In this work, the concept of mutually unbiased frames is introduced as most general notion unbiasedness for sets composed by linearly independent and normalized vectors. It encompasses already existing notions orthonormal bases, regular simplices, equiangular tight frames, positive operator valued measure, also includes symmetric informationally complete quantum measurements. After introducing ...

The concept of \institution" GB84, GB92] has been proven to be appropriate to describe and classify a wide range of speciication formalisms or logical systems respectively. But considering the relations between logical systems we are faced with many diierent kinds of relevant examples leading to an innation of deenitions of maps between institutions Cer93, CM93, KM93, Mes89, SS92]. The present ...

We investigate frame theory over the binary field Z2, following work of Bodmann, Le, Reza, Tobi and Tomforde. We consider general finite dimensional vector spaces V over Z2 equipped with an (indefinite) inner product (·, ·)V which can be an arbitrary bilinear functional. We characterize precisely when two such spaces (V, (·, ·)V ) and (W, (·, ·)W ) are unitarily equivalent in the sense that the...

Great strides have been made in the use of computer tools to create, edit, filter, and present information, particularly since the tremendous growth in the mainstream popularity of the World Wide Web. The presence of a computationally rich environment at all stages of news distribution provides a unique opportunity to use these tools to improve the reader experience. Information provided for a ...

Tight frames can be characterized as those frames which possess optimal numerical stability properties. In this paper, we consider the question of modifying a general frame to generate a tight frame by rescaling its frame vectors; a process which can also be regarded as perfect preconditioning of a frame by a diagonal operator. A frame is called scalable, if such a diagonal operator exists. We ...