没有合适的资源?快使用搜索试试~ 我知道了~
温馨提示
通过在谢赫·贾巴里(Sheikh-Jabbari)引入的微小引力子矩阵模型中将它们描述为瞬时子,我们在AdS 5×S 5的IIB型弦理论中研究了具有角动量N 1/2≪ J≪ N的巨型引子的分裂和结合相互作用。 在大J时,瞬时子方程可以映射到四维Laplace方程,并且在n个薄片的Riemann空间中m个点电荷的库仑电势对应于巨型引子的m对n相互作用过程。 这些瞬时子提供所有半重算子的全息对偶,并且瞬时子振幅与Schur多项式相关器在N $$ \ mathcal {N} $$ = 4 SYM中由Corley,Jevicki和 Ramgoolam。
资源推荐
资源详情
资源评论
JHEP05(2018)065
Published for SISSA by Springer
Received: March 14, 2018
Accepted: May 1, 2018
Published: May 9, 2018
Giant graviton interactions and M2-branes ending on
multiple M5-branes
Shinji Hirano
a,b
and Yuki Sato
c
a
School of Physics and Mandelstam Institute for Theoretical Physics &
DST-NRF Centre of Excellence in Mathematical and Statistical Sciences (CoE-MaSS),
University of the Witwatersrand,
1 Jan Smuts Avenue, Johannesburg, South Africa
b
Center for Gravitational Physics, Yukawa Institute for Theoretical Physics, Kyoto University,
Kitashirakawa-Oiwakecho, Kyoto 606-8502, Japan
c
Department of Physics, Faculty of Science, Chulalongkorn University,
Thanon Phayathai, Pathumwan, Bangkok 10330, Thailand
E-mail: shinji.hirano@wits.ac.za, ysato.phys@gmail.com
Abstract: We study splitting and joining interactions of giant gravitons with angular
momenta N
1/2
J N in the type IIB string theory on AdS
5
× S
5
by describing them
as instantons in the tiny graviton matrix model introduced by Sheikh-Jabbari. At large J
the instanton equation can be mapped to the four-dimensional Laplace equation and the
Coulomb potential for m point charges in an n-sheeted Riemann space corresponds to the
m-to-n interaction process of giant gravitons. These instantons provide the holographic
dual of correlators of all semi-heavy operators and the instanton amplitudes exactly agree
with the pp-wave limit of Schur polynomial correlators in N = 4 SYM computed by Corley,
Jevicki and Ramgoolam.
By making a slight change of variables the same instanton equation is mathematically
transformed into the Basu-Harvey equation which describes the system of M2-branes ending
on M5-branes. As it turns out, the solutions to the sourceless Laplace equation on an n-
sheeted Riemann space correspond to n M5-branes connected by M2-branes and we find
general solutions representing M2-branes ending on multiple M5-branes. Among other
solutions, the n = 3 case describes an M2-branes junction ending on three M5-branes. The
effective theory on the moduli space of our solutions might shed light on the low energy
effective theory of multiple M5-branes.
Keywords: AdS-CFT Correspondence, D-branes, M(atrix) Theories, M-Theory
ArXiv ePrint: 1803.04172
Open Access,
c
The Authors.
Article funded by SCOAP
3
.
https://doi.org/10.1007/JHEP05(2018)065
JHEP05(2018)065
Contents
1 Introduction 1
2 IIB plane-wave matrix model 3
2.1 Vacua 7
2.2 Instanton equations 8
3 Four-dimensional Laplace equation in Riemann spaces 10
3.1 Hypertoroidal coordinates and Riemann spaces 13
3.2 Splitting interactions of giant gravitons 14
3.2.1 Coulomb potential in two-sheeted Riemann space 16
3.2.2 Coulomb potential in n-sheeted Riemann space 18
4 Giant graviton correlators in CFT 20
4.1 Three-point functions of sphere giants 20
4.2 General m-to-n functions of sphere giants 21
5 The Basu-Harvey equation 22
5.1 M2-branes stretched between two M5-branes — funnel solution 24
5.2 M2-branes ending on multiple M5-branes 25
6 Summary and discussions 26
A A derivation of the Laplace equation 29
B The Euclidean 3-brane theory 30
C Three-spheres and their quantisation 31
C.1 Fuzzy three-spheres 32
C.2 Fixing the quantisation parameter 33
1 Introduction
Giant gravitons are spherical branes moving fast along the great circle of the sphere in the
AdS
p
×S
q
geometry [1–3] and correspond to Schur polynomial operators in dual CFTs [4, 5].
They form an orthogonal basis for multi-graviton states with Kaluza-Klein (KK) momenta
and are appropriate objects for studying KK graviton interactions. In this paper we focus
on giant gravitons in the type IIB string theory on AdS
5
× S
5
which is dual to N = 4
U(N) SYM [6]. On the CFT side, their interactions correspond to multi-point correlators
of Schur polynomial operators and have been computed exactly for half-BPS giants in [5].
– 1 –
JHEP05(2018)065
However, on the gravity side, being extended objects (spherical D3-branes), it is rather
challenging to go beyond kinematics and study their dynamical interaction process except
for so-called heavy-heavy-light three point interactions. This is the problem we tackle in
the most part of this paper and we report modest but nontrivial progress on this issue.
Instead of attempting to solve the issue once and for all, we consider a certain subset of
giant gravitons, namely, those whose angular momentum J are relatively small, i.e. in the
range N
1/2
J N. These giants can be studied in the plane-wave background [7–9]: for
an observer moving fast in the sphere, the spacetime looks approximately like a plane-wave
geometry.
1
Thus if the size of giants is small enough,
2
the observer moving along with the
giants can study them in the plane-wave background [7–9].
This strategy was inspired by the recent work of one of the authors which studied split-
ting and joining interactions of membrane giants in the M-theory on AdS
4
×S
7
/Z
k
at finite
k by zooming into the plane-wave background [13, 14]. Since the M-theory on the plane-
wave background is described by the BMN plane-wave matrix model [7], small membrane
giants can be studied by this matrix quantum mechanics. Their idea is that since the vacua
of the BMN matrix model represent spherical membranes, instantons interpolating among
them correspond to the process of membrane interactions. They explicitly constructed
these instantons by mapping the BPS instanton equation [15] to Nahm’s equation [16, 17]
in the limit of large angular momenta where Nahm’s equation becomes equivalent to the 3d
Laplace equation [18, 19]. The crux of their construction is to consider the Laplace equa-
tion not in the ordinary 3d Euclidean space but in a 3d analog of 2d Riemann surfaces,
dubbed Riemann space [20].
In our case of the type IIB string theory on AdS
5
×S
5
, as it turns out, the most effec-
tive description of giant gravitons with the angular momentum N
1/2
J N is provided
by the tiny graviton matrix model proposed by Sheikh-Jabbari [21, 22] rather than BMN’s
type IIB string theory on the pp-wave background.
3
The description of giant graviton
interactions is similar to the above M-theory case, and in the large J limit the instanton
equation in this matrix quantum mechanics can be mapped to the Laplace equation but
in four dimensions instead of three. As we will see, the 4d Coulomb potential for m point
charges in an n-sheeted Riemann space corresponds to the m-to-n interaction process of gi-
ant gravitons. An advantage over the M-theory case is that we can compare our description
of giant graviton interactions to that of N = 4 SYM. Indeed, we find that the instanton
amplitude exactly agrees with the pp-wave limit of Schur polynomial correlators in N = 4
SYM computed by Corley, Jevicki and Ramgoolam [5]. This also implies that these instan-
tons successfully provide the holographic dual of correlators of all semi-heavy operators.
Last but not the least, as a byproduct of this study we are led to find new results
on elusive M5-branes. By a slight change of variables, the instanton equation of the type
IIB plane-wave matrix model is identical to the Basu-Harvey equation which describes the
system of M2-branes ending on M5-branes [23]. In the large J limit which corresponds, in
1
The plane-wave geometry can be obtained from AdS
p
× S
q
by taking the Penrose limit [10–12].
2
Small giants are an oxymoron. They are small in the sense that their size is much smaller than the
AdS radius, but they are not point-like and much larger than the Planck length.
3
In this paper we refer to the tiny graviton matrix model as the type IIB plane-wave matrix model.
– 2 –
JHEP05(2018)065
the Basu-Harvey context, to a large number of M2-branes, we find the solutions describing
M2-branes ending on multiple M5-branes, including the funnel solution [24, 25] and an
M2-branes junction connecting three M5-branes as simplest examples. The number n of
M5-branes corresponds to the number of sheets in the Riemann space, and somewhat sur-
prisingly, multiple M5-branes solutions are constructed from a trivial constant electrostatic
potential. Upon further generalisations, the effective theory on the moduli space of our
solutions might shed light on the low energy effective theory of multiple M5-branes [26–
28, 31–34].
This paper is organised as follows: in section 2, we review the IIB plane-wave matrix
model and its BPS vacua which contain concentric fuzzy three-spheres. We then discuss the
instanton equation and find the (anti-)instanton action for the m-to-n joining and splitting
process of giant gravitons. As the first check of our proposal we show that the instanton
amplitude e
−S
E
in the case of the 2-to-1 interaction agrees with the 3-point correlators of
antisymmetric Schur operators in the dual CFT, i.e. N = 4 SYM. In section 3, we transform
the instanton equation to the Basu-Harvey equation by a suitable change of variables and
show that in the large J limit it is further mapped locally to the 4d Laplace equation. We
then solve the 4d Laplace equation in multi-sheeted Riemann spaces and find the solutions
which describe the generic m-to-n joining and splitting process of (concentric) sphere giants.
In section 4, we discuss the pp-wave limit of correlators of antisymmetric Schur operators
in the dual CFT and show that they exactly agree with the instanton amplitudes obtained
in section 3. In section 5, we study the Basu-Harvey equation in the original context,
namely, as a description of the M2-M5 brane system. In the large J limit corresponding
to a large number of M2-branes, we find the solutions to the 4d Laplace equation which
describe M2-branes ending on multiple M5-branes. Section 6 is devoted to summary and
discussions. In the appendices A, B and C we elaborate further on some technical details.
2 IIB plane-wave matrix model
The tiny graviton matrix model was proposed by Sheikh-Jabbari as a candidate for the
discrete lightcone quantisation (DLCQ) of the type IIB string theory on the maximally su-
persymmetric ten-dimensional plane-wave background [21]. We refer to this matrix model
as the IIB plane-wave matrix model in this paper.
Here we outline the derivation of the IIB plane-wave matrix model. The bosonic part
of the IIB plane-wave matrix model can be obtained by a matrix regularisation of the
effective action for a 3-brane [21]:
S = −T
Z
dtd
3
σ
q
|det(h
µν
)| + C
ˆµˆν ˆρ
ˆ
λ
∂x
ˆµ
∂t
∂x
ˆν
∂σ
1
∂x
ˆρ
∂σ
2
∂x
ˆ
λ
∂σ
3
!
, (2.1)
where T = 1/((2π)
3
g
s
l
4
s
) is the D3-brane tension with g
s
and l
s
being the string coupling
constant and string length, respectively. The world-volume coordinates are σ
µ
= (t, σ
l
)
with µ = 0, 1, 2, 3 and l = 1, 2, 3. The indices for the target space are hatted, ˆµ, ˆν, ˆρ,
ˆ
λ =
+, −, 1, ··· , 8. The background metric is the plane-wave geometry:
g
ˆµˆν
dx
ˆµ
dx
ˆν
= −2dx
+
dx
−
− µ
2
(x
i
x
i
+ x
a
x
a
)dx
+
dx
+
+ dx
i
dx
i
+ dx
a
dx
a
, (2.2)
– 3 –
JHEP05(2018)065
with i = 1, 2, 3, 4 and a = 5, 6, 7, 8. The induced metric on the 3-brane is
h
µν
= g
ˆµˆν
∂
µ
x
ˆµ
∂
ν
x
ˆν
, (2.3)
and C
ˆµˆν ˆρˆσ
is the Ramond-Ramond 4-form with nonvanishing components
C
+ijk
= −µ
ijkl
x
l
, C
+abc
= −µ
abcd
x
d
. (2.4)
The parameter µ in (2.2) and (2.4) is the mass parameter.
In the lightcone gauge we fix x
+
= t while imposing h
0l
= 0 and choose the spatial
world-volume coordinates σ
l
such that the lightcone momentum density −p
−
is a constant.
The lightcone Hamiltonian for the 3-brane is then given by [21, 36]
−P
+
=
Z
d
3
σ
[σ]
2(−P
−
)
(p
I
)
2
+
µ
2
(−P
−
)
2[σ]
(x
I
)
2
+
T
2
[σ]
2 · 3!(−P
−
)
{x
I
, x
J
, x
K
}
2
−
µT
3!
ijkl
x
i
{x
j
, x
k
, x
l
} +
abcd
x
a
{x
b
, x
c
, x
d
}
, (2.5)
where I, J, K = 1, 2, ··· , 8 are transverse directions, x
I
= (x
i
, x
a
) and p
I
= (p
i
, p
a
) are the
conjugate momenta of x
I
. P
±
are the zero-modes of p
±
and the conjugate momenta of x
±
.
[σ] is the total volume in the σ-space defined as
[σ] =
Z
d
3
σ . (2.6)
The Nambu three-bracket in (2.5) is defined for real functions, f
p
(σ) with p = 1, 2, 3, as
{f
1
, f
2
, f
3
} =
lmn
∂f
1
∂σ
l
∂f
2
∂σ
m
∂f
3
∂σ
n
. (2.7)
Since the constraints, h
r0
= 0, can be recast as
∂x
−
∂σ
r
=
[σ]
(−p
−
)
p
I
∂x
I
∂σ
r
, (2.8)
the dynamics of x
−
can be determined by that of the transverse directions. The con-
straints (2.8) together with the conditions,
lmn
∂
∂σ
m
∂
∂σ
n
x
−
= 0, can be rewritten as
lmn
∂x
I
∂σ
m
∂p
I
∂σ
n
= 0 . (2.9)
This should correspond to the generator of the residual local symmetry analogous to the
area-preserving diffeomorphism of the membrane theory in the lightcone gauge.
We further compactify the x
−
in the background (2.2) on a circle of radius R, resulting
in the quantised total lightcone momentum:
− P
−
= −p
−
[σ] =
J
R
, (2.10)
where J is an integer.
– 4 –
剩余35页未读,继续阅读
资源评论
weixin_38625048
- 粉丝: 3
- 资源: 946
上传资源 快速赚钱
- 我的内容管理 展开
- 我的资源 快来上传第一个资源
- 我的收益 登录查看自己的收益
- 我的积分 登录查看自己的积分
- 我的C币 登录后查看C币余额
- 我的收藏
- 我的下载
- 下载帮助
最新资源
资源上传下载、课程学习等过程中有任何疑问或建议,欢迎提出宝贵意见哦~我们会及时处理!
点击此处反馈
安全验证
文档复制为VIP权益,开通VIP直接复制
信息提交成功