A basic picture of our understanding of the physical universe is a necessary part of trying to present any proper understanding of the place of humans in the cosmos, in so far as we have such an understanding, or of trying to present some picture of whatever our relationship is to the cosmos.

It should be made clear that our understanding of the physical universe is still quite incomplete, and that the areas this lack of understanding extends to include:
- early history of the universe,
- the exact nature of the forces and energies that make up the physical universe,
- whether there are large amounts of hidden matter and energy in the universe,
- what the eventual of the universe will be, or if it will end,
- whether this universe is part of some vastly larger multiverse,
- whether this universe is one of infinitely many stretching forward and backwards in time.

It should also be made clear that the physical sciences do not deal with philosophical concepts such "meaning" or "purpose". Neither do they deal with religious questions such as whether the physical universe is just one level or aspect in a greater cosmos that contains other non-physical aspects or realms, nor do they deal with the question of whether there is a God or Supreme Being, and what the relationship of this Supreme Being to the physical universe might be.

Having set out the limitations of what is known by the physical sciences, and the boundaries (such as they are) of what is investigated by the physical sciences, the picture of the nature and structure of the physical universe that the physical sciences present us with might include the following:
- the origin, age and large scale structure of the universe,
- the role of gravity in the formation of galaxies, stars, planetary systems, etc.,
- how light and other electromagnetic energy is generated in the sun and other stars,
- dark energy, dark matter and atomic matter,
- the chemical composition of the matter in the universe, and the relative occurrence of the different elements in the universe,
- the structure of matter in terms of elements and compounds,
- creation of the heavier elements in stars,
- the structure of matter in terms of atoms, molecules and chemical bonds, and how most matter is empty space,
- composition of atoms in terms of electrons, protons, neutrons, quarks and other more fundamental particles, wave-particle duality,
- the states of matter and the transition between states, crystals,
- the fundamental forces (gravity, electromagnetic, weak, strong),
- antimatter.