[𝔦 • ──⃝─⃝⃝⃝⃝──] 미지의 우주 the unknown universe

“Astronomers have discovered cosmic ripples in space-time caused by black holes colliding with each other in distant parts of the universe.”

With all the fascinating possibilities of hidden dimensions, parallel timelines, or hypothetical multiple universes out there, it can be easy to overlook the countless mysteries that exist in our space-time, along our own timeline, and in relation to our own universe, as well as the remarkable work being done to try to solve them. A spectacular example of this is the detection of gravitational waves.

Many millions of years ago, neutron stars and black holes colliding in distant galaxies rang out in our universe like the clapper of a cosmic bell. The resulting ripples in space-time traveled through Earth, momentarily warping the diameter of our planet by less than the width of an atomic nucleus.

In 2015 and 2017, astrophysicists were able to detect and measure that fleeting, minuscule change, allowing them to solve a key mystery of the general theory of relativity, first published by Albert Einstein a century earlier.

As new discoveries are made, we can delve even deeper into the long-standing puzzles we grapple with: such as whether gravitational waves finally confirm the existence of gravitons, the hypothetical subatomic particles that carry the force of gravity.

In the end, the questions we'll have to answer are those that have yet to be asked.

Gravitational waves were only detected after nearly half a century of effort by thousands of scientists and engineers dedicated to developing, building, and operating LIGO, a continent-wide system located in the United States and consisting of two underground facilities, each 4 km long and separated by 3,000 km. However, direct detection of gravitons will likely require a much larger observatory, with a mass and volume thousands of times greater than that of planet Earth.

Even if we limit ourselves to discoveries within the observable part of our own universe, we will be left with a torrent of unanswered cosmic questions.

And in my opinion, I won't stop there.