Interesting simulation of a spiral galaxy evolution.

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Discussion Overview

The discussion revolves around a simulation of spiral galaxy evolution, focusing on the visual representation of rotation, the development of an axis of rotation, and the implications of gravitational acceleration in galaxy formation. Participants explore both the characteristics of the simulation and its relation to real-world phenomena.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants note the visible change in rotation direction within the simulation, questioning whether this is a real phenomenon or an artifact of the simulation.
  • One participant observes that a clear axis of rotation develops in the simulation, prompting inquiries about whether this is typical behavior or influenced by initial conditions.
  • Another participant mentions the absence of jets in the early formation phase depicted in the simulation, suggesting that gravitational acceleration may not be accurately represented and proposing a simulation with limited gravitational acceleration.
  • A participant expresses curiosity about the creation of the simulation, asking whether it was a custom program or an existing one.

Areas of Agreement / Disagreement

The discussion contains multiple competing views regarding the implications of the simulation's features, such as the direction of rotation and the presence of jets, and remains unresolved on these points.

Contextual Notes

Participants express uncertainty about the relationship between the simulation's characteristics and actual observational evidence, particularly concerning the direction of rotation and the development of the axis of rotation.

Who May Find This Useful

Individuals interested in astrophysics, galaxy formation, and simulation methodologies may find this discussion relevant.

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VERY cool. Thanks for posting.
 
Interesting.

at about 0:45 counterclockwise rotation is clearly visible. by 1:30 the direction of rotation is clockwise. Between 1:05 and 1:30 direction of rotation seems to be dependent on the distance from the center.

I'm curious if this sort of change in the direction of rotation is a real phenomena or just a feature of this simulation.

Does anyone know of any observational evidence one way or the other?
 
Also interesting is after about 20 seconds a clear axis of rotation develops and stays pointing in the same direction even though the mass of the galaxy changes many times. Does that seem typical or must it be from initial conditions of the initial matter cloud? I assume we are viewing from some point with fixed orientation (what the hell does that mean)?

Thanks for any help!
 
No jets. Early formation should produce jets.

I'm assuming from that model that gravitational acceleration wasn't limited, it would be nice to see a simulation where it was. /1+limit+R² (there is no observation that shows acceleration -> infinity as r->0, it's only an assumption, if you accept frame dragging then the assumption must be incorrect anyway)
 
Do you know how they created the stimulation? Was it a custom program or one already made?
 

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