Question

What is the scientific consensus on the size of our universe? Is it infinite or finite (observable)? If it is finite, why do scientists think otherwise about this topic?

Answer 1

The scientific consensus regarding the size of the universe is that it is currently unknown whether it is finite or infinite. The observable universe, which refers to the portion of the universe that we can detect and study, has a finite size. However, when it comes to the overall size of the entire universe beyond what we can observe, scientists do not have a definitive answer.

The observable universe is limited by the distance that light has had time to travel since the Big Bang, which is estimated to be around 13.8 billion years. Due to the finite speed of light, there is a boundary to how far we can see. Anything beyond that boundary is currently beyond our observational reach. This boundary is often referred to as the cosmological horizon.

There are several theories and hypotheses regarding the size of the universe beyond the observable universe:

1. Infinite Universe: Some scientists propose that the universe could be infinite in size, stretching out indefinitely in all directions. This idea suggests that the universe has no boundary or edge and is unbounded.

2. Finite Universe: Others suggest that the universe could be finite in size but without a detectable edge. In this view, the universe would be similar to a curved surface (analogous to the surface of a sphere) where traveling in one direction would eventually bring you back to your starting point.

The reason scientists do not have a consensus on the overall size of the universe is primarily due to the limitations of our current observations and the complexities of cosmological models. While scientists have made significant progress in understanding the large-scale structure of the universe, the ultimate size and shape of the universe remain open questions that continue to be actively studied and researched.

Advancements in observational techniques and future discoveries may provide new insights and potentially resolve this question. It is worth noting that scientific understanding evolves over time, and our understanding of the size of the universe may change as new evidence emerges.