What if we – and our entire universe – are inside a black hole? What if the edge of the universe that we can never reach is actually the event horizon of a black hole?
Many people have wondered: If the Big Bang started everything, then what existed before the Big Bang?
A black hole is also an infinitely dense point in spacetime
Some suggest that we must accept that we will never understand the answers to such questions. After all, even the James Webb Space Telescope – the most powerful telescope in history – can look back 100 million years after the Big Bang (according to NASA), but it still cannot peer through the very first moments of existence.
We know that the Big Bang occurred roughly 13.7 billion years ago. Just 10 to the power of -36 seconds after the Big Bang – a trillionth of a trillionth of a trillionth of a second – space began to expand like a balloon. The first protons and neutrons formed about 10 to the power of -6 seconds after the Big Bang, and after three minutes, we had our first element – deuterium (a type of hydrogen).
What about before the Big Bang? Some researchers suggest that the universe existed as a single, infinitely dense point, known as a singularity. That singularity exploded and has been expanding ever since. This is fundamentally different from the nature of a black hole. A black hole is also an infinitely dense point in spacetime. However, instead of ejecting everything, it pulls everything in. Could the formation of a black hole signify the creation of a new universe within it?
However, at this moment, there are opinions suggesting that it is impossible for black holes to reach such colossal sizes as to contain an entire universe inside. This is not entirely incorrect. According to current human understanding, the smallest black hole discovered to date is named IGR J17091-3624, which is less than three times the mass of the Sun. Despite its small size, this black hole is extremely intense, capable of producing winds of up to 32 million km/h.
On the other hand, the largest black hole we have ever detected is Ton 618, which is unbelievably massive, with an event horizon spanning 262 billion miles, 43 times the diameter of our Solar System, and the entire universe having a width of about 23 trillion light-years. Yet, we have only been able to observe 1/250 of the entire universe – containing 2 trillion galaxies, according to Big Think. So how could the entire universe fit within a black hole?
As Science ABC explains, the universe is expanding so rapidly that we will never be able to reach its edge. Due to the open curvature of spacetime, our universe is likely shaped like a donut, as Live Science describes. If you try to travel to the edge of the universe, you would only be able to go around in a circle, ending up back at your original starting point.
Just as you cannot reach the edge of the universe, you also cannot reach the center of a black hole. As Einstein stipulated through the theory of relativity and the equation E = mc^2, time would stop for objects moving at the speed of light. However, an object pulled into a black hole will not exist forever. Through a process known as “spaghettification”, objects in the accretion disk of the black hole – the distorted spacetime shape surrounding its singularity – will be shredded at the molecular level while being trapped in a near-zero time frame.
So, if our universe exists within a black hole in another universe, it means that reality consists of a collection of nested universes containing black holes that house universes.
If it is true that each black hole contains its own distinct universe, then the true shape of the multiverse resembles a tree that branches out and separates into further branches. As explained by physicist Nikodem Poplawski from the University of New Haven, each black hole represents a “one-way door.” If this is correct, what created the first universe?
The black hole universe theory may help us address some other issues within physics. Specifically, as Big Think explains, it could help explain dark energy. Dark energy is the unknown force driving the expansion of the universe. No one knows what it actually is, or why the universe is not only continuing to expand but doing so at an ever-increasing rate.
Matter from the outside becomes energy inside and drives our expansion.
So, what if dark energy is due to matter from outside our black hole universe being pulled into the black hole? Matter from the outside becomes energy inside and drives our expansion. This could also help explain the early and rapid expansion of the universe after the Big Bang.
While the black hole universe theory may answer some questions, it raises others. As Inside Science points out, this theory does not explain why the initial expansion of our universe slowed down.
We also do not know how matter from the outside becomes energy inside. But assuming we could resolve all these issues, how could we test whether we are inside a black hole or not?