Discussion Overview
The discussion revolves around the classification of galaxies in the context of the three-body problem, particularly considering the role of dark matter. Participants explore whether galaxies can be treated as a three-body problem or if they are better understood as many-body systems, while also discussing the complexities of solving the three-body problem in general.
Discussion Character
- Debate/contested
- Technical explanation
- Mathematical reasoning
Main Points Raised
- Some participants argue that three galaxies held together by dark matter do not constitute a three-body problem due to their loose structure, suggesting that the Sun, Earth, and Moon serve as a better example.
- Others propose that if galaxies are sufficiently distant from each other, their relative motions could be analyzed as a three-body problem, provided there are no other galaxies or dark matter concentrations nearby.
- A participant mentions that galaxies might be treated as fluid dynamical problems due to their many-body nature, drawing an analogy between gravity and van der Waals forces.
- Historical approaches to modeling galaxies included analytical methods, but current practices favor numerical simulations, as highlighted by references to the Toomre brothers' work.
- One participant presents a hypothetical scenario involving a satellite orbiting Earth, discussing the forces acting on it and proposing a simplified equation related to the three-body problem.
- There is a discussion about the existence of solutions to the three-body problem, with some participants asserting that numerical methods are the only viable approach, while others question whether an analytical solution might still be possible.
- Concerns are raised regarding the accuracy of numerical integrations due to truncation and round-off errors, contrasting them with the desire for analytical solutions that avoid such issues.
Areas of Agreement / Disagreement
Participants express differing views on whether galaxies can be treated as a three-body problem, with no consensus reached. There are also varying opinions on the nature of solutions to the three-body problem, particularly regarding the feasibility of analytical versus numerical methods.
Contextual Notes
Some discussions reference the limitations of analytical solutions in the context of chaotic systems and the need for precise definitions of perturbations, indicating that the discussion is constrained by these unresolved complexities.