宇う宙ちゅうの地ち平へい線せん

expression, noun

particle horizon; cosmic horizon

In cosmology, the boundary of the observable universe beyond which light has not had time to reach us since the Big Bang. Related to 事象の地平線 (event horizon), but distinct.

See also: 事象の地平線

• 宇う宙ちゅうの地ち平へい線せんの向むこう側がわは、現げん在ざいの技ぎ術じゅつでは観かん測そくできない。

  Beyond the cosmic horizon, we cannot observe with current technology.

• 宇う宙ちゅうの地ち平へい線せんは、宇う宙ちゅうの年ねん齢れいと光ひかりの速そく度どによって決きまる。

  The particle horizon is determined by the age of the universe and the speed of light.