quantum state

American  

noun

Physics.

1. the condition in which a physical system exists, usually described by a wave function or a set of quantum numbers.

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quantum state British  

noun

1. physics a state of a system characterized by a set of quantum numbers and represented by an eigenfunction. The energy of each state is precise within the limits imposed by the uncertainty principle but may be changed by applying a field of force. States that have the same energy are called degenerate See also energy level

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quantum state Scientific  

1. A description in quantum mechanics of a physical system or part of a physical system. Different quantum states for a physical system show discrete differences in the value of the variables used to define the state. For example, the spin of an isolated electron can take on one of only two values; there are no other quantum states available for the electron and no intermediate values, since spin is quantized. The quantum state is sometimes described by a set of quantum numbers that pick out the appropriate values for describing the state.

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Etymology

Origin of quantum state

First recorded in 1920–25

Example Sentences

Entanglement allows multiple qubits to share a single quantum state and act as one coordinated system, which is essential for powerful quantum computers.

From Science Daily • Apr. 13, 2026

For the first time, they were able to determine in real time and with a single measurement whether the combined quantum state formed by the two Majorana modes was even or odd.

From Science Daily • Feb. 16, 2026

Qubits are extremely fragile, and the slightest changes in the environment can disrupt their delicate quantum state.

From Barron's • Jan. 6, 2026

The faster the gate speed, the more computations can be performed before qubits fall out of their quantum state in a process called decoherence.

From MarketWatch • Oct. 25, 2025

In particular, no two electrons of the same quantum state can be forced into the same spot.

From "Zero: The Biography of a Dangerous Idea" by Charles Seife