Generalised supersymmetry and p-brane actions

We investigate the most general N=1 graded extension of the Poincare algebra, and find the corresponding supersymmetry transformations and the associated superspaces. We find that the supersymmetry for which {Q,Q} = P is not special, and in fact must be treated democratically with a whole class of supersymmetries. We show that there are two distinct types of grading, and a new class of general spinors is defined. The associated superspaces are shown to be either of the usual type, or flat with no torsion. p-branes are discussed in these general superspaces and twelve dimensions emerges as maximal. New types of brane are discovered which could explain many features of the standard p-brane theories.Comment: 29 pages, LaTex, no figures. Errors in degrees of freedom counting corrected, leading to altered brane sca

Superconformal Ward Identities and N=2 Yang-Mills Theory

A reformulation of the superconformal Ward identities that combines all the superconformal currents and the associated parameters in one multiplet is given for theories with rigid N=1 or N=2 supersymmetry. This form of the Ward Identities is applied to spontaneously broken N=2 Yang-Mills theory and used to derive a condition on the low energy effective action. This condition is satisfied by the solution proposed by Seiberg and Witten.Comment: 25 pages, plain Te

M 5-brane and superconformal (0,2) tensor multiplet in 6 dimensions

We present a gauge-fixed M 5-brane action: a 6-dimensional field theory of a self-interacting (0,2) tensor multiplet with 32 worldvolume supersymmetries. The quadratic part of this action is shown to be invariant under rigid OSp(6,2|4) superconformal symmetry, with 16 supersymmetries and 16 special supersymmetries. We explore a deep relation between the superconformal symmetry on the worldvolume of the brane and symmetry of the near horizon anti-de Sitter infinite throat geometry of the M 5-brane in space-time.Comment: 42 pages, latex, no figures; v2: some formulas corrected:v3: version to be published in Nuclear Physics B; v4:The name of the conformal algebra OSp(6,2|4) has been replaced by the correct name OSp(8*|4

AdS_3 OM theory and the self-dual string or Membranes ending on the Five-brane

We describe properties of the M-theory five-brane containing $Q$ coincident self-dual strings on its worldvolume. This is the five-brane description of Q membranes ending on the five-brane. In particular, we consider a Maldacena-like low energy limit in the six-dimensional worldvolume which yields a near `horizon' description of the self-dual string using light open membranes, i.e. OM theory, in an AdS_3 x S^3 geometry.Comment: 13 pages, latex, v2: corrected open membrane metric prefactor + typo

The twelve dimensional super (2+2)-brane

We discuss supersymmetry in twelve dimensions and present a covariant supersymmetric action for a brane with worldsheet signature (2,2), called a super (2+2)-brane, propagating in the osp(64,12) superspace. This superspace is explicitly constructed, and is trivial in the sense that the spinorial part is a trivial bundle over spacetime, unlike the twisted superspace of usual Poincare supersymmetry. For consistency, it is necessary to take a projection of the superspace. This is the same as the projection required for worldvolume supersymmetry. Upon compactification of this superspace, a torsion is naturally introduced and we produce the membrane and type IIB string actions in 11 and 10 dimensional Minkowski spacetimes. In addition, the compactification of the twelve dimensional supersymmetry algebra produces the correct algebras for these theories, including central charges. These considerations thus give the type IIB string and M-theory a single twelve dimensional origin.Comment: 32 pages LaTex, no figures, minor comments and address(!) adde

D=3, N=8 conformal supergravity and the Dragon window

We give a superspace description of D=3, N=8 supergravity. The formulation is off-shell in the sense that the equations of motion are not implied by the superspace constraints (but an action principle is not given). The multiplet structure is unconventional, which we connect to the existence of a "Dragon window", that is modules occurring in the supercurvature but not in the supertorsion. According to Dragon's theorem this cannot happen above three dimensions. We clarify the relevance of this window for going on the conformal shell, and discuss some aspects of coupling to conformal matter.Comment: plain tex, 24 pp v2: minor change

The positive ramifications of false memories using a perceptual closure task

The negative features of false memories are frequently at the foreground of false memory research. However, it has become increasingly apparent that false memories also have positive consequences. In two experiments, we examined the positive consequences of false memories. Participants were visually presented with false memory word lists and received a recognition task. In a modified perceptual closure test, participants received degraded visual representations of words (false, true, and unrelated items) that became clearer over time. Participants had to identify them as fast as possible. Identifications based on false memories were significantly faster than those based on true memories and (un)related items. A roughly similar pattern was observed when no recognition task was used and when critical lures were replaced with other items (Experiment 2). Our results indicate that false memories can be beneficial for problem-solving tasks and counter the standard perspective that false memories are inherently negative in nature

The Spacetime Superalgebras from M-branes in M-brane Backgrounds

We derive the spacetime superalgebras explicitly from ``test'' M-brane actions in M-brane backgrounds to the lowest order in $\theta$ via canonical formalism, and discuss various BPS saturated configurations on the basis of their central charges which depend on the harmonic functions determined by the backgrounds. All the 1/4 supersymmetric intersections of two M-branes obtained previously are deduced from the requirement of the test branes to be so ``gauge fixed'' in the brane backgrounds as to preserve 1/4 supersymmetry. Furthermore, some of 1/2-supersymmetric bound states of two M-branes are deduced from the behavior of the harmonic functions in the limits of vanishing distances of the two branes. The possibilities of some triple intersections preserving 1/4 supersymmetry are also discussed.Comment: 15pages, Latex, Some mistakes are radically revised. Some references added. In v4 the proofs of the invariance of the actions are added, one reference is also added and some grammatical and spelling mistakes are corrected. In v5 some trivial mistakes corrected, two references also added agai