Definition

Noun: A hypothetical elementary particle that is the quantum of gravitational force and a gauge boson that mediates gravitational interactions between particles. It is postulated in quantum field theory but has not been experimentally observed.

Usage

The word "graviton" is used exclusively as a noun in theoretical physics to discuss the quantum carrier of gravity. It is a count noun (e.g., a graviton, gravitons).

Examples

• According to the theory, gravitons would be exchanged between masses, analogous to how photons mediate the electromagnetic force.
• Detecting a single graviton is considered an immense experimental challenge due to the extreme weakness of gravity.
• The standard model of particle physics does not include the graviton.

Advanced Usage

• "Graviton exchange": Refers to the theoretical process by which gravitational force is transmitted between particles via the exchange of virtual gravitons.
  • The attractive force between two planets can be described in terms of graviton exchange.
• "Graviton scattering": A process studied in theoretical physics where gravitons interact with other particles or with each other.
  • Calculations for graviton scattering amplitudes are highly complex.

Variants and Related Words

• Gravitational (adjective): Pertaining to gravity.
  • The gravitational pull of a black hole is immense.
• Gravity (noun): The fundamental force that the graviton is theorized to mediate.
  • Einstein's theory of general relativity describes gravity as the curvature of spacetime.

Synonyms

• Gauge boson (for gravity): This is a more general class of force-carrying particles to which the graviton belongs.
• Quantum of gravity: A descriptive synonym emphasizing its role as the smallest discrete unit of gravitational interaction.

Notes on Meaning

The graviton is a central concept in attempts to formulate a theory of quantum gravity, which would unify general relativity with quantum mechanics. It is predicted to be massless, chargeless, and have a spin of 2. Its hypothetical existence is a key feature of string theory.

Noun

1. a gauge boson that mediates the (extremely weak) gravitational interactions between particles