Could our Milky Way galaxy contain a giant wormhole like the faster-than-light rapid transit system shown in the movie "Interstellar"? Theoretically, maybe so — but don't pack your bags or your rocket ship anytime soon.
The question is given serious consideration in a study published by the Annals of Physics. Researchers from Italy, India and the United States determined that when you include dark matter, the mysterious stuff that accounts for about 80 percent of the universe's mass, the density could be great enough to allow for the creation of a wormhole at the center of the galaxy's dark matter halo.
Last year, some of the team's members proposed that wormholes could exist in the halo's outer regions. The researchers said their latest paper is "an important complement to the earlier result, thereby confirming the possible existence of wormholes in most of the spiral galaxies."
"Confirming" is an overly strong word, even if it relates to "possible" rather than actual existence.
As most "Star Trek" fans could tell you, wormholes are supposed to be extradimensional tunnels that connect two distant points on the space-time continuum. Such tunnels assume that the fabric of space-time can be distorted and warped strongly enough to make the connection. If wormholes exist, they could be used to travel at what would effectively be faster-than-light speeds, and could thus serve as a kind of time machine.
For decades, wormholes have played key roles in science-fiction tales — most recently in "Interstellar."
One of the paper's authors is Paolo Salucci of the International School for Advanced Studies in Trieste, also known by the Italian acronym SISSA. In a news release, Salucci said a hypothetical wormhole at the center of the Milky Way could be navigable, just like the wormhole that Murph Cooper (played by Jessica Chastain) puzzled over in "Interstellar."
"What we tried to do in our study was to solve the very equation that the astrophysicist 'Murph' was working on. Clearly we did it long before the film came out," he joked. "It is, in fact, an extremely interesting problem for dark matter studies."
Salucci emphasized that "we're not claiming that our galaxy is definitely a wormhole, but simply that, according to theoretical models, this hypothesis is a possibility." The research team says that if such wormholes do exist, they could be detected by looking for gravitational lensing effects.
Today, most physicists suspect that dark matter takes the form of exotic subatomic particles that may be discovered during future experiments at the Large Hadron Collider — but Salucci said that's not necessarily the case. "Dark matter may be 'another dimension,' perhaps even a major galactic transport system," he said. "In any case, we really need to start asking ourselves what it is."
There are plenty of wormhole theories out there — and Lawrence Krauss, a theoretical physicist at Arizona State University and author of "The Physics of Star Trek," cautioned against taking this latest hypothesis too seriously.
"My understanding of wormholes is that we have no idea how to make them stable and traversable without exotic unknown forms of energy," he told NBC News in an email, "so any discussion of traversable wormholes as realistic travel devices is highly speculative at best."
In addition to Salucci, the authors of "Possible Existence of Wormholes in the Central Regions of Halos" include Farook Rahaman, P.K.F Kuhfittig, Saibal Ray and Mosiur Rahaman.