There is a matter-antimatter imbalance in the universe, and our current theory of particle physics, the standard model, doesn't explain this imbalance.
Symmetry invariance plays a crucial role in understanding the properties and behavior of particles, fields, and the fundamental forces of nature. The charge parity symmetry, or CP symmetry, is one such symmetry fundamental to particle physics.
According to the CP symmetry, the laws of physics are conserved, meaning that they remain the same if the charges of all particles are reversed, and their spatial position or coordinates are inverted (parity reversal).
In other words, CP symmetry suggests that the behavior of particles and antiparticles should be identical under these transformations. However, the overwhelming amount of matter compared to antimatter in the universe suggests a violation of this.
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