CMB constraints on DHOST theories

Abstract

We put constraints on the degenerate higher-order scalar-tensor (DHOST) theories using the Planck 2018 likelihoods. In our previous paper, we developed a Boltzmann solver incorporating the effective field theory parameterised by the six time-dependent functions, ${\alpha }_i$ $(i=\mathrm{B},\mathrm{K},\mathrm{T},\mathrm{M},\mathrm{H})$ and ${\beta }_1$, which can describe the DHOST theories. Using the Markov-Chain Monte-Carlo method with our Boltzmann solver, we find the viable parameter region of the model parameters characterising the DHOST theories and the other standard cosmological parameters. First, we consider a simple model with ${\alpha }_{\mathrm{K}}={\Omega }_{\mathrm{DE}}(t)/{\Omega }_{\mathrm{DE}}(t_0)$, ${\alpha }_{\mathrm{B}}={\alpha }_{\mathrm{T}}={\alpha }_{\mathrm{M}}={\alpha }_{\mathrm{H}}=0$ and ${\beta }_1={\beta }_{1,0}{\Omega }_{\mathrm{DE}}(t)/{\Omega }_{\mathrm{DE}}(t_0)$ in the $\Lambda$CDM background where $t_0$ is the present time and obtain ${\beta }_{1,0}=0.032_{-0.016}^{+0.013}$ (68\% c.l.). Next, we focus on another theory given by ${\mathcal{L}}_{\mathrm{DHOST}}=X+c_{3}X\square \varphi /{\Lambda }^3+(M_{\mathrm{pl}}^2/2+c_4{X}^2/{\Lambda }^6)R+48c_4^2{X}^2/(M_{\mathrm{pl}}^2{\Lambda }^{12}+2c_4{\Lambda }^6{X}^2){\varphi }^{\mu }{\varphi }_{\mu \rho }{\varphi }^{\rho \nu }{\varphi }_{\nu }$ with $X:={\partial }_{\mu }\varphi {\partial }^{\mu }\varphi$ and two positive constant parameters, $c_3$ and $c_4$. In this model, we consistently treat the background and the perturbations, and obtain $c_3=1.59_{-0.28}^{+0.26}$ and the upper bound on $c_4$, $c_4<0.0088$ (68\% c.l.).

10 pages, 4 figures, 1 table; v2 : typos corrected

References in corpus (14)

• GW170817: Observation of Gravitational Waves from a Binary Neutron Star Inspiral
• Multi-messenger Observations of a Binary Neutron Star Merger
• Gravitational Waves and Gamma-rays from a Binary Neutron Star Merger: GW170817 and GRB 170817A
• Healthy theories beyond Horndeski
• Horndeski theory and beyond: a review
• Exploring gravitational theories beyond Horndeski
• Maximal freedom at minimum cost: linear large-scale structure in general modifications of gravity
• A unifying description of dark energy
• Vainshtein regime in Scalar-Tensor gravity: constraints on DHOST theories
• Towards Strong Field Tests of Beyond Horndeski Gravity Theories
• Weakening Gravity on Redshift-Survey Scales with Kinetic Matter Mixing
• Observational signatures of the theories beyond Horndeski
• On the screening mechanism in DHOST theories evading gravitational wave constraints
• Stellar Pulsations in Beyond Horndeski Gravity Theories

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