While we just don’t know, most physicists say no, especially if the Lambda model continues to hold up. If it were infinite and filled with galaxies and the universe is old enough for light to get here, then the night sky would be as bright as day time, but it’s not. This is summed up in what’s known as Olbers’ Paradox, which highlights the limitations in brightness and visibility due to the universe’s age and the speed of light. This also relates to whether the universe has a center in the conventional sense, and it appears to does not.
Reflecting on the concept of an infinite universe, it’s essential to consider the historical context of human understanding. Long before the recognition of Earth as a spherical planet, our ancestors perceived their world as a flat expanse that possibly stretched into infinity. The idea of the Earth having any sort of edge was beyond the realm of imagination for many. Today, we face a similar challenge in understanding the universe’s structure. Current theories suggest that the large-scale geometry of the universe might be curved, much like the Earth, but the full nature of this curvature and its implications remain elusive. Just as early explorers gradually pieced together the shape and limits of our planet through observation and exploration, we too continue to probe the cosmos, observing, exploring, and speculating with the tools and knowledge at our disposal. Our journey to understand the universe echoes the ancient journey to understand our Earth, reminding us that our perceptions of reality are often just the beginning of deeper discoveries. For a deeper exploration of our expanding universe, take the 9-minute deep dive: The Expanding Universe Explained.