particle horizon
Astronomy
noun
A notional surface surrounding an observer, from beyond which no particle or information could have reached the observer during the lifetime of the universe.
Origin
1950s.
- dialect atlas
- dialected
- dialect geographer
- dialect-geographical
- dialect geography
- dialectic
- dialectical
- dialectically
- dialectical materialism
- dialectical materialist
- dialectical theology
- dialectician
- dialecticism
- dialectise
- dialectize
- dialectologer
- dialectological
- dialectologist
- dialectology
- dialectual
- dialer
- dial-in
- dialing scale
- dialing sphere
- dial in (or into)