Thread: Quasars formation and evolution

Please find here a paper on quasar formation and evolution: http://fr.calameo.com/books/000145333477ac4808aec
Your comments are welcome.

The manuscript was updated as of the 1st of February 2010 to account for the following observation: The half-life of quasars was estimated at 1.33 billion years which is close the potassium-40 to argon half-life. Note that potassium-40 half-life is the preferred method for the datation of magmatic rocks.

To be more accurate 1.3 Gyr is the half-live of potassium-40 which can decay into Ca, and isotopes of argon..