The estimated age of the universe is often stated to be about 13.7 billion years. But I've never seen any qualifiers on that age. We know that time passes slower the greater the gravity field you're in. Even the difference in gravity between the earth's surface and orbit is enough to cause crystal oscillators in satellites to keep the wrong time if they're not adjusted for it. And every spot in the early universe would have been much closer to a gravity source than many points are today. So when we read the age of the universe (or even of the solar system or earth), is that time adjusted for gravity? Is it hypothetically measured from some point outside any galaxy where gravity is minimal? Or does it take into account the proximity to mass that must have been true in the early universe?