A covariantisation of M5-brane action in dual formulation

We construct a manifestly diffeomorphic M5-brane action in dual formulation coupled to an eleven-dimensional supergravity target space. The covariantisation is carried out by using (generalised) PST technique with 5 auxiliary scalar fields, which are obtained by using a geometrical consideration as a reduction of an auxiliary 4-form of Maznytsia-Preitschopf-Sorokin. As is typical in PST-covariantised theory, our construction possesses as usual the two local PST symmetries. By using one of the local PST symmetries, the action can be reduced to the non-manifestly covariant M5-brane action in dual formulation constructed earlier by the authors. The discussion on double dimensional reduction to D4-brane, and on the comparison of on-shell action then easily follows.Comment: 26 page

Chiral 2-form actions and their applications to M5-brane(s)

We study the symmetry and dynamics of M5-branes as well as chiral p-forms in this thesis. In the first part, we propose a model describing the gauge sector of multiple M5-branes. The model has modified six-dimensional Lorentz symmetry and its double dimensional reduction gives 5D Yang-Mills theory with higher derivative corrections. The non-abelian self-dual string solutions to this model are presented. In the second part of the thesis, we propose an alternative new action for the single M5-brane. The six-dimentional worldvolume space is covariantly split into 3+3. The relation of the new action to the conventional PST action as well as to the M2- brane action are studied. Finally, we briefly discuss the attempt to formulate the M5-brane action in a 2+4 splitting of worldvolume space and some duality properties and issues of chiral p-form actions

The M5-brane action revisited

We construct an alternative form of the M5-brane action in which the six-dimensional worldvolume is subject to a covariant split into 3+3 directions by a triplet of auxiliary fields. We consider the relation of this action to the original form of the M5-brane action and to a Nambu-Poisson 5-brane action based on the Bagger-Lambert-Gustavsson model with the gauge symmetry of volume preserving diffeomorphismsComment: 26 pages, v2: minor corrections, references added and update

Non-abelian Action for Multiple Five-Branes with Self-Dual Tensors

We construct an action for non-abelian 2-form in 6-dimensions. Our action consists of a non-abelian generalization of the abelian action of Perry and Schwarz for a single five-brane. It admits a self-duality equation on the field strength as the equation of motion. It has a modified 6d Lorentz symmetry. On dimensional reduction on a circle, our action gives the standard 5d Yang-Mills action plus higher order corrections. Based on these properties, we propose that our theory describes the gauge sector of multiple M5-branes in flat space.Comment: LaTeX, 26 pages. v2: improved discussion of Lorentz symmetry. ref added. v3: add comments in the discussion section on the inclusion of scalar fields and supersymmetry; title changed to a more suitable one; version published in JHE