Double Klondike are usually agreed for competitive play: Double Klondike Double Klondike is a variant on the playing card game popularly known either as Solitaire or Snap-Up Patience, specifically a variant on the most well-known version of the game, Klondike. It is sometimes referred to simply as "Double Solitaire". Triple Solitaire, Quadruple Solitaire, etc. is also possible and is played. It is not to be confused with the single-player game of Gargantua which is also known as Double Klondike. As the name suggests, Double Klondike is a two-player game, and is played with two full packs of playing cards, minus the Jokers;
Double beta decay or double beta decay are predicted to be very long; hence, quadruple beta decay is unlikely to be realized. The eight candidate nuclei for quadruple beta decay include Zr, Xe, and Nd capable of quadruple beta-minus decay, and Xe, Ba, Gd, and Dy capable of quadruple beta-plus decay or electron capture. In theory, quadruple beta decay may be experimentally observable in three of these nuclei, with the most promising candidate being Nd. Double beta decay In nuclear physics, double beta decay is a type of radioactive decay in which two neutrons are simultaneously transformed into two protons, or vice versa,