The lives of galaxies can be extended if their supermassive black holes that provide them with "hearts and lungs" to support their "breathing" and prevent them from growing too large.
That is the suggestion of new research indicating the universe would have aged much faster and would today be filled with "zombie" galaxies containing dead or dying stars were it not for the supermassive black holes thought to sit at the hearts of all large galaxies. The astrophysicists behind the findings compare jets of gas and radiation that supermassive black holes blow from their poles to the airways that feed our lungs.
