Astrophysicists showed this in a study published in the journal Universetheoretical possibility of existence wormholes passable in the expanding universe that allow the connection of two points very far apart.
“A wormhole is a type of very curved geometry. It looks like a tunnel between distant regions of the same universe or between different universes. These structures were first discussed in the context of solving the gravitational field equations a hundred years ago. But the considered wormholes then turned out to be impassable even for photons: they could not move from one ‘end of the tunnel’ to the other, let alone return,” explains the author of the study. Kirill Bronnikovdoctor of physical and mathematical sciences and professor at RUDN University in Russia.
Other traversable wormholes are now being considered in various theories of gravity and the presence of different types of matter. “We are investigating possible traversable wormholes in general relativity that are supported by dust-like matter,” Bronnikov added.
Astrophysicists have studied the generalized form of the famous The Lemaître–Tolman–Bondi solution, which describes the development of spherically symmetric distributions of electrically neutral dust in general relativity. Scientists have generalized this to the case where there is an external source of electric or magnetic field and a non-zero cosmological constant. Their goal was to find the mathematical conditions under which permeable wormholes could exist in such an environment, and then provide a cosmological explanation.
The expanding universe
The researchers obtained numerical solutions that describe the movement of photons through wormholes connecting different Friedmann universes (Alexander Friedmann obtained theoretical models of the universe in motion, based on Einstein’s general theory of relativity) or different parts of the same universe.
The possibility of passing through a wormhole depends on the parameters of its “entrance” and initial conditions. Physicists have generalized the case of one universe to the case of multiple universes. In this case, the “mother” universe has several wormhole “entrances” connecting it to the “child” universe.
«A charge on one ‘pole’ inevitably leads to an opposite charge on the other. At this other pole there could be a similar mouth of a wormhole, and beyond that another universe, and so on. The whole picture will resemble churchkhela, a wonderful Georgian dessert. Some of the wormholes may connect different parts of the same universe,” Bronnikov explained.
“Possible observational signatures of such objects, particularly the properties of the cosmic microwave background and magnetic fields, may be the subject of future research. “It is particularly interesting to compare the characteristics of our wormhole models with the observed parameters of cosmic voids and other inhomogeneities in our universe,” Bronnikov concluded.
