> The answer is most likely MOND + dark matter. Here[0] is a toy model experiment to demonstrate that neither Dark Matter nor MOND are necessary to explain spi

> The answer is most likely MOND + dark matter. Here[0] is a toy model experiment to demonstrate that neither Dark Matter nor MOND are necessary to explain spiral galaxy rotation curves, which coincidentally is the original purpose Dark Matter was postulated to explain. Dark Matter has since been fingered to explain other phenomena since, but it is not commonly known or accepted that galaxy rotation curves no longer needs Dark Matter (or MOND, for that matter). [0] https://m.youtube.com/watch?v=PL0ewiwqoTw&t=9m40s https://m.youtube.com/watch?v=PL0ewiwqoTw&t=9m40s