FTP, identify this concept defined as the violation of the two namesake properties resulting in the abundance of X-rays in the universe.
First noticed when decaying K mesons broke theory and became two pi mesons instead of three, physicists have not been able to agree on a satisfactory explanation for it yet.  Some have postulated a new "superweak" force to explain it, others believe in the Kobayashi-Maskawa model, which attributes it to certain quantum effects in the weak force between quarks.  First identified by James Cronin and Val Fitch, it is thought to have led to the current matter-antimatter ratio in the universe.  FTP, identify this concept defined as the violation of the two namesake properties resulting in the abundance of X-rays in the universe.
First noticed when decaying K mesons broke theory and became two pi mesons instead of three, physicists have not been able to agree on a satisfactory explanation for it yet.  
CP violation or charge conjugation-parity violation