Physics Letters B 771 (2017) 401–407
Contents lists available at ScienceDirect
Physics Letters B
www.elsevier.com/locate/physletb
N = 4 l-conformal Galilei superalgebra
Anton Galajinsky
∗
, Ivan Masterov
Laboratory of Mathematical Physics, Tomsk Polytechnic University, 634050 Tomsk, Lenin Ave. 30, Russian Federation
a r t i c l e i n f o a b s t r a c t
Article history:
Received
11 May 2017
Received
in revised form 24 May 2017
Accepted
25 May 2017
Available
online 1 June 2017
Editor:
M. Cveti
ˇ
c
Keywords:
l-conformal
Galilei algebra
N
= 4 supersymmetry
An N = 4 supersymmetric extension of the l-conformal Galilei algebra is constructed. This is achieved by
combining generators of spatial symmetries from the l-conformal Galilei algebra and those underlying
the most general superconformal group in one dimension D(2, 1; α). The value of the group parameter α
is fixed from the requirement that the resulting superalgebra is finite-dimensional. The analysis reveals
α =−
1
2
thus reducing D(2, 1; α) to OSp(4|2).
© 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
There are at least two reasons to be concerned about N = 4 supersymmetric extensions of the l-conformal Galilei algebra [1,2]. On the
one hand, recently there has been extensive investigation of N = 4 superconformal many-body mechanics in one dimension aimed at a
microscopic description of the near horizon extreme Reissner–Nordström black hole (for a review and further references see [3]). In that
context, nonrelativistic superconformal algebras provide a natural framework for higher-dimensional generalizations [4]. At present, N = 4
is
regarded to be the maximum value for which the construction of interacting many-body models in d > 1is feasible. On the other hand,
the study of the nonrelativistic version of the AdS/CFT-correspondence has sparked substantial interest in nonrelativistic superconformal
symmetries and their realizations in field theory and mechanics.
1
Focusing on d = 1, N = 4 superconformal many-body mechanics based on the supergroup SU(1, 1|2), which is the instance relevant
for a microscopic description of the near horizon extreme Reissner–Nordström black hole [3], one reveals two prepotentials which govern
its dynamics [11]. They obey a coupled set of partial differential equations which are incompatible with translation invariance. Because
going beyond one dimension implies enforcing spatial translation symmetry, the construction of interacting d > 1, N = 4 superconformal
many-body mechanics based upon SU(1, 1|2) seems unfeasible.
The most general N = 4 supersymmetric extension of the conformal group in one dimension is given by the exceptional supergroup
D(2, 1; α) which is parametrized by a real number α. Its generators are associated with time translations, dilatations, special conformal
transformations, supersymmetry transformations and their superconformal partners, as well as with two variants of su(2)-transformations.
For α,
1
α
, −1 − α, and −
α
1+α
the associated Lie superalgebras are isomorphic [12]. As was demonstrated in [13], the master equations
which underlie D(2, 1; α) superconformal many-body mechanics admit translation invariant solutions provided α =−
1
2
. This hints at the
possibility to built an N = 4 supersymmetric extension of the l-conformal Galilei algebra based upon D(2, 1; −
1
2
) OSp(4|2).
The goal of this work is to formulate the structure relations of an N = 4 l-conformal Galilei superalgebra based upon osp(4|2) super-
algebra.
This is achieved by adding operators which generate spatial symmetries, including accelerations, to the superconformal algebra
osp(4|2) and finding a chain of extra bosonic and fermionic generators which are needed in order to close the full superalgebra.
The
work is organized as follows. In the next section we construct a representation of the Lie superalgebra associated with the su-
perconformal
group D(2, 1; α) in terms of differential operators in a superspace parametrized by one temporal and d spatial coordinates
along with four real fermions. In Sect. 3 we extend this superalgebra by spatial symmetry transformations which underlie the l-conformal
*
Corresponding author.
E-mail
addresses: galajin@tpu.ru (A. Galajinsky), masterov@tpu.ru (I. Masterov).
1
Literature on the subject is rather extensive. For a discussion relevant for this work see [5]. Some important earlier developments include [6–10].
http://dx.doi.org/10.1016/j.physletb.2017.05.086
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
.