The AdS/CFT/Unparticle
Correspondence
Giacomo Caccipaglia, Guido MarandellaJamison Galloway, John McRaven
and work in progress David Stancato
hep-ph/0708.0005, 0804.0424, 0805.0799
Outline
unmotivation
IR cutoff
AdS/CFT/unparticle correspondence
gauge interactions
LHC applications
Hierarchy Problem Now
SUSY Technicolor
Hierarchy Problem Now
Extra Dimensions
SUSY Technicolor
flat curved
Hierarchy Problem Now
Extra Dimensions
SUSY Technicolor
flat curved
Hierarchy Problem Now
Extra Dimensions
SUSY Technicolor
HiggslessRSsmall
large
discrete
Little Higgs
MCH
gaugephobic
flat curved
Hierarchy Problem Now
Extra Dimensions
SUSY Technicolor
HiggslessRSsmall
large
discrete
Little Higgs
MCH
gaugephobicAll of these are fine-tuned!
Looking Under the Lamppost
Looking Under the Lamppost
quirks/hidden valleys/unparticles
New Sector
SM New
Mediator
Quirk/Hidden Valley/Unparticle Model
X
CFT, no confinement unparticles
QCD-like confinement hidden valley
stringy confinement quirks n=0
n=few
n=many
X is a heavy fermion with both SM and New gauge couplings
n fermionsNewSM
UnparticlesGeorgi:
a different way to calculate in CFT’s
phase space looks like a fractional number of particles
Georgi hep-ph/0703260, 0704.2457
!(p, d) !!
d4x eipx"0|TO(x)O†(0)|0#
=Ad
2!
! !
0(M2)d"2 i
p2 $M2 + i"dM2
Ad =16!5/2
(2!)2d
!(d + 1/2)!(d! 1)!(2d)
= iAd
2
!!p2 ! i!
"d!2
sin d"
unparticle propagator
d!(p, d) = Ad !!p0
"!!p2
" !p2
"d!2
d!(p, 1) = 2! "!p0
"#(p2)
unparticle phase space
p22 = 0
p2 = (p1 + p2)2 != 0
p21 = 0
p2i = 0
p2 =
!"
i
pi
#2
!= 0
CFT 101
discuss, this can have a profound impact on their mo-mentum dependence.
The spectral density !(p2, µ) defined in (7) obeys therenormalization-group evolution equation [50]
d!(p2, µ)
d lnµ= !
!2!cusp(µ) ln
p2
µ2+ 2"J(µ)
"!(p2, µ)
! 2!cusp(µ)
# p2
0
dp!2!(p!2, µ) ! !(p2, µ)
p2 ! p!2. (8)
The quantities !cusp and "J are anomalous dimensions,which depend on the renormalization scale only throughthe running coupling #s(µ). Their perturbative expan-sions are known to three-loop order. In particular, !cusp
is the cusp anomalous dimension of Wilson loops withlight-like segments [56], which plays a central role in thephysics of soft-gluon interactions (see e.g. [57]). We stressthat the form of the evolution kernel in (8) is exact; itssimplicity is a consequence of dimensonal analysis com-bined with some magic properties of Wilson lines.
The exact solution to the evolution equation was ob-tained in [54]. It can be written in the form
!(p2, µ0) = N(M, µ0)$p2
%!"1
" &j'
lnp2
M2+ $!, M
( e""E!
!(%), (9)
where $! denotes a derivative with respect to the quantity%, which is then identified with
% =
# M2
µ20
d&2
&2!cusp(&) . (10)
The normalization factor N has scaling dimension !2%and is given by
lnN(M, µ0) =
# M2
µ20
d&2
&2
!!cusp(&) ln
1
&2+ "J(&)
". (11)
This quantity is momentum-independent and will thusbe irrelevant to our discussion. The function &j(x, M) hasa perturbative expansion free of large logarithms. It isobtained from the Laplace transform
&j(x, M) =
# #
0
dp2 e"p2/s !(p2, M) , (12)
where s = ex+"EM2. At one-loop order [58]
&j(x, M) = 1 +CF #s(M)
4'
)2x2 ! 3x + 7 !
2'2
3
*. (13)
The two-loop expression for this function can be foundin [50].
When the tree-level approximation &j = 1 is used in(9), the result exactly coincides with the unparticle spec-tral density (2). The terms of order #s(M) in &j lead to
0 20 40 60 80 1000
0.05
0.1
0.15
0.2
0.25
0.3
p2 [GeV2]
!(p2
)/N
[GeV
!1]
1 2 5 10 20 50 100
0.05
0.1
0.2
0.5
p2 [GeV2]!(
p2)/
N[G
eV!
1]
FIG. 1. Comparison of the unparticle spectral density (2)(dashed) and the spectral density (9) of a massless quark jetat next-to-leading order in QCD (solid). We use parametersM = 10 GeV and ! = 0.5. The right plot shows the sameresults on logarithmic scales.
logarithmic modifications of the simple power form. Inthe “unparticle language” they would indicate a smallbreaking of conformal invariance, which is unavoidable ifthe unparticle sector is coupled to the Standard Model.Therefore, our result (9) shares all features of a realisticmodel for the spectral function of the unparticles of aconformal sector coupled to the Standard Model. In Fig-ure 1 we compare the results (2) and (9) for a particularset of input parameters.
In our “interacting particle model” for unparticlestates the exponent % = dU ! 1 is expressed as an in-tegral over the cusp anomalous dimension, see (10). In atheory such as QCD the numerical value of % can be O(1)provided the scales µ0 and M are widely separated. Thisis because the perturbative smallness of the cusp anoma-lous dimension is overcome by the logarithmic integra-tion over scales. In leading logarithmic approximationone finds
% #!0
(0ln
#s(µ0)
#s(M)(14)
with !0 = 4CF = 16/3 and (0 = 113
CA! 23nf = 23/3 (for
nf = 5 light flavors). Considering the case M = 10GeVas an example, we obtain % = 0.5 for µ # 1.2GeV. Otherexamples of jet functions have a similar functional formbut di"erent values of %. For the example of a gluon jetthe one-loop coe#cient !0 = 4CA is a factor 9/4 largerthan in the case of a quark jet (for Nc = 3), leading toeven larger % values.
The discussion above may be generalized to the case ofmassive QCD jets. If the quark field ) in (5) has mass m,then relations (5)–(8) remain valid, but the solution (9)must be modified. In this case it is no longer possible towrite the solution in closed form, however a perturbativeexpansion of the resummed spectral function can still beobtained [59,60]. At one-loop order one finds
3
Quarks are Unparticles
Neubert hep-ph/0708.0036
Why (broken) CFT’sare Interesting
unparticles must be equivalent to RS2
IR cutoff at TeV turns RS2 to RS1
a new type of IR cutoff could lead to new approaches to the hierarchy problem
new phenomenology for LHC
!(p, µ, d) !!
d4x eipx"0|TO(x)O†(0)|0#|µ
=Ad
2!
! !
µ2(M2 $ µ2)d"2 i
p2 $M2 + i"dM2
= iAd
2
!µ2 ! p2 ! i!
"d!2
sin d"
!(p, µ, 1) =i
p2 ! µ2 + i!
IR cutoff propagator
Fox, Rajaraman, Shirman hep-ph/0705.3092
M
!
!(p) ! (µ2 " p2 " i!)d!2
Spectral DensitiesRS1Unparticle/RS2
M
!
Massive Unparticle
M
!
ds2 =R2
z2
!dx2
µ ! dz2"
z > !
Sbulk =12
!d4x dz
!g(g!"!!"!"" + m2"2)
d[O] = 2± ! = 2±!
4 + m2R2
AdS/CFT
!(p, z) = az2J!(pz) + bz2J!!(pz)
!(p, ") = "!!R!3/2 !0(p)
d = 2± !
S =12
!d4p
(2!)4"0(!p)"0(p)K(p)
K(p) = (2! !)"!2! + b p2! + c p2"2!2! + . . .
S =12
!d4x dz !z
"R3
z3"!z"
#
AdS/CFT
d = 2! !
A
!0
S! =12
!d4p
(2!)4A(!p) K"1A(p)
S! =12
!d4p
(2!)4"0(!p)K"0(p) +
12
!d4p
(2!)4"0(p)A(p)
AdS/CFT
Klebanov, Witten hep-th/9905104
is the fieldis the source
d = 2! !
S! =12
!d4p
(2!)4A(!p) K"1A(p)
S! =12
!d4p
(2!)4"0(!p)K"0(p) +
12
!d4p
(2!)4"0(p)A(p)
AdS/CFT
!O(p!)O(p)" # !2S!
!A(p!) !A(p)# !(4)(p + p!)
(2")4(p2)d"2
Klebanov, Witten hep-th/9905104
z5!z
!1z3
!z"
"! z2(p2 ! µ2)"!m2R2" = 0
H = µz2
Sint =12
!d4x dz
!gH!!
!O(p!)O(p)" # !(4)(p + p!)(2")4
(p2 $ µ2)d"2
AdS/CFT/UnparticlesIR Cutoff
TMNbrane ! |gMN!|
!zIR
R
"2 µ4
R6z5IR !
!zIR
R
"224
M3!
R2
zIR ! 1µ
!24 R4µM3
!"1/5
M! = 1019 GeV, R"1 = 109 GeV, µ = 100GeV
1zIR! 10!23 GeV
IR Cutoff Stability
!F (p, m, d) !!
d4x eipx"0|T#(x)#†(0)|0$
= iAd!1/2
2!
! "
m2(M2 %m2)d!5/2 & p + m
p2 %M2 + i"dM2
= iAd!1/2
2 cos(d!)(& p + m)
"m2 % p2 % i"
#d!5/2
!F (p,m, 3/2) =i(! p + m)
p2 "m2 + i!
Unfermion propagator
Sbulk,f =!
d5x
"R
z
#4 $!i!̄"̄µ#µ!! i$"µ#µ$̄
+12($"##z !! !̄
"##z $̄) +
c
z
%$! + !̄$̄
&#
! = g(pz)!4
"̄ = f(pz)"̄4
g(pz) = z52
!A(p)Jc+ 1
2(pz) + B(p)J!c! 1
2(pz)
"
f(pz) = z52
!A(p)Jc! 1
2(pz) + B(p)J!c+ 1
2(pz)
"
AdS/CFT/Unfermions
!(p, ") = 0, #(p, ") = #0(p)
!!L(p!)!L(p)" # !(4)(p + p!)(2")4
i#µpµ(p2)d"5/2
S! =!
d4p
(2!)4"̄0
"i#̄µpµ(p2)3/2"d
#"0
S =!
d4p
(2!)4"0
"i#µpµ(p2)d!5/2
#"̄0
c <12 dL = 2! c
AdS/CFT/Unfermions
AdS/CFT/Unfermions
Cacciapaglia, Marandella, JT hep-th/0802.2946
c < !12
c <12
c >12
c > !12
dR =32
dL = 2! c
dL =32
dR = 2 + c
H = m z
cL = !cR
p!!
p2 "m2
Sint =!
d4x dz
"R
z
#5
H (!L"R + !R"L + h.c.)
AdS/CFT/Unfermions
S =!
d4p
(2!)4"†(p)
"µ2 ! p2
#2!d"(p)
F (x! y) =!!2 ! µ2
"2!d"(x! y)
Effective Action
S =!
d4xd4y !†(x)F (x! y)!(y)
F (x! y)" F (x! y)W (x, y)
Minimal Gauge Coupling
W (x, y) = P exp!!igT a
" y
xAa
µdwµ
#
...
cf Mandelstam Ann Phys 19 (1962) 1
= !igT a 2p! + q!
2p · q + q2
!"µ2 ! (p + q)2
#2!d !"µ2 ! p2
#2!d$
Gauge Vertex
! 14g2
5
! !
!d4x dz
"R
z
#!(z)F aMNF a
MN
!(z) = e!mz
1g24
=R
g25
! !
!
e"mz
z! R
g25
["!E " log(m")]
1g24
! R
g25
log!
!UV
m
"
AdS Gauge Fields
dilaton:
f !!(z)!!
m +1z
"f !(z) + p2f(z) = 0
zIR = 100/m zIR = 200/m
Gauge KK Modes
0.2 0.4 0.6 0.8 1.0 1.2 p!m
!1.0
!0.5
0.5
1.0
0.2 0.4 0.6 0.8 1.0 1.2 p!m
!1.0
!0.5
0.5
1.0
spectrum
unFermion Anomaliesp
p ! k2
p ! q
!!
!µ
!"!5
k1
k2q
p
p ! q
!!!5
!µ
!"
p ! k1
q
k1
k2
p
k1p ! q
!µ!
k2!"!5q
q k1
p
!!µ!5p ! k2
!"
k2
q
p
k1
!µ
p ! k1 k2
!!"!5
p
k1
k2
q
!!µ"!5
Galloway, McRaven, JT hep-th/0805.079
independent of d
unquark production
!d
!1
!!!!diag. 1
=d(2! d)2(4! d)
3
!d
!1
!!!!diag. 2
=(d! 1)(d! 2)(d2 ! 5d + 3)
3
!d(m) = (2! d)
!"
1! 4m2
q2
#3
!1(m = 0)
unquark production
d < 2
!unparticle = (2! d)!particle
Colored Unproduction
d < 2
R-Hadrons, anomalous jets/E loss
Cacciapaglia, Marandella, JT hep-ph/0708.0005
2 jets +
Pair production
is aligned to visible
!pT
!pT
CFT stuff radiationnot aligned!pT
pT
Anomalous Jets
QCD radiation
Hard jet + 2 jets +
in opposite direction to the hard jet
!pT
!pT
Detailed calculation and simulation needed (background)
Anomalous Jets
S = !!
d4x H†(!2 + µ2)2!dH
unHiggs Model
unHiggs Model
S = !!
d4x H†(D2 + µ2)2!dH + !ttRH
!d!1
"tb
#
L
+ h.c.
H =1!2eiT a!a/vd
!0
vd + h
"
!!
d4x !
"H†H
!2d!2! V 2
2
#2
unHiggs Model
S = !!
d4x H†(D2 + µ2)2!dH + !ttRH
!d!1
"tb
#
L
+ h.c.
m2h !
!4!2d
16!2
LY = !t tRH
!d!1
!tb
"
L
m2h = 3
!!t
!d!1
"2 !2
16"2= 3
#mt
V
$2 !4!2d
16"2
Mass Divergence
Solve the little hierarchy problem?
!g2Aa!Ab
""H†#T aT b"H#!
g!"(d ! 2)µ2!2d
!q!q"
q2
"(d ! 2)µ2!2d !
#µ2 ! q2
$2!d !#µ2
$2!d
q2
%&
M2W =
g2(2! d)µ2!2dv2d
4
unHiggs and MW
Mh ! "ig4
4M2W (2" d)µ2!2d
("s)2!d
WW Scattering
unHiggs exchange is insufficient to unitarize WW scattering
at large s
Mhh = !ig2
4M2W
!s +
(!s)2!d
(2! d)µ2!2d
"
WW Scattering
unHiggs 6 point vertex does unitarize WW scattering
!2 ! "(e+e! " HZ)"SM
unHiggs at LEP
1 1.2 1.4 1.6 1.8
d
0.1
0.2
0.3
0.4
0.5
0.6
!2MUnH " 50 GeV
MUnH " 100 GeV
10-2
10-1
1
20 40 60 80 100 120
mH
(GeV/c2)
95%
CL
lim
it o
n !
2
LEP"s = 91-210 GeV
Observed
Expected for background
(a)
a light unHiggs could have been missed at LEP
Conclusionsmassive unparticles with gauge interactions
are a new type of BSM physics
there are new kinds of LHC signals andnew ways to break electroweak symmetry
d!(p, µ, d) = Ad !!p0
"!!p2 ! µ2
" !p2 ! µ2
"d!2
d!(p, µ, 1) = 2! "!p0
"#(p2 ! µ2)
Massive Unparticle phase space
ig!a!(p, q) ! 2p! + q!
2p · q + q2
!"µ2 " (p + q)2
#2!d ""µ2 " p2
#2!d$
iqµ!aµ = "!1(p + q, m, d)T a ! T a"!1(p, m, d)
Ward-Takahashi Identity
unquark production
unquark production
divergent!
qq production: 1 loop
qq production: 1 loop
qq production: 1 loop
divergent!
qq production: 1 loop
qq production: 1 loop
divergent!
finite cross-section
+
unquark production
unquark production
Im!q2 ln(!q2/!2)
"= q2!
!d4p
(2!)4q2 ! 4p.q + 4p2
(q2 ! 2p.q)2
"2!
#(p! q)2
p2
$2!d
!#
p2
(p! q)2
$2!d%
unquark production
lnZ = !12
lnDet(D2 + m2)2!d
= !12Tr ln(D2 + m2)2!d
= !12(2! d)Tr ln(D2 + m2)
In General
!GB(q) = ! i
(µ2 ! q2 ! i!)2!d ! µ4!2d
!ab!"(q) = !g2"H†#T aT b"H# q!q"
q4
$!"
µ2 ! q2#2!d !
"µ2
#2!d$2
"GB(q)
unHiggs!
gauge invariance maintained
!
g!!H†"Aa
!T a!#!†Aa!T a!H"
"
$#!
µ2 # q2"2!d #
!µ2
"2!d$q!/q2
unHiggs