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Post by auntym on Mar 30, 2014 12:28:54 GMT -6
www.bbc.com/future/story/20140326-will-we-ever-travel-in-wormholes 26 March 2014
Will we ever… travel in wormholes?By Marcus Woo (SPL) Leaping between galaxies through tunnels in space may sound crazy, but physicists have yet to rule it out. So how could this possibly work, asks Marcus Woo. The universe is huge. Travelling at light speed to the nearest star would take more than four years. Venturing to the other side of the galaxy? More than 100,000 years. So what's an intrepid space traveller to do? One option is a cosmic shortcut called a wormhole, a tunnel through the fabric of space and time that can connect far-flung corners of the universe. It’s the chosen route of many fictional space travellers, including the characters in the upcoming film Interstellar, directed by Christopher Nolan. Hopping through a wormhole would be incredibly difficult, say scientists, but they have yet to rule it out. So, what would it take in reality, and what exactly is stopping us now? To picture a wormhole, imagine that the universe is a two-dimensional sheet. Poke two holes and curve the sheet around them to form two funnels. Stitch the ends of the funnels together, and you get a wormhole-like tube (see below). Rather than take the long route across space (pink line), a wormhole allows a shortcut through space and time (blue funnel) (Detlev van Ravenswaay/SPL) Rather than take the long route across space (pink line), a wormhole allows a shortcut through space and time (blue funnel) (Detlev van Ravenswaay/SPL) Manipulating space in this way means you can jump into one end of a wormhole, travel a short distance, and pop out from the other end in another galaxy. The mouth of a wormhole also acts as a cosmic window, allowing you to gaze at the stars on the opposite end of the universe. That’s the theory anyway. What does the science say about the feasibility of such travel? CONTINUE READING: www.bbc.com/future/story/20140326-will-we-ever-travel-in-wormholes
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Post by auntym on Jul 11, 2017 13:40:13 GMT -6
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Post by swamprat on Oct 24, 2017 14:29:23 GMT -6
Read carefully; this will be covered on your final exam.....Newfound Wormhole Allows Information to Escape Black HolesPhysicists theorize that a new “traversable” kind of wormhole could resolve a baffling paradox and rescue information that falls into black holes.
Natalie Wolchover, Senior Writer October 23, 2017
In 1985, when Carl Sagan was writing the novel Contact, he needed to quickly transport his protagonist Dr. Ellie Arroway from Earth to the star Vega. He had her enter a black hole and exit light-years away, but he didn’t know if this made any sense. The Cornell University astrophysicist and television star consulted his friend Kip Thorne, a black hole expert at the California Institute of Technology (who won a Nobel Prize earlier this month). Thorne knew that Arroway couldn’t get to Vega via a black hole, which is thought to trap and destroy anything that falls in. But it occurred to him that she might make use of another kind of hole consistent with Albert Einstein’s general theory of relativity: a tunnel or “wormhole” connecting distant locations in space-time.
While the simplest theoretical wormholes immediately collapse and disappear before anything can get through, Thorne wondered whether it might be possible for an “infinitely advanced” sci-fi civilization to stabilize a wormhole long enough for something or someone to traverse it. He figured out that such a civilization could in fact line the throat of a wormhole with “exotic material” that counteracts its tendency to collapse. The material would possess negative energy, which would deflect radiation and repulse space-time apart from itself. Sagan used the trick in Contact, attributing the invention of the exotic material to an earlier, lost civilization to avoid getting into particulars. Meanwhile, those particulars enthralled Thorne, his students and many other physicists, who spent years exploring traversable wormholes and their theoretical implications. They discovered that these wormholes can serve as time machines, invoking time-travel paradoxes — evidence that exotic material is forbidden in nature.
Now, decades later, a new species of traversable wormhole has emerged, free of exotic material and full of potential for helping physicists resolve a baffling paradox about black holes. This paradox is the very problem that plagued the early draft of Contact and led Thorne to contemplate traversable wormholes in the first place; namely, that things that fall into black holes seem to vanish without a trace. This total erasure of information breaks the rules of quantum mechanics, and it so puzzles experts that in recent years, some have argued that black hole interiors don’t really exist — that space and time strangely end at their horizons.
The flurry of findings started last year with a paper that reported the first traversable wormhole that doesn’t require the insertion of exotic material to stay open. Instead, according to Ping Gao and Daniel Jafferis of Harvard University and Aron Wall of Stanford University, the repulsive negative energy in the wormhole’s throat can be generated from the outside by a special quantum connection between the pair of black holes that form the wormhole’s two mouths. When the black holes are connected in the right way, something tossed into one will shimmy along the wormhole and, following certain events in the outside universe, exit the second. Remarkably, Gao, Jafferis and Wall noticed that their scenario is mathematically equivalent to a process called quantum teleportation, which is key to quantum cryptography and can be demonstrated in laboratory experiments.
John Preskill, a black hole and quantum gravity expert at Caltech, says the new traversable wormhole comes as a surprise, with implications for the black hole information paradox and black hole interiors. “What I really like,” he said, “is that an observer can enter the black hole and then escape to tell about what she saw.” This suggests that black hole interiors really exist, he explained, and that what goes in must come out.
Lucy Reading-Ikkanda/Quanta Magazine
A Cryptic Equation The new wormhole work began in 2013, when Jafferis attended an intriguing talk at the Strings conference in South Korea. The speaker, Juan Maldacena, a professor of physics at the Institute for Advanced Study in Princeton, New Jersey, had recently concluded, based on various hints and arguments, that “ER = EPR.” That is, wormholes between distant points in space-time, the simplest of which are called Einstein-Rosen or “ER” bridges, are equivalent (albeit in some ill-defined way) to entangled quantum particles, also known as Einstein-Podolsky-Rosen or “EPR” pairs. The ER = EPR conjecture, posed by Maldacena and Leonard Susskind of Stanford, was an attempt to solve the modern incarnation of the infamous black hole information paradox by tying space-time geometry, governed by general relativity, to the instantaneous quantum connections between far-apart particles that Einstein called “spooky action at a distance.”
The paradox has loomed since 1974, when the British physicist Stephen Hawking determined that black holes evaporate — slowly giving off heat in the form of particles now known as “Hawking radiation.” Hawking calculated that this heat is completely random; it contains no information about the black hole’s contents. As the black hole blinks out of existence, so does the universe’s record of everything that went inside. This violates a principle called “unitarity,” the backbone of quantum theory, which holds that as particles interact, information about them is never lost, only scrambled, so that if you reversed the arrow of time in the universe’s quantum evolution, you’d see things unscramble into an exact re-creation of the past.
Almost everyone believes in unitarity, which means information must escape black holes — but how? In the last five years, some theorists, most notably Joseph Polchinski of the University of California, Santa Barbara, have argued that black holes are empty shells with no interiors at all — that Ellie Arroway, upon hitting a black hole’s event horizon, would fizzle on a “firewall” and radiate out again.
Many theorists believe in black hole interiors (and gentler transitions across their horizons), but in order to understand them, they must discover the fate of information that falls inside. This is critical to building a working quantum theory of gravity, the long-sought union of the quantum and space-time descriptions of nature that comes into sharpest relief in black hole interiors, where extreme gravity acts on a quantum scale.
The quantum gravity connection is what drew Maldacena, and later Jafferis, to the ER = EPR idea, and to wormholes. The implied relationship between tunnels in space-time and quantum entanglement posed by ER = EPR resonated with a popular recent belief that space is essentially stitched into existence by quantum entanglement. It seemed that wormholes had a role to play in stitching together space-time and in letting black hole information worm its way out of black holes — but how might this work? When Jafferis heard Maldacena talk about his cryptic equation and the evidence for it, he was aware that a standard ER wormhole is unstable and non-traversable. But he wondered what Maldacena’s duality would mean for a traversable wormhole like the ones Thorne and others played around with decades ago. Three years after the South Korea talk, Jafferis and his collaborators Gao and Wall presented their answer. The work extends the ER = EPR idea by equating, not a standard wormhole and a pair of entangled particles, but a traversable wormhole and quantum teleportation: a protocol discovered in 1993 that allows a quantum system to disappear and reappear unscathed somewhere else.
When Maldacena read Gao, Jafferis and Wall’s paper, “I viewed it as a really nice idea, one of these ideas that after someone tells you, it’s obvious,” he said. Maldacena and two collaborators, Douglas Stanford and Zhenbin Yang, immediately began exploring the new wormhole’s ramifications for the black hole information paradox; their paper appeared in April. Susskind and Ying Zhao of Stanford followed this with a paper about wormhole teleportation in July. The wormhole “gives an interesting geometric picture for how teleportation happens,” Maldacena said. “The message actually goes through the wormhole.”
See next post for page 2
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Post by swamprat on Oct 24, 2017 14:31:16 GMT -6
Page 2
Diving Into Wormholes In their paper, “Diving Into Traversable Wormholes,” published in Fortschritte der Physik, Maldacena, Stanford and Yang consider a wormhole of the new kind that connects two black holes: a parent black hole and a daughter one formed from half of the Hawking radiation given off by the parent as it evaporates. The two systems are as entangled as they can be. Here, the fate of the older black hole’s information is clear: It worms its way out of the daughter black hole.
During an interview this month in his tranquil office at the IAS, Maldacena, a reserved Argentinian-American with a track record of influential insights, described his radical musings. On the right side of a chalk-dusty blackboard, Maldacena drew a faint picture of two black holes connected by the new traversable wormhole. On the left, he sketched a quantum teleportation experiment, performed by the famous fictional experimenters Alice and Bob, who are in possession of entangled quantum particles a and b, respectively. Say Alice wants to teleport a qubit q to Bob. She prepares a combined state of q and a,measures that combined state (reducing it to a pair of classical bits, 1 or 0), and sends the result of this measurement to Bob. He can then use this as a key for operating on b in a way that re-creates the state q. Voila, a unit of quantum information has teleported from one place to the other.
Maldacena turned to the right side of the blackboard. “You can do operations with a pair of black holes that are morally equivalent to what I discussed [about quantum teleportation]. And in that picture, this message really goes through the wormhole.”
Say Alice throws qubit q into black hole A. She then measures a particle of its Hawking radiation, a, and transmits the result of the measurement through the external universe to Bob, who can use this knowledge to operate on b, a Hawking particle coming out of black hole B. Bob’s operation reconstructs q, which appears to pop out of B, a perfect match for the particle that fell into A. This is why some physicists are excited: Gao, Jafferis and Wall’s wormhole allows information to be recovered from black holes. In their paper, they set up their wormhole in a negatively curved space-time geometry that often serves as a useful, if unrealistic, playground for quantum gravity theorists. However, their wormhole idea seems to extend to the real world as long as two black holes are coupled in the right way: “They have to be causally connected and then the nature of the interaction that we took is the simplest thing you can imagine,” Jafferis explained. If you allow the Hawking radiation from one of the black holes to fall into the other, the two black holes become entangled, and the quantum information that falls into one can exit the other.
The quantum-teleportation format precludes using these traversable wormholes as time machines. Anything that goes through the wormhole has to wait for Alice’s message to travel to Bob in the outside universe before it can exit Bob’s black hole, so the wormhole doesn’t offer any superluminal boost that could be exploited for time travel. It seems traversable wormholes might be permitted in nature as long as they offer no speed advantage. “Traversable wormholes are like getting a bank loan,” Gao, Jafferis and Wall wrote in their paper: “You can only get one if you are rich enough not to need it.”
A Naive Octopus While traversable wormholes won’t revolutionize space travel, according to Preskill the new wormhole discovery provides “a promising resolution” to the black hole firewall question by suggesting that there is no firewall at black hole horizons. Preskill said the discovery rescues “what we call ‘black hole complementarity,’ which means that the interior and exterior of the black hole are not really two different systems but rather two very different, complementary ways of looking at the same system.” If complementarity holds, as is widely assumed, then in passing across a black hole horizon from one realm to the other, Contact’s Ellie Arroway wouldn’t notice anything strange. This seems more likely if, under certain conditions, she could even slide all the way through a Gao-Jafferis-Wall wormhole.
The wormhole also safeguards unitarity — the principle that information is never lost — at least for the entangled black holes being studied. Whatever falls into one black hole eventually exits the other as Hawking radiation, Preskill said, which “can be thought of as in some sense a very scrambled copy of the black hole interior.”
Taking the findings to their logical conclusion, Preskill thinks it ought to be possible (at least for an infinitely advanced civilization) to influence the interior of one of these black holes by manipulating its radiation. This “sounds crazy,” he wrote in an email, but it “might make sense if we can think of the radiation, which is entangled with the black hole — EPR — as being connected to the black hole interior by wormholes — ER. Then tickling the radiation can send a message which can be read from inside the black hole!” He added, “We still have a ways to go, though, before we can flesh out this picture in more detail.”
Indeed, obstacles remain in the quest to generalize the new wormhole findings to a statement about the fate of all quantum information, or the meaning of ER = EPR.
In Maldacena and Susskind’s paper proposing ER = EPR, they included a sketch that’s become known as the “octopus”: a black hole with tentacle-like wormholes leading to distant Hawking particles that have evaporated out of it. The authors explained that the sketch illustrates “the entanglement pattern between the black hole and the Hawking radiation. We expect that this entanglement leads to the interior geometry of the black hole.”
A sketch known as the “octopus” that expresses the ER = EPR idea. arXiv:1306.0533v2 [hep-th]
But according to Matt Visser, a mathematician and general-relativity expert at Victoria University of Wellington in New Zealand who has studied wormholes since the 1990s, the most literal reading of the octopus picture doesn’t work. The throats of wormholes formed from single Hawking particles would be so thin that qubits could never fit through. “A traversable wormhole throat is ‘transparent’ only to wave packets with size smaller than the throat radius,” Visser explained. “Big wave packets will simply bounce off any small wormhole throat without crossing to the other side.”
Stanford, who co-wrote the recent paper with Maldacena and Yang, acknowledged that this is a problem with the simplest interpretation of the ER = EPR idea, in which each particle of Hawking radiation has its own tentacle-like wormhole. However, a more speculative interpretation of ER = EPR that he and others have in mind does not suffer from this failing. “The idea is that in order to recover the information from the Hawking radiation using this traversable wormhole,” Stanford said, one has to “gather the Hawking radiation together and act on it in a complicated way.” This complicated collective measurement reveals information about the particles that fell in; it has the effect, he said, of “creating a large, traversable wormhole out of the small and unhelpful octopus tentacles. The information would then propagate through this large wormhole.” Maldacena added that, simply put, the theory of quantum gravity might have a new, generalized notion of geometry for which ER equals EPR. “We think quantum gravity should obey this principle,” he said. “We view it more as a guide to the theory.”
In his 1994 popular science book, Black Holes and Time Warps, Kip Thorne celebrated the style of reasoning involved in wormhole research. “No type of thought experiment pushes the laws of physics harder than the type triggered by Carl Sagan’s phone call to me,” he wrote; “thought experiments that ask, ‘What things do the laws of physics permit an infinitely advanced civilization to do, and what things do the laws forbid?’”
www.quantamagazine.org/newfound-wormhole-allows-information-to-escape-black-holes-20171023/
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Post by swamprat on Nov 9, 2018 10:25:24 GMT -6
IF they exist, they MIGHT look like THIS! Go ahead... Jump in and find out!Ripples in Space-Time Could Reveal the Shape of WormholesBy Mindy Weisberger, Senior Writer | November 7, 2018
Wormholes are often pictured as yawning holes in space joined by a narrow tunnel, but a new study presents the first equation for calculating the objects' geometric shape. Credit: Shutterstock
Wormholes — yawning gateways that could theoretically connect distant points in space-time — are usually illustrated as gaping gravity wells linked by a narrow tunnel.
But their precise shape has been unknown.
Now, however, a physicist in Russia has devised a method to measure the shape of symmetric wormholes — even though they have not been proven to exist — based on the way the objects may affect light and gravity.
In theory, traversable wormholes, or four-dimensional portals through space-time, might work something like this: At one end, the irresistible pull of a black hole would suck matter into a tunnel connected at the other end to a "white hole," which would spit matter out at a location far away from the material's point of origin in space and time, TK said. Though scientists have observed evidence of black holes in the universe, white holes have never been found.
Wormholes (and the possibility of interstellar travel that they suggest) thus remain unproven, though Albert Einstein's theory of general relativity leaves room for the objects' existence.
However, even though wormholes may or may not exist, scientists do know a lot about the behavior of light and gravitational waves. The latter are the ripples in space-time that swirl around massive objects such as black holes.
One wormhole property that could be observed, albeit indirectly, is a redshift in the light near the object, the new study said. (Redshifting is a decrease in the frequency of light wavelengths as they travel away from an object, resulting in a shift to the red part of the spectrum.)
If you know how light around a potential wormhole is redshifted, you can then use the frequencies of gravitational waves, or how often they oscillate, to predict the symmetrical wormhole's shape, said study author Roman Konoplya. He is an associate professor with the Institute of Gravitation and Cosmology at the Peoples' Friendship University of Russia (RUDN).
Typically, researchers work the other way around, looking at the geometry of known shapes to calculate how light and gravity behave, Konoplya told Live Science in an email.
There would be a couple of methods for checking the redshift near a potential wormhole, Konoplya said. One would use gravitational lensing, or the bending of light rays as they pass by massive objects — like, possibly, wormholes. This lensing would be measured in its effects on faint light coming from distant stars (or on brighter light from a nearby star "if we are very, very lucky," Konoplya said). Another method would measure the electromagnetic radiation near the wormhole as it attracts more matter, he explained.
Think of the equation this way: If you strike a drum, the behavior of sound waves produced by the vibration of the taut skin can reveal the drum's shape, Jolyon Bloomfield, a lecturer in the physics department at the Massachusetts Institute of Technology, told Live Science.
"All the different frequencies — that tells you the different vibrational modes of that taut skin," Bloomfield said. Meanwhile, the peaks and valleys of those vibrations gradually decay in time, which shows how the modes are "damped." Those two pieces of information together can help you define the shape of the drum, Bloomfield said.
"What this paper is doing is kind of the same thing for a wormhole. If we are actually able to 'listen' to decaying frequencies of oscillation of a wormhole with enough precision, we can infer the shape of the wormhole by the spectrum of the frequencies and how fast they decay," he explained.
In his equation, Konoplya took a wormhole's redshift values and then incorporated quantum mechanics, or the physics of tiny subatomic particles, to estimate how gravitational ripples in space-time would affect the wormhole's electromagnetic waves. From there, he constructed an equation to calculate a wormhole's geometric shape and mass, he reported in the study.
The technology for measuring gravitational waves has been around only since 2015, with the introduction of the Laser Interferometer Gravitational-Wave Observatory (LIGO). Now, researchers seek to fine-tune LIGO measurements, as better data could help scientists finally determine if there is exotic matter in the universe — matter made of building blocks unlike normal atomic particles. That material could support objects like wormholes, Bloomfield told Live Science.
For now, at least, wormholes are only theoretical, so Konoplya's equation doesn't represent any actual real-world measurements, he wrote in the email. And detectors like LIGOmeasure only one frequency of gravitational waves, while you would need several frequencies to predict a wormhole's shape, Konoplya said.
"From such poor data, it is impossible to extract enough information for such a complex thing as a geometry of a compact object," Konoplya wrote in the email.
Future studies could provide an even more detailed view of a wormhole's shape and properties, Konoplya said.
"Our results may be applied to rotating wormholes as well, provided they are symmetrical enough," he added.
The findings were published online Sept. 10 in the journal Physics Letters B.
www.livescience.com/64033-shape-of-a-wormhole.html
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Post by Deleted on Jul 4, 2019 6:19:03 GMT -6
Lockheed Martin Space Systems developed a rocket to open a wormhole,technology from Tesla,Nikola Tesla. ... caused a fluctuation in space and time opening multiple wormholes,one explanation on how ufos make it into our universe.
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Post by auntym on Dec 11, 2019 14:14:54 GMT -6
www.astronomy.com/news/2019/07/if-wormholes-exist-could-we-really-travel-through-them?utm_source=asytwitter&utm_medium=social&utm_campaign=asytwitter If wormholes exist, could we really travel through them? The ultimate cosmic shortcuts could make space travel easier. But do they exist?By Bill Andrews / www.astronomy.com/authors/bill-andrews Wednesday, July 31, 2019 Wormholes could offer a path to the most distant places in the universe. dimonika/Shutterstock Wormholes make the best shortcuts in the universe. That’s true in a literal sense, since the theoretical things can connect distant corners of the cosmos (or even different universes), allowing a traveler to go someplace without having to visit everywhere in between. But wormholes also present the perfect way for writers to get around that pesky speed of light, the universe’s speed limit and impediment to fast travel through the cosmos. If characters in science fiction aren’t taking months or years to travel between worlds, a wormhole is likely the reason. Too bad, then, that as far as we know, the things don’t exist. Historical Holes Oh, wormholes could exist. We just don’t know whether they actually do. Or, for that matter, if they’d be useful to us as potential shortcuts. But ever since Albert Einstein published his general theory of relativity, we’ve had the mathematical language for describing and imagining these fantastical structures. Back then, though, scientists referred to them as “one-dimensional tubes” and simply “bridges” — in fact, the term “Einstein-Rosen bridge” is still used semi-interchangeably with “wormhole” (the “Rosen” being Israeli physicist Nathan Rosen). It was American physicist John Wheeler who coined the vermicular vernacular in a 1957 Annals of Physics paper: “This analysis forces one to consider situations,” he wrote, “where there is a net flux of lines of force, through what topologists would call ‘a handle’ of the multiply-connected space, and what physicists might perhaps be excused for more vividly terming a ‘wormhole’.” Tantalizing Physics It’s a lucky thing, because that vivid name helps describe just what the heck we’re talking about. The curvature of space and lines of force might not mean much to most people, but who can’t imagine a worm eating its way through an apple or piece of timber? The resulting tunnel, connecting one part of the surface with another more distant part, is the perfect metaphor for something that can connect otherwise remote locations in the universe. And, because Einstein also showed that space and time are fundamentally interconnected, traveling through a wormhole might not only take us to another far-away place, but it could even serve as a shortcut to another time. No wonder, then, that they’ve become so popular in science fiction. In real life, the speed of light is the end of the line: Nothing with mass can ever accelerate faster. That means sunlight takes over 5 hours to get to Pluto and years to reach other star systems. And it’s the rare story that benefits from forcing its characters to sit around waiting years to get anywhere. Wormholes, thus, are the perfect way to bypass Einstein’s speed limit, and get your heroes and villains to travel the galaxy in a reasonable time frame. Plus, they allow for the element of time travel to enter the story, all without breaking any laws of physics. So, the real question is: Can actual people take advantage of wormholes too? The answer is… maybe? CONTINUE READING: www.astronomy.com/news/2019/07/if-wormholes-exist-could-we-really-travel-through-them?utm_source=asytwitter&utm_medium=social&utm_campaign=asytwitter
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WORMHOLES
Dec 14, 2019 10:05:56 GMT -6
via mobile
Post by jcurio on Dec 14, 2019 10:05:56 GMT -6
Lockheed Martin Space Systems developed a rocket to open a wormhole,technology from Tesla,Nikola Tesla. ... caused a fluctuation in space and time opening multiple wormholes,one explanation on how ufos make it into our universe. Watch again!!
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