Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Open exceptional strings and D-branes   We study D-branes in the extended geometry appearing in exceptional field
theory (or exceptional generalised geometry). Starting from the exceptional
sigma model (an $E_{d(d)}$ covariant worldsheet action with extra target space
coordinates), we define open string boundary conditions. We write down Neumann
and Dirichlet projectors compatible with the preservation of half-maximal
supersymmetry by the brane (building on previous work on the definition of
generalised orientifold quotients in exceptional field theory). This leads to a
definition of D-branes, plus their S-duals, as particular subspaces of the
exceptional geometry, and provides an opportunity to study D-branes in U-fold
backgrounds.

5
The categories of this paper are: gr-qc
10
The categories of this paper are: q-bio
3
The categories of this paper are: physics
35
The categories of this paper are: mtrl-th
36
The categories of this paper are: cmp-lg
22
The categories of this paper are: chao-dyn
26
The categories of this paper are: bayes-an
6
The categories of this paper are: astro-ph
25
The categories of this paper are: patt-sol
31
The categories of this paper are: ao-sci
19
The categories of this paper are: eess
37
The categories of this paper are: supr-con
28
The categories of this paper are: alg-geom
15
The categories of this paper are: nucl-ex
23
The categories of this paper are: solv-int
2
The categories of this paper are: math