Baryonic Matter
Baryonic matter comprises all ordinary matter in the universe composed of atoms and molecules, including stars, planets, gas clouds, and dust. It is the only form of matter that interacts electromagnetically and is directly observable through light emission and absorption. According to current cosmological models, baryonic matter represents approximately 5% of the universe’s total mass-energy content, while dark-matter accounts for roughly 27% and dark energy makes up the remaining 68%.
In the context of galaxy-clusters, the distribution and quantity of baryonic matter are critical for testing gravitational theories. Recent observations suggest that the amount of baryonic matter in these clusters may be underestimated, presenting challenges to current dark matter theory. This discrepancy highlights the complexity of mapping visible matter against the inferred gravitational effects attributed to dark matter.
The study of baryonic matter in large-scale structures remains a focal point for cosmologists seeking to refine model parameters. Recent data from the milky-way further complicates the landscape:
- New rotation curve data challenges established theories regarding the ratio of dark to normal matter in our galaxy.
- Traditional estimates posited that the Milky Way contains about ten times more dark matter than normal matter, with distribution inferred from flat rotation curves.
- Recent findings defy standard explanations, impacting both dark-matter paradigms and modified-newtonian-dynamics-mond.
- See Milky Way Rotation Data Challenges Dark Matter and Modified Gravity for detailed analysis.
References
- Hossenfelder, S. “Headache: New Milky Way Data Just Defies Explanation.” Milky Way Rotation Data Challenges Dark Matter and Modified Gravity.