Physics Letters B 791 (2019) 385–389
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Physics Letters B
www.elsevier.com/locate/physletb
Extended supersymmetric Calogero model
Sergey Krivonos
a
, Olaf Lechtenfeld
b,c,∗
, Alexander Provorov
a,d
, Anton Sutulin
a
a
Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, 141980 Dubna, Russia
b
Institut für Theoretische Physik, Leibniz Universität Hannover, Appelstrasse 2, 30167 Hannover, Germany
c
Riemann Center for Geometry and Physics, Leibniz Universität Hannover, Appelstrasse 2, 30167 Hannover, Germany
d
Moscow Institute of Physics and Technology (State University), Institutskii per. 9, Dolgoprudny, 141701 Russia
a r t i c l e i n f o a b s t r a c t
Article history:
Received
29 December 2018
Received
in revised form 28 February 2019
Accepted
4 March 2019
Available
online 7 March 2019
Editor:
M. Cveti
ˇ
c
Keywords:
Calogero
models
Extended
supersymmetry
We present a surprising redefinition of matrix fermions which brings the supercharges of the N -extended
supersymmetric A
n−1
Calogero model introduced in [1]to the standard form maximally cubic in the
fermions. The complexity of the model is transferred to a non-canonical and nonlinear conjugation prop-
erty
of the fermions. Employing the new cubic supercharges, we apply a supersymmetric generalization
of a “folding” procedure for A
2n−1
⊕ A
1
to explicitly construct the supercharges and Hamiltonian for arbi-
trary
even-N supersymmetric extensions of the B
n
, C
n
and D
n
rational Calogero models. We demonstrate
that all considered models possess a dynamical osp(N |2) superconformal symmetry.
© 2019 The Authors. 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
The A
n−1
Calogero Hamiltonian [2], describing one-dimensional
particles with inverse-square pairwise interactions,
H =
1
2
n
i
p
2
i
+
1
2
n
i=j
g
2
(x
i
− x
j
)
2
, (1.1)
plays a significant role in mathematical and theoretical physics. Be-
ing
the prime example of an integrable and solvable many-body
system, it appears in many areas of modern mathematical physics,
from high-energy to condensed-matter physics (see e.g. the re-
view [3] and
refs. therein). An intriguing hypothesis suggests that
the large-n limit of an n-particle N = 4 superconformal rational
Calogero model provides a microscopic description of the extremal
Reissner-Nordström black hole in the near-horizon limit [4]. Since
then, the task of constructing an (at least) N = 4 supersymmet-
ric
n-particle rational Calogero model has been the subject of
a number of papers [5–14], however with only partial success.
Despite the simplicity of the Hamiltonian (1.1), all attempts to
find an N =4 supersymmetric version beyond the four-particle
*
Corresponding author.
E-mail
addresses: krivonos@theor.jinr.ru (S. Krivonos),
lechtenf@itp.uni-hannover.de (O. Lechtenfeld), aleksanderprovorov@gmail.com
(A. Provorov),
sutulin@theor.jinr.ru (A. Sutulin).
case were unsuccessful. In contrast, the N = 2 supersymmetric
Calogero model has been found many years ago [15,16].
The
first attempt to construct an N = 4 supersymmetric ex-
tension
was performed by Wyllard [6]with a discouraging result.
Indeed, it was argued that such a system does not exist at all. The
next important step was taken in [9,10] where the supercharges
and Hamiltonian were explicitly constructed for the N = 4super-
symmetric
three-particle Calogero model. It was also shown that
Wyllard’s obstruction can be interpreted as a quantum correction,
so in the classical limit the Hamiltonian (1.1) could be obtained.
Unfortunately, beyond three particles the component description in
the Hamiltonian formalism of [9,10]leads to a system of nonlinear
equations for which even a proof of existence of solutions is rather
nontrivial. Specifically, enlarging the conformal algebra to the su-
persymmetric
case imposes severe constraints on the interactions,
which are not easily solved. Firstly, there is a nonzero prepoten-
tial
F which must obey a system of quadratic homogeneous dif-
ferential
equation of third order known as the Witten–Dijkgraaf–
Verlinde–Verlinde
(WDVV) equations [17,18]. The general solution
to the WDVV equations is unknown, but various classes based on
(deformed) Coxeter root systems have been found (see e.g. [19]).
Secondly, another prepotential U is subject to a system of linear
homogeneous differential equations of second order in a given F
background.
For known F solutions and without adding harmonic
spin variables, a nonzero U has been found for only up to three
particles, where the WDVV equations are still empty. A detailed
discussion of the supersymmetrization of Calogero models can be
found in the review [20].
https://doi.org/10.1016/j.physletb.2019.03.004
0370-2693/
© 2019 The Authors. 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
.