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More Seiberg duality SO ( N ) gauge theory with F quarks in the - PowerPoint PPT Presentation

More Seiberg duality SO ( N ) gauge theory with F quarks in the vector representation SO ( N ) SU ( F ) U (1) R F +2 N Q F discrete for N > 3, axial Z 2 F symmetry Q e 2 i/ 2 F Q for N = 3 there is a discrete axial Z 4 F symmetry


  1. More Seiberg duality

  2. SO ( N ) gauge theory with F quarks in the vector representation SO ( N ) SU ( F ) U (1) R F +2 − N Q F discrete for N > 3, axial Z 2 F symmetry Q → e 2 πi/ 2 F Q for N = 3 there is a discrete axial Z 4 F symmetry one-loop β function coefficient, for N > 4 is b = 3( N − 2) − F no dynamical spinors, static spinor sources cannot be screened distinction between area-law confining and Higgs phases

  3. SO ( N ) group theory adjoint of SO ( N ) is two-index antisymmetric tensor odd N , there is one spinor representation even N there are two inequivalent spinors for N = 4 k the spinors are self-conjugate for N = 4 k + 2 the two spinors are complex conjugates

  4. SO ( N ) group theory SO (2 N + 1) Irrep r d ( r ) 2 T ( r ) 2 N + 1 2 2 N 2 N − 2 S N (2 N + 1) 4 N − 2 ( N + 1)(2 N + 1) − 1 4 N + 6 SO (2 N ) Irrep r d ( r ) 2 T ( r ) 2 N 2 2 N − 1 2 N − 3 S, S N (2 N − 1) 4 N − 4 N (2 N + 1) − 1 4 N + 4 S denotes a spinor, and S denotes the conjugate spinor

  5. The SO ( N ) moduli space F < N D-flatness conditions (up to flavor transformations):   v 1   ...       v F   � Φ � =   0 . . . 0     . . . .   . . 0 . . . 0 generic point in the classical moduli space SO ( N ) → SO ( N − F ) NF − N ( N − 1) + ( N − F )( N − F − 1) massless chiral supermultiplets

  6. The SO ( N ) moduli space F ≥ N   v 1 0 . . . 0   . . ... . . � Φ � =   . . v N 0 . . . 0 generic point in the moduli space the SO ( N ) broken completely NF − N ( N − 1) massless chiral supermultiplets. describe light degrees of freedom by “meson” and (for F ≥ N ) “baryon” fields: M ji = Φ j Φ i B [ i 1 ,...,i N ] = Φ [ i 1 . . . Φ i N ]

  7. The SO ( N ) moduli space F ≥ N Up to flavor transformations:   v 2 1   ...       v 2   N � M � =   0     ...   0 � B 1 ,...,N � = v 1 . . . v N rank of M is at most N √ det ′ M If the rank of M is N , then B = ±

  8. The SO ( N ) F < N − 2 U (1) A U (1) R W a 0 1 Λ b 2 F 0 det M 2 F 2( F + 2 − N ) ADS superpotential: � � 1 / ( N − 2 − F ) Λ b W dyn = c N,F det M

  9. Duality for SO ( N ) F ≥ 3( N − 2) lose asymptotic freedom F just below 3( N − 2) we have an IR fixed point solution to the anomaly matching for F > N − 2, is given by: SO ( F − N + 4) SU ( F ) U (1) R N − 2 q F 2( F +2 − N ) M 1 F For F > N − 1, N > 3 unique superpotential W = M ji 2 µ φ j φ i dual baryon operators: [ i 1 ,...,i � N ] i � N ] φ [ i 1 . . . φ � B =

  10. Hybrid “Baryon” Operators since adjoint is an antisymmetric tensor. In SO ( N ) we have: W 2 h [ i 1 ,...,i N − 4 ] = α Φ [ i 1 . . . Φ i N − 4 ] H [ i 1 ,...,i N − 2 ] α = W α Φ [ i 1 . . . Φ i N − 4 ] While in the dual theory we have: [ i 1 ,...,i � N − 4 ] i � N − 4 ] � � α φ [ i 1 . . . φ W 2 h = [ i 1 ,...,i � N − 2 ] i � N − 4 ] � � W α φ [ i 1 . . . φ H = α The two theories thus have a mapping of mesons, baryons, and hy- brids: M ↔ M , i 1 ,...,i � B i 1 ,...,i N ↔ ǫ i 1 ,...,i F � h N − 4 i 1 ,...,i � h i 1 ,...,i N − 4 ↔ ǫ i 1 ,...,i F � B N [ i 1 ,...,i � N − 2 ] H [ i 1 ,...,i N − 2 ] ↔ ǫ i 1 ,...,i F � H α α

  11. Dual one-loop β function g 3 (3( � g 3 (2 F − 3( N − 2)) β ( � g ) ∝ − � N − 2) − F ) = − � lose asymptotic freedom when F ≤ 3( N − 2) / 2 When F = 3( � N − 2) − ǫ � N perturbative IR fixed point in the dual theory SO ( N ) with F vectors has an interacting IR fixed point for 3( N − 2) / 2 < F < 3( N − 2) N − 2 ≤ F ≤ 3( N − 2) / 2 IR free massless composite gauge bosons, quarks, mesons, and their superpartners

  12. Special case: F ≤ N − 5 SO ( N ) → SO ( N − F ) ⊃ SO (5) gaugino condensation, dynamical superpotential: � � 1 / ( N − 2 − F ) 16Λ 3( N − 2) − F W dyn ∝ � λλ � ∝ det M runaway vacua

  13. Special case: F = N − 4 SO ( N ) → SO (4) ∼ SU (2) L × SU (2) R two gaugino condensates � � 1 / 2 16Λ 2 N − 1 W cond . = 2 � λλ � L + 2 � λλ � R = 1 2 ( ǫ L + ǫ R ) det M ǫ L,R = ± 1 two physically distinct branches: ( ǫ L + ǫ R ) = ± 2 and ( ǫ L + ǫ R ) = 0 first branch has runaway vacua, second has a quantum moduli space. at M = 0, M satisfies the ‘t Hooft anomaly matching confinement without chiral symmetry breaking, no baryons Integrating out a flavor on first branch gives runaway ( F = N − 5) second branch no SUSY vacua

  14. Special case: F = N − 3 SO ( N ) → SO (4) ∼ SU (2) L × SU (2) R → SU (2) d ∼ SO (3) instanton effects (Π 3 ( G/H ) = Π 3 ( SU (2)) = Z ) and gaugino condensation W inst . +cond . = 4(1 + ǫ ) Λ 2 N − 3 det M two phases of the gaugino condensate two physically distinct branches: ǫ = 1 and with ǫ = − 1 first has runaway vacua, while the second has a quantum moduli space Integrating out a flavor, we would need to find two branches again so W � = 0 even on the second branch

  15. Special case: F = N − 3 must have some other fields anomaly matching given by: SU ( F ) U (1) R N − 2 q F 2( F +2 − N ) M F most general superpotential � � det M Mqq 1 W = 2 µ Mqq f Λ 2 N − 2 where f ( t ) is an unknown function adding a mass term gives q F = ± iv which gives correct number of ground states q ↔ h = Q N − 4 W α W α confinement without chiral symmetry breaking with hybrids

  16. Special case: F = N − 1 Starting with the F = N dual which has an SO (4) gauge group, and integrating out a flavor there will be instanton effects when we break to SO (3) dual superpotential is modified in the case F = N − 1 to be: 2 µ φ j φ i − W = M ji 1 64Λ 2 N − 5 det M

  17. Special case: F = N − 2 both descriptions generically break to SO (2) ∼ U (1) monopoles

  18. SUSY Sp (2 N ) An Sp (2 N ) gauge theorywith 2 F quarks ( F flavors) in the fundamen- tal representation has a global SU (2 F ) × U (1) R symmetry as follows: Sp (2 N ) SU (2 F ) U (1) R F − 1 − N Q F adjoint of Sp (2 N ) is the two-index symmetric tensor

  19. Sp (2 N ) Representations Sp (2 N ) Irrep r d ( r ) T ( r ) 2 N 1 N (2 N − 1) − 1 2 N − 2 N (2 N + 1) 2 N + 2 N (2 N − 1)(2 N − 2) (2 N − 3)(2 N − 2) − 2 N − 1 3 2 N (2 N +1)(2 N +2) (2 N +2)(2 N +3) 3 2 (2 N ) 2 − 4 2 N (2 N − 1)(2 N +1) − 2 N 3 dimension smaller by − 1 than naive expectation invariant tensor of Sp (2 N ) is ǫ ij representation formed with two antisymmetric indices is reducible

  20. SUSY Sp (2 N ) one-loop β function for N > 4 is b = 3(2 N + 2) − 2 F moduli space is parameterized by a “meson” M ji = Φ j Φ i antisymmetric in the flavor indices i, j holomorphic intrinsic scale considered as a spurion field Pfaffian of a 2 F × 2 F matrix M is given by Pf M = ǫ i 1 ...i 2 F M i 1 i 2 . . . M i 2 F − 1 i 2 F U (1) A U (1) R Λ b/ 2 2 F 0 Pf M 2 F 2( F − 1 − N )

  21. SUSY Sp (2 N ) for F < N + 1 possible to generate a dynamical superpotential � � 1 / ( N +1 − F ) b Λ 2 W dyn ∝ Pf M For F = N + 1 one finds confinement with chiral symmetry breaking Pf M = Λ 2( N +1) For F = N + 2 one finds s-confinement with a superpotential: W = Pf M

  22. Duality for Sp (2 N ) solution to the anomaly matching for F > N − 2: Sp (2( F − N − 2)) SU (2 F ) U (1) R N +1 q F 2( F − 1 − N ) M 1 F a unique superpotential: W = M ji µ φ j φ i For 3( N + 1) / 2 < F < 3( N + 1) we have an IR fixed point For N + 3 ≤ F ≤ 3( N + 1) / 2 the dual is IR free

  23. Why chiral gauge theories are interesting vector-like theory we can give masses to all the matter fields → pure YM, gaugino condensation but no SUSY breaking Witten’s index argument: number of bosonic minus fermionic vacua does not change If taking the mass to zero does not move some vacua in from or out to infinity, then the massless theory has unbroken SUSY

  24. first example of a chiral gauge theory SU ( N ) SU ( N + 4) Q T 1 dual to SO (8) SU ( N + 4) q p S 1 U ∼ det T 1 1 M ∼ QTQ 1 with a superpotential W = Mqq + Upp This dual theory is vector-like!

  25. chiral dual of vector theory The dual β function coefficient is: b = 3(8 − 2) − ( N + 4) − 1 = 13 − N So the dual is IR free for N > 13

  26. Csaki, Schmaltz, Skiba

  27. S-Confinement SU ( N ) with N + 1 flavors. � � 1 W = det M − BMB Λ 2 N − 1 meson–baryon description was valid over the whole moduli space smooth description with no phase transitions theory has complementarity, static source screened by squarks To generalize: need fields that are fundamentals of SU or Sp and spinors of SO only consider theories with superpotential in the confined description Theories that satisfy these conditions are called s-confining

  28. S-Confinement single gauge group G , choose U (1) R such that G U (1) R φ i q r i φ j � = i 0 r j q is determined by anomaly cancellation: ( q − 1) T ( r i ) + T ( Ad ) − � 0 = j � = i T ( r j ) q T ( r i ) + T ( Ad ) − � = j T ( r j ) can do this for any field, and for each choice the superpotential has R -charge 2, we have � T ( r i ) � 2 / ( � � � j T ( r j ) − T ( Ad )) φ i W ∝ Λ 3 Π i Λ in general, a sum of terms with different contractions of gauge indices

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