The paper by William Giare reviews the implications of considering new physics in light of the Hubble tension for inflation. The author argues that constraints on inflationary parameters, such as the spectral index \( n_s \), depend on the cosmological framework. To avoid broadening uncertainties from marginalizing over additional parameters, Giare analyzes what happens if a physical theory can fix extra parameters to non-standard values. Focusing on the dark energy equation of state \( w \) and the effective number of relativistic species \( N_{\text{eff}} \), he confirms that theories fixing \( w \approx -1.2 \) or \( N_{\text{eff}} \approx 3.9 \) produce \( H_0 \) values consistent with the local distance ladder estimate. While fixing \( w \) does not significantly affect inflation, fixing \( N_{\text{eff}} \) leads to a shift towards \( n_s \approx 1 \). Both scenarios are strongly disfavored compared to the standard \(\Lambda\)CDM model. However, models with \( N_{\text{eff}} \approx 3.3 - 3.4 \) could reduce the \( H_0 \) tension to \(\sim 3\sigma\) while being moderately disfavored. Giare then focuses on Early Dark Energy (EDE), arguing that a small fraction of EDE could require a similar shift in perspective on inflation. A full joint analysis of EDE and Starobinsky inflation shows that the two models cannot coexist when the EDE fraction exceeds \(\sim 6\%\). The paper concludes by discussing the implications of early-time and late-time new physics for inflation, emphasizing the need to carefully consider the constraints on inflationary parameters when introducing new physics.The paper by William Giare reviews the implications of considering new physics in light of the Hubble tension for inflation. The author argues that constraints on inflationary parameters, such as the spectral index \( n_s \), depend on the cosmological framework. To avoid broadening uncertainties from marginalizing over additional parameters, Giare analyzes what happens if a physical theory can fix extra parameters to non-standard values. Focusing on the dark energy equation of state \( w \) and the effective number of relativistic species \( N_{\text{eff}} \), he confirms that theories fixing \( w \approx -1.2 \) or \( N_{\text{eff}} \approx 3.9 \) produce \( H_0 \) values consistent with the local distance ladder estimate. While fixing \( w \) does not significantly affect inflation, fixing \( N_{\text{eff}} \) leads to a shift towards \( n_s \approx 1 \). Both scenarios are strongly disfavored compared to the standard \(\Lambda\)CDM model. However, models with \( N_{\text{eff}} \approx 3.3 - 3.4 \) could reduce the \( H_0 \) tension to \(\sim 3\sigma\) while being moderately disfavored. Giare then focuses on Early Dark Energy (EDE), arguing that a small fraction of EDE could require a similar shift in perspective on inflation. A full joint analysis of EDE and Starobinsky inflation shows that the two models cannot coexist when the EDE fraction exceeds \(\sim 6\%\). The paper concludes by discussing the implications of early-time and late-time new physics for inflation, emphasizing the need to carefully consider the constraints on inflationary parameters when introducing new physics.