How do we know the universe is infinite?

Our understanding of the universe has come a long way in recent years. It has been a subject of human inquiry for thousands of years, and through the ages, we have been able to come up with various theories about its origin, nature, and ultimate fate. One of the most fundamental questions about the universe is whether it is infinite or not.

Scientists today believe that the universe is infinite. But how do we know this?

First, we can observe the universe and see that it appears to be the same in all directions. This means that there is no boundary or edge to the universe, as we would expect if it were finite.

Second, the universe appears to be expanding. We can observe this expansion by measuring the redshift of light from distant galaxies. If the universe were finite, we would expect to see the expansion slow down as the galaxies moved away from each other. However, observations have shown that the expansion is actually accelerating, which suggests that the universe is infinite.

Finally, measurements of the cosmic microwave background radiation have shown that the universe is flat, which also suggests that it is infinite.

In conclusion, while we may not be able to directly observe the entire universe, the evidence we have suggests that it is infinite.