Heisenberg Uncertainty Principle is very important aspect of quantum mechanics. It it even regarded the foundation of quantum mechanics. According to Heisenberg Uncertainty Principle, “The precise measurement of position and momentum of a high speed particle simultaneously is not possible.” This means when we measure the position of a particle, the momentum cannot be determined precisely and vice versa. There exists at least a error h/2π.
While measuring the velocity and position of an electron at the same time, if we measure its position, then its exact velocity cannot be determined. If we measure its velocity, its exact position cannot be determined.
If x has uncertainty Δx and the momentum has uncertainty Δp, then uncertainty is calculated by the inequality below.
Δx × Δp ≥ h/2π…….(i)
This is the Heisenberg’s Uncertainty principle.
Those pair of physical quantities in which this principle holds true are called canonically conjugate variables. Some other canonically conjugate pairs are:
- Energy and time
- Angular momentum and orientation
- Magnetic potential and electric current
This principle gives mathematical evidence for why an electron never jumps to the nucleus thereby explaining the stability of atom.