According to science our universe has a beginning (search at “age of the universe” on pnas.org) and time is purely physical. Therefore there can be no such thing as time external to the physical universe. Timespace has a beginning.It is a fundamental law of physics (causality) that every physical occurrence in the universe has a cause.The fundamental laws of physics then require a cause of the universe ex nihilo (since timespace has a beginning); i.e., a Prime Cause Singularity that is non-dimensional and independent of timespace.To conclude the above paragraphs:Fact: No thing nor event in the