Myers Terms Research Articles

Classical holographic relations and alternative boundary conditions for Lovelock gravity

We obtain the classical holographic relation for the general Lovelock gravity and decompose the full Lagrangian into the bulk term and the surface term, expressed as a total derivative $\partial_\mu J^\mu$. By classical holographic relation, we mean that $J^\mu$ is determined completely by the bulk term. We find that the bulk term is not degenerate, or first-order in this foliation-independent approach. We then consider the Arnowitt-Deser-Misner (ADM) formalism where the foliation coordinate $w$ is treated as special. We obtain the classical holographic-degenerate relation with the first-order bulk term that does not involve higher than one derivative of $w$. For Einstein gravity, the two approaches lead to the same bulk term, but different ones for higher-order Lovelock gravities. The classical holographic-degenerate formulation in the ADM approach allows us to consider alternative boundary conditions in the variation principle with different Myers terms. We show in the semiclassical approximation that the black hole entropy in all cases is the same as the one obtained under the standard Dirichlet boundary condition. We also generalize the formalism to general $f(L_{\rm Lovelock}^{(k)})$-gravity.

On SYM theory and all order bulk singularity structures of BPS strings in type II theory

The complete forms of the S-matrix elements of a transverse scalar field, two world volume gauge fields, and a Potential Cn−1 Ramond–Ramond (RR) form field are investigated. In order to find an infinite number of t,s,(t+s+u)-channel bulk singularity structures of this particular mixed open-closed amplitude, we employ all the conformal field theory techniques to <VC−2Vϕ0VA0VA0>, exploring all the entire correlation functions and all order α′ contact interactions to these supersymmetric Yang–Mills (SYM) couplings. Singularity and contact term comparisons with the other symmetric analysis, <VC−1Vϕ0VA−1VA0> and <VC−1Vϕ−1VA0VA0> are also carried out in detail. Various couplings from pull-Back of branes, Myers terms and several generalized Bianchi identities should be taken into account to be able to reconstruct all order α′ bulk singularities of type IIB (IIA) superstring theory. Finally, we make a comment on how to derive without any ambiguity all order α′ contact terms of this S-matrix which carry momentum of RR in transverse directions.

On bulk singularity structures and all order α ′ contact terms of BPS string amplitudes

The entire form of the amplitude of three SYM ( involving two transverse scalar fields, a gauge field) and a potential $C_{n-1}$ Ramond-Ramond (RR) form field is found out. We first derive $<V_{C^{-2}} V_{A^{0}} V_{\phi ^{0}} V_{\phi ^{0}}>$ and then start constructing an infinite number of $t,s$ channel bulk singularity structures by means of all order $\alpha'$ corrections to pull-back of brane in an Effective Field Theory (EFT). Due to presence of the complete form of S-matrix, several new contact interactions as well as new couplings are explored. It is also shown that these couplings can be verified at the level of EFT by either the combinations of Myers terms, pull-back, Taylor expanded of scalar fields or the mixed combination of the couplings of this paper as well as employed Bianchi identities. For the first time, we also derive the algebraic and the complete form of the integrations for some arbitrary combinations of Mandelstam variables and for the most general case $\int d^2z |1-z|^{a} |z|^{b} (z - \bar{z})^{c} (z + \bar{z})^{3}$ on upper half plane as well.

On RR couplings, singularity structures and all order α′ contact interactions to BPS string amplitudes

We evaluate five point world-sheet string theory amplitudes of one transverse scalar field, two world volume gauge fields (and two transverse scalars, a gauge field) in the presence of a closed string Ramond-Ramond vertex operator in its symmetric picture. We carry out all the entire S-matrix elements of five point mixed RR-scalars/gauge fields <C −1 ϕ 0 A −1 A 0>, <C −1 ϕ −1 A 0 A 0>, <C −1 A 0 ϕ −1 ϕ 0> and <C −1 A −1 ϕ 0 ϕ 0> in detail and start comparing all order α′ contact interactions and singularities in both transverse and world volume directions. We explore the presence of various new couplings in string theory effective actions and find out their all order α′ higher derivative corrections in both type IIA and IIB. Ultimately we make various remarks for the singularities and contact terms whose RR momenta are embedded in transverse directions. α′ corrections to some of Myers terms are also addressed.

Janus field theories from multiple M2 branes

Based on the recent proposal of N = 8 superconformal gauge theories of the multiple M2 branes, we derive (2 + 1)-dimensional supersymmetric Janus field theories with a space-time dependent coupling constant. From the original Bagger-Lambert model, we get a supersymmetric field theory with a similar action to the N D2 branes, but the coupling varies with the space-time as a function of the light-cone coordinate, g(t + x). Half of the supersymmetries can be preserved. We further investigate the M2 brane action deformed by mass and Myers-like terms. In this case, the final Yang-Mills action is deformed by mass and Myers terms, and the coupling behaves as exp(μx) where μ is a constant mass parameter. Weak coupling gauge theory is continuously changed to strong coupling in the large x region.

Nonanticommutative deformation of Script N = 4 SYM theory: the Myers effect and vacuum states

We propose a deformation of ${\cal N}=4$ SYM theoery induced by nonanticommutative star product. The deformation introduces new bosonic terms which we identify with the corresponding Myers terms of a stack of D3-branes in the presence of a five-form RR flux. We take this as an indication that the deformed lagrangian describes D3-branes in such a background. The vacuum states of the theory are also examined. In a specific case where the U(1) part of the gauge field is nonvanishing the (anti)holomorphic transverse coordinates of the brane sit on a fuzzy two sphere. For a supersymmetric vacuum the antiholomorphic coordinates must necessarily commute. However, we also encounter non-supersymmetric vacua for which the antiholomorphic coordinates do not commute.

Brane-antibrane action from boundary string field theory

In this paper we give the boundary string field theory description of brane-antibrane systems. From the world-sheet action of brane-antibrane systems we obtain the tachyon potential and discuss the tachyon condensation exactly. We also find the world-volume action including the gauge fields. Moreover we determine RR-couplings exactly for non-BPS branes and brane-antibranes. These couplings are written by superconnections and correspond to K1(M) and K0(M) for the non-BPS branes and brane-antibranes, respectively. We also show that Myers terms appear if we include the transverse scalars in the boundary sigma model action.

Chern-Simons terms on noncommutative branes

We write down couplings of the fields on a single BPS Dp-brane with noncommutative world-volume coordinates to the RR-forms in type II theories, in a manifestly background independent way. This generalises the usual Chern-Simons action for a commutative Dp-brane. We show that the noncommutative Chern-Simons terms can be mapped to Myers terms on a collection of infinitely many D-instantons. We also propose Chern-Simons couplings for unstable non-BPS branes, and show that condensation of noncommutative tachyons on these branes leads to the correct Myers terms on the decay products.