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In this note we provide a new perspective on the topological parts of several action functionals in string and M-theory. We show that rationally these can be viewed as large gauge transformations corresponding to variations of higher structures, such as String, Fivebrane, and Ninebrane structures., References and material on the heterotic case added, published version. arXiv admin note: text overlap with arXiv:1612.06983

It was recently pointed out in \cite{Kim:2015hya} that AdS$_6$ solutions in IIB theory enjoy an extended symmetry structure and the consistent truncation to $D=4$ internal space leads to a nonlinear sigma model with target $SL(3,\mathbb{R})/SO(2,1)$. We continue to study the purely bosonic $D=4$ effective action, and elucidate how the addition of scalar potential term still allows Killing spinor equations in the absence of gauge fields. In particular, the potential turns out to be a single diagonal component of the coset representative. Furthermore, we perform a general analysis of the integrability conditions of Killing spinor equations and establish that the effective action can be in fact generalized to arbitrary sizes and signatures, e.g. with target $SL(n,\mathbb{R})/SO(p,n-p)$ and the scalar potential expressible by a single diagonal component of the coset representative. We also comment on a similar construction and its generalizations of effective $D=5$ purely bosonic non-linear sigma model action related to AdS$_6$ in M-theory., v2: 17 pages, version published in PLB

We consider N = 1 F-theory and Type IIB orientifold compactifications and derive new α ′ corrections to the four-dimensional effective action. They originate from higher derivative corrections to eleven-dimensional supergravity and survive the M-theory to F-theory limit. We find a correction to the Kahler potential depending on the volume of a non-trivial intersection curve of seven-branes. At weak string coupling this correction arises from the intersection of D7-branes with the O7-plane. We also analyze a four-dimensional higher curvature correction.

In our previous papers we have shown how Lifshitz-like space-time (space-time having a Lifshitz scaling along with a hyperscaling violation) can arise by taking near horizon limits of certain intersecting solutions (F-string with D$p$-branes and also with two D-branes) of string theory. In this paper we construct intersecting bound state solutions in the form of NS5-D$p$-branes (with $1\leq p \leq 6$) of type II string theories. These are 1/4 BPS and threshold bound states unlike the known NS5-D$p$ bound states which are 1/2 BPS and non-threshold. We show that the near horizon limits of these solutions also lead to Lifshitz-like space-time with the dynamical scaling exponent $z=0$ and the hyperscaling violation exponent $\theta=9-p$. The spatial dimension of the boundary theory is $d=7-p$. The dilatons in these theories are not constant in general (except for $p=5$) and therefore produce RG flows. So, we also consider the strong coupling phases of these theories and find that these phases also have similar Lifshitz-like structures, except for $p=2$, where it has an AdS$_3$ structure., Comment: 12 pages, no figure; v2: Added references; v3: more clarifications added, version to appear in Phys. Lett. B

We study the production of primordial magnetic fields in inflationary models in type IIB string theory where the role of the inflaton is played by a Kahler modulus. We consider various possibilities to realise the Standard Model degrees of freedom in this setting and explicitly determine the time dependence of the inflaton coupling to the Maxwell term in the models. Using this we determine the strength and scale dependence of the magnetic fields generated during inflation. The usual "strong coupling problem" for primordial magnetogesis manifests itself by cycle sizes approaching the string scale, this appears in a certain class of fibre inflation models where the standard model is realised by wrapping D7-branes on cycles in the geometric regime., 18 pages, 4 figures

With the help of a generalized form of the metric ansatz found for the single-charge case in a previous work [S.Q. Wu, Phys. Rev. D 83 (2011) 121502(R)], I adopt a simple algorithm to construct the most general nonextremal rotating charged black hole solutions in five-dimensional U ( 1 ) 3 gauged supergravity. The general solution that is interesting for testing the AdS5/CFT4 correspondence in M-theory, is characterized by its mass, two unequal rotation parameters, three different U ( 1 ) charges, and a negative cosmological constant. The metric ansatz is very universal and illuminative, it is not only especially suitable for constructing solutions with multiple different electric charges in (un)gauged supergravities, but also for other dilatonic gravity theory.

The most general class of warped AdS5 x M6 supersymmetric solutions in D=11 supergravity permit a consistent truncation to D=5 N=2 minimal gauged supergravity. Here we extend this truncation, for a particular subclass of M6 manifolds, to D=5 N=4 gauged supergravity coupled to two vector multiplets. We obtain the reduction ansatz by T-duality of a recently discussed type IIB truncation on a generic Sasaki-Einstein five-fold, which becomes non-trivial in D=11 and displays non-standard features due to the G-structure of the internal M6. Using this truncation, we construct two new classes of warped and unwarped non-supersymmetric AdS5 M-theory backgrounds. We also comment on possible extensions of the reduction ansatz to the general class of M6 geometries., Comment: Seven double column pages; v2: Acknowledgement added, version to be published in Phys. Lett. B

This paper considers anomaly cancellation for eleven-dimensional supergravity on a manifold with boundary and theories related to heterotic $M$-theory. The Green-Schwarz mechanism is implemented without introducing distributions. The importance of the supersymmetry anomaly in constructing the low energy action is discussed and it is argued that a recently proposed action for heterotic $M$-theory gives a supersymmetric theory to all orders in the gravitational coupling $\kappa$., Comment: 4 pages LaTeX

We obtain the solution for non-extremal charged rotating black holes in seven-dimensional gauged supergravity, in the case where the three rotation parameters are set equal. There are two independent charges, corresponding to gauge fields in the U(1)xU(1) abelian subgroup of the SO(5) gauge group. A new feature in these solutions, not seen previously in lower-dimensional examples, is that the first-order "odd-dimensional self-duality" equation for the 4-form field strength plays a non-trivial role. We also study the BPS limit of our solutions where the black holes become supersymmetric. Our results are of significance for the AdS_7/CFT_6 correspondence in M-theory., Comment: Latex, 12 pages, typos corrected and a reference added

We study inflationary solutions in the M-theory. Including the fourth-order curvature correction terms, we find three generalized de Sitter solutions, in which our 3-space expands exponentially. Taking one of the solutions, we propose an inflationary scenario of the early universe. This provides us a natural explanation for large extra dimensions in a brane world, and suggests some connection between the 60 e-folding expansion of inflation and TeV gravity based on the large extra dimensions., Comment: 12 pages, 2 figures, v2: figures corrected, v3: refs. added, version to appear in PLB, ps file is available from http://www-het.phys.sci.osaka-u.ac.jp/ohta/r4_inf.ps.gz

We study the hidden symmetries arising in the dimensional reduction of d=5, N=2 supergravity to three dimensions. Extending previous partial results for the bosonic part, we give a derivation that includes fermionic terms, shedding light on the appearance of the local hidden symmetry SO(4) in the reduction., 11 pages LaTeX, uses elsart and amssymb

We describe the set of generalized Poincare and conformal superalgebras in D=4,5 and 7 dimensions as two sequences of superalgebraic structures, taking values in the division algebras R, C and H. The generalized conformal superalgebras are described for D=4 by OSp(1;8| R), for D=5 by SU(4,4;1) and for D=7 by U_\alpha U(8;1|H). The relation with other schemes, in particular the framework of conformal spin (super)algebras and Jordan (super)algebras is discussed. By extending the division-algebra-valued superalgebras to octonions we get in D=11 an octonionic generalized Poincare superalgebra, which we call octonionic M-algebra, describing the octonionic M-theory. It contains 32 real supercharges but, due to the octonionic structure, only 52 real bosonic generators remain independent in place of the 528 bosonic charges of standard M-algebra. In octonionic M-theory there is a sort of equivalence between the octonionic M2 (supermembrane) and the octonionic M5 (super-5-brane) sectors. We also define the octonionic generalized conformal M-superalgebra, with 239 bosonic generators., Comment: 14 pages, LaTeX

We generalize noncommutative gauge theory using Nambu-Poisson structures to obtain a new type of gauge theory with higher brackets and gauge fields. The approach is based on covariant coordinates and higher versions of the Seiberg-Witten map. We construct a covariant Nambu-Poisson gauge theory action, give its first order expansion in the Nambu-Poisson tensor and relate it to a Nambu-Poisson matrix model., Several minor typos corrected, references added

We propose a six-dimensional framework to calculate the supersymmetric index of M-theory 5-branes wrapped on a six-manifold with product topology $M_4\times T^2$, where $M_4$ is a holomorphic 4-cycle in a Calabi-Yau three-fold. This is obtained by zero-modes counting of the self-dual tensor contribution plus ``little'' string states and correctly reproduces the known results which can be obtained by shrinking or blowing the $T^2$ volume parameter. We also extract the geometric moduli space of the multi M5-brane system and infer the generic structure of the supersymmetric index for more general geometries., 1+13 pages; v2: introduction expanded, to appear in PLB

Some spatially homogeneous Bianchi type I cosmological models filled with homogeneous `electric' p -form fields are shown to mimic the never-ending oscillatory behaviour of generic string cosmologies established recently. The validity of the `Kasner-free-flights plus collisions-on-potential-walls' picture is also illustrated in the case of known, non-chaotic, superstring solutions.

We discuss Poincare three-brane solutions in D=5 M-Theory compactifications on Calabi-Yau (CY) threefolds with G-fluxes. We show that the vector moduli freeze at an attractor point. In the case with background flux only, the spacetime geometry contains a zero volume singularity with the three-brane and the CY space shrinking simultaneously to a point. This problem can be avoided by including explicit three-brane sources. We consider two cases in detail: a single brane and, when the transverse dimension is compactified on a circle, a pair of branes with opposite tensions., 14 pages, final version

We study BPS dominated loop amplitudes in M-theory on T^2. For this purpose we generalize the concept of helicity supertraces to nine spacetime dimensions. These traces distinguish between various massive supermultiplets and appear as coefficients in their one-loop contributions to n-graviton scattering amplitudes. This can be used to show that only ultrashort BPS multiplets contribute to the R^4 term in the effective action, which was first computed by Green, Gutperle and Vanhove. There are two inequivalent ultrashort BPS multiplets which describe the Kaluza-Klein states and the wrapped membranes that cover the torus a number of times. From the perspective of the type-II strings they correspond to momentum and winding states and D0 or D1 branes., Comment: 15 pages

In this paper, relying on previous results of one of us on harmonic analysis, we derive the complete spectrum of Osp(3|4) X SU(3) multiplets that one obtains compactifying D=11 supergravity on the unique homogeneous space N^{0,1,0} that has a tri-sasakian structure, namely leads to N=3 supersymmetry both in the four-dimensional bulk and on the three-dimensional boundary. As in previously analyzed cases the knowledge of the Kaluza Klein spectrum, together with general information on the geometric structure of the compact manifold is an essential ingredient to guess and construct the corresponding superconformal field theory. This is work in progress. As a bonus of our analysis we derive and present the explicit structure of all unitary irreducible representations of the superalgebra Osp(3|4) with maximal spin content s_{max}>=2.

We analyze the relation between the large N limit of 6 dimensional superconformal field theories with eight supercharges and M theory on orbifolds of AdS_7xS^4. We use the known spectrum of Kaluza-Klein harmonics of supergravity on AdS_7xS^4 and we take their orbifold projection to get information about the chiral primary operators of 6 dimensional SCFT which is realized on the worldvolume of M5 brane sitting at the orbifold singularities.

It has been known that D=5 simple supergravity resembles D=11 supergravity in many respects. We present their further resemblances in (1) the duality groups upon dimensional reduction, and (2) the worldsheet structure of the solitonic string of the D=5 supergravity. We show that the D=3, G_{2(+2)}/SO(4) (bosonic) nonlinear sigma model is obtained by using Freudenthal's construction in parallel to the derivation of the D=3, E_{8(+8)}/SO(16) sigma model from D=11 supergravity. The zero modes of the string solution with unbroken (4,0) supersymmetry consist of three (non-chiral) scalars, four Majorana-Weyl spinors of the same chirality and one chiral scalar, which suggests a duality to a certain six-dimensional chiral string theory. The worldsheet gravitational anomaly indicates a quantum correction to the Bianchi identity for the dualized two-form gauge field in the bulk just like the M5-brane case., Comment: 12 pages, references added

We investigate whether DLCQ of M-theory can be defined as a limit of M-theory compactified on an almost light-like circle. This is of particular interest since the proofs of the matrix description of M-theory by Seiberg and Sen rely on this assumption. By the standard relation between M-theory on $S^1$ and IIA string theory, we translate this question into the corresponding one about the existence of the light-like limit of IIA superstring theory for any string coupling $g_s$. We argue that perturbative string loop amplitudes should have a finite and well-defined light-like limit provided the external momenta are chosen to correspond to a well-defined DLCQ set-up. On the non-perturbative side we consider states and amplitudes. We show that an appropriate class of non-perturbative states (wrapped D-branes) precisely have the right light-like limit. We give some indications that non-perturbative corrections to string amplitudes, too, may behave as required in the light-like limit. Having perturbative and non-perturbative evidence, this suggests that type IIA superstring theory as a whole has a well-defined light-like limit (for any string coupling $g_s$) and hence that the same is true for M-theory., 10 pages, uses PHYZZX, no figures, references added

We discuss supersymmetric Yang-Mills theory dimensionally reduced to zero dimensions and evaluate the SU(2) and SU(3) partition functions by Monte Carlo methods. The exactly known SU(2) results are reproduced to very high precision. Our calculations for SU(3) agree closely with an extension of a conjecture due to Green and Gutperle concerning the exact value of the SU(N) partition functions., Comment: 13 pages, LaTeX, REVTEX, correction of eq.(26) for D=4,6 and non-prime values of N

We consider brane configurations in M-theory describing N=1 supersymmetric gauge theories and using the parametric representation of the brane configurations, we calculate the superpotentials for various cases including multiple gauge groups or fermions. For SU(n) N=1 SQCD with $N_f$ fermion case ($N_f < N_c)$, we find that the superpotential from M-theory and the gauge theory agree precisely. This gives a direct evidence of the validity of Witten's M-theory method for calculating the super potential., 15pages, latex, typos corrected, a line regarding M\"obius transformation in page 4 and angle dependence in page 12 corrected

We investigate the zero modes of the Kaluza-Klein monopole in M-theory and show that the Born-Infeld action and the Chern-Simons term of a D6-brane are reproduced to quadratic order in the field strength of the U(1) field on the brane., 11 pages, LaTeX

We compactify $M$-theory on a Calabi-Yau manifold to five dimensions by wrapping the membrane and fivebrane solitons of the eleven-dimensional supergravity limit around Calabi-Yau two-cycles and four-cycles respectively. We identify the perturbative and non-perturbative BPS states thus obtained with those of heterotic string theory compactified on $K3\times S^1$. Quantum aspects of the five-dimensional theory are discussed., Comment: 12 pages, 1 figure, uses harvmac, epsf

A proposed duality between type IIB superstring theory on R^9 X S^1 and a conjectured 11D fundamental theory (``M theory'') on R^9 X T^2 is investigated. Simple heuristic reasoning leads to a consistent picture relating the various p-branes and their tensions in each theory. Identifying the M theory on R^{10} X S^1 with type IIA superstring theory on R^{10}, in a similar fashion, leads to various relations among the p-branes of the IIA theory., Comment: 13 pages; latex

We give a simple derivation of BPS condition of string junction from M theory, Comment: 6 pages, Latex, 2 figures

We show the complete cancellation of gauge and gravitational anomalies in the M-theory of Horava and Witten using their boundary contribution, and a term coming from the existence of two and five-branes. A factor of three discrepancy noted in an earlier work is resolved. We end with a comment on flux quantization., 5 pages, Latex, typos corrected, minor notation change in eq. (0.7). Version to be published in Phys. Lett. B

Noncommutative inflation is based upon the consideration of some effects of the space-time uncertainty principle motivated by ideas from string/M theory. The CMB anisotropies may carry a signature of this very early Universe correction from the space-time uncertainty principle and can be used to place constraints on the parameters of the noncommutative inflation model. In this paper we analyze the noncommutative chaotic inflation model by means of the WMAP three year results. We show that the noncommutative chaotic inflation model can produce a large negative running of spectral index within a reasonable range of $e$-folding number $N$, provided that the value of $p$ in the potential $V(\phi)\propto \phi^p$ is enhanced roughly to $p\sim 12-18$. Applying a likelihood analysis to the WMAP results, we find the best-fit values of parameters for the noncommutative chaotic inflation model. In addition, this model predicts a rather big gravitational wave which may be tested by the upcoming experiments., Comment: 8 pages, 3 figures;accepted for publication in Phys. Lett. B