studying the operator bases of...
TRANSCRIPT
Studying the Operator Bases of EFTs
Xiaochuan Lu
UC Davis Joint Theory Seminar, Nov 30, 2015
Brian Henning, Tom Melia, Hitoshi Murayama
111/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
UC Davis
11/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis 2
Highlights
• Operator bases of EFTs are organized by the conformal algebra
• A completely automated technique is developed for counting the dimension of an operator basis
1 dimensional spacetime (arXiv: 1507.07240)General spacetime dimension (arXiv: 1601.xxxxx)Application to SM EFT (arXiv: 1512.xxxxx)……
The operator basis of an (non-conformal) EFT is spanned by the set of scalar (spin-0) conformal primaries formed from thecanonical fields and their derivatives
B. Henning, XL, T. Melia and H. Murayama:
11/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis 3
Highlights
1 generation
3 generations
SM EFT
B. Henning, XL, T. Melia and H. Murayama, arXiv: 1512.xxxxx
11/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis 4
Highlights
1 generation
3 generations
SM EFT
B. Henning, XL, T. Melia and H. Murayama, arXiv: 1512.xxxxx
11/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis 5
Highlights
1 generation
3 generations
SM EFT
B. Henning, XL, T. Melia and H. Murayama, arXiv: 1512.xxxxx
931 by L. Lehman and A. Martin (LM), arXiv: 1510.00372
Motivation
Why counting operators?
611/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
A theory field content symmetries imposed
{ }, , ,Aµφ ψ ( ) ( ) ( )Lorentz invar
3 2 1iance
c W YSU SU U×
×
SM
MSSM
19
105
Degree of freedom of the theory Practical use?
Motivation
Why counting operators?
711/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
A theory field content symmetries imposed
{ }, , ,Aµφ ψ
SM
MSSM
19
105
Degree of freedom of the theory Practical use? None…
( ) ( ) ( )Lorentz invar
3 2 1iance
c W YSU SU U×
×
Motivation
Why counting operators?
811/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
A theory field content symmetries imposed
{ }, , ,Aµφ ψ
SM
MSSM
19
105
Degree of freedom of the theory Practical use?
The technique developed maybe useful in studying deeper underlying structures, if any
None…
( ) ( ) ( )Lorentz invar
3 2 1iance
c W YSU SU U×
×
Motivation
911/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
The number is large!
What is hard about counting operators?
Motivation
1011/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
An operator basis: A set of complete but independent operators
What is hard about counting operators?
• Redundancy relations
- Equations of Motion (EOM)
- Integration by Part (IBP)
- Group Identities
• Complicated field content
• Various symmetries
{ }, , , , , , , ,a aH Q u d L e G W Bµν µν µνΦ∈
( ) ( ) ( ) , Lorentz invaria1 n e3 2 cc W Y
SU SU U× ×
( ) ( ) 2µµ αγ βδαβ γδ
σ σ =
2 0D φ× =
( ) 0Dµµ =
SM EFT: ( ) ( ) 5 2 7 46 3 81 1 1 1
SMΦ = Φ + + + +Λ Λ
+Λ Λ
Motivation
1111/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
What is hard about counting operators?
80 baryon conserving
• W. Buchmuller and D. Wyler, Nucl. Phys. B 268 (1986) 621
• B. Grzadkowski, M. Iskrzynski, M. Misiak, and J. Rosiek, arXiv: 1008.4884
• L. Lehman and A. Martin, arXiv: 1510.00372
59 baryon conserving
dim 6, 1fN= =
dim 8, 1fN= =
535 operators = 931 real coefficients
Motivation
1211/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
What is hard about counting operators?
80 baryon conserving
• W. Buchmuller and D. Wyler, Nucl. Phys. B 268 (1986) 621
• B. Grzadkowski, M. Iskrzynski, M. Misiak, and J. Rosiek, arXiv: 1008.4884
• L. Lehman and A. Martin, arXiv: 1510.00372
59 baryon conserving
dim 6, 1fN= =
dim 8, 1fN= =
535 operators = 931 real coefficients 993 real coefficients
Motivation
1311/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
What is hard about counting operators?
dim 6=
counting by hand…
B. Grzadkowski, M. Iskrzynski, M. Misiak, and J. Rosiek, arXiv: 1008.4884
Motivation
1411/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
Our goal: find a systematic, automated, and correct way of doing it
Motivation
1511/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
Our goal: find a systematic, automated, and correct way of doing it
Motivation
1611/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
Our goal: find a systematic, automated, and correct way of doing it
• Review of non-derivative techniques
Outline for the rest of this talk
• derivative warm up: 1d spacetime
• true task: higher d spacetime
1711/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
non-derivative techniques
Counting technique without derivative (Invariant theory)
1811/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
arXiv: 0907.4763, E. E. Jenkins and A. V. Manohar
Good reviews:
arXiv: 1010.3161, A. Hanany, E. E. Jenkins, A. V. Manohar, and G. Torri
arXiv: 1503.07537, L. Lehman and A. Martin
• Hilbert series as an organizing tool• Molien-Weyl formula
1911/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
Hilbert series as an organizing tool
[ ] { }211 1 22, , , ,nrr
n ir
nx x x x x x rV= ∈
1 2 , ?n rr r r cr+ + += =
polynomial ring Organizing all order information:
non-derivative techniques
( )0
, 1r
rrucH u u
=
∞
= <∑grading
counting information at each order
2011/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
Hilbert series as an organizing tool
[ ] ( )0
1, 1,1
, rr
r
x c u uu Hu
φ φ∞
=
= = = =→ =−∑
[ ] { }211 1 22, , , ,nrr
n ir
nx x x x x x rV= ∈
1 2 , ?n rr r r cr+ + += =
polynomial ring Organizing all order information:
non-derivative techniques
( )0
, 1r
rrucH u u
=
∞
= <∑grading
counting information at each order
2111/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
Hilbert series as an organizing tool
[ ] ( )0
1, 1,1
, rr
r
x c u uu Hu
φ φ∞
=
= = = =→ =−∑
[ ] { }211 1 22, , , ,nrr
n ir
nx x x x x x rV= ∈
1 2 , ?n rr r r cr+ + += =
polynomial ring
1 2
1 1 11 1 1 n
Hu u u
=− − −
[ ]1 2, ,, nφ φ φ= 1 2 nu u uu = = = =
( )1
1 nHu
=−
i i ix uφ= → multi-graded
Organizing all order information:
non-derivative techniques
( )0
, 1r
rrucH u u
=
∞
= <∑grading
counting information at each order
2211/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
Hilbert series as an organizing tool
[ ] ( )0
1, 1,1
, rr
r
x c u uu Hu
φ φ∞
=
= = = =→ =−∑
[ ] { }211 1 22, , , ,nrr
n ir
nx x x x x x rV= ∈
1 2 , ?n rr r r cr+ + += =
polynomial ring
freely generated
1 2
1 1 11 1 1 n
Hu u u
=− − −
[ ]1 2, ,, nφ φ φ= 1 2 nu u uu = = = =
( )1
1 nHu
=−
i i ix uφ= → multi-graded
Organizing all order information:
non-derivative techniques
( )0
, 1r
rrucH u u
=
∞
= <∑grading
counting information at each order
2311/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
Example for non freely generated ring
( )33
2 2 3 42, 1, , 1
1uu H uu uuuu
φ φ φ +→ = + + = + + + − =
−
non-derivative techniques
2411/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
Example for non freely generated ring
( )33
2 2 3 42, 1, , 1
1uu H uu uuuu
φ φ φ +→ = + + = + + + − =
−
non-derivative techniques
( )( ) ( )( )2 2
12 33 3
1 22
1 11 1 1 1
uuu
xH
x x uxφ
φ
⇒ = = − − −= → −
= → ?
2511/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
Example for non freely generated ring
( )33
2 2 3 42, 1, , 1
1uu H uu uuuu
φ φ φ +→ = + + = + + + − =
−
3 21 2x x= 3 2
1 2I x x= −redundancy relation
[ ] 3 21 2 1 2/ , /x xR I x x= = − A quotient ring
non-derivative techniques
( )( ) ( )( )2 2
12 33 3
1 22
1 11 1 1 1
uuu
xH
x x uxφ
φ
⇒ = = − − −= → −
= → ?
2611/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
Example for non freely generated ring
( )33
2 2 3 42, 1, , 1
1uu H uu uuuu
φ φ φ +→ = + + = + + + − =
−
3 21 2x x= 3 2
1 2I x x= −redundancy relation
[ ] 3 21 2 1 2/ , /x xR I x x= = − A quotient ring
non-derivative techniques
( )( ) ( )( )2 2
12 33 3
1 22
1 11 1 1 1
uuu
xH
x x uxφ
φ
⇒ = = − − −= → −
= → ?
( )( ) ( )( )31
6
2
3
2 321
1 1 11 1 11 1
u uHx x uu u
x − += = =
− −−
− −−
the least common multiple
2711/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
2
1 11 1x u
H =− −
=
( ) [ ],φ φ=
Imposing symmetries
*
1 11 1x u u
H =− −
=
* *
**
uu
ux uφ
φ
φ
φ →
→→=
( )* *,, ,φ φ φ φ =
[ ]inv x= [ ]inv x=
non-derivative techniques
2 2
ux uφ
φ
→=
→
{ }22
, ee PPP
Ze
φ φφ φ
=== −=
( )* *
1 ,i
i
eU
e
θ
θ
φ φ
φ φ−
→
→
2811/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
Nontrivial examples of imposing symmetries
( ) { }1 2 2
1 1 2 2
, , ,,
e PP
ZP
φ φφ φ φ φ
=
= − = −
2 21 1 2 2 3 1 2, ,x x xφ φ φφ= = =
21 2 3x x x=
[ ] 21 2 3 1 2 3, , /inv x x x x x x= −
( )( )( )
( )( )
1 2 3
1 22 21
1 2
2
11 1 1
11 1
Hx x x
uu
x
u
x
u
=− −
+=
− −
−−
( ) ( )* *1 1 2 2
21 1 2 2
, , , , 1
,i ie e
Uθ θ
φ φ φ φ
φ φ φ φ→ →
* 2 * *21 1 1 2 2 2 3 1 2 4 1
*2, , ,x x x xφφ φ φ φ φ φ φ= = = =
21 2 3 4x x x x=
[ ] 21 2 3 4 1 2 3 4, , , /inv x x x x x x x x= −
( )( )( )( )
( )( )( )( )
1 2
* *
3 4
2 21 1 2 2
2 21 1 2 2 1 2 1
*2
*
22
*
1
*
11 1 1 1
11 1 1 1
Hx x x x
u u u
x x
uu u u u u u u u
=− − − −
−=
− −
−
− −
non-derivative techniques
1 1 2 2,u uφ φ→ → * * * *1 1 1 1 2 2 2 2, , ,u u u uφ φ φ φ→ → → →
2911/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
Molien-Weyl formula: representation theory
non-derivative techniques
{ }
1
2,
n
G g g g
φφ
φ
Φ
=
= Φ →
=
[ ]1 2, , , n R rg gφ φ φ → = ⊕
{ }1 21 2 1 2,nrr r
n n rr r r r gφ φ φ + + + = →
( ) singlet,0
?rr
r
H u c u∞
=
≡ =∑
3011/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
Molien-Weyl formula: representation theory
( ) ( ) ( )trr r a aa
g g c gχ χ== ∑( ) ( )*1
a b abg
g gG
χ χ δ=∑( )singlet,
1 1r rg
c gG
χ= ⋅∑
non-derivative techniques
[ ]1 2, , , n R rg gφ φ φ → = ⊕
{ }1 21 2 1 2,nrr r
n n rr r r r gφ φ φ + + + = →
( ) singlet,0
?rr
r
H u c u∞
=
≡ =∑{ }
1
2,
n
G g g g
φφ
φ
Φ
=
= Φ →
=
3111/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
Molien-Weyl formula: representation theory
( ) ( ) ( )single0
t,0
1 1 ,rr
rr R
g rr g
g u gG
c uG
H u u χ χ∞
=
∞
=
= ≡≡ ∑∑ ∑ ∑
( ) ( ) ( )trr r a aa
g g c gχ χ== ∑( ) ( )*1
a b abg
g gG
χ χ δ=∑( )singlet,
1 1r rg
c gG
χ= ⋅∑
non-derivative techniques
[ ]1 2, , , n R rg gφ φ φ → = ⊕
{ }1 21 2 1 2,nrr r
n n rr r r r gφ φ φ + + + = →
( ) singlet,0
?rr
r
H u c u∞
=
≡ =∑{ }
1
2,
n
G g g g
φφ
φ
Φ
=
= Φ →
=
3211/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
Molien-Weyl formula: representation theory
[ ]1 2, , , n R rg gφ φ φ → = ⊕
{ }1 21 2 1 2,nrr r
n n rr r r r gφ φ φ + + + = →
( ) ( ) ( )single0
t,0
1 1 ,rr
rr R
g rr g
g u gG
c uG
H u u χ χ∞
=
∞
=
= ≡≡ ∑∑ ∑ ∑
( ) ( ) ( )trr r a aa
g g c gχ χ== ∑( ) ( )*1
a b abg
g gG
χ χ δ=∑( )singlet,
1 1r rg
c gG
χ= ⋅∑
non-derivative techniques
( ) ( )0
, rR r
r
u g u gχ χ∞
=
≡ ∑ graded Ring (R) character
( ) singlet,0
?rr
r
H u c u∞
=
≡ =∑{ }
1
2,
n
G g g g
φφ
φ
Φ
=
= Φ →
=
3311/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
( ){ }
( ) ( )
1
1
1
†1 2
1 1
1
, dia ,
tr
g , ,
diag ,n
n
n
n
rr n
n
rn
rrr r
r r r
r r r
g
g
g
UD U D
g
λ λ λ
λ λ
χ λ λ
Φ Φ Φ
+ + =
=
+ =
=
=
+=
= ∑
non-derivative techniques
Molien-Weyl formula: representation theory
3411/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
( ) ( )
( ) ( ) ( ) ( )
11 1
1 1 2 01 1
0 0
1
1 1det 1 det 1
,
11 1
n
n n
nnr r r rr rr rR r
r r r r rn
rr rn
n
u g u g u u
u gu uD u
χ χ λ λ λ λ
λ λ
∞ ∞ ∞+
= = + + =
+
=
Φ Φ− −
≡ = =
= = =− −
∑ ∑ ∑ ∑
non-derivative techniques
Molien-Weyl formula: representation theory
( ){ }
( ) ( )
1
1
1
†1 2
1 1
1
, dia ,
tr
g , ,
diag ,n
n
n
n
rr n
n
rn
rrr r
r r r
r r r
g
g
g
UD U D
g
λ λ λ
λ λ
χ λ λ
Φ Φ Φ
+ + =
=
+ =
=
=
+=
= ∑
3511/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
( ) ( ) ( ) ( )1 1
de et 11
t 1 dGg
gug g
H du
uG
µΦ Φ− −
= =∑ ∫
non-derivative techniques
Molien-Weyl formula: representation theory
( ){ }
( ) ( )
1
1
1
†1 2
1 1
1
, dia ,
tr
g , ,
diag ,n
n
n
n
rr n
n
rn
rrr r
r r r
r r r
g
g
g
UD U D
g
λ λ λ
λ λ
χ λ λ
Φ Φ Φ
+ + =
=
+ =
=
=
+=
= ∑
( ) ( )
( ) ( ) ( ) ( )
11 1
1 1 2 01 1
0 0
1
1 1det 1 det 1
,
11 1
n
n n
nnr r r rr rr rR r
r r r r rn
rr rn
n
u g u g u u
u gu uD u
χ χ λ λ λ λ
λ λ
∞ ∞ ∞+
= = + + =
+
=
Φ Φ− −
≡ = =
= = =− −
∑ ∑ ∑ ∑
3611/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
Weyl integration formula
11 2 1 2~g hg h g g− →=
maximal torus generated by Cartan subalgebra
class function:( ) ( )1 2 1 2~ g f gg f g→ =
( ) ( ) ( ) ( )G GTd dg f g f g
αµ µ α α
∈ =∫ ∫
non-derivative techniques
3711/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
Weyl integration formula
11 2 1 2~g hg h g g− →=
maximal torus generated by Cartan subalgebra
class function:( ) ( )1 2 1 2~ g f gg f g→ =
( ) ( ) ( ) ( )G GTd dg f g f g
αµ µ α α
∈ =∫ ∫
( )2a ai tSU eg θ=⊃
( ) 3 /2,i t iT g e eθ θα α⊃ = ≡
( )1/2 1
00sgα
αα= −
≡
non-derivative techniques
3811/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
Weyl integration formula
11 2 1 2~g hg h g g− →=
maximal torus generated by Cartan subalgebra
class function:( ) ( )1 2 1 2~ g f gg f g→ =
( ) ( ) ( ) ( )G GTd dg f g f g
αµ µ α α
∈ =∫ ∫
( )2a ai tSU eg θ=⊃
( ) 3 /2,i t iT g e eθ θα α⊃ = ≡
( )1/2 1
00sgα
αα= −
≡
non-derivative techniques
W. Fulton and J. Harris, Representation Theory, Springer, New York, 2004
3911/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
A. Hanany and R. Kalveks, arXiv: 1408.4690
non-derivative techniques
( ) ( ) ( )( )
( ) ( )1 2
2 21 2
2 21 1 2 1 2
1 23 2 21 2 1 2 2 1 2 1
1 1
21
1 1 1, 1 12 2 2
1 1 1 11 1 1 1 1 12 2 6
U SU
SU
x y
z z
dx dyd d y yx y
dz dz z z z zd zz z z z z z z z
i i
zi i
µ µπ π
µπ π
= =
= =
−= = − −
= − − − − − −
∫ ∫ ∫ ∫
∫ ∫
Weyl integration formula
4011/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
( ) ( ) [ ]{ } [ ]{ }
( ) ( )( )
1 1
1 exp ln det 1 exp tr ln 1det 1
1 1exp tr exp
,
PE
R
r
r
r r r
r
ug ugug
u
u
g ur r
u
χ αα
χ α
χ α
Φ ΦΦ
∞ ∞
Φ Φ
Φ
= =
= − − = − −−
= =
=
≡
∑ ∑
( )( )
( )1e
E,1
Pd t a
a
R a aaa
a
uu g
uχ α χ αα Φ
Φ
=
= −∏ ∑
( ){ } ( )trr rgTα α χ αΦ Φ= ∈ →
non-derivative techniques
Plethystic Exponential
More than one generate multiplets: { }aΦ
4111/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
( ) ( ) ( ) ( )0
1
1
1
P1
1 , det 1 , expEFr
rr r
r
ruu r ug ur
χ α χ α= =
+∞
Φ Φ Φ −
= + + =
∑ ∑
non-derivative techniques
( ) ( ) ( )0 1
1 1 1, , exp1 de
P1
Et
r r r
r r
uu ur ug r
χ α χ α∞ ∞
Φ ΦΦ= =
= = − − ∑ ∑
A side note on fermionic fields
4211/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
( )( )
( )1e
E,1
Pd t a
a
R a aaa
a
uu g
uχ α χ αα Φ
Φ
=
= −∏ ∑
( ) ( ) ( ) ( )1 , ,R G R aTg
H u u g d uG α
χ µ α χ α∈
= =∑ ∫
non-derivative techniques
generator multiplet representation matrix generator multiplet character
graded R characterproject out singlet
Summary of Molien-Weyl formula
4311/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
( ) ( ) ( )( )1 2
2 21 2
112 1 1R R
uH e uu
Pu
χ χ= +
=+− −
( ) { }1 2 2
1 1 2 2
, , ,,
e PP
ZP
φ φφ φ φ φ
=
= − = −
( )( ) ( )( )
( )( ) ( )( )
1 2
1 2
1 11 1det 1
1 11 1det 1
a
a
a
R
a
a
Ra
u uu g
g P
e
Pu uu
eχ
χ
Φ
Φ
= =− − −
=+ + −
=
∏
∏
( ) { } ( ) { }1,1 1 1, ,a a
g e g PΦ Φ = −= −
{ } { }1 2 1 2, ,a au u uφ φΦ →= =
non-derivative techniques
Back to examples of imposing symmetry
4411/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
( )( ) ( )( )( )( )* 1 2 * 2
1 1 2 2
1 1,1 1 1 1det 1
a
R aa
a
u u u uu guχ α
α α α αα − −Φ
= − − −
=−− ∏
( ) ( ) ( )( )( )( )( )
( )( )( )( )
( )( )( )( )
1 * 1 2 * 211 1 2 2
2
2 * 2 *11 2 1 2
2 *2 *1 1 2 2
* * 2 * *21 1 2 2 1 2 1 2
1 1,2 1 1 1 1
2 1 1
11 1 1 1
R aUd
u u u u
du u u u
u u u uu u
H
u u u u u
d u
i
u
iα
α
αµ α χ απ α α α α α
α απ α α α α
− −=
=
=− − − −
=− − − −
−=
− −
=
− −
∫
∫
∫
( ) ( )* *1 1 2 2
21 1 2 2
, , , , 1
,i ie e
Uθ θ
φ φ φ φ
φ φ φ φ→ →
( ) { } { }2 2 1 2 2, , , , , ,a
i i i ie e eg eθ θ θ θα α α α α− − − −Φ = =
{ } { }* * * *1 1 2 2 1 1 2 2, , , , , ,a au u u u uφ φ φ φΦ →= =
non-derivative techniques
Back to examples of imposing symmetry
Need to accommodate derivative!
• warm up: 1d real scalar
• true task: higher d
4511/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
- EOM - IBP
warm up: 1d real scalar
EOM: removing generators
4611/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
2 0φ∂ =EOM:
[ ],EOM 1 2 21, , , , ,, NN Nφ φ φ φ φ φ∂= ∂ ∂ ( ) ( )( )M1
,EO1,
1 1a
N
aN a
a
H u tu tu=
=− −∏
2free ,, ,φ φ φ = ∂ ∂ ( )
( )( )( )free 2
1,1 1 1
H u tu tu t u
=− − −
ut
φ →∂ →
[ ]EOM ,φ φ∂= ( ) ( )( )EOM1,
1 1H u t
u tu=
− −
warm up: 1d real scalar
4711/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
IBP: highest weight states of SO(3,C)
φφ
Φ∂
=
A spin ½ representation of SO(3,C)derivative as a lowering operator
warm up: 1d real scalar
Calculation of Hilbert series
4811/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
( )( ) ( )( )
( )1
,EOM
1
1
1 1
1, ,det 1
a
R a N
a
aa
i
N
aa
gu
uH
uu
u αα αχ α α
−Φ
=
= −
=−
=−∏ ∏
( ) 1
0,
0aa aa
a
u gφ α
αφ αΦ −
Φ →
∂
= =
( ) ( ) ( ) ( ) ( ) ( )0 1 0 3,C*
0 100
,, Rr
N a r a SOr
rr
T arH u u u u uc u d
αµ α χ αχ α
∞
+ ∈
∞
+==
== ∑ ∑∫
( ) ( ) ( ) ( ) 21 1 1
0
, , r r ra r a r
rR ru c uχ α χ α χ α α α α
∞− −
+ + +=
= = + ++∑
( )( )2 2
1
1 1 12 2d
iα
α α απ α
−
=− −∫ ( )( )1
0 0
11 1u uα α−− −
2a au
tu α
α−
==
1/2~ pα −
warm up: 1d real scalar
4911/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
( ) ( ) ( )( )( )( )( )
2 22
0 110 0
11, 1 112 2 11 1
N Nb b
N ab
N
a b a aba aa b
u uH u u
i u u uud
uuα
α απ α α α
−
−==
≠=
−− = −
− − − − = ∫ ∏ ∑∏
Closed form results
( )( )( )
( )( )( )( )( )( )
1
1 2 2
1 3
10
20
1
0 1
0 23
0 2 3 2 30 1 1 2 30
11
11 1 1
11 1 1 1 1 1
Hu u
Hu u u u u u
u u u uHu u u u u u u u u u u u
=−
=− − −
−=
− − − − − −
warm up: 1d real scalar
Side remark: recursion relation (composition rule)
5011/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
( ) ( ) ( )20 ,EOM1
1 1 ,2
,N a N aH u u ui
d Hα
α α απ α=
−= ∫
( ) ( ) ( )1,EOM ,EOM 1,EOM 1, , ,N a N a NH Hu Hu uα α α+ +=
( ) ( ) ( )11 0 1 1 0 11 1 21
1 , ,, , , , , , ,2N N N Nx N NH u u u u u u x x ud ux H H
i xπ +−
+ + −== ∫
( ) ( ) ( )11 0 1 1 10 1 11
1 , ,, , , ,2
, , , ,N NM N M N N Mx N MH u u u u ud ux x xHx
H u uiπ
−+ − − −= ++ −= ∫
warm up: 1d real scalar
Side remark: composition rule in diagrams
5111/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
( )2 0 1 2, ,H u u u ( ) ( ) ( )21
2 0 1 2 3 0 1 31 3 2, , ,, , ,12
,x
d u u x x u u H u u u ux Hi
Hxπ
−
==∫
general composition:
warm up: 1d real scalar
1d method recap: two steps
5211/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
Find graded R character
Project out highest weight states
( )( )
( ),EOM1, ,
det 1a
a
R a N aa
u H uu g
χ α ααΦ −
= ∏
( ) ( ) ( ) ( ) ( )*0 3
0,C 0 1, ,r
rN Sr
aa O RH u d uu u χ αµ α χ α∞
+=
= ∑∫
true task: higher d
5311/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
• Lorentz invariance
Euclidean spacetime Molien-Weyl formula( )SO d
Can we generalize the 1d method to higher d?
true task: higher d
5411/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
• Lorentz invariance
Euclidean spacetime Molien-Weyl formula( )SO d
Can we generalize the 1d method to higher d?
free , ,, ,µ µ ν µ ν ρφ φ φ φ∂ ∂ ∂ ∂ ∂ = ∂ 2 0µ µφ φ∂ = ∂ ∂ =
• EOM does not truncate generators
EOMkφ∂ =
21 kµ µ µ φ∂ ∂ ∂traceless symmetric:kφ∂
true task: higher d
5511/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
• Lorentz invariance
Euclidean spacetime Molien-Weyl formula( )SO d
Can we generalize the 1d method to higher d?
free , ,, ,µ µ ν µ ν ρφ φ φ φ∂ ∂ ∂ ∂ ∂ = ∂ 2 0µ µφ φ∂ = ∂ ∂ =
• EOM does not truncate generators
EOMkφ∂ =
21 kµ µ µ φ∂ ∂ ∂traceless symmetric:kφ∂
• IBPA group where each µ∂ acts as a lowering operator?
true task: higher d
5611/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
• Lorentz invariance
Euclidean spacetime Molien-Weyl formula( )SO d
Can we generalize the 1d method to higher d?
free , ,, ,µ µ ν µ ν ρφ φ φ φ∂ ∂ ∂ ∂ ∂ = ∂ 2 0µ µφ φ∂ = ∂ ∂ =
• EOM does not truncate generators
EOMkφ∂ =
21 kµ µ µ φ∂ ∂ ∂traceless symmetric:kφ∂
• IBPA group where each µ∂ acts as a lowering operator?
( )2,SO d + ( )3,SO complexified conformal group
true task: higher d
5711/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
Can we generalize the 1d method to higher d?
( ),
2,,
D P PSO d
D K K
µ µ
µ µ
= − + = +
⊃
( ) { },2 , , ,SO d L P K Dµν µ µ⊃
conformal group
true task: higher d
5811/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
2
k
φφφ
φ
∂∂
Φ
=
∂
[ ]EOM Φ= Pµ
real scalar
Can we generalize the 1d method to higher d?
( ),
2,,
D P PSO d
D K K
µ µ
µ µ
= − + = +
⊃
( ) { },2 , , ,SO d L P K Dµν µ µ⊃
conformal group
true task: higher d
5911/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
scalar conformal primariesLorentz invariance, EOM, and IBP
2
k
φφφ
φ
∂∂
Φ
=
∂
[ ]EOM Φ= Pµ
real scalar
Can we generalize the 1d method to higher d?
( ),
2,,
D P PSO d
D K K
µ µ
µ µ
= − + = +
⊃
( ) { },2 , , ,SO d L P K Dµν µ µ⊃
conformal group
true task: higher d
6011/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
scalar conformal primariesLorentz invariance, EOM, and IBP
2 0, 0i ii
pp = =∑ ( ) ( ) ( )3# # cross ratios
2 2i j
n n npp n
−= − = =
2
k
φφφ
φ
∂∂
Φ
=
∂
[ ]EOM Φ= Pµ
real scalar
Can we generalize the 1d method to higher d?
( ),
2,,
D P PSO d
D K K
µ µ
µ µ
= − + = +
⊃
( ) { },2 , , ,SO d L P K Dµν µ µ⊃
conformal group
true task: higher d
6111/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
4d real scalar example
( ) ( ) ( ) ( )1 2 2 2
0 , 0
, tr, , 1 ,, ,k
k m k n k
k m n
g q qq q q P qχ α β α β α β α β∞
+ − −Φ Φ
= =
= − = =∑ ∑
( )( )( )( )( )1 1 1 1
1, ,1 1 1 1
P qq q q q
α βαβ αβ α β α β− − − −
≡− − − −
( ) ( ) ( )4 2 2L R
SO SU SU×
Lorentz group~ ,
2 2k k kφ Φ ⊃ ∂
( ) ( ) ( )1 2 2, ,, diag , , diag , , ,k k k k kk kg qq α β α α α β β β− −+ −Φ
−= ⊕ ⊗
k
Find graded R character
( ) ( ) ( )1
1ex ,, , , PE , , p ,r r rR
r
r
q qr
qχ φ α β φχ α β φ χ α β∞
ΦΦ=
=
≡ ∑
true task: higher d
6211/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
( ) ( ) ( )( )( )( )2 2 2
1421 1 1
4, 1 1
2 2SO i id dd
α β
α βµ α β α α β βπ π αβ
− −
= == − − − −∫ ∫
4d real scalar example
( ) ( ) ( ) ( )( ) ( )4 1 1 14,2 1
1, , ,,, ,,
12SO SO q
q dqd dq P qi P q
µ α β µ α βπ α β α β− − −=
=∫ ∫ ∫
( ) ( ), , , ,q q P qχ α β α β∆∆ =
Project out 0-spin primaries ( ) ( ) ( ); , , ,,, Lorentzll qq P qχ α β χ α β α β∆
∆ =
F. A. Dolan, arXiv: hep-th/0508031
( ) ( ) ( ) ( )*4,2 , , , , , ,SOd q q qµ α β χ α β χ α β δ′ ′∆ ∆ ∆∆=∫Orthonormality:
( ) ( )* 1 1 1 1 1 11
0 0
1, , , ,1
p p q P q P qpq
χ α β α β∞ ∞
∆ ∆ −∆ − − − − − −∆ −
∆= ∆=
= =−∑ ∑
( ) ( ) ( )4, 4*
20
1, SO OR RSpH p d dP
φ µ χ χ µ χ∞
∆∆
∆=
= =∑∫ ∫
true task: higher d
6311/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
One subtlety: unitarity bound
( ) ( ) ( ) ( ) ( )44 231, 1RSOH p d
POp ppφ µ χ φ φ= = − +++∫
F. A. Dolan, arXiv: hep-th/0508031
( ) ( ) ( ) ( )21, ,, , ,1 ,q q P q qqχ α β α β χ α βΦ − ==
( ) ( )( ) ( ) ( )1 1 3
, ,, , ,
, , ,
1
, , ,
q q
q q q
χ α β χ α β
χ α β χ α β χ α β∆ ∆ ∆=
−
>
=
unitarity bound, 01 l∆ ≥ =
unitarity bound is saturated( ) ( ), ,, ,q qχ α β χ α β∆ ∆≠
( ) ( ), , , ,q q P qχ α β α β∆∆ =
true task: higher d
6411/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
( ) ( ) ( ) ( ) ( ) ( ) ( )1 1 2 2 3 3, , 1 , ,, ,,, ,R q c q c q c qχ φ α β φ χ α β φ χ α β φ χ α β+ + += +
( ) ( ) ( ) ( )2 31 2 3, 1p c cH p p c pφ φ φ φ+ += + +
( )11 1 2 2 3 31R c c c cχ χ χ χ+ + −=− +
( ) ( )
( ) ( )( )
*4,2
* *1 34,23
,1 3
1
RS
R
O
SO
d
c
c
d
χ
χ
µ χ
µ χ χ
∆∆ − ∆ ≠=
= + −
∫∫
( ) ( ) ( )
( )
* * *1 04,
32
3 44
0
, 1 1
1
R
R
SO
SO
p d p p
dP
p p
H µ χ χ χφ
µ φ
χ
χ
∆
∞∆
∆=
+ −
+
=
−
=
−
+
∑∫
∫
One subtlety: unitarity bound
true task: higher d
6511/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
4d SM EFT
Find graded R character
{ }( ) ( )1 2 1 2, , , , , , , PE , , , , , ,aa
aaR q x zz q x y zzyχ α β φ χφ α βΦ
=
∑
Project out gauge invariant 0-spin primaries
{ }( ) ( ) ( ) ( ) ( ) { }( )
( )
1 2 1 24
4
1, , , , , , , , , , , ,, ,
1 PEa a
gauge
ga
a R aSO
conformal gaugeaSOuge
a
H p d x zy z d p x y zP p
d dP
zφ µ µ χ φ
µ
α β α βα β
µ χ χφ Φ Φ
=
=
∫ ∫
∑∫ ∫
( ) ( ) ( )1 2 1 2, , , , , , ,, ,,,a a a
conformal gaugeq x y z x yq zzz χ α β χχ α βΦ Φ Φ=
true task: higher d
6611/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
4d SM EFT
,L
R
i
i
X X XX X
X X Xµν µν µν ρσ
µν µνρσµν µν µν
≡ ≡≡
+
−
{ }, , , , , , , , . ., L L La c c cH Q u d L e G c cW Bµν µν µνΦ ∈
Field content
( )( ) ( )( ) ( )
~ 0,0
~ 1 2,0 , ~ 0,1 2
~ 1,0 , ~ 0,1L R
L RX Xµν µν
φ
ψ ψ
Lorentz group representations
{ }( ) ( )41, PE
aa
conforma gaugea gauge
aSO
laH p d d
Pφ µ µ χ χφ ΦΦ
=
∑∫ ∫
true task: higher d
6711/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
4d SM EFT
( ) ( ) ( )1 1 1 1
1 21 1
0
, ,, 1,k k k k
conformal k
k
q q P qq qφα α β βχ α β α βα α β β
+ − − + − −∞+
− −=
=− −− −
= −∑
( ) ( ) ( ) ( )2 2 1 1
3/2 3/2 1 11 1
0
, ,, ,L
k k k kconformal k
k
q qq q Pqψα α β βχ α β α α β β α βα α β β
+ − − + − −∞+ − −
− −=
− −= + − += − −∑
( ) ( ) ( )( ) ( )3 3 1 1
2 2 2 2 1 1 21 1
0
, , 1 ,,L
k k k kconformal kX
k
q Pq q qqq α α β βχ α β α α α α β β α βα α β β
+ − − + − −∞+ − − −
− −=
= + + − + + +− −− − = ∑
{ }( ) ( )41, PE
aa
conforma gaugea gauge
aSO
laH p d d
Pφ µ µ χ χφ ΦΦ
=
∑∫ ∫
~ ,2 2
1~ ,2 2
2~ ,2 2
k
kL
kL
k kD
k kD
k kD X
φ
ψ
+
+
2 00
0L
L
DDD Xµ
µν
φψ
=
=/ =
EOM ( ) ( )1 1 1 1
1 12, 2 ,m m n n
Lorentzm n
α α β βχ α βα α β β
+ − − + − −
− −− −− −
=
true task: higher d
6811/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
4d SM EFT
( ) ( ) ( ) ( ) ( ) ( ) ( )1 21 2 1
32, , ,,
a aa a
Ugauge SU SUx y z z x y zzχ χ χχ Φ ΦΦ Φ=
( ) ( ) ( ) ( ) ( ) ( ) ( ) ( )
( ) ( ) ( ) ( ) ( ) ( )
*1 2 2 21 2 22
2 2*3 3 32 1 2 2 11 2 1 2 1 1 2 1 23 2 2
1 2 2 1
2 adj
3 a2
dj1 1 2
, , 1
1 1, , , , 2
U SU SU SUQQ
SU SU SU
x x y y y y y y y
z z z z zz z z z zz z z z z z z z
z z z z
χ χ χ χ
χ χ χ
− − = = = + = + +
= = + + = + + + + + +
Gauge invariance ( ) ( ) ( )3 2 1c W Y
SU SU U× ×
{ }( ) ( )41, PE
aa
conformala
gauaSO
geg e
aaugH ddp
Pφ µµ χφ χΦ Φ
=
∑∫∫
( ) ( ) ( ) ( ) ( ) ( ) ( )1 211 2 32, , , ,U SU Sga ge Uu d xd x y z z d z zd yµ µµ µ=∫ ∫ ∫ ∫
( ) ( ) ( )( )
( ) ( )1 2
2 21 2
2 21 1 2 1 2
1 23 2 21 2 1 2 2 1 2 1
1 1
21
1 1 1, 1 12 2 2
1 1 1 11 1 1 1 1 12 2 6
U SU
SU
x y
z z
dx dyd d y yx y
dz dz z z z zd zz z z z z z z z
i i
zi i
µ µπ π
µπ π
= =
= =
−= = − −
= − − − − − −
∫ ∫ ∫ ∫
∫ ∫
true task: higher d
6911/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
1 generation
3 generations
SM EFT
931 by L. Lehman and A. Martin (LM), arXiv: 1510.00372
true task: higher d
7011/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
{ }( ) ( ) ( ) { }( ){ }( ) ( ) ( ) ( ) ( ) { }( )1/2,
EO
1/
M 4
,EOM 4 2
,
,
, , , ,
, , ,,,
RSO
LorentzD R
a
a SO
a
a
H d p
H d
p
p p
φ φ
φ
µ α β χ α β
µ α β χ α β φχ α β
=
=
∫∫
EOM 0A D Aµ µ µ∈ → =
0ADD AA DDA µ µ µ νµ ν µµ νν= → = =
What mistake did LM make?
{ }EOM ,EOM ,0max DpH H H−=LM method:
true task: higher d
7111/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
( )( )( ) ( )( ){ }( )( ) ( )( ){ }
† † † †EOM
† † † †EOM
,
,
L L
L L
D H D H H B D H H H D H B
H D H H B D H H H H B
H
H
µ ν µν µ ν µν
ν µν ν µν
⊃
⊃
( )( ) ( )( ) ( )2† † † † †12
L L LH D H H B D H H H H B D H H BHν µν ν µν ν µν + =
L. Lehman and A. Martin, arXiv: 1510.00372
B. Henning, XL, T. Melia and H. Murayama, arXiv: 1512.xxxxx
true task: higher d
7211/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
( )0# D Aµ µ= =The # of IBP
A D Aµ ν µν=
( ) ( )# #A D Aµ ν µν−
true task: higher d
7311/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
( )0# D Aµ µ= =The # of IBP
A D Aµ ν µν=
( ) ( )# #A D Aµ ν µν−
( ) ( )# #A D Aµν ρ µνρ−
true task: higher d
7411/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
( )0# D Aµ µ= =The # of IBP
A D Aµ ν µν=
( ) ( )# #A D Aµ ν µν−
( ) ( )# #A D Aµν ρ µνρ−
( ) ( )# #A D Aµνρ σ µνρσ−
true task: higher d
7511/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
( )0# D Aµ µ= =The # of IBP
A D Aµ ν µν=
( ) ( )# #A D Aµ ν µν−
( ) ( )# #A D Aµν ρ µνρ−
( ) ( )# #A D Aµνρ σ µνρσ−
( )# Aµνρσ
true task: higher d
7611/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
( )0# D Aµ µ= =The # of IBP
A D Aµ ν µν=
( ) ( )# #A D Aµ ν µν−
The # of IBP ( ) ( ) ( ) ( )# # # #A A A Aµ µν µνρ µνρσ= − + −
( ) ( )# #A D Aµν ρ µνρ−
( ) ( )# #A D Aµνρ σ µνρσ−
( )# Aµνρσ
true task: higher d
7711/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
( ) ( ) ( ) ( ) ( ){ }( ) ( )
1/2,1/2
2 3 42-form,EOM 3-form,EOM 4-form,
1,0 0,1 1/2,1/
EOM 1-form,EOM
2 3 44
4
2
EOM
1, ,
1 Lorentz Lorentz Lorentz LorentzRSO
RSO
p
p p
H H H
d
p H p H p H
p
d
p
P p
µ χ χ χ χ χ
µα
χβ
−
+ +
+=
= −
=
−
+
+
−
∫
∫ Then it is almost correct
( )( )( )( )1 1 1 11 1 1 1p p p pαβ αβ α β α β− − − −− − − −
What mistake did LM make?
true task: higher d
7811/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
General d case
( ) ( ), , PE ,R i iqxq xχ φ φχΦ=
( ) ( ) ( ) ( ) ( )*,
02, , , , ,SO d i i R ixH p d q qp x xqφ µ χ χ φ
∞∆
∆∆=
= ∑∫
Conformal representation of each field content:
scalar conformal primariesLorentz invariance, EOM, and IBP
( ) ( ) ( ) ( )( ) ( ),2 11
1 12 ,
,,i iSO d SO d q
i i
q x x dqd dq P q P qi x x
µ µπ −=
=∫ ∫ ∫
( )( )( )
( )( )
1
1
11 1
,1
1 11
1
i i
i
i i
qx qxP q
qx qx
x
q
−
−
− −=
−
−
−
( ) ( ), ,i ix q xq P qχ ∆∆ =
χ χ∆ ∆≠
when unitaritybound is saturated F. A. Dolan,
arXiv: hep-th/0508031
• Application: counting issue in other theories, such as ChPT?
• Deeper understanding: connection between Hilbert seriesand other observables?
Possible future direction
• technical: generalizing the recursion relation at 1d?
7911/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis
Thank you!
8011/30/2015 UC Davis Seminar Xiaochuan Lu, UC Davis