ C there is a subsequence of natural numbers (m<sub>n</sub>), n ∈ N such that, for every compact subset L ⊆C , In the present paper we show that the constant function a cannot be replaced by any non-constant entire function G. This is so even if one demands the convergence in (*) only for a single radius r and a single positive number θ. This result is related with the problem of existence of common universal vectors for an uncountable family of sequences of translation operators.
文摘In this paper. we stady the nonwandering operator, which is a linear operator with chaos character and is in intnite dimensionol linear space. We give the hypercyclic bacomposition on the compact set of nonwandering operators.
基金Supported by the National Natural Science Foundation of China(10571035,10871141)
文摘Modifying the method of Ansari, we give some criteria for hypercyclicity of quasi-Mazur spaces. They can be applied to judging hypercyclicity of non-complete and non-metrizable locally convex spaces. For some special locally convex spaces, for example, KSthe （LF）-sequence spaces and countable inductive limits of quasi-Mazur spaces, we investigate their hypercyclicity. As we see, bounded biorthogonal systems play an important role in the construction of Ansari. Moreover, we obtain characteristic conditions respectively for locally convex spaces having bounded sequences with dense linear spans and for locally convex spaces having bounded absorbing sets, which are useful in judging the existence of bounded biorthogonal systems.
基金supported in part by the Foundation of Henan Educational Committee(18A110023)the Scientific Research Foundation for Ph.D.of Henan Normal University(No.qd16151)
文摘This paper characterizes some sufficient and necessary conditions for the hypercyclicity of multiples of composition operators on Hlog,0∞.
