What of these can be considered part of the natural universe studied by scientists?

The natural universe studied by scientists includes all physical matter and energy, as well as the fundamental forces that govern their interactions. This encompasses everything from subatomic particles to galaxies, as well as phenomena such as gravity, electromagnetism, and thermodynamics. Scientists explore these elements through observation, experimentation, and theoretical modeling to understand the laws of nature and the origins of the universe. Concepts that are purely philosophical or metaphysical, such as those beyond physical observation, do not fall within this scope.