To talk intelligibly about modern physics, we have to admit the possibility of uncaused events.

When confronted with a demand that the universe have a cause, infidels have usually pointed out that God was not much of an explanation. This is true enough, but not really a positive argument. After mechanistic explanation became popular, infidels liked to restrict causality to the chain of causes in an eternal material universe, pointing out that no supernatural cause was then necessary. Plausible, but still rather defensive. Today's skeptic can do better. In all likelihood, the universe is uncaused. It is random. It just is.

Asking about a time before the beginning of our spherical spacetime is like asking what lies north of the North Pole. There is no such thing.

Quantum mechanics is so counter-intuitive, physicists have never been able to come up with a comfortable picture of how it works.

Which is better: to achieve Nirvana, or become a Boddhissatva?

Attaching a Creator to the boundary is metaphysical skullduggery.

Quantum events have a way of just happening, without any cause, as when a radioactive atom decays at a random time. Even the quantum vacuum is not an inert void, but is boiling with quantum fluctuations. In our macroscopic world, we are used to energy conservation, but in the quantum realm this holds only on average. Energy fluctuations out of nothing create short-lived particle-antiparticle pairs, which is why the vacuum is not emptiness but a sea of transient particles. An uncaused beginning, even out of nothing, for spacetime is no great leap of the imagination.