Final answer:
The major ingredient of the universe is a combination of dark matter and dark energy, making up 31% and 69% of the critical density, respectively, with ordinary matter constituting only about 5%.
Step-by-step explanation:
Present evidence based on widely accepted astronomical theories and observations suggests that the major ingredient of the universe is not in the form of visible matter, electromagnetic radiation, or 'holes' such as black holes.
Instead, studies such as those incorporating the Cosmic Microwave Background (CMB) radiation and findings on dark matter and dark energy indicate that the universe's composition includes dark matter and dark energy.
In fact, detailed measurements have shown that the critical density of the universe is made up of approximately 31% matter (which includes a large percentage of dark matter) and a staggering 69% dark energy, with ordinary, luminous matter (the kinds of elementary particles we encounter on Earth) accounting for only about 5% of the universe's critical density.
It's worth noting that dark matter is a form of matter that does not interact with electromagnetic radiation, making it invisible but detectable through its gravitational effects on visible matter, radiation, and the large-scale structure of the universe, while dark energy is a mysterious force that is accelerating the expansion of the universe.