Yes, but that frequency depends on the caesium-133's frame of reference. In a deep gravity well or at "high" speed, caesium-133 emits at a lower frequency relat

Yes, but that frequency depends on the caesium-133's frame of reference. In a deep gravity well or at "high" speed, caesium-133 emits at a lower frequency relative to caesium-133 in deep space moving at "low" speed.