Physicists Just Released Step-by-Step Instructions for Building a Wormhole



Physicists Just Released Step-by-Step Instructions for Building a Wormhole

spinning black hole with spacecraft entering

(Image: © Shutterstock)

Everybody wants a wormhole. I mean, who wants to bother traveling the long-and-slow routes throughout the universe, taking tens of thousands of years just to reach yet another boring star? Not when you can pop into the nearest wormhole opening, take a short stroll, and end up in some exotic far-flung corner of the universe.

There’s a small technical difficulty, though: Wormholes, which are bends in space-time so extreme that a shortcut tunnel forms, are catastrophically unstable. As in, as soon as you send a single photon down the hole, it collapses faster than the speed of light.

But a recent paper, published to the preprint journal arXiv on July 29, has found a way to build an almost-steady wormhole, one that does collapse but slowly enough to send messages — and potentially even things — down it before it tears itself apart. All you need are a couple of black holes and a few infinitely long cosmic strings.


The wormhole problem

In principle, building a wormhole is pretty straightforward. According to Einstein’s Theory of General Relativity, mass and energy warp the fabric of space-time. And a certain special configuration of matter and energy allows the formation of a tunnel, a shortcut between two otherwise distant portions of the universe.

Related: 8 Ways You Can See Einstein’s Theory of Relativity in Real Life

Unfortunately, even on paper, those wormholes are fantastically unstable. Even a single photon passing through the wormhole triggers a catastrophic cascade that rips the wormhole apart. However, a healthy dose of negative mass — yes, that’s matter but with an opposite weight — can counteract the destabilizing effects of regular matter trying to pass through the wormhole, making it traversable.

OK, matter with negative mass doesn’t exist, so we need a new plan.

Let’s start with the wormhole itself. We need an entrance and an exit. It’s theoretically possible to connect a black hole (a region of space where nothing can escape) to a white hole (a theoretical region of space where nothing can enter). When these two odd creatures join together, they form a brand-new thing: a wormhole. So you can jump into either end of this tunnel and instead of getting crushed into oblivion you just harmlessly waltz out the other side.

Oh, but white holes don’t exist, either. Man, this is getting tricky.

Charge it up

Since white holes don’t exist, we need a new plan. Thankfully, some clever math reveals a possible answer: a charged black hole. Black holes can carry an electric charge (it’s not common because of the way they’re formed naturally, but we’ll take what we can get). The inside of a charged black hole is a strange place, with the normal point-like singularity of a black hole stretched and distorted, allowing it to form a bridge to another oppositely charged black hole.

Voila: a wormhole, using only things that might actually exist.

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.

wormhole illustration

(Image credit: Shutterstock)

Put a cosmic bow on it

So to make this all work we need to make sure the two charged black holes stay safely far away from each other, and make sure the tunnel of the wormhole can hold itself open. A potential solution: cosmic strings.

Cosmic strings are theoretical defects, similar to the cracks that form when ice freezes, in the fabric of space-time. These cosmic leftovers formed in the early, heady days of the first fractions of a second after the Big Bang. They are truly exotic objects, no wider than a proton but with a single inch of their length outweighing Mount Everest. You never want to encounter one yourself, since they would slice you clean in half like a cosmic lightsaber, but you don’t have to worry much since we’re not even sure they exist, and we’ve never seen one out there in the universe.

Still, there’s no reason they can’t exist, so they’re fair game.

They have another very useful property when it comes to wormholes: enormous tension. In other words, they really don’t like being pushed around. If you thread the wormhole with a cosmic string, and allow the string to pass along the outside edges of the black holes and stretch out of either end all the way to infinity, then the tension in the string prevents the charged black holes from being attracted to each other, holding the two ends of the wormhole far away from each other. Essentially, the distant ends of the cosmic string act like two opposing tug-of-war teams, holding back the black holes.

Calming the tremors

One cosmic string solves one of the problems (holding the ends open), but it doesn’t prevent the wormhole itself from collapsing if you were to actually use it. So, let’s toss in another cosmic string, also threading the wormhole, but also looping it through normal space between the two black holes.

When cosmic strings are closed in a loop, they wiggle — a lot. These vibrations churn the very fabric of space-time around them, and when tuned just right the vibrations can cause the energy of space in their vicinity to go negative, effectively acting like negative mass within the wormhole, potentially stabilizing it.

It seems a little complex, but in the recent paper, a team of theoretical physicists gave step-by-step instructions for constructing just such a wormhole. It’s not a perfect solution: Eventually the inherent vibrations in the cosmic strings — the same ones that might keep the wormhole open — pull energy, and therefore mass, away from the string, making it smaller and smaller. Essentially, over time the cosmic strings wiggle themselves into oblivion, with complete collapse of the wormhole not far behind. But the kludged-together wormhole may stay stable long enough to allow messages or even objects to travel down the tunnel and actually not die, which is nice.

But first we need to find some cosmic strings.

Paul M. Sutter is an astrophysicist at The Ohio State University, host of Ask a Spaceman and Space Radio, and author of Your Place in the Universe.

Originally published on Live Science.

Experts warn a huge quake is the greatest threat facing Israel



After tremors, experts warn a huge quake is the greatest threat facing Israel

Scientists say thousands could die because Israel, which sits on a major fault line, has ignored warnings to strengthen homes and schools

IDF soldiers search for survivors in a building that collapsed during an earthquake that struck Mexico on September 24, 2017. (Israel Defense Forces)

IDF soldiers search for survivors in a building that collapsed during an earthquake that struck Mexico on September 24, 2017. (Israel Defense Forces)

After a series of minor tremors rattled northern Israel over the last two weeks, experts warned that the country is negligently unprepared for a major earthquake that would likely kill thousands of people, including many children.

“The threat of an earthquake, is in my eyes, the greatest threat facing the state of Israel,” geologist Ariel Heimann told Hadashot news on Friday. “It is definitely a greater threat than the Qassam [rockets] fired from Gaza, and it is a far greater danger than the Iranian threat.”

Israel sits on the Syrian-African rift, a tear in the earth’s crust running the length of the border separating Israel and Jordan, and is part of the Great Rift Valley, which extends from northern Syria to Mozambique.

The last major earthquake to hit the region was in 1927 — a 6.2-magnitude tremor that killed 500 people and injured another 700. And experts have warned Israel is due for a major quake in the near future.

“If, God forbid, we have an earthquake like this, it will leave thousands dead and hundreds of thousands of people will have to leave their homes. Houses will be destroyed, there will be massive economic damage that will set the country back dozens of years,” Heimann warned.

Another expert said school children were particularly vulnerable, pointing to a recent report that out of 1,600 schools deemed to be in danger of collapsing in a survey three years ago, just 53 have since been reinforced.

Schoolchildren taking part in a Home Front drill, simulating an earthquake, at a Jerusalem school on February 20, 2012 (photo credit: Uri Lenz/Flash90)

School children taking part in a Home Front drill, simulating an earthquake, at a Jerusalem school on February 20, 2012 (photo credit: Uri Lenz/Flash90)

“In Haiti 38,000 children died, in China more than 10,000 children were among the 120,000 killed, in Pakistan it was 17,000 among 83,000 dead — do people understand this?” asked Ephraim Leor, an expert on mass casualty disasters. “We could lose an entire generation between the ages of 6 and 18.”

Col. Itzik Bar from the IDF’s Home Front Command, put expected casualties from a major quake at 7,000 dead and 200,000 homeless.

“Apparently it will unfortunately take a mid-sized quake with 100-200 casualties to make this country wake up and seriously prepare,” he told Hadashot.

A minor earthquake hit northern Israel on Monday evening, bringing the number of tremors in the area in recent days to more than 40, further fueling fears that a major earthquake could be on its way.

View of damage caused to houses in northern Israel, after earthquakes shook the area, on July 9, 2018. (David Cohen/Flash90)

The epicenter of the 3.2 quake was at the northern edge of the Sea of Galilee, similar to the previous ones. It hit at 6:15 p.m. without causing damage or casualties.

But despite the looming threat, new details show that the government has been making very little progress in preparing for a strong tremor and strengthening structures.

None of the 108 dangerous material factories, ordered two years ago by the Ministry of Environmental Protection to strengthen their structures, has completed the process, an earlier Hadashot news report said. Only one factory has presented a plan to implement the decision. The ministry said it was behind schedule, due to a “severe shortage of manpower.”

A nationwide early warning system approved in 2012 only began its deployment a year ago. The Geological Survey of Israel has only deployed 55 of the 120 alert stations, none of which are operational.

But sounding dire warnings appears to have little effect. Previous warnings have fallen on deaf ears.

A State Comptroller report in 2001 found that no funding had been allocated for strengthening buildings and infrastructure. It was followed by another report in 2004, which said that not much had been done in the intervening years, due to spats between ministries over responsibility for the work.

An inter-ministerial committee set up in 2004 proposed making preparations for a 7.5 magnitude quake to the country’s north, with catastrophic loss of life and severe damage to infrastructure. It raised the prospect of 16,000 dead and nearly 100,000 wounded in such an event, with 10,000 buildings destroyed.

In 2011, another state comptroller report sounded further warnings about the threat to northern communities and infrastructure from an earthquake, and once again lamented the dearth of precautionary measures taken.

Defense Minister Avigdor Liberman announced last week that a new multi-year plan to protect Israel from earthquakes will be presented to the cabinet this month.