Standard model Higgs inflation supplemented by minimal dark matter

Renormalization group analysis with the present measurements of the top quark mass <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:msub><a:mi>m</a:mi><a:mi>t</a:mi></a:msub><a:mo>=</a:mo><a:mn>172.69</a:mn><a:mo>±</a:mo><a:mn>0.30</a:mn><a:mtext> </a:mtext><a:mtext> </a:mtext><a:mi>GeV</a:mi></a:math> [1] indicates that the Standard Model (SM) Higgs potential becomes unstable at energy scales <c:math xmlns:c="http://www.w3.org/1998/Math/MathML" display="inline"><c:mo>∼</c:mo><c:msup><c:mn>10</c:mn><c:mn>10</c:mn></c:msup><c:mtext> </c:mtext><c:mtext> </c:mtext><c:mi>GeV</c:mi></c:math>. This may be interpreted as hinting at new particles at high energy. The minimal extension of the SM that can avoid this instability while leaving the SM Higgs as the sole scalar particle of the theory is obtained by adding suitable fermions to the SM. These fermions are good dark matter candidates and the model is known as the minimal dark matter model. We revisit the inflationary scenario based on the minimal dark matter model, taking into account updated parameter constraints and recent understanding of reheating dynamics. We explore the model with different values of the right-handed neutrino mass and find that the cosmological prediction is insensitive to such details. We obtained a spectral index of the cosmic microwave background <e:math xmlns:e="http://www.w3.org/1998/Math/MathML" display="inline"><e:msub><e:mi>n</e:mi><e:mi>s</e:mi></e:msub><e:mo>=</e:mo><e:mn>0.9672</e:mn></e:math> and a tensor-to-scalar ratio <g:math xmlns:g="http://www.w3.org/1998/Math/MathML" display="inline"><g:mi>r</g:mi><g:mo>=</g:mo><g:mn>0.0031</g:mn></g:math> as a robust prediction of this scenario. Published by the American Physical Society 2024