Final answer:
The universe’s expansion may either decelerate due to gravity but continue indefinitely, or accelerate due to dark energy leading to a rapid expansion.
Step-by-step explanation:
Two of the four possible expansion patterns of the universe include a model where the universe keeps expanding but at an ever-slower rate, and another where the universe expands at an accelerating rate due to dark energy. In the slowing expansion model, the universe will continue to expand forever, but the expansion slows down as time advances due to the gravitational pull of the matter in the universe. In contrast, the accelerating expansion model suggests that as the universe gets larger and matter becomes more thinly spread, dark energy, which acts over large scales, becomes more influential, leading to an increase in the rate of expansion over time.
Two distinct expansion patterns of the universe are characterized by differing rates of change. In the slowing expansion model, the universe continues to expand perpetually, but the rate gradually decreases over time. This deceleration is attributed to the gravitational pull exerted by the matter distributed throughout the universe. Conversely, in the accelerating expansion model, as the universe expands, matter becomes more sparsely distributed. Dark energy, a force acting on large scales, becomes increasingly influential, resulting in an accelerated expansion rate over time. This scenario posits that the expansive force driven by dark energy outweighs the gravitational deceleration caused by matter. These contrasting models offer insights into the dynamic interplay between gravitational and dark energy forces, shaping the destiny and evolution of the vast cosmic landscape.