Time, not dark energy, may be causing the universe to expand

27 December 2024

Dark energy does not exist, and the universe, while continuing to expand, is not doing so in a uniform fashion. In other words, the cosmos may look more like a potato, rather than a sphere. This according to recent research by astronomers and scientists at the University of Canterbury (UC), based in Christchurch, New Zealand.

As if that’s not startling enough, things become truly mind boggling when we look at the nature of time in a universe that may be devoid of dark energy. Time, you see, is moving at different speeds, depending on the location. Within our galaxy, the Milky Way, a clock ticks more slowly than one that might be situated elsewhere in an empty region of the universe, say the mid-point between our galaxy and the Andromeda galaxy, which is two and a half million light years distant.

The model suggests that a clock in the Milky Way would be about 35 percent slower than the same one at an average position in large cosmic voids, meaning billions more years would have passed in voids. This would in turn allow more expansion of space, making it seem like the expansion is getting faster when such vast empty voids grow to dominate the universe.

Because there is more gravity inside a galaxy than outside, clocks will be slower. This is a concept called gravitational time dilation, which Albert Einstein predicted when he published the theories of special relativity and general relativity, early in the twentieth century. Differences in clock speeds may not be surprising then, but the UC research illustrates just how stark these variations might be.