Quantum Mechanics

We have learnt that there is a wave associated with every particle. This is not evident for macroscopic particles like a bullet or an elephant because the wavelength is extremely small. The wave nature becomes important when dealing with microscopic particles like an electron for which the wavelength can be of the order of $1 \, \AA$. We have also learnt that this wave $\psi(x,t)$ may be interpreted as the probability amplitude and this wave is often referred to as the wavefunction. The laws governing the evolution of the wavefunction and it interpretation are referred to as Quantum Mechanics.