There are a number of strange coincidences at the heart of the universe, and the closer you look, the more baffling they seem to get. In fact, some of the most remarkable scientific discoveries of recent decades can be described as coincidences, with the laws of the universe itself possibly tailored to the emergence of intelligent life. From the delicate balance of dark matter and dark energy through to the size of the moon, let's take a look at some of the weirdest cosmic coincidences according to science.
Perhaps the deepest cosmic coincidence of them all is the delicate balance that exists between dark matter and dark energy. According to scientific data, we seem to be living in a very special era, with dark matter dominating the universe in previous times and dark energy set to reign in the future. These two things account for roughly 95 percent of the known universe, with dark matter gravitating like normal matter and dark energy having the opposite effect by causing the cosmos to expand. If either factor were able to dominate the other, the very existence of intelligent life would be impossible.
Another strange coincidence that involves dark energy is sometimes referred to as the "pancake problem". It seems the universe has been balancing itself on an ultra-fine point for the last 13.8 billion years, with our universe neither curving outwards or collapsing into itself. Much like the balance that exists between dark matter and dark energy, it seems we're experiencing some kind of delicate balance that would seem almost impossible if it hadn't been measured. According to cosmic microwave background radiation emitted shortly after the big bang, the density of matter and energy is so well balanced that the universe does not curve either way.
One other cosmic coincidence that may very well blow your mind is the similarity that exists between the size of the universe and the forces that define it. It seems that one huge ratio can be used to explain two very different phenomena, and once again, humans are sitting in the delicate middle ground. The age of the universe is said to be 13.8 billion years old, with the speed of subatomic processes taking a trillion-trillioneth of a second to cross an atomic nucleus. The ratio of these two time scales is roughly 10 to the 40th power, which is the very same ratio that exists between the electric and gravitational forces that have shaped the universe.
Cosmic coincidences also exist closer to home, with one very strange alignment staring you in the face each month. While most people never give it a second thought, it really is remarkable that the size of the sun and the size of the moon relative to Earth are exactly the same. This mysterious phenomenon is responsible for the existence of solar eclipses, which temporarily block out the sun and cast a shadow on the Earth. While the sun’s diameter is about 400 times greater than the moon, it's also about 400 times further away. Many of these wonderful coincidences can be partly explained with the anthropic principle, which is a philosophical idea that observations of the universe are always compatible with the intelligent life performing the observations.
Image source: Jozef Klopacka