Definition

1. Noun:
   • (Quantum Mechanics): A fundamental principle stating that certain pairs of physical properties, such as position and momentum or energy and time, cannot both be measured with perfect precision simultaneously. The more accurately one property is known, the less accurately the other can be known.

Usage

• The uncertainty principle is a cornerstone of quantum mechanics, not a limitation of measurement instruments but a fundamental property of nature.
• It is used to describe the inherent limits in the precision of knowledge about a quantum system.

Examples

• Noun:
  • Heisenberg's uncertainty principle places a fundamental limit on what we can know about a particle's behavior.
  • The uncertainty principle implies that a vacuum is not truly empty but filled with fluctuating energy.

Advanced Usage

• "Heisenberg uncertainty principle": The most common specific name for this concept, formulated by Werner Heisenberg.
  • The Heisenberg uncertainty principle is often explained using the analogy of trying to measure an electron's position with light.
• "The uncertainty principle applies to...": Used to specify the conjugate variables involved.
  • The uncertainty principle applies to other pairs of observables, like angular momentum components.

Variants and Related Words

• Indeterminacy principle: A less common synonym for the uncertainty principle.
• Quantum indeterminacy: The general concept that certain properties lack definite values until measured, of which the uncertainty principle is a key part.

Synonyms

• Heisenberg principle: A direct synonym referencing its discoverer.
• Principle of indeterminacy: A synonym emphasizing the inherent lack of determinacy.

Related Phrases

• Uncertainty relation: A more technical term referring to the mathematical inequality (e.g., ΔxΔp ≥ ħ/2) that quantifies the principle.
  • The uncertainty relation sets a minimum for the product of the uncertainties.

Related Concepts

• Wave-particle duality: A complementary quantum concept often discussed alongside the uncertainty principle.
• Quantum fluctuation: A phenomenon directly connected to the energy-time uncertainty relation.

Noun

1. (quantum theory) the theory that it is impossible to measure both energy and time (or position and momentum) completely accurately at the same time