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Physicists Create ‘the Smallest, Crummiest Wormhole You Can Imagine’

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In an experiment that ticks most of the mystery boxes in modern physics, a group of researchers announced on Wednesday that they had simulated a pair of black holes in a quantum computer and sent a message between them through a shortcut in space-time called a wormhole.

Physicists described the achievement as another small step in the effort to understand the relation between gravity, which shapes the universe, and quantum mechanics, which governs the subatomic realm of particles.

“This is important because what we have here in its construct and structure is a baby wormhole,” said Maria Spiropulu, a physicist at the California Institute of Technology and the leader of a consortium called Quantum Communication Channels for Fundamental Physics, which conducted the research. “And we hope that we can make adult wormholes and toddler wormholes step-by-step.”

In their report, published Wednesday in Nature, the researchers described the result in measured words: “This work is a successful attempt at observing traversable wormhole dynamics in an experimental setting.”

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The wormhole that Dr. Spiropulu and her colleagues created and exploited is not a tunnel through real physical space but rather through an “emergent” two-dimensional space. The “black holes” were not real ones that could swallow the computer but lines of code in a quantum computer. Strictly speaking, the results apply only to a simplified “toy model” of a universe — in particular, one that is akin to a hologram, with quantum fields on the edge of space-time determining what happens within, sort of in the way that the label on a soup can describes the contents.

To be clear: The results of this experiment do not offer the prospect anytime soon, if ever, of a cosmic subway through which to roam the galaxy like Jodie Foster in the movie “Contact” or Matthew McConaughey in “Interstellar.”

“I guess the key question, which is perhaps hard to answer, is: Do we say from the simulation it’s a real black hole?” Daniel Jafferis, a physics professor at Harvard, said. “I kind of like the term ‘emergent black hole.’”

He added: “We are just using the quantum computer to find out what it would look and feel like if you were in this gravitational situation.” He and Alexander Zlokapa, a doctoral student at the Massachusetts Institute of Technology, are the lead authors of the paper.

Physicists reacted to the paper with interest and caution, expressing concern that the public and media would mistakenly think that actual physical wormholes had been created.

“The most important thing I’d want New York Times readers to understand is this,” Scott Aaronson, a quantum computing expert at the University of Texas in Austin, wrote in an email. “If this experiment has brought a wormhole into actual physical existence, then a strong case could be made that you, too, bring a wormhole into actual physical existence every time you sketch one with pen and paper.”

Daniel Harlow, a physicist at M.I.T. who was not involved in the experiment, noted that the experiment was based on a model of quantum gravity that was so simple, and unrealistic, that it could just as well have been studied using a pencil and paper.

“So I’d say that this doesn’t teach us anything about quantum gravity that we didn’t already know,” Dr. Harlow wrote in an email. “On the other hand, I think it is exciting as a technical achievement, because if we can’t even do this (and until now we couldn’t), then simulating more interesting quantum gravity theories would CERTAINLY be off the table.” Developing computers big enough to do so might take 10 or 15 years, he added.

Leonard Susskind, a physicist at Stanford University who was not part of the team, agreed. “They’re learning that they could do this experiment,” he said, adding: “The really interesting thing here is the possibility of analyzing purely quantum phenomena using general relativity, and who knows where that’s going to go.”

Albert Einstein at the Carnegie Institute of Technology, now known as Carnegie Mellon University, in Pittsburgh in 1934.Pictorial Press Ltd., via Alamy

Wormholes entered the physics lexicon in 1935 as one of the weirder predictions of Albert Einstein’s general theory of relativity, which describes how matter and energy warp space to create what we call gravity. That year Einstein and his colleague, Nathan Rosen, showed in a paper that shortcuts through space-time, connecting pairs of black holes, could exist. The physicist John Wheeler later called these connectors “wormholes.”

Originally it seemed that wormholes were effectively useless; theory held that they would slam shut the instant anything entered them. They have never been observed outside of science fiction.

A month earlier that same year, in 1935, Einstein, Rosen and Boris Podolsky made another breakthrough, one they thought would discredit the chancy nature of quantum mechanics. They pointed out that quantum rules permitted what Einstein called “spooky action at a distance.” Measuring one of a pair of particles would determine the results of measuring the other particle, even if the two were light-years apart. Einstein thought this prediction was absurd, but physicists now call it “entanglement” and use it every day in the lab.

Until a few years ago, such quantum tricks weren’t thought to have anything to do with gravity. As a result, physicists were left with no theory of “quantum gravity” to explain what happened when the realms of inner space and outer space collided, as in the Big Bang or inside black holes.

But in 2013 Juan Maldacena, a theoretical physicist at the Institute for Advanced Study in Princeton, and Dr. Susskind proposed that these two phenomena — spooky action and wormholes — were actually two sides of the same coin, each described in a different but complementary mathematical language.

Those spooky, entangled particles, by this logic, were connected by equally mysterious wormholes. Quantum mechanics could be enlisted to study gravity, and vice versa. The equations that describe quantum phenomena turned out to have analogues in the Einsteinian equations for gravity.

“It’s mostly a matter of taste which description you use because they give exactly the same answer,” Dr. Jafferis said. “And that was an incredible discovery.”

In a quantum computer, physicists use a circuit of operations called gates to open a shortcut in an imaginary space between qubits representing two black holes and send messages between them.Andrew Mueller/INQNET

The recent wormhole experiment sought to employ the mathematics of general relativity to examine an aspect of quantum magic, known as quantum teleportation, to see if some new aspect of physics or gravity might be revealed.

In quantum teleportation, physicists use a set of quantum manipulations to send information between two particles — inches or miles apart — that are entangled in a pair, without the physicists knowing what the message is. The technology is expected to be the heart of a next-generation, unhackable “quantum internet.”

Physicists like to compare the teleportation process to two cups of tea. Drop a cube of sugar into one teacup, and it promptly dissolves — then, after a tick of the quantum clock, the cube reappears intact in the other teacup.

The experiment became conceivable after a pair of papers by Dr. Susskind and, independently, by Dr. Jafferis, Ping Gao of M.I.T., and Aron Wall, a theoretical physicist at the University of Cambridge. They suggested a way that wormholes could be made traversable, after all. What was needed, Dr. Gao and his collaborators said, was a small dose of negative energy at the exit end of the wormhole to prop open the hatch long enough for information to escape.

In classical physics, there is no such thing as negative energy. But in quantum theory, energy can be negative, generating an antigravitational effect. For example, so-called virtual particles, which flit in and out of existence using energy borrowed from empty space, can fall into a black hole, carrying a debt to nature in the form of energy that the black hole must then pay back. This slow leak, Stephen Hawking calculated in 1974, causes the black hole to lose energy and shrink.

When Dr. Spiropulu proposed trying to recreate this wormhole magic on a quantum computer, her colleagues and sponsors at the Department of Energy “thought I was completely nuts,” she recalled. “But Jafferis said, Let’s do it.”

One clue that the researchers were actually recording “wormholelike” behavior was that signals emerged from the other end of the wormhole in the order that they went in.Andrew Mueller/INQNET

In ordinary computers, including the phone in your pocket, the currency of calculation is bits, which can be ones or zeros. Quantum computers run on qubits, which can be 0 or 1 or anywhere in between until they are measured or observed. This makes quantum computers super powerful for certain kinds of tasks, like factoring large numbers and (maybe one day) cracking cryptographic codes. In essence, a quantum computer runs all the possible variations of the program simultaneously to arrive at a solution.

“We make uncertainty an ally and embrace it,” Dr. Spiropulu said.

To reach their full potential, quantum computers will need thousands of working qubits and a million more “error correction” qubits. Google hopes to reach such a goal by the end of the decade, according to Hartmut Neven, head of the company’s Quantum Artificial Intelligence lab in Venice, Calif., who is also on Dr. Spiropulu’s team.

The Caltech physicist and Nobel laureate Richard Feynman once predicted that the ultimate use of this quantum power might be to investigate quantum physics itself, as in the wormhole experiment.

“I’m excited to see that researchers can live out Feynman’s dream,” Dr. Neven said.

The wormhole experiment was carried out on a version of Google’s Sycamore 2 computer, which has 72 qubits. Of these, the team used only nine to limit the amount of interference and noise in the system. Two were reference qubits, which played the roles of input and output in the experiment.

The seven other qubits held the two copies of code describing a “sparsified” version of an already simple model of a holographic universe called SYK, named after its three creators: Subir Sachdev of Harvard, Jinwu Ye of Mississippi State University and Alexei Kitaev of Caltech. Both SYK models were packed into the same seven qubits. In the experiment these SYK systems played the role of two black holes, one by scrambling the message into nonsense — the quantum equivalent of swallowing it — and then the other by popping it back out.

“Into this we throw a qubit,” Dr. Lykken said, referring to the input message — the quantum analog of a series of ones and zeros. This qubit interacted with the first copy of the SYK qubit; its meaning was scrambled into random noise and it disappeared.

Then, in a tick of the quantum clock, the two SYK systems were connected and a shock of negative energy went from the first system to the second one, briefly propping open the latter.

The signal then reappeared in its original unscrambled form — in the ninth and last qubit, attached to the second SYK system, which represented the other end of the wormhole.

One clue that the researchers were actually recording “wormholelike” behavior, Dr. Lykken said, was that signals emerged from the other end of the wormhole in the order that they went in.

In a Nature article accompanying Dr. Jafferis’s paper, Dr. Susskind and Adam Brown, a physicist at Stanford, noted that the results might shed light on some still-mysterious aspects of ordinary quantum mechanics. For instance, after the sugar cube dissolves in the first teacup, why does it reappear in the other cup in its original form?

“The surprise is not that the message made it across in some form, but that it made it across unscrambled,” the two authors wrote.

The easiest explanation, they added, is that the message went through a wormhole, albeit a “really short” one, Dr. Lykken said in an interview. In quantum mechanics, the shortest conceivable length in nature is 10³³ centimeters, the so-called Planck length. Dr. Lykken calculated that their wormhole was maybe only three Planck lengths long.

“It’s the smallest, crummiest wormhole you can imagine making,” he said. “But that’s really cool because now we’re clearly doing quantum gravity.”

 

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Future Space Telescopes Could be 100 Meters Across, Constructed in Space, and Then Bent Into a Precise Shape – Universe Today

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It is an exciting time for astronomers and cosmologists. Since the James Webb Space Telescope (JWST), astronomers have been treated to the most vivid and detailed images of the Universe ever taken. Webb‘s powerful infrared imagers, spectrometers, and coronographs will allow for even more in the near future, including everything from surveys of the early Universe to direct imaging studies of exoplanets. Moreover, several next-generation telescopes will become operational in the coming years with 30-meter (~98.5 feet) primary mirrors, adaptive optics, spectrometers, and coronographs.

Even with these impressive instruments, astronomers and cosmologists look forward to an era when even more sophisticated and powerful telescopes are available. For example, Zachary Cordero 
of the Massachusetts Institute of Technology (MIT) recently proposed a telescope with a 100-meter (328-foot) primary mirror that would be autonomously constructed in space and bent into shape by electrostatic actuators. His proposal was one of several concepts selected this year by the NASA Innovative Advanced Concepts (NIAC) program for Phase I development.

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Corder is the Boeing Career Development Professor in Aeronautics and Astronautics at MIT and a member of the Aerospace Materials and Structures Lab (AMSL) and Small Satellite Center. His research integrates his expertise in processing science, mechanics, and design to develop novel materials and structures for emerging aerospace applications. His proposal is the result of a collaboration with Prof. Jeffrey Lang (from MIT’s Electronics and the Microsystems Technology Laboratories) and a team of three students with the AMSL, including Ph.D. student Harsh Girishbhai Bhundiya.

Their proposed telescope addresses a key issue with space telescopes and other large payloads that are packaged for launch and then deployed in orbit. In short, size and surface precision tradeoffs limit the diameter of deployable space telescopes to the 10s of meters. Consider the recently-launched James Webb Space Telescope (JWST), the largest and most powerful telescope ever sent to space. To fit into its payload fairing (atop an Ariane 5 rocket), the telescope was designed so that it could be folded into a more compact form.

This included its primary mirror, secondary mirror, and sunshield, which all unfolded once the space telescope was in orbit. Meanwhile, the primary mirror (the most complex and powerful ever deployed) measures 6.5 meters (21 feet) in diameter. Its successor, the Large UV/Optical/IR Surveyor (LUVOIR), will have a similar folding assembly and a primary mirror measuring 8 to 15 meters (26.5 to 49 feet) in diameter – depending on the selected design (LUVOIR-A or -B). As Bhundiya explained to Universe Today via email:

“Today, most spacecraft antennas are deployed in orbit (e.g., Northrop Grumman’s Astromesh antenna) and have been optimized to achieve high performance and gain. However, they have limitations: 1) They are passive deployable systems. I.e. once you deploy them you cannot adaptively change the shape of the antenna. 2) They become difficult to slew as their size increases. 3) They exhibit a tradeoff between diameter and precision. I.e. their precision decreases as their size increases, which is a challenge for achieving astronomy and sensing applications that require both large diameters and high precision (e.g. JWST).”

While many in-space construction methods have been proposed to overcome these limitations, detailed analyses of their performance for building precision structures (like large-diameter reflectors) are lacking. For the sake of their proposal, Cordero and his colleagues conducted a quantitative, system-level comparison of materials and processes for in-space manufacturing. Ultimately, they determined that this limitation could be overcome using advanced materials and a novel in-space manufacturing method called Bend-Forming.

This technique, invented by researchers at the AMSL and described in a recent paper co-authored by Bhundiya and Cordero, relies on a combination of Computer Numerical Control (CNC) deformation processing and hierarchical high-performance materials. As Harsh explained it:

“Bend-Forming is a process for fabricating 3D wireframe structures from metal wire feedstock. It works by bending a single strand of wire at specific nodes and with specific angles, and adding joints to the nodes to make a stiff structure. So to fabricate a given structure, you convert it into bending instructions which can be implemented on a machine like a CNC wire bender to fabricate it from a single strand of feedstock. The key application of Bend-Forming is to manufacture the support structure for a large antenna on orbit. The process is well-suited for this application because it is low-power, can fabricate structures with high compaction ratios, and has essentially no size limit.”

In contrast to other in-space assembly and manufacturing approaches, Bend-Forming is low-power and is uniquely enabled by the extremely low-temperature environment of space. In addition, this technique enables smart structures that leverage multifunctional materials to achieve new combinations of size, mass, stiffness, and precision. Additionally, the resulting smart structures leverage multifunctional materials to achieve unprecedented combinations of size, mass, stiffness, and precision, breaking the design paradigms that limit conventional truss or tension-aligned space structures.

In addition to their native precision, Large Bend-Formed structures can use their electrostatic actuators to contour a reflector surface with sub-millimeter precision. This, said Harsh, will increase the precision of their fabricated antenna in orbit:

“The method of active control is called electrostatic actuation and uses forces generated by electrostatic attraction to precisely shape a metallic mesh into a curved shape which acts as the antenna reflector. We do this by applying a voltage between the mesh and a ‘command surface’ which consists of the Bend-Formed support structure and deployable electrodes. By adjusting this voltage, we can precisely shape the reflector surface and achieve a high-gain, parabolic antenna.”

An arrangement of 3 exoplanets to explore how the atmospheres can look different based on the chemistry present and incoming flux. Credit: Jack H. Madden used with permission

Harsh and his colleagues deduce that this technique will allow for a deployable mirror measuring more than 100 meters (328 ft) in diameter that could achieve a surface precision of 100 m/m and a specific area of more than 10 m2/kg. This capability would surpass existing microwave radiometry technology and could lead to significant improvements in storm forecasts and an improved understanding of atmospheric processes like the hydrologic cycle. This would have significant implications for Earth Observation and exoplanet studies.

The team recently demonstrated a 1-meter (3.3 ft) prototype of an electrostatically-actuated reflector with a Bend-Formed support structure at the 2023 American Institute of Aeronautics and Astronautics (AIAA) SciTech Conference, which ran from January 23rd to 27th in National Harbor, Maryland. With this Phase I NIAC grant, the team plans to mature the technology with the ultimate aim of creating a microwave radiometry reflector.

Looking ahead, the team plans to investigate how Bend-Forming can be used in geostationary orbit (GEO) to create a microwave radiometry reflector with a 15km (9.3 mi) field of view, a ground resolution of 35km (21.75 mi) and a proposed frequency span of 50 to 56 GHz – the super-high and extremely-high frequent range (SHF/EHF). This will enable the telescope to retrieve temperature profiles from exoplanet atmospheres, a key characteristic allowing astrobiologists to measure habitability.

“Our goal with the NIAC now is to work towards implementing our technology of Bend-Forming and electrostatic actuation in space,” said Harsh. “We envision fabricating 100-m diameter antennas in geostationary orbit with have Bend-Formed support structure and electrostatically-actuated reflector surfaces. These antennas will enable a new generation of spacecraft with increased sensing, communication, and power capabilities.”

Further Reading: NASA

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Amateur N.S. astronomer captures magic of the green comet – CBC.ca

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Nova Scotia·Audio

Tim Doucette with the Deep Sky Eye Observatory in southwestern Nova Scotia has captured a dazzling time-lapse of the green comet that’s making a rare pass near Earth.

Comet C/2022 E3 (ZTF) making its closest approach to Earth on Wednesday

Tim Doucette captured a two-hour time-lapse of the green comet over the weekend. (Tim Doucette/Deep Sky Eye Observatory)

An amateur astronomer from southwestern Nova Scotia has captured a dazzling time-lapse of the green comet that’s making a rare pass near Earth.

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The last time the comet was this close to our planet was 50,000 years ago. Many Canadians are looking up at the stars this week as the comet gets ready to make its closest approach on Wednesday.

Tim Doucette with the Deep Sky Eye Observatory near Yarmouth, N.S., is among them.

He took a two-hour time-lapse of the comet during the early-morning hours of Jan. 28.

“If you’ve got a telescope and you look closely at the comet and the background stars, it’s travelling relative in our sky about one-quarter degrees per hour,” he told CBC Radio’s Mainstreet Halifax. “So within a few minutes you can see that the comet’s actually making motion in the night sky.”

You can listen to Doucette’s full interview with host Jeff Douglas here:

Mainstreet NS8:09Astronomer Tim Doucette captures images of rare green comet

A rare green comet that orbits our sun once every 50,000 years is now in our neighbourhood, and already an amateur astronomer has captured dazzling imagery of it.

Amateur N.S. astronomer captures magic of the green comet

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Tim Doucette with the Deep Sky Eye Observatory in southwestern Nova Scotia has captured a dazzling time-lapse of the green comet that’s making a rare pass near Earth.

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With files from CBC Radio’s Mainstreet Halifax

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Kemptville author’s book being sent to the moon

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One of Michael Blouin’s books is going to be launched into space on a microdisk and stay on the surface of the moon. (Submitted by Michael Blouin)

An author from North Grenville, Ont., is going to be part of a small club of authors whose works will be sent to the moon.

Michael Blouin of Kemptville says he’s been interested in space travel since the Apollo 11 mission that landed humans on the moon for the first time.

To be part of a group of hundreds of authors having their work immortalized within the vast expanse of space has him “gobsmacked.”

“I take comfort in the fact that no matter what happens, it looks like my books … will survive and be there,” he said.

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“I sometimes wake up at night and say ‘Oh yeah, I’m going to the moon. Wow.’ It’s kind of amazing.”

How it came to be

Blouin said he’s been a lifelong fan of NASA and space exploration, so when the opportunity to get his work in the Writers on the Moon project came up, he had to take it.

Then around the deadline to apply, his house burned down.

Amid the chaos of not having anywhere to live and then moving into his son’s house, he realized he’d missed his chance.

“I had missed the deadline to apply for this program for books to go to the moon by 12 hours and I was just kicking myself,” he said.

“I lost everything and now I’d missed out on my chance to do something I’d always dreamed about doing.”

Luckily a friend and author in Newfoundland, Carolyn R. Parsons, said she had managed to get some of her work included in the project and had enough space on her microdisk to include him as well.

A rocket sits upright.
This rocket will carry a lander and books from a couple hundred authors up to the moon. (United Launch Alliance)

When do the books go?

The NASA launch is scheduled for Feb. 25 at Cape Canaveral in Florida, which will see his book Skin House brought to the stars along with other works of independent fiction.

Blouin is getting the chance to see the launch.

“These launches sometimes get delayed due to technical reasons or due to weather,” he said.

“But I’m hoping to give myself a big enough window that I’ll actually be on site.”

Blouin had some advice for people who aspire to write or create.

“Any young person aspiring in the arts just shouldn’t give up. Keep trying,” he said. “It can be a tough go but it’s worth every moment.”

He’s getting another of his books — I am Billy the Kid — up to the moon in 2024.

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