相关论文: On BPS preons, generalized holonomies and D=11 sup…
After introducing the notion of BPS preons as the basic constituents of M-theory, we discuss the recent negative results in the search for solutions of the D=10 and D=11 supergravity equations preserving 31/32 supersymmetries i.e., of…
In this PhD Thesis, supersymmetry and its formulation in the context of D=11 supergravity is discussed from several perspectives. The role of generalized holonomy as a classification tool of supersymmetric supergravity solutions is…
We consider the present absence of 31 out of 32 supersymmetric solutions in supergravity i.e., of solutions describing BPS preons. A recent result indicates that (bosonic) BPS preonic solutions do not exist in type IIB supergravity. We…
We review briefly the notion of BPS preons, first introduced in 11-dimensional context as hypothetical constituents of M-theory, in its generalization to arbitrary dimensions and emphasizing the relation with twistor approach. In…
Tensionless super-p-branes in a generalized superspace with additional tensorial central charge coordinates may provide an extended object model for BPS preons, i.e. for the hypothetical constituents of M-theory preserving 31 of 32…
We describe generalized D=11 Poincar\'{e} and conformal supersymmetries. The corresponding generalization of twistor and supertwistor framework is outlined with $OSp(1|64)$ superspinors describing BPS preons. The $\frac{k}{32}$ BPS states…
Supersymmetric solutions of 11-dimensional supergravity can be classified according to the holonomy of the supercovariant derivative arising in the Killing spinor condition. It is shown that the holonomy must be contained in $\SL(32,\R)$.…
We show that the holonomy of the supercovariant connection for M-theory backgrounds with $N$ Killing spinors reduces to a subgroup of $SL(32-N,\bR)\st (\oplus^N \bR^{32-N})$. We use this to give the necessary and sufficient conditions for a…
We deepen and refine the classification of supersymmetric solutions to N=2, D=4 gauged supergravity obtained in a previous paper. In the case where the Killing vector constructed from the Killing spinor is timelike, it is shown that the…
We present here the AdS generalization of BPS preons, which were introduced as the hypothetical constituents of M-theory preserving all but one supersymmetries. Our construction, suggested by the relation of `lower dimensional preons' with…
We briefly review here the notion of BPS preons, the hypothetical constituents of M-theory, emphasizing its generalization to arbitrary dimensions D and its relation to higher spin theories in D=4,6 and 10.
We show that eleven-dimensional supergravity backgrounds with thirty one supersymmetries, N=31, admit an additional Killing spinor and so they are locally isometric to maximally supersymmetric ones. This rules out the existence of simply…
We review the evidence for the various dualities amongst the five D=10 superstring theories and for the existence of M-theory using the associated effective supergravity theories. We also summarise the combinatorial technics developed for…
We provide a complete algebraic description of BPS states in M-theory in terms of primary constituents that we call BPS preons. We argue that any BPS state preserving $k$ of the 32 supersymmetries is a composite of (32-k) BPS preons. In…
We show that the holonomy of the supercovariant connection of IIB supergravity is contained in $SL(32, \bR)$. We also find that the holonomy reduces to a subgroup of $SL(32-N)\st (\oplus^N \bR^{32-N})$ for IIB supergravity backgrounds with…
We classify all supersymmetric solutions of minimal gauged supergravity in four dimensions. There are two classes of solutions that are distinguished by the norm of the Killing vector constructed from the Killing spinor. If the Killing…
In the main part of this thesis, we present the foundations and initial results of the Spinorial Geometry formalism for solving Killing spinor equations. This method can be used for any supergravity theory, although we largely focus on D=11…
We study supersymmetric AdS$_D$ backgrounds of eleven-dimensional or type II supergravity preserving $\mathcal{N}$ supersymmetries using generalised geometry. We show that a large class correspond precisely to spaces admitting a generalised…
We extend the refined G-structure classification of supersymmetric solutions of eleven dimensional supergravity. We derive necessary and sufficient conditions for the existence of an arbitrary number of Killing spinors whose common isotropy…
Supersymmetric backgrounds in M-theory often involve four-form flux in addition to pure geometry. In such cases, the classification of supersymmetric vacua involves the notion of generalized holonomy taking values in SL(32,R), the Clifford…