Reduction of Couplings in Finite Thories and in the MSSM

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1 Reduction of Couplings in Finite Thories and in the MSSM Myriam Mondragón IFUNAM Sven Heinemeyer Nick Tracas George Zoupanos Corfu, September 2016

2 What happens as we approach the Planck scale? or just as we go up in energy... How do we go from a fundamental theory to field theory as we know it? How are the gauge, Yukawa and Higgs sectors related at a more fundamental level? How do particles get their very different masses? What is the nature of the Higgs? Is there one or many? How this affects all the above? Where is the new physics??

3 Search for understanding relations between parameters addition of symmetries. N = 1 SUSY GUTs. Complementary approach: look for RGI relations among couplings at GUT scale Planck scale reduction of couplings resulting theory: less free parameters more predictive

4 Gauge Yukawa Unification GYU Remarkable: reduction of couplings provides a way to relate two previously unrelated sectors gauge and Yukawa couplings Reduction of couplings in third generation provides predictions for quark masses (top and bottom) Including soft breaking terms gives Higgs masses and SUSY spectrum Kapetanakis, M.M., Zoupanos (1993), Kubo, M.M., Olechowski, Tracas, Zoupanos (1995,1996,1997); Oehme (1995); Kobayashi, Kubo, Raby, Zhang (2005); Gogoladze, Mimura, Nandi (2003,2004); Gogoladze, Li, Senoguz, Shafi, Khalid, Raza (2006,2011); M.M., Tracas, Zoupanos (2014)

5 Gauge Yukawa Unification in Finite Theories Dimensionless sector of all-loop finite SU(5) model M top 178 GeV large tan β, heavy SUSY spectrum Kapetanakis, M.M., Zoupanos, Z.f.Physik (1993) M exp top 176 ± 18 GeV found in 1995 Mtop th M exp top ±.09 GeV 2013 Very promising, a more detailed analysis was clearly needed M exp H Higgs mass GeV Heinemeyer M.M., Zoupanos, JHEP, 2007; Phys.Lett.B (2013) 126 ± 1 GeV 2013

6 Gauge Yukawa Unification in the MSSM Possible to have a reduced system in the third generation compatible with quark masses large tan β, heavy SUSY spectrum Higgs mass GeV M.M., Tracas, Zoupanos, Phys.Lett.B 2014

7 Reduction of Couplings A RGI relation among couplings Φ(g 1,..., g N ) = 0 satisfies µ dφ/dµ = N β i Φ/ g i = 0. i=1 g i = coupling, β i its β function Finding the (N 1) independent Φ s is equivalent to solve the reduction equations (RE) β g (dg i /dg) = β i, i = 1,, N Reduced theory: only one independent coupling and its β function complete reduction: power series solution of RE g a = n=0 ρ (n) a g 2n+1

8 uniqueness of the solution can be investigated at one-loop valid at all loops Zimmermann, Oehme, Sibold (1984,1985) The complete reduction might be too restrictive, one may use fewer Φ s as RGI constraints Reduction of couplings is essential for finiteness finiteness: absence of renormalizations β N = 0 SUSY no-renormalization theorems only study one and two-loops guarantee that is gauge and reparameterization invariant to all loops

9 Reduction of couplings: example without symmetry One Dirac spinor ψ and one pseudoscalar B in renormalizable interaction L int = g ψbγ 5 ψ λ 4! B4 β functions at one-loop order are β g 2 = 1 16π 2 (5g4 +...) β λ = 1 16π 2 (3 2 λ2 + 4λg 2 24g 4...)

10 We solve the reduction equations β g 2 with a power series solution dλ dg 2 = β λ λ = g 2 (ρ (0) + ρ (1) g 2 ) The only possible solution for small g is λ = 1 3 ( )g 2 + ρ (1) g The two coupling model has been reduced to a one coupling renormalizable one. Quartic coupling constant determined uniquely by Yukawa coupling No symmetries are known for this system symmetries need not be the only way to reduce couplings consistently

11 Reduction of couplings: example with symmetry Consider an SU(N) gauge theory with the following matter content: φ i (N) and ˆφ i (N) are complex scalars ψ i (N) and ˆψ i (N) are left-handed Weyl spinors λ a (a = 1,..., N 2 1) is right-handed Weyl spinor in the adjoint representation of SU(N). The Lagrangian is: L = 1 4 F a µνf a µν + i 2{ g Y ψλ a T a φ ĝ Y ˆψλ a T a ˆφ + h.c. } V (φ, φ), V (φ, φ) = 1 4 λ 1(φ i φ i ) λ 2( ˆφ i ˆφ i ) 2 +λ 3 (φ i φ i )( ˆφ j ˆφ j ) + λ 4 (φ i φ j )( ˆφ i ˆφ j ),

12 Applying the REs method and searching for a power solution we get: g Y = ĝ Y = g, λ 1 = λ 2 = N 1 N g2, λ 3 = 1 2N g2, λ 4 = 1 2 g2. which corresponds to an N = 1 supersymmetric gauge theory SUSY solutions appear in many cases when the RE method is applied

13 Reduction of couplings: the Standard Model It is possible to make a reduced system in the Standard Model in the matter sector: solve the REs, reduce the Yukawa and Higgs in favour of α S gives α t /α s = ; α λ/α s = border line in RG surface, Pendleton-Ross infrared fixed line But including the corrections due to non-vanishing gauge couplings up to two-loops, changes these relations and gives M t = 98.6 ± 9.2GeV and M h = 64.5 ± 1.5GeV Both out of the experimental range Kubo, Sibold and Zimmermann, 1984, 1985

14 General asymptotic reduction in SM More parameters (couplings): if top and Higgs heavy new physics heavy Kubo, Sibold and Zimmermann, 1985; Sibold and Zimmermann, 1987

15 Finiteness A chiral, anomaly free, N = 1 globally supersymmetric gauge theory based on a group G with gauge coupling constant g has a superpotential W = 1 2 mij Φ i Φ j Cijk Φ i Φ j Φ k, Requiring one-loop finiteness β (1) g following conditions: T (R i ) = 3C 2 (G), i = 0 = γ j(1) i gives the 1 2 C ipqc jpq = 2δ j i g2 C 2 (R i ). C 2 (G) quadratic Casimir invariant, T (R i ) Dynkin index of R i, C ijk Yukawa coup., g gauge coup. restricts the particle content of the models relates the gauge and Yukawa sectors

16 One-loop finiteness two-loop finiteness Jones, Mezincescu and Yao (1984,1985) One-loop finiteness restricts the choice of irreps R i, as well as the Yukawa couplings Cannot be applied to the susy Standard Model (SSM): C 2 [U(1)] = 0 The finiteness conditions allow only SSB terms It is possible to achieve all-loop finiteness β n = 0: 1. One-loop finiteness conditions must be satisfied Lucchesi, Piguet, Sibold 2. The Yukawa couplings must be a formal power series in g, which is solution (isolated and non-degenerate) to the reduction equations

17 SUSY breaking soft terms Introduce over 100 new free parameters

18 RGI in the Soft Supersymmetry Breaking Sector Supersymmetry is essential. It has to be broken, though... L SB = 1 6 hijk φ i φ j φ k bij φ i φ j (m2 ) j i φ i φ j + 1 M λλ + H.c. 2 h trilinear couplings (A), b ij bilinear couplings, m 2 squared scalar masses, M unified gaugino mass The RGI method has been extended to the SSB of these theories. One- and two-loop finiteness conditions for SSB have been known for some time Jack, Jones, et al. It is also possible to have all-loop RGI relations in the finite and non-finite cases Kazakov; Jack, Jones, Pickering

19 SSB terms depend only on g and the unified gaugino mass M universality conditions h = MC, m 2 M 2, b Mµ Very appealing! But too restrictive it leads to phenomenological problems: Charge and colour breaking vacua Incompatible with radiative electroweak breaking The lightest susy particle (LSP) is charged Possible to relax the universality condition to a sum-rule for the soft scalar masses better phenomenology. Kobayashi, Kubo, M.M., Zoupanos

20 All-loop RGI relations in the soft sector From reduction equations dc ijk dg = βijk C β g we assume the existence of a RGI surface on which h ijk = M dc(g)ijl d ln g holds too in all-orders. Then one can prove, that the following relations are RGI to all-loops M = M 0 β g g, h ijk = M 0 β ijk C, b ij = M 0 β ij µ, (m 2 ) i j = 1 2 M 0 2 µ dγi j dµ, (1) where M 0 is an arbitrary reference mass scale. If M 0 = m 3/2 we get exactly the anomaly mediated breaking terms

21 Soft scalar sum-rule for the finite case Finiteness implies C ijk = g n=0 ρ ijk (n) g2n h ijk = MC ijk + = Mρ ijk (0) g + O(g5 ) If lowest order coefficients ρ ijk (0) and (m2 ) i j satisfy diagonality relations ρ ipq(0) ρ jpq (0) δj i, (m 2 ) i j = m 2 j δi j for all p and q. We find the the following soft scalar-mass sum rule, also to all-loops for i, j, k with ρ ijk (0) 0, where (1) is the two-loop correction =0 for universal choice ( m 2 i + m 2 j + m 2 k )/MM = 1 + g2 16π 2 (2) + O(g 4 ) Kazakov et al; Jack, Jones et al; Yamada; Hisano, Shifman; Kobayashi, Kubo, Zoupanos Also satisfied in certain class of orbifold models, where massive states are organized into N = 4 supermultiples

22 Several aspects of Finite Models have been studied SU(5) Finite Models studied extensively Rabi et al; Kazakov et al; López-Mercader, Quirós et al; M.M, Kapetanakis, Zoupanos; etc One of the above coincides with a non-standard Calabi-Yau SU(5) E 8 Greene et al; Kapetanakis, M.M., Zoupanos Finite theory from compactified string model also exists (albeit not good phenomenology) Ibáñez Criteria for getting finite theories from branes N = 2 finiteness Models involving three generations Hanany, Strassler, Uranga Frere, Mezincescu and Yao Babu, Enkhbat, Gogoladze Some models with SU(N) k finite 3 generations, good phenomenology with SU(3) 3 Ma, M.M, Zoupanos Relation between commutative field theories and finiteness studied Jack and Jones Proof of conformal invariance in finite theories Kazakov

23 SU(5) Finite Models We study two models with SU(5) gauge group. The matter content is {5 + 5} + 24 The models are finite to all-loops in the dimensionful and dimensionless sector. In addition: The soft scalar masses obey a sum rule At the M GUT scale the gauge symmetry is broken and we are left with the MSSM At the same time finiteness is broken The two Higgs doublets of the MSSM should mostly be made out of a pair of Higgs {5 + 5} which couple to the third generation The difference between the two models is the way the Higgses couple to the 24 Kapetanakis, Mondragón, Zoupanos; Kazakov et al.

24 The superpotential which describes the two models takes the form W = 3 [ 1 2 gu i 10 i 10 i H i + gi d 10 i 5 i H i ] + g23 u H 4 i=1 +g d H 4 + g d H a=1 g f a H a 24 H a + gλ 3 (24)3 find isolated and non-degenerate solution to the finiteness conditions The unique solution implies discrete symmetries We will do a partial reduction, only third generation

25 The finiteness relations give at the M GUT scale Model A Model B g 2 t = 8 5 g2 g 2 t = 4 5 g2 g 2 b,τ = 6 5 g2 m 2 H u + 2m 2 10 = M2 m 2 H d + m m2 10 = M2 g 2 b,τ = 3 5 g2 m 2 H u + 2m 2 10 = M2 m 2 H d 2m 2 10 = M2 3 m m2 10 = 4M2 3 3 free parameters: M, m 2 5 and m free parameters: M, m 2 5

26 Phenomenology The gauge symmetry is broken below M GUT, and what remains are boundary conditions of the form C i = κ i g, h = MC and the sum rule at M GUT, below that is the MSSM. Fix the value of m τ tan β M top and m bot We assume a unique susy breaking scale The LSP is neutral The solutions should be compatible with radiative electroweak breaking No fast proton decay We also Allow 5% variation of the Yukawa couplings at GUT scale due to threshold corrections Include radiative corrections to bottom and tau, plus resummation (very important!) Estimate theoretical uncertainties

27 We look for the solutions that satisfy the following constraints: Right masses for top and bottom fact of life B physics observables fact of life FeynHiggs The lightest MSSM Higgs boson mass The SUSY spectrum FeynHiggs, FUT

28 TOP AND BOTTOM MASS M top [GeV] FUTA µ > 0 µ < 0 FUTB µ < 0 µ > 0 m bot (M Z ) FUTA FUTA µ > 0 µ < 0 FUTB FUTB M [GeV] M [GeV] FUTA: M top GeV Theoretical uncertainties 4% FUTB: M top GeV b and τ included, resummation done FUTB µ < 0 favoured

29 Experimental data We use the experimental values of M H to compare with our previous results (M H = GeV, 2007) and put extra constraints M exp H = 126 ± 2 ± 1 and = ± GeV theoretical, 1 GeV experimental M exp H We also use the BPO constraints BR(b sγ)sm/mssm : BRbsg < 0.27 BR(B u τν)sm/mssm : BRbtn 1.39 < 0.69 M Bs SM/MSSM : 0.97 ± 20 BR(B s µ + µ ) = (2.9 ± 1.4) 10 9 We can now restrict (partly) our boundary conditions on M

30 Higgs mass 134 FeynHiggs Mh [GeV] M [GeV] FUTB constrained by MHiggs 126 ± 3 (2013) and ± 3 GeV (2015) blue and red points satisfy B Physics constraints 2013 and 2016, 2016 with 2-loop mtop corrections Uncertainties ±3 GeV (FeynHiggs) Heinemeyer, M.M., Tracas, Zoupanos (2013) (2016)

31 S-SPECTRUM M h = ± 3.1 GeV M h = ± 2.1 GeV masses [GeV] 1000 masses [GeV] 1000 h H A H ± stop 1,2 sbot 1,2 gl. stau 1,2 cha 1,2 neu 1,2,3,4 h H A H ± stop 1,2 sbot 1,2 gl. stau 1,2 cha 1,2 neu 1,2,3,4 100 SUSY spectrum with B physics constraints 100 Challenging for LHC Heinemeyer, M.M., Zoupanos (2014)

32 Results When confronted with low-energy precision data only FUTB µ < 0 survives M top 173 GeV 4% m bot (M Z ) 2.8 GeV 8 % M Higgs 125 GeV (±3GeV ) tan β s-spectrum 500 GeV M exp top exp = (173.2 ± 0.9)GeV m exp bot (M Z ) = (2.83 ± 0.10)GeV M exp Higgs = ± 1 consistent with exp bounds In progress 3 families with discrete symmetry neutrino masses via R under way

33 Reduction of couplings in the MSSM The superpotential W = Y t H 2 Qt c + Y b H 1 Qb c + Y τ H 1 Lτ c + µh 1 H 2 with soft breaking terms, L SSB = φ m 2 φ φ φ + [ m 2 3 H 1H i=1 ] 1 2 M iλ i λ i + h.c + [h t H 2 Qt c + h b H 1 Qb c + h τ H 1 Lτ c + h.c.], then, reduction of couplings implies β Yt,b,τ = β g3 dy t,b,τ dg 3

34 Boundary conditions at the unification scale are given by Y 2 t g 2 3 4π = c 1 4π + c 2 Y 2 b g 2 3 4π = p 1 4π + p 2 ( g 2 ) 2 3 4π (2) ( g 2 ) 2 3 4π (3) Y τ not reduced, its reduction gives imaginary values c 2 and p 2 also found (long expressions not shown)

35 Soft breaking terms The reduction of couplings in the SSB sector gives the following boundary conditions at the unification scale Yt 2 = c 1 g3 2 + c 2g3 4 /(4π) and Y b 2 = p 1g3 2 + p 2g3 4 /(4π) h t,b = c t,b MY t,b, At the unification scale c t = c b = 1 and we recover M is unified gaugino mass m 2 H 2 + m 2 Q + m2 t c = M2, m 2 H 1 + m 2 Q + m2 b c = M2, coincide with anomaly mediated susy breaking

36 Corrections Same as with Yukawas the τ coupling cannot be reduced Possible to calculate the corrections coming from α 1, α 2, g τ to sum rule c t = N t D c b = N b D

37 Before corrections to the sum rule (2013,2014) 127 1e Mass [GeV] 1000 M A, M H, M H+- stop1,2 sbot1,2 stau1,2 neutralinos charginos gluino M Higgs M Higgs K τ SUSY spectrum and the Higgs mass Reduction of the third generation of quark masses at M GUT, before corrections to the sum rule and with one-loop corrections from m t to the Higgs mass

38 Corrections to sum rule Corrections to the sum-rule are scale dependent. N SR1 mh mq 2 + m2 t = c M2 3, D SR m 2 H 1 + m 2 Q + m2 b c = M2 3 N SR2 D SR, At the unification scale they are < 3 5%, at other scales they can be larger (< 17%)

39 Example, preliminary not complete 5000 Gauginos 4000 Stops Sbottoms Masses [GeV] Higgses Neutralinos Charginos 1000 Staus 0 Particles Example with sume rule at GeV, no corrections to sum-rule, satisfying phenomenological constraints

40 Results in Reduced MSSM Possible to have reduction of couplings in MSSM Up to now only attempted in SM or in GUTs Reduced system further constrained by phenomenology: compatible with quark masses with µ < 0 SUSY spectrum, large tan β Higgs mass GeV Heavy susy spectrum 500 GeV M LSP

41 Conclusions Reduction of couplings: powerful principle implies Gauge Yukawa Unification Finiteness, interesting and predictive principle reduces greatly the number of free parameters completely finite theories i.e. including the SSB terms, that satisfy the sum rule Confronting the SU(5) FUT models with low-energy precision data does distinguish among models FUTB favoured Possible to have reduction of couplings in MSSM (RMSSM) Heavy SUSY spectrum only solutions for µ < 0 compatible with quark masses large tan β s-spectrum starts above 500 GeV Higgs mass M h 125 GeV corrections to Yukawa couplings and sum rule calculated, depend on scale Detailed study of SUSY masses, Higgs decays, and three generations in progress Similar global results for FUT and RMSSM, but details differ