The essence of Einstein’s world lies in the concept of relativity.
He described it once in the following way: “When you sit with
a nice girl for two hours, it seems like two minutes. When you
sit on a hot stove for two minutes, it seems like two hours; that’s
relativity he said.” Einstein also boldly stated that there are no
absolute quantities, that the magnitude of quantities depends on
the relative velocity between an object and the observer, and that
every event and measurement is viewed differently depending on
the observer’s velocity.