Physics Letters B 767 (2017) 253–257
Contents lists available at ScienceDirect
Physics Letters B
www.elsevier.com/locate/physletb
Euclidean supergravity and multi-centered solutions
W.A. Sabra
Centre for Advanced Mathematical Sciences and Physics Department, American University of Beirut, Lebanon
a r t i c l e i n f o a b s t r a c t
Article history:
Received
21 January 2017
Accepted
27 January 2017
Available
online 2 February 2017
Editor:
M. Cveti
ˇ
c
In ungauged supergravity theories, the no-force condition for BPS states implies the existence of
stable static multi-centered solutions. The first solutions to Einstein–Maxwell theory with a positive
cosmological constant describing an arbitrary number of charged black holes were found by Kastor
and Traschen. Generalisations to five and higher dimensional theories were obtained by London.
Multi-centered solutions in gauged supergravity, even with time-dependence allowed, have yet to be
constructed. In this letter we construct supersymmetry-preserving multi-centered solutions for the case
of D = 5, N = 2Euclidean gauged supergravity coupled to an arbitrary number of vector multiplets.
Higher dimensional Einstein–Maxwell multi-centered solutions are also presented.
© 2017 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license
(http://creativecommons.org/licenses/by/4.0/). Funded by SCOAP
3
.
1. Introduction
In Newtonian gravity, one can obtain a system of point par-
ticles,
each having a charge equal to its mass, in static equilib-
rium
by balancing the mutual attractive gravitational and repul-
sive
electrostatic forces. In Einstein theory of general relativity and
quite surprisingly the analogous situation first appeared in the
early work of Weyl, Majumdar and Papapetrou [1]. The Majumdar–
Papapetrou
(MP) solutions were found to describe a system of
multi-centered extremal Reissner–Nordström black holes in ther-
mal
and mechanical equilibrium [2]. The MP metrics are the static
limits of the Israel–Wilson–Perjés (IWP) solutions [3]. If one con-
siders
Einstein–Maxwell theory as the bosonic sector of the theory
of N = 2, D = 4supergravity, then the MP metrics turn out to be
solutions admitting half of the supersymmetry [4]. Asystematic
classification by Tod [5] also demonstrated that the IWP metrics
are the unique solutions with time-like Killing vector admitting
supercovariantly constant spinors. Analogues of the MP solutions
were also found for black holes with a dilaton field in [6]. In [7]
general
half-supersymmetric solutions, which can be considered as
generalisation of the MP and IWP metrics, to the theories N = 2,
D = 4 supergravity with vector multiplets were found. BPS solu-
tions
in five-dimensional Einstein–Maxwell theory were considered
in [8]. The metric in this case is of the Tanghelini form [9]. More-
over,
electric and magnetic BPS solutions breaking half of the su-
persymmetry
in ungauged five-dimensional supergravity coupled
to vector multiplets were constructed in [10].
E-mail address: ws00@aub.edu.lb.
The first multi-centered solutions asymptotic to de Sitter space
were obtained in four dimensions in [11]. These are non-static
solutions to the Einstein–Maxwell equations in the presence of a
positive cosmological constant. They describe an arbitrary number
of charged black holes in motion due to the positive cosmologi-
cal
constant. As should be expected, these solutions reduce to MP
solutions in the limit of vanishing cosmological constant. Multi-
centered
solutions to d-dimensional Einstein–Maxwell theory with
a positive cosmological constant were given in [12]. In the five-
dimensional
case and with an imaginary coupling g (with the
cosmological constant being proportional to −g
2
), this theory may
be viewed as the bosonic sector of pure de Sitter D = 5, N = 2su-
pergravity.
Within this fake supergravity framework, it was shown
in [12] that the multi-centered solutions preserve some super-
symmetry
through the explicit construction of the corresponding
Killing spinors. Multi-centered solutions to D = 5, N = 2gauged
supergravity coupled to an arbitrary number of vector multiplets
were considered in [13,14]. In the fake de Sitter supergravity case,
one obtains rotating multi-centered solutions. However, in the
standard Anti-de Sitter cases, the multi-centered solutions have a
complex space–time metric.
In
this letter, we will be mainly concerned with the gauged ver-
sion
of the five-dimensional Euclidean supergravity theory which
was recently constructed in [15]. It will be demonstrated through
the analysis of the Killing spinor equations that this theory ad-
mits
multi-centered solutions with real space–time metric and real
fields unlike in the Lorentzian theory where the solution is com-
plex.
The results obtained may be useful as many investigations of
the AdS/CFT conjecture [16] have in fact been performed in Eu-
clidean
space.
http://dx.doi.org/10.1016/j.physletb.2017.01.067
0370-2693/
© 2017 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). Funded by
SCOAP
3
.