How close are we to building a wormhole that will take us to other times?

Have you ever imagined a space highway without limitations? We are not suggesting to build an extension of the magnificent hypothetical elevator that leaves the Earth towards its orbit dreamed for the first time in the mind of the Soviet Konstantin Eduardovich Tsiolkovsky, ‘the Father of Cosmonautics’ (1895), but of a physical probability that would grant us the power to open shortcuts from one universal coordinate to another: a wormhole.

As Arthur C. Clarke said in a moment of prominent lucidity: “What began today as a science fiction novel, tomorrow will be finished as a reportage.” Wormholes, a prediction of the general relativity theory exemplify the words of the author of “2001, a space odyssey” to the letter.

The oldest antecedents on the discussions of this hypothesis date from the year 1916. Solving field equations of the theory of relativity, the Austrian physicist Ludwig Flamm proposed that the understanding of the Einstein-Rosen bridge —later called it that way by a study of 1935 published in the journal Physical Review Letters in the name of Albert Einstein and Israeli physicist Nathan Rosen—might be tempted.

The authors of the cited study also noted that each black hole region of space where not even light can escape its gravitational pull, it would be paired with a white hole, with opposite properties to its dark twin, and the throat separating the two would be the wormhole.

The 1950s arrived and John Wheeler, a renowned physicist from Johns Hopkins University, also tried to describe the phenomenon in his own style.

Wheeler and Einstein —separately— worked on the theoretical model with unstable wormholes, that is, a variant that opens like a portal in space-time, little by little, and disappears or evaporates sporadically.

In the fortnight of October 1962, in this regard, John Wheeler and Robert W. Fuller, a physicist at Princeton University, questioned whether a signal from the cosmos traveling on a route at the speed of light (about 300.00 km/s ) could be surpassed by one that uses a much shorter path or wormhole.

The simple fact of mentioning something capable of winning the race at the speed of light —indirectly, of course— already leads the entire community of specialists, old or promising, to perplexity.

Will we manage to build a wormhole that allows us to return to the past or push us to visit incalculable galactic directions? Both in fiction and in reality, scientists have already begun to take the premise seriously despite the fact that it takes years to master the probable laws hidden behind those passageways of relativity.

According to an article published on November 20, 2013, the quantum entanglement of a quark (elementary particle) and an antiquark would generate the appearance of a wormhole that connects this pair.

Julian Sonner, the sole signatory of the study, from the Nuclear Science Laboratory and Center for Theoretical Physics at MIT (Massachusetts Institute of Technology), published his results based on the theory that a black hole and a white hole, whose density deforms the space-time, throws out matter and doesn’t let anything in, are joined quantumly by an Einstein-Rosen bridge.

“There are many paths that can be followed in this investigation and this work can be very useful in that sense,” Sonner was encouraged to declare at the time.

Sonner created the quark and antiquark in a laboratory environment with quantum concepts that allow something to come out of nothing (Schwinger effect). Before they disappear, he applied an electric field to them. Then the scientist appreciated the wormhole. However, what remains unclear is how to sustain the stability of this basic representation.

Two studies were in the public eye in 2021 for trying to explain what would happen to a human if they crossed the jaws of an Einstein-Rosen bridge.

One of them, signed by Juan Martín Maldacena of the Institute for Advanced Studies and Alexey Milekhin of Princeton University, stated that, by simulating the existence of more than four dimensions (Randall-Sundrum model), an explorer could transit a black hole . The results were published in Physical Review D.

The weakness is that, according to Maldacena, his team used a class of “exotic matter”, although the solution “respects the principles of known physics”, but adding the assumed variables to an unproven theory about slippery tunnels such as Einstein- Rosen produce twice as many doubts.

In the other work uploaded to Physical Review Letters, three scientists dismissed such exotic matter and changed it to ordinary matter. They focused on unifying general relativity theory, Maxwell’s electromagnetic field theory, and Dirac’s theory for fermions (elementary particles). Thus, they concluded that wormholes would remain on a microscopic scale. What would be the strategy to stretch it? We await that response.

Do all wormholes really collapse immediately? Physicist Pascal Koiran of the Ecole Normale Supérieure de Lyon in France used a technique called the “Eddington-Finkelstein metric” to trace the path of a particle through a wormhole.

He observed that the particle did not misbehave as it entered the space-time tunnel and exited. The chaos, then, could be avoided. The preliminary results are hosted on the arxiv platform.

However, the bad news remains instability. Scientists have a hard time predicting the wormhole’s ultimate fate. There is always pessimism. Although the space-time tunnel was shown to be able to evade catastrophic concepts that are thought about its existence, when it remains fully operational, theoretical physicists will plunge into the oceans of the microcosm to see beyond the iceberg.

The history of wormholes linked to literature and cinema dates back to the publication of the book “Contact” (1985) by Carl Sagan, former host of the documentary series “Cosmos: a personal journey” (1980).

It was thanks to Kip S. Thorne, winner of the 2017 Nobel Prize in Physics for “decisive contributions to the LIGO detector and the observation of gravitational waves”, that Sagan organized very important details of his work to nourish it with more credibility, an essential balance point in science. fiction.

Today, referring to Thorne is just as inspiring. The eminence in general relativity was also in charge of the executive production of the film “Interstellar” (2014, Christopher Nolan).

To fulfill the goal of fruitful communication with extraterrestrial intelligences, Sagan chose to send protagonist Eleanor ‘Ellie’ Arroway to a nearby star using black holes as a shortcut, but he wasn’t sure he could put that mechanism on paper, so he asked Thorne for advice.

Kip S. Thorne replied that the intractable power of the singularity would annihilate the traveler. He then suggested that Arroway go through a wormhole instead of a black hole, although little was known about such tunnels.

According to Kip, a civilization of technology far superior to ours could create them by applying twinned mathematics to these two options:

It was only on September 26, 1988, that this Caltech-educated scientist, an old friend of Stephen Hawking, managed to get the Physics Review Letters to bring out a paper well adjusted to the bases, directing his conjectures towards laudable hierarchies of knowledge.

Accompanied by the co-authors of that manuscript, Michael S. Morris and Ulvi Yurtsever, Thorne stated: “It is argued that if the laws of physics allow an advanced civilization to create and maintain a wormhole in space for interstellar travel, then that wormhole can become a time Machine”.