the spectra of yang-mills gauge theories with novel, non

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Introduction Features Results The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics Eoin Kerrane University of Edinburgh May 15, 2009 Eoin Kerrane University of Edinburgh The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

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Introduction Features Results

The Spectra of Yang-Mills Gauge Theories withnovel, non QCD-like dynamics

Eoin Kerrane

University of Edinburgh

May 15, 2009

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Table of contents

Introduction

Features

Results

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Outline

Introduction

Features

Results

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Motivation

I Why non QCD-like?

I Why not?I Several BSM applications relevant to LHC:

I TechnicolorI Unparticles

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Motivation

I Why non QCD-like?

I Why not?

I Several BSM applications relevant to LHC:I TechnicolorI Unparticles

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Motivation

I Why non QCD-like?

I Why not?I Several BSM applications relevant to LHC:

I TechnicolorI Unparticles

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Motivation

I Why non QCD-like?

I Why not?I Several BSM applications relevant to LHC:

I Technicolor

I Unparticles

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Motivation

I Why non QCD-like?

I Why not?I Several BSM applications relevant to LHC:

I TechnicolorI Unparticles

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Beta function

I SU(N) Yang-Mills theory, Nf fermions in representation R

β(g) = −β0(N,Nf ,R)g3

16π2− β1(N,Nf ,R)

g5

(16π2)2

I β0,1 > 0 for Nf small

I For QCD

β1 = 0 Nf ∼ 8

β0 = 0 Nf ∼ 16

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Beta function

I SU(N) Yang-Mills theory, Nf fermions in representation R

β(g) = −β0(N,Nf ,R)g3

16π2− β1(N,Nf ,R)

g5

(16π2)2

I β0,1 > 0 for Nf small

I For QCD

β1 = 0 Nf ∼ 8

β0 = 0 Nf ∼ 16

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Beta function

I SU(N) Yang-Mills theory, Nf fermions in representation R

β(g) = −β0(N,Nf ,R)g3

16π2− β1(N,Nf ,R)

g5

(16π2)2

I β0,1 > 0 for Nf small

I For QCD

β1 = 0 Nf ∼ 8

β0 = 0 Nf ∼ 16

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Beta function

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Beta function

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Beta function

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Beta function

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Bank-Zaks

I Non-trivial IR fixed-point first investigated in 1982 [BZ82]

I Began with observation that β0 < 0 for Nf > N∗ (N∗ ∼ 16)for QCD

I Then noticed:I that b1 < 0 for Nf > N ′f < N∗

I that form of β function is scheme dependent.

I Built an expansion in (Nf − N∗) of RG quantities forNf . N∗, where there is a weakly coupled IR fixed point

I Posited phase diagram of such a theoryI Concluded that theory with IR fixed point

I is scale invariantI does not admit a particle interpretation

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Bank-Zaks

I Non-trivial IR fixed-point first investigated in 1982 [BZ82]

I Began with observation that β0 < 0 for Nf > N∗ (N∗ ∼ 16)for QCD

I Then noticed:I that b1 < 0 for Nf > N ′f < N∗

I that form of β function is scheme dependent.

I Built an expansion in (Nf − N∗) of RG quantities forNf . N∗, where there is a weakly coupled IR fixed point

I Posited phase diagram of such a theoryI Concluded that theory with IR fixed point

I is scale invariantI does not admit a particle interpretation

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Bank-Zaks

I Non-trivial IR fixed-point first investigated in 1982 [BZ82]

I Began with observation that β0 < 0 for Nf > N∗ (N∗ ∼ 16)for QCD

I Then noticed:I that b1 < 0 for Nf > N ′f < N∗

I that form of β function is scheme dependent.

I Built an expansion in (Nf − N∗) of RG quantities forNf . N∗, where there is a weakly coupled IR fixed point

I Posited phase diagram of such a theoryI Concluded that theory with IR fixed point

I is scale invariantI does not admit a particle interpretation

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Bank-Zaks

I Non-trivial IR fixed-point first investigated in 1982 [BZ82]

I Began with observation that β0 < 0 for Nf > N∗ (N∗ ∼ 16)for QCD

I Then noticed:I that b1 < 0 for Nf > N ′f < N∗

I that form of β function is scheme dependent.

I Built an expansion in (Nf − N∗) of RG quantities forNf . N∗, where there is a weakly coupled IR fixed point

I Posited phase diagram of such a theoryI Concluded that theory with IR fixed point

I is scale invariantI does not admit a particle interpretation

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Bank-Zaks

I Non-trivial IR fixed-point first investigated in 1982 [BZ82]

I Began with observation that β0 < 0 for Nf > N∗ (N∗ ∼ 16)for QCD

I Then noticed:I that b1 < 0 for Nf > N ′f < N∗

I that form of β function is scheme dependent.

I Built an expansion in (Nf − N∗) of RG quantities forNf . N∗, where there is a weakly coupled IR fixed point

I Posited phase diagram of such a theoryI Concluded that theory with IR fixed point

I is scale invariantI does not admit a particle interpretation

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Bank-Zaks

I Non-trivial IR fixed-point first investigated in 1982 [BZ82]

I Began with observation that β0 < 0 for Nf > N∗ (N∗ ∼ 16)for QCD

I Then noticed:I that b1 < 0 for Nf > N ′f < N∗

I that form of β function is scheme dependent.

I Built an expansion in (Nf − N∗) of RG quantities forNf . N∗, where there is a weakly coupled IR fixed point

I Posited phase diagram of such a theory

I Concluded that theory with IR fixed pointI is scale invariantI does not admit a particle interpretation

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Bank-Zaks

I Non-trivial IR fixed-point first investigated in 1982 [BZ82]

I Began with observation that β0 < 0 for Nf > N∗ (N∗ ∼ 16)for QCD

I Then noticed:I that b1 < 0 for Nf > N ′f < N∗

I that form of β function is scheme dependent.

I Built an expansion in (Nf − N∗) of RG quantities forNf . N∗, where there is a weakly coupled IR fixed point

I Posited phase diagram of such a theoryI Concluded that theory with IR fixed point

I is scale invariant

I does not admit a particle interpretation

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Bank-Zaks

I Non-trivial IR fixed-point first investigated in 1982 [BZ82]

I Began with observation that β0 < 0 for Nf > N∗ (N∗ ∼ 16)for QCD

I Then noticed:I that b1 < 0 for Nf > N ′f < N∗

I that form of β function is scheme dependent.

I Built an expansion in (Nf − N∗) of RG quantities forNf . N∗, where there is a weakly coupled IR fixed point

I Posited phase diagram of such a theoryI Concluded that theory with IR fixed point

I is scale invariantI does not admit a particle interpretation

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Unparticles [Geo07]

I Proposed possibility of existence of BZ sector with IR fixedpoint, coupled to SM via particles of mass MU

I Below ΛU scale invariance emerges in BZ sector

I Analyses matrix elements of BZ operators

I Concludes that “unparticle stuff with scale dimension dU lookslike a non-integral number dU of invisible particles”

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Unparticles [Geo07]

I Proposed possibility of existence of BZ sector with IR fixedpoint, coupled to SM via particles of mass MU

I Below ΛU scale invariance emerges in BZ sector

I Analyses matrix elements of BZ operators

I Concludes that “unparticle stuff with scale dimension dU lookslike a non-integral number dU of invisible particles”

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Unparticles [Geo07]

I Proposed possibility of existence of BZ sector with IR fixedpoint, coupled to SM via particles of mass MU

I Below ΛU scale invariance emerges in BZ sector

I Analyses matrix elements of BZ operators

I Concludes that “unparticle stuff with scale dimension dU lookslike a non-integral number dU of invisible particles”

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Unparticles [Geo07]

I Proposed possibility of existence of BZ sector with IR fixedpoint, coupled to SM via particles of mass MU

I Below ΛU scale invariance emerges in BZ sector

I Analyses matrix elements of BZ operators

I Concludes that “unparticle stuff with scale dimension dU lookslike a non-integral number dU of invisible particles”

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Conformal Technicolor

I Suggested [LO06, Lut09] as alternative to Walking Technicolor

I Again, proposes BZ sector with IR fixed point

I 2 massless fermions forming minimal technicor sector

I Nf − 2 electroweak singlet fermions , charged under BZ withexplicit mass terms

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Conformal Technicolor

I Suggested [LO06, Lut09] as alternative to Walking Technicolor

I Again, proposes BZ sector with IR fixed point

I 2 massless fermions forming minimal technicor sector

I Nf − 2 electroweak singlet fermions , charged under BZ withexplicit mass terms

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Conformal Technicolor

I Suggested [LO06, Lut09] as alternative to Walking Technicolor

I Again, proposes BZ sector with IR fixed point

I 2 massless fermions forming minimal technicor sector

I Nf − 2 electroweak singlet fermions , charged under BZ withexplicit mass terms

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Conformal Technicolor

I Suggested [LO06, Lut09] as alternative to Walking Technicolor

I Again, proposes BZ sector with IR fixed point

I 2 massless fermions forming minimal technicor sector

I Nf − 2 electroweak singlet fermions , charged under BZ withexplicit mass terms

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Conformal Technicolor

I Theory is in conformal phase above TeV scale

I Fermion masses cause flow away from fixed point below TeV

I Scale-invariance broken, theory becomes confining, breakingEW

I Proximity to IR fixed point ensures condensate has largeanomalous dimension

I Fermion masses are enhanced, as in Walking Technicolor

I Argued in [San08] that CT is equivalent to Partially GaugedTechnicolor [DST06], but needs new mass scale for EWSB

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Conformal Technicolor

I Theory is in conformal phase above TeV scale

I Fermion masses cause flow away from fixed point below TeV

I Scale-invariance broken, theory becomes confining, breakingEW

I Proximity to IR fixed point ensures condensate has largeanomalous dimension

I Fermion masses are enhanced, as in Walking Technicolor

I Argued in [San08] that CT is equivalent to Partially GaugedTechnicolor [DST06], but needs new mass scale for EWSB

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Conformal Technicolor

I Theory is in conformal phase above TeV scale

I Fermion masses cause flow away from fixed point below TeV

I Scale-invariance broken, theory becomes confining, breakingEW

I Proximity to IR fixed point ensures condensate has largeanomalous dimension

I Fermion masses are enhanced, as in Walking Technicolor

I Argued in [San08] that CT is equivalent to Partially GaugedTechnicolor [DST06], but needs new mass scale for EWSB

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Conformal Technicolor

I Theory is in conformal phase above TeV scale

I Fermion masses cause flow away from fixed point below TeV

I Scale-invariance broken, theory becomes confining, breakingEW

I Proximity to IR fixed point ensures condensate has largeanomalous dimension

I Fermion masses are enhanced, as in Walking Technicolor

I Argued in [San08] that CT is equivalent to Partially GaugedTechnicolor [DST06], but needs new mass scale for EWSB

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Conformal Technicolor

I Theory is in conformal phase above TeV scale

I Fermion masses cause flow away from fixed point below TeV

I Scale-invariance broken, theory becomes confining, breakingEW

I Proximity to IR fixed point ensures condensate has largeanomalous dimension

I Fermion masses are enhanced, as in Walking Technicolor

I Argued in [San08] that CT is equivalent to Partially GaugedTechnicolor [DST06], but needs new mass scale for EWSB

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Conformal Technicolor

I Theory is in conformal phase above TeV scale

I Fermion masses cause flow away from fixed point below TeV

I Scale-invariance broken, theory becomes confining, breakingEW

I Proximity to IR fixed point ensures condensate has largeanomalous dimension

I Fermion masses are enhanced, as in Walking Technicolor

I Argued in [San08] that CT is equivalent to Partially GaugedTechnicolor [DST06], but needs new mass scale for EWSB

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Outline

Introduction

Features

Results

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Critical Line

I Yang-Mills spectra measured non-perturbatively in a latticeformulation

, Wilson fermions

I Chiral symmetry broken m0 6= mq

κ =1

8 + 2am0β =

4

g20

I Chirally symmetric phase has mπ,ρ,... → 0 as mq → 0

I Chirally broken phase has mπ ∼√

mq, mρ,... 9 0 as mq → 0

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Critical Line

I Yang-Mills spectra measured non-perturbatively in a latticeformulation, Wilson fermions

I Chiral symmetry broken m0 6= mq

κ =1

8 + 2am0β =

4

g20

I Chirally symmetric phase has mπ,ρ,... → 0 as mq → 0

I Chirally broken phase has mπ ∼√

mq, mρ,... 9 0 as mq → 0

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Critical Line

I Yang-Mills spectra measured non-perturbatively in a latticeformulation, Wilson fermions

I Chiral symmetry broken m0 6= mq

κ =1

8 + 2am0β =

4

g20

I Chirally symmetric phase has mπ,ρ,... → 0 as mq → 0

I Chirally broken phase has mπ ∼√

mq, mρ,... 9 0 as mq → 0

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Critical Line

I Yang-Mills spectra measured non-perturbatively in a latticeformulation, Wilson fermions

I Chiral symmetry broken m0 6= mq

κ =1

8 + 2am0β =

4

g20

I Chirally symmetric phase has mπ,ρ,... → 0 as mq → 0

I Chirally broken phase has mπ ∼√

mq, mρ,... 9 0 as mq → 0

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Critical Line

I Yang-Mills spectra measured non-perturbatively in a latticeformulation, Wilson fermions

I Chiral symmetry broken m0 6= mq

κ =1

8 + 2am0β =

4

g20

I Chirally symmetric phase has mπ,ρ,... → 0 as mq → 0

I Chirally broken phase has mπ ∼√

mq, mρ,... 9 0 as mq → 0

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Outline

Introduction

Features

Results

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

[CS07]

Figure: Fundamental quarks Figure: Adjoint quarks

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

[DDPP08]

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

[DDPP08]

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

[HRRT09]

Figure: Phase diagram of SU(2) adjoint theory

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

[HRRT09]

Figure: Fundamental Figure: Adjoint

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

[HRRT09]

Figure: Fundamental Figure: Adjoint

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Tom Banks and A. Zaks.On the Phase Structure of Vector-Like Gauge Theories withMassless Fermions.Nucl. Phys., B196:189, 1982.

Simon Catterall and Francesco Sannino.Minimal walking on the lattice.Phys. Rev., D76:034504, 2007.

Luigi Del Debbio, Agostino Patella, and Claudio Pica.Higher representations on the lattice: numerical simulations.SU(2) with adjoint fermions.2008.

Dennis D. Dietrich, Francesco Sannino, and Kimmo Tuominen.

Light composite Higgs and precision electroweakmeasurements on the Z resonance: An update.

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Phys. Rev., D73:037701, 2006.

Howard Georgi.Unparticle Physics.Phys. Rev. Lett., 98:221601, 2007.

Ari J. Hietanen, Jarno Rantaharju, Kari Rummukainen, andKimmo Tuominen.Spectrum of SU(2) lattice gauge theory with two adjoint Diracflavours.JHEP, 05:025, 2009.

Markus A. Luty and Takemichi Okui.Conformal technicolor.JHEP, 09:070, 2006.

Markus A. Luty.Strong Conformal Dynamics at the LHC and on the Lattice.JHEP, 04:050, 2009.

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics

Introduction Features Results

Francesco Sannino.(Near) Conformal Technicolor: What is really new?2008.

Eoin Kerrane University of Edinburgh

The Spectra of Yang-Mills Gauge Theories with novel, non QCD-like dynamics