The Higgs of the Higgs and the diphoton channel

Kannike, Kristjan; Pelaggi, Giulio Maria; Salvio, Alberto; Струмиа, Алессандро

doi:10.1007/jhep07(2016)101

Cited by 15 publications

(7 citation statements)

References 116 publications

(141 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We now follow the method of [52,54] to solve this equation and improve it, showing that it provides all the linearly independent solutions. We write the differential operator appearing in this equation, 16) in two equivalent ways…”

Section: S (T )mentioning

confidence: 99%

“…They lead to naturally flat inflationary potentials [3,[7][8][9][10][11][12][13] and dark matter candidates [10,[14][15][16][17] and represent an interesting framework to address the hierarchy problem [3,4,10,14,16,[18][19][20][21][22][23][24][25]. This no-scale principle has also the virtue of being predictive as only dimension-four operators are allowed in the classical Lagrangian, which can be viewed as a strong constraint on the allowed free parameters.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Inflationary perturbations in no-scale theories

Salvio

2017

Eur. Phys. J. C

Self Cite

View full text Add to dashboard Cite

We study the inflationary perturbations in general (classically) scale-invariant theories. Such scenario is motivated by the hierarchy problem and provides natural inflationary potentials and dark matter candidates. We analyse in detail all sectors (the scalar, vector and tensor perturbations) giving general formulae for the potentially observable power spectra, as well as for the curvature spectral index n s and the tensor-to-scalar ratio r . We show that the conserved Hamiltonian for all perturbations does not feature negative energies even in the presence of the Weyl-squared term if the appropriate quantisation is performed and argue that this term does not lead to phenomenological problems at least in some relevant setups. The general formulae are then applied to a concrete no-scale model, which includes the Higgs and a scalar, "the planckion", whose vacuum expectation value generates the Planck mass. Inflation can be triggered by a combination of the planckion and the Starobinsky scalar and we show that no tension with observations is present even in the case of pure planckion inflation, if the coefficient of the Weyl-squared term is large enough. In general, even quadratic inflation is allowed in this case. Moreover, the Weyl-squared term leads to an isocurvature mode, which currently satisfies the observational bounds, but it may be detectable with future experiments.

show abstract

Section: S (T )mentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Inflationary perturbations in no-scale theories

Salvio

2017

Eur. Phys. J. C

Self Cite

View full text Add to dashboard Cite

show abstract

“…Scale-invariant theories present several very interesting aspects in this perspective as they do not contain any fundamental scale in the action at the classical level but dynamically leads to scalegenesis via quantum corrections [1][2][3][4][5][6]. Some of the salient features that are manifest from such investigations over the past four decades lead to naturally flat inflationary potentials [3,[7][8][9][10][11][12][13] and provide mechanisms of particle production or dark matter candidates [10,[14][15][16][17], possess a motivating framework to address the gauge hierarchy problem, [3,4,10,14,16,[18][19][20][21][22][23][24][25] and also leads to strong first-order phase transitions in early universe. In turn, these can produce large amplitude gravitational wave (GW) signals, mainly due to the dominant nature of thermal corrections in the absence of tree-level mass terms [26][27][28][29][30][31][32][33].…”

Section: Introductionmentioning

confidence: 99%

Inflation and primordial gravitational waves in scale-invariant quadratic gravity

Ghoshal¹,

Mukherjee²,

Rinaldi³

2022

Preprint

View full text Add to dashboard Cite

In scale-invariant models of fundamental physics all mass scales are generated via spontaneous symmetry breaking. In this work, we study inflation in scale-invariant quadratic gravity, in which the Planck mass is generated classically by a scalar field, which evolves from an unstable fixed point to a stable one thus breaking scale-invariance. We investigate the dynamics by means of dynamical system standard techniques. By computing the spectral indices and comparing them with data, we put some constraints on the three dimensionless parameters of the theory. We show that certain regions of the parameter space will be within the range of future CMB missions like CMB-S4, LITBird and STPol. The second half of the paper is dedicated to the analysis of inflationary first-order tensor perturbations and the calculation of the power spectrum of the gravitational waves. We comment on our results and compare them with the ones of mixed Starobinsky-Higgs inflation.

show abstract

“…In BSM scenarios, assuming no scale is fundamental in nature and all mass scales being generated dynamically have been explored extensively in the literature [56][57][58][59][60][61]. In context of non-minimally coupling to gravity, they provide naturally flat inflationary potentials [58,[62][63][64][65][66][67][68] and dark matter candidates [65,[69][70][71][72][73], and also leads to very strong first-order phase transitions via supercooling in early universe and therefore the possibility of high amplitude detectable gravitational wave (GW) signals mainly due to dominance of thermal corrections in absence of tree-level mass terms [74][75][76][77][78][79][80][81] and have always been seen as direction of model-building for the hierarchy problem in the Standard Model of particle physics [55,58,59,65,69,71,[82][83][84][85][86][87]. See Refs.…”

Section: Introductionmentioning

confidence: 99%

Radiative Plateau Inflation with Conformal Invariance: Dynamical Generation of Electroweak and Seesaw Scales

Ghoshal¹,

Okada²,

Paul³

2022

Preprint

View full text Add to dashboard Cite

We investigate in scale-invariant B −L scenario where the Standard Model (SM) is supplemented with a dark scalar φ associated with gauge & Yukawa interactions, described by the couplings g BL and y respectively, leading to radiative plateau inflation at scale φ = M in the ultraviolet (UV), while dynamically generating the Electroweak and Seesaw scales á lá Coleman-Weinberg in the infrared (IR). This is particularly achieved implementing threshold correction at an energy scale µ T arising due to the presence of vector-like fermions. We show that implementing the inflationary observables makes the couplings solely dependent on the plateau scale or inflection-point scale M , leaving us with only two independent parameters M and µ T . Within the theoretically consistent parameter space regions defined by m Z BL > 850 GeV, from the assumption of independent evolution of the dark sector couplings from the SM couplings and M < 5.67 times the Planck scale (M P ) required for the realisation of inflationary plateau-like behaviour of the potential around φ = M , we identify the parameter space that is excluded by current LHC results involving searches for the heavy Z BL boson. For typical benchmark points in the viable parameter regions, we estimate the reheating temperature to be ∼ O(T eV ) thus consistent with the standard Big Bang Nucleosynthesis (BBN) constraints. For typical benchmark points (M = 5.67, 1, 0.1 M P ) we predict the scales of inflation to be H inf

show abstract

The Higgs of the Higgs and the diphoton channel

Cited by 15 publications

References 116 publications

Inflationary perturbations in no-scale theories

Inflationary perturbations in no-scale theories

Inflation and primordial gravitational waves in scale-invariant quadratic gravity

Radiative Plateau Inflation with Conformal Invariance: Dynamical Generation of Electroweak and Seesaw Scales

Contact Info

Product

Resources

About