Asymptotic safety in the dark

Eichhorn, Astrid; Held, Aaron; Griend, Peter Vander

doi:10.1007/jhep08(2018)147

Cited by 12 publications

(16 citation statements)

References 99 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The separation of scales allow us to investigate a condensematter-like unification of the SM couplings before having to consider the gravitational corrections. The interplay with gravity has been investigated in several recent works [34][35][36][37][38] and it will not be considered here. Differently from the usual grand unified scenarios [39] in which only the gauge couplings unify because of their embedding into a larger group structure and then they eventually become free, in the present scenario we have that Yukawa and scalar self couplings are intimately linked because of the safe dynamics with their high energy behavior tamed by the presence of an interacting fixed point.…”

Section: Introductionmentioning

confidence: 99%

Asymptotically safe Pati-Salam theory

2018

View full text Add to dashboard Cite

We provide an asymptotically safe Pati-Salam embedding of the standard model. Safety is achieved by adding to the theory gauged vectorlike fermions and by employing recently developed large number-offlavor techniques and results. We show that the gauge, scalar quartic and Yukawa couplings achieve an interacting ultraviolet fixed point below the Planck scale. The minimal model is a relevant example of a standard model extension in which unification of all type of couplings occurs because of a dynamical principle, i.e., the presence of an ultraviolet fixed point. This extension differs from the usual grand unified theories scenario in which only gauge couplings unify and become free with the remaining couplings left unsafe. We find renormalization group flow solutions that match the standard model couplings values at low energies allowing for realistic safe extensions of the standard model.

show abstract

Section: Introductionmentioning

confidence: 99%

Asymptotically safe Pati-Salam theory

2018

View full text Add to dashboard Cite

show abstract

“…In the last section, we have explained that fixed points can also be interacting, which generalises asymptotic freedom to asymptotic safety. Asymptotic safety can show up in a perturbative way as in the Litim-Sannino model [66,67] or in a non-perturbative way, as in quantum gravity [69], gauge theories at large N f [70][71][72][73][74][75] or other matter models [76]. It is very challenging to prove the existence of a non-perturbative fixed point and thus we just state that these theories might be asymptotically safe.…”

Section: Choice Of the Bare Actionmentioning

confidence: 99%

Lecture notes: Functional Renormalisation Group and Asymptotically Safe Quantum Gravity

Reichert¹

2020

Proceedings of XV Modave Summer School in Mathematical Physics — PoS(Modave2019)

View full text Add to dashboard Cite

These lecture notes give an introduction to the functional renormalisation group and asymptotically safe quantum gravity. We cover the basics of generating functionals in quantum field theories and derive the Wetterich equation. The anharmonic oscillator is presented as a simple example and compared to perturbation theory with resummation methods. A special focus is set on the implementation of symmetries in the functional renormalisation group. The second half of these notes is dedicated to quantum gravity, explaining the failure of perturbative gravity and how these issues are addressed in the non-perturbative approach. After detailing the implementation of the diffeomorphism symmetry, we present a simple computation in the Einstein-Hilbert truncation and give a short outlook on the state-of-the-art in the field. These notes are based on lectures given at the XV Modave Summer School in Mathematical Physics.

show abstract

Section: The Higgs Potential and New Physicsmentioning

confidence: 99%

“…We will argue that the declining of the Higgs quartic coupling towards the UV is only true for fermions coupled via a Yukawa interaction yHtt. It has recently been suggested [39], that the fundamentally different vertex structure of fermions coupled via a Higgsportal coupling of the form L Higgs-portal ∼λ hψ H † Hψψ (1) could lead to a regime in which dark fermions, with sufficiently light massm ψ , in fact delay the onset of the Higgs-instability scale. This approach is different from other scenarios discussed in the literature with additional right-handed neutrinos where the stabilizing effect was caused by UV boundary conditions governed by highscale supersymmetry [40].…”

Section: The Higgs Potential and New Physicsmentioning

confidence: 99%

See 1 more Smart Citation

Higgs stability-bound and fermionic dark matter

Held¹,

Sondenheimer

2019

J. High Energ. Phys.

Self Cite

View full text Add to dashboard Cite

Higgs-portal interactions of fermionic dark matter -in contrast to fermions coupled via Yukawa interactions -can have a stabilizing effect on the standard-model Higgs potential. A non-perturbative renormalization-group analysis reveals that, similar to higher-order operators in the Higgs potential itself, the fermionic portal coupling can increase the metastability scale by only about one order of magnitude. Furthermore, this regime of very weakly coupled dark matter is in conflict with relic-density constraints. Conversely, fermionic dark matter with the right relic abundance requires either a low cutoff scale of the effective field theory or a strongly interacting scalar sector. This results in a triviality problem in the scalar sector which persists at the non-perturbative level. The corresponding breakdown of the effective field theory suggests a larger dark sector to be present not too far above the dark-fermion mass-scale. I. THE HIGGS POTENTIAL AND NEW PHYSICSThe most surprising result obtained at the Large Hadron Collider might be, that the masses and couplings conspire to render the standard model consistent up to very high energy scales, possibly even all the way up to the Planck scale [1][2][3][4][5]. It is a delicate balance between the running of gauge couplings, Yukawa couplings and the Higgs potential that results in this unexpected experimental result. Although this so-called "desert" disfavors new degrees of freedom to be discovered any time soon, it should maybe not be taken as discouragement. Experimental evidence suggests that our knowledge of the Universe is more complete than we might have hoped for. The vast other parts of parameter space, in which the standard model as an effective field theory (EFT) could in principle be realized, results either in an instability of the scalar potential or in a sub-Planckian triviality problem. Both of these could be interpreted as a clear sign for a breakdown of the standard model and an associated new physics scale.Focusing on the central measurement values [6], the standard model as an EFT is potentially valid up to Λ (SM) EFT ≈ 10 41 GeV. At this scale, the theory reaches a U (1) Landau-pole in perturbation theory [7], reflected in a triviality problem at the non-perturbative level [8][9][10]. This would suggest that the next energy scale that theorists should be concerned about is the Planck scale, at which a joint theory of gravity and matter becomes necessary, see e.g., [11][12][13][14][15][16][17]. On the other hand, the standard model Higgs-potential, assuming that the current central values of measured mass and coupling parameters were exact, develops a metastability. The energy scale associated with this metastability is Λ (SM) meta ≈ 10 10 − 10 11 GeV [1-5, 18]. Much interesting physics can be associated with this metastability [19][20][21][22][23], and the metastable * a.held@thphys.uni-heidelberg.de † rene.sondenheimer@uni-jena.de electroweak vacuum could be long-lived enough to allow for the current age of the universe [24][25][26][27][28][...

show abstract

Asymptotic safety in the dark

Cited by 12 publications

References 99 publications

Asymptotically safe Pati-Salam theory

Asymptotically safe Pati-Salam theory

Lecture notes: Functional Renormalisation Group and Asymptotically Safe Quantum Gravity

Higgs stability-bound and fermionic dark matter

Contact Info

Product

Resources

About