Imagine a phone directory containing N names arranged in completely random order. In order to find someone's phone number with a probability of , any classical algorithm (whether deterministic or probabilistic) will need to look at a minimum of names. Quantum mechanical systems can be in a

Summary.-The term apoptosis is proposed for a hitherto little recognized mechanism of controlled cell deletion, which appears to play a complementary but opposite role to mitosis in the regulation of animal cell populations. Its morphological features suggest that it is an active, inherently

be implemented and introduce some new, purely quantum mechanical primitives, such as changing the computational basis and carrying out an arbitrary unitary transformation of polynomially bounded dimension. We also consider the precision to which the transition amplitudes of a quantum Turing machine need

A computer is generally considered to be a universal computational device; i.e., it is believed able to simulate any physical computational device with a cost in com-putation time of at most a polynomial factol: It is not clear whether this is still true when quantum mechanics is taken

A digital computer is generally believed to be an efficient universal computing device; that is, it is believed able to simulate any physical computing device with an increase in computation time by at most a polynomial factor. This may not be true when quantum mechanics is taken into consideration

Humans appear to be able to learn new concepts without needing to be programmed explicitly in any conventional sense. In this paper we regard learning as the phenomenon of knowledge acquisition in the absence of explicit programming. We give a precise methodology for studying this phenomenon from

“Somebody says, ‘You know, you people always say that space is continuous. How do you know when you get to a small enough dimension that there really are enough points in between, that it isn’t just a lot of dots separated by little distances? ’ Or they say, ‘You know those quantum mechanical

In my lecture I consider integrals over moduli spaces of supersymmetric gauge field configurations (instantons, Higgs bundles, torsion free sheaves). The applications are twofold: physical and mathematical; they involve supersymmetric quantum mechanics of D-particles in various dimensions, direct

The phenomenon of growth, decline and death-aging-has been the source of consider-able speculation (1, 8, 10). This cycle seems to be a more or less direct function of the meta-bolic rate and this in turn depends on the species (animal or plant) on which are super-imposed the factors of heredity

Traditional views of automaticity are in need of revision. For example, automaticity otten has been treated as an all-or-none phenomenon, and traditional ~es have held that automatic processes are independent of attention. Yet recent empirical data suggest that automatic processes are continu-ous