Almost all of us are familiar with a black hole. A region in space time where gravity is so strong that even light can’t defy its gravity. But what if you are on a trip of cosmos and you find a white hole. Not sure, may you find one? Tighten your seat belts, now it’s your turn to explore a thrilling creature of cosmos.

A white hole is a time-reversed black hole or simply white holes are mirror twins of a black hole. in simpler terms, all the properties possessed by a black hole when reversed we simply get a white hole. Both share precisely the same mathematics and geometry, this makes the white hole more interesting. Imagine you are watching footage of black hole just pauses it and rewind it, now the footage on your screen is of a white hole.

A white hole is a sphere of no admission. Even light can’t enter a white hole. It simply means light can only leave the white hole. A white hole can be considered as a sphere whose center is a singularity and boundary is called the event horizon. For a black hole event horizon is a point no exit and for the white hole, it is a point of no entry.

Here we come across a term singularity. What singularity is? Okay, come let’s do some math. Take a sphere of mass 10kg and volume 1m^3.calculate its density. It’s quite simple, 10kg/m^3 is the right answer. What if the volume of sphere tends to zero, its density will become infinite. Now u have a sphere with an infinite density or we can say all of its mass compressed into a single point. This is what we call a singularity. Along with infinite density, it adds up the property of infinite gravity too.

Ideas for the formation of a white hole:

1. A black hole devours every object which comes under its way and shatters it into atomic or subatomic particles. Every object has information in it which get stored in a black hole. Black hole evaporates slowly and gets vanished. As the black hole evaporates, what about all the information within? This is what called black hole information paradox. According to some astronomers, the black hole has a hole inside it which opens into a white hole through a tunnel called a wormhole or Einstein Rosen bridge. Einstein Rosen Bridge is an imaginary shortcut to another universe. White hole let all the information escape in another universe. But what if matter falling into the wormhole will cause it to collapse, closing the passage between the black hole and the white hole. Some astronomers suggest that wormholes are made up of exotic matter. Anti-gravity is one of the unique feature of such matters. Exotic matter repels another object instead of pulling it. Exotic matters may be the cause of our accelerating expansion of the universe.
2. More or fewer things often come in binaries and are complementary to each other like male-female, day-night, dusk-dawn. White holes to feel like a necessary balance to the black hole. When a black hole is in its last stage it eventually turns into a white hole and spews all the matters gathered by a black hole.

3. It have been speculated that big bang is itself a white hole. A bang was a blast which spewed all the raw material of the universe and no one can enter in the bang itself. This bang looks, mathematically at least, much like a white hole.

Feasibility of a white hole:

What do you think the white hole follow the laws of nature, of course not. Every natural reaction is irreversible and highly spontaneous. Every spontaneous reaction follows SLOT (second law of thermodynamics). SLOT tells about the entropy of the isolated system. According to SLOT, if we consider a system as isolated its entropy never going to be decrease. Entropy is a measure of the degree of disorderliness. Black hole follows SLOT but the white hole fails to follow it.

For instance, let’s consider an apple. It has some value of entropy. Now cut into 4 parts, by doing so the randomness of the apple increase and so does the entropy. This is what happens near a black hole. Any object near a black hole undergoes a process called,” spaghettification”. Spaghettigication is a process by which an object would be stretched and ripped apart by gravitational forces. If you are near a black hole, your head and toe experience a different gravitational pull of nearly infinite magnitude and u will shatter into pieces. Now come back to the apple try to fix the apple pieces into a whole apple. You can’t do so, if somehow you managed to do fix it, you are just lowering its entropy. This is what a white hole do, fix all the shattered part of an object undergone spaghettification and spew it into another universe. As white holes do not follow SLOT, the possibility of its existence is quite negligible. Our universe is vast may white holes exist in some part of the universe.

Do white holes exist?

What if you are told, whatever, you are reading is just a fictional description of mathematical imagination. Yaa, that’s true, in the real universe no white holes exist, or more correctly no white holes discovered so far, May it exists. Like black holes, white holes too are a possible solution to Einstein theory of general relativity. Don’t feel disappointed.  There are some evidence which point out the existence of a white hole. In 2006 NASA’S Swift satellite recorded an extremely powerful gamma-ray outburst and named it “GBR060614”. These are the most luminous energetic explosion known to the world till now. The mesmerizing fact of this outburst is that, this burst didn’t happened in the part of the universe where it was expected. Its property is also different from gamma rays observed from a supernova burst. It lasts long for 102 seconds. This outburst was hypothesized to have been an observation of white holes.

If we date back in the ’90s   black hole too was just a paper fantasy. But now scientists had discovered the black hole and successfully captured its image by telescope named “EVENT HORIZON”. Maybe a white hole too get discovered in near future, maybe not?

A report by Shekhar