In this note we investigate quantum aspects of the newly proposed theory of multiple membranes put forward by Bagger and Lambert. In particular we analyse the possibility of a finite renormalisation of the coupling at one loop.
This paper examines various aspects of the recently proposed theory of coincident membranes by Bagger and Lambert. These include the properties of open membranes and the resulting boundary theory with an interpretation in terms of the fivebrane and marginal supersymmetric deformations of the interactions with the relation to the holographic dual.
Motivated by a physical interpretation of its correlation functions as membrane scattering amplitudes, we re-address whether the Lorentzian BLG theory can be quantized such that it preserves SO(8) superconformal symmetry. We find that this appears to be possible. While the model seems to adequately reproduce protected quantities such as chiral primary amplitudes and the four derivative effective action, we conclude that, as understood at present, it gives a relatively unpractical parametrization of the IR dynamics of M2-branes.
We compute the tree-level potential between two parallel $p$-branes due to the exchange of scalars, gravitons and $(p+1)$-forms. In the case of BPS membranes in 4d $\mathcal{N}=1$ supergravity, this provides an interesting reinterpretation of the classical Cremmer et al. formula for the F-term scalar potential in terms of scalar, graviton and 3-form exchange. In this way, we present a correspondence between the scalar potential at every point in scalar field space and a system of two interacting BPS membranes. This could potentially lead to interesting implications for the swampland program by…
The exact quantum integrability aspects of a sector of the membrane is investigated. It is found that spherical membranes moving in flat target spacetime backgrounds admit a class of integrable solutions linked to SU(infty) SDYM equations (dimensionally reduced to one temporal dimension). After a suitable ansatz, the SDYM equations can be recast in the form of the continuous Toda molecule equations whose symmetry algebra is the dimensional reduction of the W (infty} plus {\bar W}(infty} algebra. The latter algebra is explicitly constructed. Highest weight representations are built directly fro…
We study certain aspects of noncommutativity in field theory, strings and membranes. We analyse the dynamics of an open membrane whose boundary is attached to p-branes. Noncommutative features of the boundary string coordinates are revealed by algebraic consistency arguments. Next, we derive Seiberg-Witten-type maps relating currents and their divergences in nonabelian U(N) noncommutative gauge theory with the corresponding expressions in the ordinary (commutative) description. We then exploit these maps to obtain the O(θ) structure of the commutator anomalies in noncommutative electrodynamics…
In this note we discuss various classical membrane solutions in AdS$_4$ spacetime: simple embeddings given by polynomials in ambient space, solutions with non-linear waves, and piecewise linear solutions.
Mass deformations of supersymmetric Yang-Mills theories in three spacetime dimensions are considered. The gluons of the theories are made massive by the inclusion of a non-local gauge and Poincare invariant mass term due to Alexanian and Nair, while the matter fields are given standard Gaussian mass-terms. It is shown that the dimensional reduction of such mass deformed gauge theories defined on $R^3$ or $R\times T^2$ produces matrix quantum mechanics with massive spectra. In particular, all known massive matrix quantum mechanical models obtained by the deformations of dimensional reductions o…
In this note, we have extended the result of \citep{radiation} to calculate the membrane stress tensor up to ${\cal O}\left(\frac{1}{D}\right)$ localized on the codimension-one membrane world volume propagating in asymptotically at/AdS/dS space-time. We have shown that the subleading order membrane equation follows from the conservation equation of this stress tensor.
In this note, we discuss membrane scattering from the three dimensional N=8 superconformal theory with SO(8) global symmetry constructed by Bagger-Lambert and Gustavsson. We discuss whether the one loop effective potential consistently reproduces the Newton potential of membranes moving in an eleven dimensional orbifold space.
This note covers various aspects of recent attempts to describe membranes ending on fivebranes using fuzzy geometry. In particular, we examine the Basu-Harvey equation and its relation to the Nahm equation as well as the consequences of using a non-associative algebra for the fuzzy three-sphere. This produces the tantalising result that the fuzzy funnel solution corresponding to Q coincident membranes ending on a five-brane has $Q^{3/2}$ degrees of freedom.
The motion of test membranes on which the group $G$ of isometries of a spacetime $M$ acts has been considered in general settings. It has been shown that the configuration of Nambu-Goto membranes is described by the Nambu-Goto membranes in the quotient manifold $M/G$ with an appropriate projected metric if (i) $G$ is Abelian, (ii) $G$ is semisimple and compact, or (iii) the orthogonal distribution of the orbit of $G$ is integrable, but in general not. It has also been shown that a similar result holds when the membranes couple with scalar maps or differential form fields.
These lecture notes introduce the multiple membrane theories known as BLG and ABJM. We assume the reader is familiar with string theory, but not with M-theory, 11-dimensional supergravity or membranes. We therefore start with a background on M-theory and its extended objects before discussing BLG and ABJM. The link to string theory via dimensional reduction will be maintained throughout.
This thesis consists of two parts. In the first part we investigate the worldvolume supersymmetry algebra of multiple membrane theories. We begin with a description of M-theory branes and their intersections from the perspective of spacetime and worldvolume supersymmetry algebras. We then provide an overview of the recent work on multiple M2-branes focusing on the Bagger-Lambert theory and its relation to the Nambu-Poisson M5-brane and the ABJM theory. The worldvolume supersymmetry algebras of these theories are explicitly calculated and the charges interpreted in terms of spacetime intersecti…
We re-examine the question of the stability of quantum supermembranes. In the past, the instability of supermembranes was established by using a regulator, i.e. approximating the membrane by SU(N) super Yang-Mills theory and letting $N \rightarrow \infty$. In this paper, we (a) show that the instability persists even if we directly examine the continuum theory (b) give heuristic arguments that even a theory of unstable membranes at the Planck length may still be compatible with experiment (c) resolve a certain puzzling discrepancy between earlier works on the stability of supermembranes. Prese…
In this note we study M5-branes in the multiple membrane action which is recently proposed by Aharony-Bergman-Jafferis-Maldacena. We write down the N=6 supersymmetry transformation of the action and obtain 1/2 BPS equations and their solutions. They are expected to represent membranes ending on a M5-brane. We also consider the M5-M2 bound state in the action.
In the first half of this note, after briefly motivating and reviewing membrane field theories, we consider their BPS funnel solutions. We discuss some aspects of embedding M-theory fuzzy funnels in these theories. In the second half, we focus on ABJM theory and explain a test of AdS4/CFT3 based on integrability. We discuss a numerical mismatch at one loop in worldsheet perturbation theory and its possible resolutions.
At the core of nonperturbative theories of quantum gravity lies the holographic encoding of bulk data in large matrices. At present this mapping is poorly understood. The plane wave matrix model provides a laboratory for isolating aspects of this problem in a controlled setting. At large boosts, configurations of concentric membranes become superselection sectors, whose exact spectra are known. From the bulk point of view one expects product states of individual membranes to be contained within the full spectrum. However, for non-BPS states this inclusion relation is obscured by Gauss law cons…
The recently introduced anomaly-free twistor string in four dimensions is shown to be defined not just in flat but also in curved twistor space. Further, arguments are given that the classical limit of the corresponding string field theory, if it exists, is related to general relativity, in particular to the Isenberg and Yasskin construction using teleparallel gravity. For spacetimes of Petrov type D with two shear-free null congruences the construction can be simplified using two-dimensional twistor manifolds.
The exact quantum integrability aspects of a sector of the membrane is investigated. It is found that spherical membranes ( in the lightcone gauge) moving in flat target spacetime backgrounds admit a class of integrable solutions linked to $SU(\infty)$ SDYM equations ( dimensionally reduced to one temporal dimension) which, in turn, are related to Plebanski 4D SD Gravitational equations. A further rotational Killing-symmetry reduction yields the 3D continuous Toda theory. It is precisely the latter which bears a direct relationship to non critical $W_\infty$ string theory. The expected critica…
We carry out a perturbative study of the Leigh-Strassler deformed N=4 SYM theory in order to verify that the trihedral Delta(27) symmetry holds in the quantum theory. We show that the Delta(27) symmetry is preserved to two loops (at finite N) by explicitly computing the superpotential. The perturbative superpotential is not holomorphic in the couplings due to finite contributions. However, there exist coupling constant redefinitions that restore holomorphy. Interestingly, the same redefinitions appear (in the work of Jack, Jones and North[hep-ph/9603386]) if one requires the three-loop anomalo…
We consider a novel class of Weyl-conformally invariant p-brane theories which describe intrinsically light-like branes for any odd world-volume dimension, hence the acronym WILL-branes (Weyl-Invariant Light-Like branes). We discuss in some detail the properties of WILL-brane dynamics which significantly differs from ordinary Nambu-Goto brane dynamics. We provide explicit solutions of WILL-membrane (i.e., p=2) equations of motion in arbitrary D=4 spherically symmetric static gravitational backgrounds, as well as in product spaces of interest in Kaluza-Klein context. In the first case we find t…
We introduce and study in some detail the properties of a novel class of Weyl-conformally invariant p-brane theories which describe intrinsically lightlike branes for any odd world-volume dimension. Their dynamics significantly differs from that of the ordinary (conformally non-invariant) Nambu-Goto p-branes. We present explicit solutions of the Weyl-invariant lightlike brane- (WILL-brane) equations of motion in various gravitational models of physical relevance exhibiting various new phenomena. In D=4 the WILL-membrane serves as a material and charged source for gravity and electromagnetism i…
This is a short arrangement of notes on D-branes, offered as an embellishment of five lectures which were presented at the 1998 Trieste Spring School entitled ``Non-Perturbative Aspects of String Theory and Supersymmetric Gauge Theory''. There is a good number of collections of pedagogical notes on D-branes in the literature, and since space here is limited, no attempt will be made to cover all of the introductory material again. Instead, the notes cover selected topics and themes in string theory and M-theory, emphasizing how certain technical aspects of D-branes play a role. The subject is d…