In this paper we consider the implications of a cosmological constant for the evolution of the universe, under a set of assumptions motivated by the holographic and horizon complementarity principles. We discuss the “causal patch” description of spacetime required by this framework, and present some simple examples of cosmologies described this way. We argue that these assumptions inevitably le...

A YOUNG MAN TROUBLED BY DISTURBING DREAMS is led out of the village by an old man, who carries a rattle, a drum, and a blanket. They walk for two days and climb to the top of the “spirit” mountain. After spending a night drumming and chanting over the youth, the old man prepares to leave, taking with him all food and water. As he departs, he tells the youth, “When the spirits come for you, you ...

Bortolotti’s Delusions and Other Irrational Beliefs defends the view that delusions are beliefs on a continuum with other beliefs. A different view is that delusions are more like illusions, that is, they arise from faulty perception. This view, which is not targeted by the book, makes it easier to explain why delusions are so alien and disabling but needs to appeal to forensic aspects of funct...

Mitotic spindles maintain a roughly constant length in metaphase, so the forces between the spindle poles are balanced. A new study involving screening molecules believed to mediate this force balance has found that spindle length is relatively insensitive to perturbations of molecular motor force-generating activities, but more sensitive to perturbation of microtubule assembly regulators and c...

We propose two experimental schemes for quantum state discrimination that achieve the optimal tradeoff between the probability of correct identification and the disturbance on the quantum state.

Consider a situation in which a quantum system is secretly prepared in a state chosen from the known set of n states. We show that the fundamental properties of classical and quantum signals lead to a principle that gives a definite distinction between the operations that preserve the states of the system and those that do not. Many types of no-cloning and no-imprinting conditions can easily be...

BACKGROUND Despite long-term declines in US stroke mortality rates, declines have slowed in the past decade and targets for blacks for the years 2000 and 2010 seem attainable only by extraordinary measures, if at all. This review focuses attention on key aspects of this problem. Data from the US National Center for Health Statistics and reports of population-based studies of stroke mortality pu...

Different types of pain are often present in the same individual with spinal cord injury (SCI). Relieving the most disturbing of these pains may substantially affect quality of life. Persons with SCI and chronic pain (n = 194) completed a structured interview that detailed the characteristics of each pain they experienced. Pairwise analyses revealed that the following characteristics were more ...