Wormholes are extremely unstable structures. Even if a photon slips in, the wormhole closes in an instant. But is it because our imagination of wormholes is not enough odd and quirky? The secret to giving the wormhole a stable structure may be to change its appearance, according to a new study. If the wormhole is no longer a perfect sphere, it may be open enough for us to cross it. The only problem is that the wormhole must be too small to imagine.
Deep into the wormhole
If the wormholes do exist, they can allow you to get from point A to point B in a very distant distance in a flash, the equivalent of using a “cheat code” to take you a close path. See the star in the night sky millions of light-years away? If you have a wormhole that connects you to this star, you can reach it in just a few minutes. It sounds so magical that it’s no wonder that wormholes are almost the standard of science fiction.
But the wormhole is not the product of our imagination, but the result of Einstein’s general theory of relativity. General relativity is the modern understanding of the mechanism of gravitational action, the idea that matter and energy can make the texture of space-time bend or twist, and the bending and distortion of space-time in turn will affect the way matter moves.
One can’t help but wonder if time and space can be bent to the point where it overlaps itself. This allows a short channel to be built between two points that are far apart.
In 1970, scientists were surprised to find that the answer to this question was yes. In the framework of general relativity, wormholes are possible.
There is only one problem: these wormholes are very prone to collapse, and often fall apart as soon as they form.
The key to stability
Wormholes are so unstable because they are essentially made up of two black holes that come into contact with each other. The two black holes are connected to each other at their respective singopoints, forming a channel.
But the singty point is infinitely dense and surrounded by a circle of areas called event horizons. Event horizons are a boundary that goes back, and once you cross the black hole’s event horizon, you can no longer escape from it.
To solve this problem, the entrance to the wormhole must be located outside the event horizon. This way you can pass through the wormhole without breaking into the event horizon and never escaping.
But once you get into the wormhole, it’s full of your mass, and your gravity distorts the wormhole channel, causing the wormhole to collapse, like a rubber band that’s too much of a pull, leaving only two separate black holes (your body fragments are scattered throughout the universe).
And scientists have found a way to keep the inlet of the wormhole outside the event horizon while keeping the wormhole stable long enough. But this method requires the use of negative mass substances. Negative mass is no different from ordinary mass, except for an additional “negative” word. If you collect enough negative mass substances and focus them in one place, you can keep the wormhole open.
But as far as we know, substances with negative mass do not exist. We have not found evidence of their existence, and if such matter does exist, it will violate many laws of the universe, such as inertia and momentum conservation, and so on. For example, if you kick a negative mass ball, it will fly backwards, and if you push a negative mass object toward a positive mass object, they will not attract each other, but will be mutually exclusive, always moving in a state of acceleration far away from each other.
Since there seems to be no negative mass in the universe, wormholes seem unlikely to exist.
Finding solace in quantum theory
But the above assumptions about wormholes are based on general relativity. This is our current understanding of the mechanisms of gravity, and this understanding is not perfect.
We know that general relativity cannot describe all gravitational interactions in the universe, because this theory fails for extreme gravity at very small scales, such as the sings inside a black hole. To solve this problem, we need quantum gravity theory, which combines our understanding of the world of subatomic particles with our understanding of large-scale gravity. But quantum gravity theory has not yet taken shape, because whenever we want to combine the theory of the micro-world with the theory of the macro-world, we will eventually encounter a difference.
However, we have some guesses about the mechanism of quantum gravity. And the more we study it, the more we know about the feasibility of wormholes. We may see gravity from a new, better perspective, under which we don’t need negative mass at all to build stable, walkable wormholes.
Two theorists at Tehran University in Iran have published a new study of worm holes on the paper’s preprinted website arXiv. Using some special techniques, they studied how quantum mechanics might change the framework of standard general relativity. Stable wormholes may not need negative mass material, but the inlet of wormholes needs to be slightly elongated and not perfect, the study found.
While the findings are interesting, there is one drawback: these hypothetical traversable wormholes are so small that they are only 1.61 x 10-35 in diameter, and that no one or object who wants to cross through them can be larger than that, and must operate at speeds close to the speed of light.
Despite its limitations, the study did open a gap in the wormhole issue, opening the possibility for more follow-up studies.