We analyzed a sample of 175 disk galaxies from the SPARC database to study how dark matter influences their rotation curves. For each galaxy, we compared the observed rotation speeds with the contributions expected from stars, gas, and bulges. To test this, we fitted two different models: one that relies only on visible matter, and another that allows for additional gravitational effects beyond what normal matter can explain. To judge which model works better, we used statistical tools such as AIC and BIC, which measure how well a model fits the data. By ranking galaxies according to the difference in AIC, we were able to identify the cases where visible matter alone cannot account for the observed rotation. In most situations, these differences are linked to the presence of dark matter, but they could also hint at more exotic possibilities, such as effects from extra dimensions. Overall, our study highlights a set of galaxies where additional gravitational effects are most evident. These results offer new insight into how mass is distributed in disk galaxies and point to promising targets for future investigations of dark matter and related phenomena.
Diksha et al. (Mon,) studied this question.