We consider the non-relativistic limit of general relativity coupled to a (p+1)-form gauge field and a scalar field in arbitrary dimensions and investigate under which conditions this gives rise to a Poisson equation for a Newton potential describing Newton-Cartan gravity outside a massive p-dimensional extended object, a so-called p-brane. Given our Ansatz, we show that not all the p-branes satisfy the required conditions. We study theories whose dynamics is defined by a Lagrangian as well as systems that are defined by a set of equations of motion not related to a Lagrangian. We show that, within the Lagrangian approach, a Poisson equation can be obtained provided that the coupling of the scalar field is fine-tuned such that the non-relativistic Lagrangian is invariant under an emerging local dilatation symmetry. On the other hand, we demonstrate that in the absence of a Lagrangian a Poisson equation can be obtained from a set of equations of motion that is not dilatation invariant. We discuss how our Ansatz could be generalized such as to include more p-branes giving rise to a Poisson equation.

We construct the M5-brane limit of eleven-dimensional supergravity. The resulting action is invariant under Galilean boosts and has a local scale symmetry. We also consider the limit of the equations of motion where we recover a Poisson-like equation arising from an M5-brane source but which does not follow from the non-relativistic action. We argue that the resulting theory describes gravitational fluctuations around a stack of M5-branes, represented by a trivial Minkowskian spacetime, but where the number of M5-branes is determined by the flux of a Lagrange multiplier field.

We study a non-relativistic limit of 11-dimensional supergravity. This limit leads to a theory with an underlying membrane Newton-Cartan geometry. Consistency of the non-relativistic limit requires the imposition of constraints, requiring that certain bosonic and fermionic torsions and curvatures vanish. We investigate the implications of two versions of these constraints. In one version, we keep only 16 supersymmetry transformations, leading to a simple (purely bosonic) constraint structure but an unusual realisation of the supersymmetry algebra which does not close into diffeomorphisms. In the other, we keep all 32 supersymmetry transformations. This requires a complicated sequence of bosonic and fermionic constraints, eventually involving three derivatives of bosonic fields. We argue, with a linearised calculation, that this sequence of constraints terminates. Furthermore, we show that there exists a family of supersymmetric solutions satisfying these constraints, containing the non-relativistic limit of the M2 supergravity solution recently obtained by Lambert and Smith as a background relevant for non-relativistic holography.

We study D-dimensional p-brane Galilean geometries via the intrinsic torsion of the adapted connections of their degenerate metric structure. These non-Lorentzian geometries are examples of G-structures whose characteristic tensors consist of two degenerate 'metrics' of ranks ( p + 1 ) and ( D - p - 1 ) . We carry out the analysis in two different ways. In one way, inspired by Cartan geometry, we analyse in detail the space of intrinsic torsions (technically, the cokernel of a Spencer differential) as a representation of G, exhibiting for generic (p, D) five classes of such geometries, which we then proceed to interpret geometrically. We show how to re-interpret this classification in terms of ( D - p - 2 )-brane Carrollian geometries. The same result is recovered by methods inspired by similar results in the physics literature: namely by studying how far an adapted connection can be determined by the characteristic tensors and by studying which components of the torsion tensor do not depend on the connection. As an application, we derive a gravity theory with underlying p-brane Galilean geometry as a non-relativistic limit of Einstein-Hilbert gravity and discuss how it gives a gravitational realisation of some of the intrinsic torsion constraints found in this paper. Our results also have implications for gravity theories with an underlying ( D - p - 2 )-brane Carrollian geometry.

In this work we consider heterotic-gravity as the low-energy approximation to heterotic string theory. We define a consistent non-relativistic limit of heterotic gravity that includes the Yang-Mills Chern-Simons term. We perform three tests on the heterotic limit: we use it to (i) derive the non-relativistic transformation rules, (ii) show the existence of a finite non-relativistic heterotic action and (iii) obtain the longitudinal non-relativistic T-duality rules. We show that in all these cases the limit procedure is well defined, free of divergences and leads to consistent non-trivial results. We comment on the interpretation of the T-duality rules in terms of a heterotic non-relativistic geometry underlying non-relativistic heterotic string theory.

Using carefully chosen projections, we consider different Carroll limits of relativistic Dirac fermions in any spacetime dimensions. These limits define Carroll fermions of two types: electric and magnetic. The latter type transforms as a reducible but indecomposable representation of the Carroll group. We also build action principles for all Carroll fermions we introduce; in particular, in even dimensions we provide an action principle for a minimal magnetic Carroll fermion, having the same number of components as a Dirac spinor. We then explore the coupling of these fermions to magnetic Carroll gravity in both its first-order and second-order formulations.

Abstract We consider spacetime metrics with a given (but quite generic) dependence on a dimensionful parameter such that in the 0 and ∞ limits of that parameter the metric becomes singular. We study the isometry groups of the original spacetime metrics and of the singular metrics that arise in the limits and the corresponding symmetries of the motion of p-branes evolving in them, showing how the Killing vectors and their Lie algebras can be found in general. We illustrate our general results with several examples which include limits of anti-de Sitter spacetime in which the holographic screen is one of the singular metrics and of pp-waves.

We consider different Carroll limits of relativistic Dirac fermions in any spacetime dimensions. One limit leads to Carroll fermions that are inert under internal Carroll boosts. We call these fermions electric Carroll fermions. Another limit makes use of projection operators and leads to a second type of Carroll fermion, called magnetic, that does transform non-trivially under Carroll boosts as a reducible but indecomposable representation of the Carroll group. We construct actions for both electric and magnetic Carroll fermions. In particular, in even dimensions we construct an action for a minimal magnetic Carroll fermion that has the same number of components as a Dirac spinor.

Incompressibility plays a key role in the geometric description of fractional quantum Hall fluids. It is naturally related to quantum area-preserving diffeomorphisms and the underlying Girvin-MacDonald-Plazman algebra, which gives rise to an emergent nonrelativistic massive spin-2 mode propagating in the bulk. The corresponding metric tensor can be identified with a nematic order parameter for the bulk states. In the linearized regime with a flat background, it has been shown that this mode can be described by a spin-2 Schr & ouml;dinger action. However, quantum area-preserving diffeomorphisms also suggest the existence of higher-spin modes that cannot be described through nematic fractional quantum Hall states. Here, we consider p-atic Hall phases, in which the corresponding p-atic order parameters are related to higher-rank symmetric tensors. We then show that in this framework, nonrelativistic massive chiral higher-spin fields naturally emerge and that their dynamics is described by higher-spin Schr & ouml;dinger actions. We finally show that these effective actions can be derived from relativistic massive higher-spin theories in 2 + 1 dimensions after taking a nonrelativistic limit.

We consider spacetime metrics with a given (but quite generic) dependence on a dimensionful parameter such that in the 0 and infinity limits of that parameter the metric becomes singular. We study the isometry groups of the original spacetime metrics and of the singular metrics that arise in the limits and the corresponding symmetries of the motion of p-branes evolving in them, showing how the Killing vectors and their Lie algebras can be found in general. We illustrate our general results with several examples which include limits of anti-de Sitter spacetime in which the holographic screen is one of the singular metrics and of pp-waves.

Motivated by old and new developments in non-relativistic string theory, we show that there exists a consistent non-relativistic limit of eleven-dimensional supergravity. Before taking the limit we give a short review of the underlying Membrane Newton-Cartan geometry. This geometry is a particular extension of the Newton-Cartan geometry in the sense that the two nondegenerate metrics of Newton-Cartan geometry (one to measure time intervals and another one to measure spatial distances) are replaced by two nondegenerate metrics of rank 3 and rank 8, respectively. An important role in describing this geometry and in the consistency of the limit is played by the so-called intrinsic torsion tensor components. These are the components of the torsion tensor that are independent of the spin-connection. After expanding the action of eleven-dimensional supergravity as a power series of a contraction parameter, we show how the different divergences that arise when taking the limit can be tamed. We furthermore show how the divergences that arise in expanding the supersymmetry rules can be controlled by imposing a supersymmetric set of constraints. This leads to a Membrane Newton-Cartan supergravity theory where the Newton potential can be identified with the component of the 3-form of eleven-dimensional supergravity that points in the three directions corresponding to the rank 3 degenerate metric.

We review both the kinematics and dynamics of non-lorentzian theories and their associated geometries. First, we introduce non-lorentzian kinematical spacetimes and their symmetry algebras. Next, we construct actions describing the particle dynamics in some of these kinematical spaces using the method of nonlinear realisations. We explain the relation with the coadjoint orbit method. We continue discussing three types of non-lorentzian gravity theories: Galilei gravity, Newton-Cartan gravity and Carroll gravity. Introducing matter, we discuss electric and magnetic non-lorentzian field theories for three different spins: spin-0, spin-1/2 and spin-1, as limits of relativistic theories.

We discuss the generalized Newton–Cartan geometries that can serve as gravitational background fields for particles and strings. In order to enable us to define affine connections that are invariant under all the symmetries of the structure group, we describe torsionful geometries with independent torsion tensors. A characteristic feature of the non-Lorentzian geometries we consider is that some of the torsion tensors are so-called ‘intrinsic torsion’ tensors. Setting some components of these intrinsic torsion tensors to zero leads to constraints on the geometry. For both particles and strings, we discuss various such constraints that can be imposed consistently with the structure group symmetries. In this way, we reproduce several results in the literature.

We derive the action and symmetries of the bosonic sector of non-Lorentzian IIB supergravity by taking the non-relativistic string limit. We find that the bosonic field content is extended by a Lagrange multiplier that implements a restriction on the Ramond-Ramond fluxes. We show that the SL(2, R) transformation rules of non-Lorentzian IIB supergravity form a novel, nonlinear polynomial realization. Using classical invariant theory of polynomial equations and binary forms, we will develop a general formalism describing the polynomial realization of SL(2, R) and apply it to the special case of non-Lorentzian IIB supergravity. Using the same formalism, we classify all the relevant SL(2, R) invariants. Invoking other bosonic symmetries, such as the local boost and dilatation symmetry, we show how the bosonic part of the non-Lorentzian IIB supergravity action is formed uniquely from these SL(2, R) invariants. This work also points towards the concept of a non-Lorentzian bootstrap, where bosonic symmetries in non-Lorentzian supergravity are used to bootstrap the bosonic dynamics in Lorentzian supergravity, without considering the fermions.

We give an overview of the different non-Lorentzian supergravity theories in diverse dimensions that have been constructed in recent years. After giving a detailed discussion of non-Lorentzian geometries as compared to Lorentzian geometries, we outline some of the construction methods that have been applied to obtain non-Lorentzian supergravity. Explicit results are given for non-Lorentzian supergravity theories in three and ten dimensions.

Motivated by non-relativistic string theory, we give a classification of D -dimensional generalized Galilean geometries. They are an extension of the Galilean geometry in the sense that the two non-degenerate metrics of Galilean geometry (one to measure time intervals and another one to measure spatial distances) are replaced by two non-degenerate metrics of rank p + 1 and rank D - p - 1 , respectively, with p = 0 , 1 , ⋯ , D - 1 . To classify these generalized geometries an important role is played by the so-called intrinsic torsion tensor indicating that this particular torsion is independent of the spin-connection. We show that there is a finite way of setting some of these intrinsic torsion tensors equal to zero and that this leads to a classification of the generalized Galilean geometries. Moreover, we show how some (but not all) of the generalized Galilean geometries that we find can be obtained by taking a special limit of general relativity.

We exhibit a new method of constructing non-Lorentzian models by applying a method we refer to as starting from a so-called seed Lagrangian. This method typically produces additional constraints in the system that can drastically alter the physical content of the model. We demonstrate our method for particles, scalars and vector fields.

We identify the proper geometry underlying non-relativistic string theory as 'String Newton-Cartan Gravity'.It has the distinguishing feature that one-dimensional foliation in Newton-Cartan geometry is replaced by a two-dimensional foliation on the target space.We discuss some basic properties of the string Newton-Cartan space-time, in particular it's behaviour under T-duality transformations.This leads to interesting nonrelativistic conformal field theories at the boundary that have applications in condensed matter physics.

We investigate how SL(2,Z) duality is realized in nonrelativistic type IIB superstring theory, which is a self-contained corner of relativistic string theory. Within this corner, we realize manifestly SL(2,Z)-invariant (p, q)-string actions. The construction of these actions imposes a branching between strings of opposite charges associated with the two-form fields. The branch point is determined by these charges and the axion background field. Both branches must be incorporated in order to realize the full SL(2,Z) group. Besides these string actions, we also construct D-instanton and D3-brane actions that manifestly realize the branched SL(2,Z) symmetry.

We construct the basic Neveu-Schwarz (NS) brane solutions of non-relativistic string theory using longitudinal T-duality as a solution generating technique. Extending the NS background fields to a supergravity multiplet, we verify that all solutions we find are half-supersymmetric. The two perturbative solutions we find both have an interpretation as the background geometry outside a string-like object. Correspondingly, we refer to these non-Lorentzian backgrounds as winding string and unwound string solution. Whereas the winding string is part of the on-shell spectrum of non-relativistic string theory, the unwound string only makes sense off-shell where it mediates the instantaneous gravitational force. Seen from the nine-dimensional point of view, we find that the winding string solution is sourced by a non-relativistic massive particle and that the unwound string solution is sourced by a massless Galilean particle of zero colour and spin. We explain how these two string solutions fit into a discrete lightcone quantization of string theory. We shortly discuss the basic NS five-brane and Kaluza-Klein monopole solutions and show that they are both half-supersymmetric.