Cosmic Mysteries: Shedding Light on Dark Matter

Einstein wowed the world with his earth-shattering theories of relativity that have stood up to experimental scrutiny. Einsteinian intuition also decreed that the universe was a static entity even though the equations suggested otherwise. To resolve this discrepancy, Einstein 'fudged' his equations with a cosmological constant that counteracted gravity to enable a static universe. But when Edwin Hubble proved that the universe was indeed expanding, Einstein described the cosmological constant as "the biggest mistake of his life". It's somewhat consoling that even geniuses have regrets.

But when astonomers ultimately established that the universe was not just expanding, it was actually accelerating outwards, the generally accepted explanation has been that our cosmos is pervaded by exotic matter termed dark energy that opposes gravity and allows massive bodies to pull away from each other. This dark energy could be equivalent to a non-zero cosmological constant, suggesting that Einstein had been on to something.

Scientists have been probing the dark side by studying the relative positioning and movement of galaxies and clusters. They hope these models will allow them to establish a range of values for the strength of dark matter.

In comparing theory to practice, scientists suggest that the expected energy latent in the vacuum of space is 120 magnitudes higher than what's expected. Some have speculated that implies that there's more to the vacuum of space than we realize, possibly worm-holes that allow travel between space and time, or maybe parallel universes playing out different evolving scenarios.

One thing's for certain: if the universe does indeed continue to expand at its current rate, the Milky Way and Andromeda can never collide. It also means that in 100 billion years, no galaxy will be visible from the Milky Way which will be kind of a bummer for astronomers.

But then again, the universe just can't keep expanding forever, can it?