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My question is related to the first page of this article regarding the big bang theory and refers to this specific sentence:
Armed with the best physics of the 20th century, Albert Einstein came to very similar conclusions with his theory of relativity. Just consider the effect of mass on time. A planet's hefty mass warps time -- making time run a tiny bit slower for a human on Earth's surface than a satellite in orbit. The difference is too small to notice, but time even runs more slowly for someone standing next to a large boulder than it does for a person standing alone in a field. The pre-big bang singularity possessed all the mass in the universe, effectively bringing time to a standstill.
Considering that, here is my question: Does time actually run slower for a human standing next to a boulder? How does that work and how/where can I find out more?