How scientists think the universe will end

Billions of years from now, the universe will come to an end. At least, that’s what many scientists think. With our current understanding of physics, researchers believe that the end is inevitable.

Yet how the universe will end remains hotly debated.

For a long time, many researchers believed that the universe would eventually suffer a Big Crunch. The Big Bang theory, accepted by virtually all experts, posits that the universe began when an infinitely dense and hot energy point rapidly expanded — doubling in size at least 100 times in just fractions of a nanosecond. The Big Crunch would essentially be the opposite of that.

According to the Big Crunch theory, the universe’s expansion will continue until gravity finally forces it to contract and collapse in on itself. If the collapse unfolds, all matter will eventually smash together and create immense heat and gravitational force. By this point, most life in the universe would likely be long-dead.

Yet when scientists devised ways to measure the speed of the universe’s expansion, they made a startling discovery: The expansion was not slowing down as they expected. Instead, it was accelerating, which means there are other factors at play that we don’t fully understand.

If the universe continues to expand, the matter will slowly spread out. Stars will start dying and with matter spread too thin, new stars won’t be born. This could lead to heat death as the universe cools down. Other scientists believe that the universe will keep expanding forever until eventually, not just galaxies but even individual atoms will be torn apart.