Wormholes play an essential role in various science fiction films — connecting two distant points in space. However, According to physics, these tunnels in spacetime are purely theoretical. Dr. Jose Luis Blázquez-Salcedo from the University of Oldenburg supervised an international team that has now introduced a new theoretical model in the science journal Physical Review Letters that make microscopic wormholes appear less far-fetched than in earlier theories.
Like black holes, wormholes also appear in the equations of the general theory of relativity by Albert Einstein, published in 1916. According to an essential postulate of Einstein’s theory is that the universe has four dimensions — three spatial dimensions (up and down, left and right, back and forth), and the fourth dimension of time.
Collectively they form spacetime, and spacetime can be extended and curved by enormous objects such as stars, much as a rubber film would be curved by a metal ball immersing into it. The curvature of spacetime determines the way objects like planets and spaceships, but also light, travel within it.
According to the theory of Blázquez-Salcedo, spacetime could also be bent and curved without enormous objects. In this case, a wormhole would be an exceptionally curved area in spacetime that resembles two interconnected funnels and unites two different spots in space, like a tunnel. “From a mathematical viewpoint such shortcut would be permissible, but no one has ever recognized an actual wormhole,” the physicist explains.
Further, such a wormhole would be unstable, for example, suppose a spacecraft was to fly into one, it would spontaneously fall into a black hole — an object in which thing vanishes, never to be seen again. The connection is given to other regions in the universe would be cut-off. Earlier models recommend that the only means to keep the wormhole open is with an exotic form of matter. It has a negative mass, or in simple words, it weighs less than nothing, and it only exists in assumption.
Though, Eugen Radu from the Universidade de Aveiro in Portugal and Blázquez-Salcedo and his associates Dr. Christian Knoll from the University of Oldenburg, explain in their model that wormholes could also be traversable without such matter.
The scientist picked a relatively simple “semiclassical” strategy. They merged elements of quantum theory with elements of relativity theory and classic electrodynamics principles. In their model, they scrutinize specific fundamental particles such as electrons and their electric charge as the matter that is to pass through the wormhole.
As a mathematical explanation, they took the Dirac equation. According to quantum theory and relativity, an equation that represents the probability density function of a particle is known as the Dirac field.
As the scientists state in their research, it is the addition of the Dirac field into their model that allows the existence of a wormhole traversable by matter. However, the ratio between the electric charge and the mass of the wormhole exceeds a certain limit. In addition to matter, electromagnetic waves could also cross wormholes in spacetime. The microscopic wormholes proposed by the team would not be suitable for interstellar travel. Furthermore, the model would have to be further improved to discover whether such unique structures could exist. “We believe that wormholes can also exist in a comprehensive model,” says Blázquez-Salcedo.
Reference: “Traversable Wormholes in Einstein-Dirac-Maxwell Theory” by Jose Luis Blázquez-Salcedo, Christian Knoll and Eugen Radu, 9 March 2021, Physical Review Letters.