Outer space is filled with enigmas, but perhaps none is so enthralling, or confounding, than black holes, white holes, and wormholes. Not only have these cosmic curiosities sparked the imagination of humans and deeply fascinated scientists, but they have also sparked a number of sci-fi creators to describe their various shape-shifting structures.

But what exactly are they? Are they real? And can wormholes actually facilitate time travel?

What is a black hole?

A black hole is a spot in space where gravity pulls so much that even light is unable to escape. Such an astronomical body is incredibly dense and thus has a strong gravitational force. Once someone’s falling into a black hole, they won’t be able to escape the gravitational pull.

Why are black holes so strong?

The reason that black holes are so strong is their extremely heavy mass. All the mass of the astronomical body is contained precisely in a very, very small region of space.

Composition of a Black Hole

Let’s take a closer look at the composition of black holes:

• Singularity – The singularity, or point of infinite density, is the very center of a black hole where the laws of physics break down.
• Event Horizon – The event horizon is the invisible boundary around the singularity. Once crossed, you can never get out. The event horizon is sometimes considered the “point of no return.”

What happens inside a black hole?

No one really knows. Because nothing leaves a black hole, we cannot observe what happens in a black hole. Some theories say the singularity crushes matter into an infinite point. Other theories propose more exotic things happening, such as worm holes, or even “bouncing” to other universes.

How do black holes form?

Stellar Collapse

Black holes most often form through this process. When a massive star runs out of nuclear fuel, it collapses under its own gravity, resulting in a supernova explosion. If the remaining core is dense enough, a black hole is formed.

Collision of Neutron Stars

Neutron stars (the result of smaller stars) converting to black holes by dying and joining forces, also create black holes. Evidence of this process has been captured and observed through gravitational waves.

Types of Black Holes

1. Stellar Black Holes – Are formed from collapsing stars. They typically have masses between 5-20 solar masses or more.
2. Supermassive Black Holes – Are located in the nuclei of galaxies. They can be 1 million or 1 billion times the mass of the Sun.
3. Intermediate Black Holes – Are rare and difficult to observe, but it’s believed to be the “missing link” or bridge between stellar and supermassive black holes.
4. Primordial Black Holes (Theoretical) – Should the exist, they were formed only a fraction of a second after the Big Bang, and could potentially solve various cosmic gaps, including some characteristics of dark matter.

Can We See Black Holes?

Not exactly. In fact, back in 2019, scientists obtained the first image of a black hole’s event horizon via a telescope network, known as the Event Horizon Telescope (EHT). What we see is essentially the shadow of the black hole eclipsing the bright gas and dust swirls encircling it.

What Is a White Hole?

Now flip that concept completely over. A white hole would have the exact properties of a black hole, except it emits matter and light instead of drawing it in. Nothing can enter a white hole.

You could picture a white hole like a cosmic fountain. Instead of sucking everything into a void, it sprays matter and energy out. It can be compared to watching a black hole in reverse.

Are White Holes Real?

At this stage, white holes are still theoretical. There is no observational proof that they exist. But they are solutions to the “same” Einstein field equations that also provided us with black holes. So they can exist mathematically in theory.

Could Black Holes Evolve into White Holes?
Some physicists have suggested that black holes could also evolve to become white holes over time, maybe due to quantum gravity reasons. This is possibly how they explain why information can escape black holes which challenges current physics.

What Is a Wormhole?

Let’s go on to the most exotic idea to hit the agenda: wormholes. More formally called Einstein-Rosen bridges, wormholes are theoretical tunnels through spacetime.

What Is a Wormhole in Space?

In theory, a wormhole could connect two separated parts of the universe, or even two different universes! In other words, it would be a shortcut through space and time. If you could travel from one end, you would emerge from the other end instantaneously, even if the two openings would normally be far apart in normal space.

How Are Wormholes Related to Black Holes?

While studying black holes, Einstein and Rosen also suggested the idea of wormholes. The Einstein-Rosen bridge represents the theoretical bridge between a black hole (entry point) and a white hole (exit point).

Can a Wormhole Allow Time Travel?

Now for the tricky bit: yes, some theories suggest that wormholes could indeed allow time travel. If one end of the wormhole passes through time differently (thanks to the laws of special relativity) then time will pass at a different rate on that end. Thus we’d have a potential time machine.

Problems to Time Travel through a Wormhole

Unfortunately, the potential does not come without problems:

• Unstable: Wormholes could collapse before anything has a chance to travel through them.
• Exotic Matter: You would require exotic matter with negative energy density to keep the wormhole open.
• Causality problem: Oooo don’t get us started on the problems with causality. (Think grandfather paradox, if you go back and change something, what happens?)

Do wormholes actually exist?

We have not yet observed a wormhole. (No wormholes have ever been seen). Wormholes are entirely theoretical, but that doesn’t stop many physicists from taking them seriously. Some physicists believe that a unifying theory combining quantum gravity may create or allow for the observation of the real thing!

Can humans travel through wormholes?

In theory, maybe. But in reality, far from it. If wormholes exist, they will probably be unstable and microscopic. Some theories suggest trying to enlarge wormholes using exotic matter, but that’s a far cry from what we can do now.

What Happens If You Go Through a Wormhole?

The short answer is we don’t know. You could go through instantly, or you could get obliterated, or something else entirely. It depends on the wormhole, the spacetime surrounding it, and the matter involved.

Black Holes, White Holes, and Wormholes and their connections:
These three topics of black holes, white holes, and wormholes are all connected in theoretical physics. In one possible scenario:

• Matter goes into a black hole.
• The matter travels through a wormhole.
• Finally, it exits via a white hole in another universe.

This idea questions everything we think we know about spacetime, information, and about life itself.

Are there wormholes existing in our galaxy?

There is no evidence. Yet, some astronomers think that unusual behavior of gravity or movements in galaxies might be indirect evidence wormholes do exist. The fact is, we simply do not have the technology to directly search for wormholes yet.

Conclusion

The universe contain truly wild concepts from the terrifying nature of black holes, and the explosive potential of theoretical white holes, to the mind-bending possibility of wormholes being shortcuts across space and time, the universe never lack in the amazing.

These phenomena challenge our comprehension of physics, but they also inspire imagination. While we have seen black holes first hand, there is evidence of white holes and wormholes, but they remain mysteries indicating where our science ends.

If anything has been demonstrated in the past, today’s science fiction often becomes tomorrow’s realization.

Quick Fun Facts About Black Holes

• Sagittarius A is the supermassive black hole at the center of our galaxy, weighing 4 million Suns!
• Black holes can “sing” by producing gravitational waves when they merge.
• Wormholes are also called Einstein-Rosen bridges, cosmic shortcuts through space.
• Time slows down near black holes, you could age slower if you got close!
• White holes are purely theoretical and might be the Big Bang’s “reverse.”
• The first-ever black hole image was of M87*
• We orbit inside the Milky Way’s black hole gravity well every day!

Read about: The Digital Detox Trend That’s Changing Lives