Classical mechanics is a branch of physics that describes the behavior of macroscopic objects, while quantum mechanics is a branch of physics that describes the behavior of subatomic particles. Classical mechanics is based on Newton's laws of motion, while quantum mechanics is based on the principles of probability and uncertainty.
While classical mechanics is very accurate for objects in our everyday lives, it breaks down when dealing with very small particles such as atoms and subatomic particles. Quantum mechanics was developed to accurately describe the behavior of these particles and has been proven to be extremely accurate in experiments.
Currently, there is no single theory that can fully explain both classical and quantum mechanics. However, efforts are being made to reconcile the two theories, such as the development of quantum field theory, which combines aspects of both classical and quantum mechanics.
In classical mechanics, the behavior of objects can be predicted with certainty. In quantum mechanics, however, the behavior of particles is described using probability distributions. This is due to the inherent uncertainty of measuring certain properties of particles, as described by Heisenberg's uncertainty principle.
Quantum mechanics has many practical applications, including the development of technologies such as transistors, lasers, and MRI machines. It also plays a crucial role in fields such as chemistry, material science, and cryptography.