Have you ever sat in bad rush hour traffic (isn’t that redundant?) and said to yourself, “I could get out of this if I had a wormhole”? Me neither, but apparently some astrophysicists have and they’ve developed and published a set of step-by-step do-it-yourself instructions for building one – along with the prerequisite admonishments that these are for informational purposes only and you shouldn’t try this at home. HA! Let’s get started with our wormhole.
“We construct traversable wormholes by starting with simple four-dimensional classical solutions respecting the null energy condition and containing a pair of oppositely charged black holes connected by a non-traversable wormhole. We then consider the perturbative back-reaction of bulk quantum fields in Hartle-Hawking states. Our geometries have zero cosmological constant and are asymptotically flat except for a cosmic string stretching to infinity that is used to hold the black holes apart. Another cosmic string wraps the non-contractible cycle through the wormhole, and its quantum fluctuations provide the negative energy needed for traversability.”
OK, so all we need are a couple of oppositely charged black holes and two cosmic strings. For where to order those online, you might want to check with Zicao Fu, Brianna Grado-White, and Donald Marolf, authors of “Traversable Asymptotically Flat Wormholes with Short Transit Times,” a preprint paper published recently in arXiv.org. Fu is a PhD candidate, Grado-White a graduate student and Marolf a professor in the Department of Physics at the University of California, Santa Barbara. Their paper does indeed give step-by-step instructions, including the supporting documents and mathematical formulas, for building a wormhole that doesn’t have the instability problem most wormholes have.

“But this wormhole-via-charged-black-holes has two issues. One, it’s still unstable, and if something or someone actually tries to use it, it falls apart. The other is that the two oppositely charged black holes will be attracted to each other — both through gravitational and electric forces — and if they fall together you just get a single, big, neutrally charged and altogether useless black hole.”
Fortunately for those of us who are not astrophysicists, astrophysicist, Paul Sutter at The (trademark pending) Ohio State University has a simple explanation in Live Science. His good news is that charged black holes are real. His bad news is that using a pair with opposite charges means they want to come together right now over me. (John Lennon would have LOVED the idea of wormholes.) The good news is, a cosmic string – extremely thin 1-dimensional topological defects which may have formed during the early days of the universe – could be used to keep them separated … not perfectly, but better than the referee between contestants in a professional wrestling match. The paper suggests getting two cosmic strings and forming a closed loop between the black holes. The loop would then vibrate and churn the space around them until the energy goes negative, creating a negative mass that would stabilize the wormhole, allowing matter (cars?) or even just messages (Anybody home? Marco!) to pass through.

The bad news is (you knew there was more), cosmic strings are hypothetical. However, Sutter gives one more tantalizing bit of good news:
“Still, there’s no reason they can’t exist, so they’re fair game.”
Fair game? Game on! Stop wasting your time honking your horn in that traffic jam and start figuring out a way to get some black holes and a couple of cosmic strings.
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