设A是作用在复Hilbert空间H上的有界线性算子,证明了A的Duggal变换的数值域包含于A的数值域;同时,利用简洁的方法证明了A的Aluthge变换的数值域等于A的*-Aluthge变换的数值域.
Let A be a bounded linear operator on a complex Hilbert space H.It was proved that the numericalrange of the Duggal transform of A was contained in that of A. It was also proved that the numerical range of the Aluthge transform of A was equal to that of the * -Aluthge transform of A by a simplified method.