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Entertainment

Magic Kingdom TV Universe in the Works at Disney+ (Exclusive)

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‘For All Mankind’ creator Ron Moore is readying the first of a potential franchise of projects that will explore characters from Disney parks and classic films.

Disney is ready to bring the characters from its theme parks and classic films to life in a new way.

The media giant is teaming with For All Mankind creator Ron Moore to develop a franchise for streamer Disney+ that is set in Disney’s beloved Magic Kingdom. The first project in the works as part of the so-called Magic Kingdom Universe is The Society of Explorers and Adventurers, which is set in a world where all the themed lands and characters of the Disney parks and classic films actually exist in another reality.

Noted Disney superfan and For All Mankind creator Ron Moore will write and exec produce SEA for Disney+ and 20th Television. The potential series is currently in the development stage. In success, Moore will build out the Magic Kingdom universe and oversee the entire franchise. More would expand the franchise in a way that’s similar to the world he built out of Syfy’s Battlestar Galactica and, more recently, what Marvel is creating for Disney+.

Reps for Disney+ and 20th Television declined comment.

For the Magic Kingdom Universe, Moore is working closely with the Disney Imagineering team, the group of research and developers who are responsible for the creation and design of all of Disney’s theme parks across the globe. Sources say a mini-writers room is already being put together with a search under way for three senior-level writers.

The idea, per sources, is to explore characters — like sea boat captain from the Jungle Cruise or prospector from Big Thunder Mountain or the climbers of the Matterhorn, for example — as part of the world of The Society of Explorers and Adventurers. (To be clear, none of those characters or storylines are currently on the table at this stage.)

In addition to Disney’s Imagineering team (who were featured in their own docuseries on Disney+), Maril Davis and Ben McGinnis — Moore’s longtime collaborators at his Tall Ship Productions banner — are also attached to SEA and the larger Magic Kingdom Universe.

The potential franchise — which has a seemingly endless number of characters and stories to explore — is the latest collaboration for Moore at Disney since the For All Mankind and Outlander exec producer moved his overall deal from his longtime home at Sony TV to 20th Television. 20th TV’s Carolyn Cassidy spearheaded Moore’s deal with the Disney-backed studio last summer during her tenure as president of the Fox-turned-Disney studio. (As part of Disney’s December reorganization, Cassidy now serves as exec vp development under new president and former ABC topper Karey Burke.)

Under the multiyear agreement, which sources estimated is worth in the eight-figure range all in, Moore and his Tall Ship Productions banner will create and develop new projects across the Disney portfolio. His first project under the pact is the Disney+ series Swiss Family Robinson, which he’s working on alongside Jon M. Chu (Crazy Rich Asians).

Moore received multiple lucrative offers from other streamers and studios but opted to leave money on the table to sign with 20th TV. Sony TV, sources say, was among those who pursued a new deal with Moore. The independent studio, for whom Moore has delivered both Starz’s Outlander and Apple’s For All Mankind, offered a more lucrative deal but Moore ultimately opted to sign with 20th TV and pursue a his longtime passion for Disney. (Moore also was instrumental in bringing Diana Gabaldon’s beloved Outlander novels to television, with producers Sony TV currently readying a spinoff.)

“I decided to go there mostly because my childhood was built around a lot of things that were Disney. I am a huge fan and aficionado of the Disneyland park in Anaheim to the point where I would go there by myself periodically and ride the rides,” Moore told The Hollywood Reporter podcast TV’s Top 5 in an interview this month. “The opportunity for me to get to work on a lot of the classic IP that Disney has and things in their library that meant so much to me as a child growing up and that I have shared with my children ultimately was just something I couldn’t pass up.” Moore, who previously flirted with a Star Wars live-action TV series with George Lucas for Disney-owned ABC nearly a decade ago, also noted he’s eager to revisit the franchise as part of his lucrative new Disney pact.

The Magic Kingdom Universe would mark a massive brand integration for Disney+. The year-old streamer has already unveiled extensive plans to build-out the worlds of Star Wars and Marvel with nearly a dozen live-action scripted series in the works for both franchises. Star Wars offshoot The Mandalorian and Marvel’s first Disney+ series WandaVision have become critical and commercial breakouts for the platform. The Magic Kingdom Universe would further expand the worlds of Disney’s beloved theme parks and naturally compliment the roster of Disney feature films that stream exclusively on Disney+.

Moore is repped by CAA.



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Science

Gravity May Play a Tiny But Important Role in The Microworld of Particle Physics

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Launch yourself from a great enough height and it won’t take long to see which would win in a battle between gravity and the forces that bind solid ground.

Gravity’s relative weakness, at least compared to the strength of electromagnetism and the nuclear forces, appears to limits its power to phenomena on the vast scales of planets and galaxies.

 

For this reason, together with the challenge of marrying general relativity with quantum physics, physicists tend to hand-wave gravity’s role in the formation of particles by fudging it with a rather arbitrary correction factor.

Two physicists from the Institute of Gravitation and Cosmology at the Peoples’ Friendship University of Russia (RUDN University) are now rethinking gravity’s place among the building blocks of nature, searching for solutions to equations that would give this small force a bigger role in explaining how fundamental particles could emerge.

At first glance, it seems like an unnecessary search. For a typical elementary particle, like an electron, its electromagnetic pull is 10^40 times stronger than its gravitational might.

Including gravity’s effects when describing an electron’s movements around an atom’s nucleus would be like taking a mosquito’s impact into account when discussing a car crash.

Researchers Ahmed Alharthy and Vladimir V. Kassandrov think the mosquito might be more important than we give it credit for, at least on the mind-blowingly small level of the Planck scale.

“Gravity can potentially play an important role in the microworld, and this assumption is confirmed by certain data,” says Kassandrov.

 

Established solutions to fundamental field theory equations in curving spacetime appear to leave room for a small but non-zero influence of gravity when we zoom in close. As distances shrink, gravity’s tug eventually becomes comparable with that of attracted charges.

There are also models describing solitary waves forming in quantum fields in which the tiny effect of gravity could well help reinforce the wave.

The duo went back to semi-classical models of electromagnetic field equations, swapping out the hand-waved correction typically used and applying rules that allow them to tweak some quantities while ensuring others remain fixed.

By slotting in quantities defining the charge and mass of known elementary particles, the team went on the hunt for solutions that added up.

For the most part, there were no clear situations where gravity seemed necessary, at least for known particles.

But there were scenarios as distances shrank to around 10^-33 metres for charged objects with a mass of 10^-5 grams where solutions appeared.

The theorists aren’t sure if their answers describe anything we might find in the Universe, though they do set some limits on a spectrum that corresponds with hypothetical semi-quantum particles called maximons.

 

Pushing the mathematics further, as electric charge vanishes into nothingness on the smallest of scales, and masses grow to a stellar-magnitude, it’s clear that gravity becomes a key factor in the emergence of some objects from the quantum landscape.

That might sound like a flight of fancy, but such neutral matter-waves are the very things that make up hypothetical objects known as boson stars.

For now, gravity will continue to be reduced to a begrudging side-note in particle physics, its tiny force a mathematical complexity providing no appreciable benefit in its solving.

One day, we just might need to give the weakest of the four fundamental forces its due on the Universe’s smallest scales.

“In the future, we would like to shed light on this problem that is intriguing for physicists but extremely complex from the point of view of mathematics,” says Kassandrov.

This research was published in Universe.

 

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Technology

Bungie Is Looking To Expand The Destiny 2 Universe

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Image: Bungie

Yesterday, Bungie announced some big plans over the next few years, including new offices, new games, and a new leadership team seemingly in charge of branching out the the Destiny 2 universe into other media.

“[O]ne of the primary drivers of Bungie’s expansion is to increase the commitment to the long-term development of Destiny 2, tell new stories in the Destiny Universe, and create entirely new worlds in to-be-announced IPs,” the studio wrote over on its website.

In material terms the expansion includes a big new HQ office that sounds effectively like a mini-college campus, an international office in Amsterdam focused on publishing and marketing, and new people brought on board at the executive and board of directors level, including the appointment of former Viacom CBS president of consumer products, Pamela Kaufman. In aspirational terms, Bungie wants to expand the “Destiny Universe into additional media,” and release a brand new game before 2025. Bungie had previously announced it was working on a new non-Destiny game as part of a $100 million publishing deal with Chinese gaming company NetEase.

Previously synonymous with Halo, Bungie has spent the greater part of the last decade becoming the Destiny company. It seems the independent studio is looking to double-down on that trend while also still developing new projects. Last year, Destiny 2 director Luke Smith announced a multi-year plan to continue the game’s annual expansions rather than working on a Destiny 3, a move that came after the studio finally cut ties with publisher Activision.

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All of this seems very much in keeping with the decade-long vision originally laid out for the first Destiny, which at the time then-Bungie COO (and now CEO) Pete Parsons said was part of trying to turn the IP into gaming’s version of Star Wars and Lord of the Rings. Destiny’s always been a very cinematic game, with voice talents that have ranged from Peter Dinklage and Gina Torres to Nathan Fillion and Lance Reddick. It seems like the perfect time for the world it’s established to be brought into TV or film, especially as Hollywood races to adapt every video game to fill its bottomless appetite for new content.

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Science

A New Measurement of Quantum Space-Time Has Found Nothing Going On

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In the very smallest measured units of space and time in the Universe, not a lot is going on. In a new search for quantum fluctuations of space-time on Planck scales, physicists have found that everything is smooth.

 

This means that – for now at least – we still can’t find a way to resolve general relativity with quantum mechanics.

It’s one of the most vexing problems in our understanding of the Universe.

General relativity is the theory of gravitation that describes gravitational interactions in the large-scale physical Universe. It can be used to make predictions about the Universe; general relativity predicted gravitational waves, for instance, and some behaviours of black holes.

Space-time under relativity follows what we call the principle of locality – that is, objects are only directly influenced by their immediate surroundings in space and time.

In the quantum realm – atomic and subatomic scales – general relativity breaks down, and quantum mechanics takes over. Nothing in the quantum realm happens at a specific place or time until it is measured, and parts of a quantum system separated by space or time can still interact with each other, a phenomenon known as nonlocality.

Somehow, in spite of their differences, general relativity and quantum mechanics exist and interact. But so far, resolving the differences between the two has proven extremely difficult.

 

This is where the Holometer at Fermilab comes into play – a project headed by astronomer and physicist Craig Hogan from the University of Chicago. This is an instrument designed to detect quantum fluctuations of space-time at the smallest possible units – a Planck length, 10-33 centimetres, and Planck time, how long it takes light to travel a Planck length.

It consists of two identical 40-metre (131-foot) interferometers that intersect at a beam splitter. A laser is fired at the splitter and sent down two arms to two mirrors, to be reflected back to the beam splitter to recombine. Any Planck-scale fluctuations will mean the beam that returns is different from the beam that was emitted.

A few years ago, the Holometer made a null detection of back-and-forth quantum jitters in space-time. This suggested that space-time itself as we can currently measure it is not quantised; that is, could be broken down into discrete, indivisible units, or quanta.

Because the interferometer arms were straight, it could not detect other kinds of fluctuating motion, such as if the fluctuations were rotational. And this could matter a great deal.

 

“In general relativity, rotating matter drags space-time along with it. In the presence of a rotating mass, the local nonrotating frame, as measured by a gyroscope, rotates relative to the distant Universe, as measured by distant stars,” Hogan wrote on the Fermilab website.

“It could well be that quantum space-time has a Planck-scale uncertainty of the local frame, which would lead to random rotational fluctuations or twists that we would not have detected in our first experiment, and much too small to detect in any normal gyroscope.”

So, the team redesigned the instrument. They added additional mirrors so that they would be able to detect any rotational quantum motion. The result was an incredibly sensitive gyroscope that can detect Planck-scale rotational twists that change direction a million times per second.

In five observing runs between April 2017 and August 2019, the team collected 1,098 hours of dual interferometer time series data. In all that time, there was not a single jiggle. As far as we know, space-time is still a continuum.

But that doesn’t mean the Holometer, as has been suggested by some scientists, is a waste of time. There’s no other instrument like it in the world. The results it returns – null or not – will shape future efforts to probe the intersection of relativity and quantum mechanics at Planck scales.

“We may never understand how quantum space-time works without some measurement to guide theory,”  Hogan said. “The Holometer program is exploratory. Our experiment started with only rough theories to guide its design, and we still do not have a unique way to interpret our null results, since there is no rigorous theory of what we are looking for.

“Are the jitters just a bit smaller than we thought they might be, or do they have a symmetry that creates a pattern in space that we haven’t measured? New technology will enable future experiments better than ours and possibly give us some clues to how space and time emerge from a deeper quantum system.”

The research has been published on arXiv.

 

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Science

Earliest Supermassive Black Hole and Quasar in the Universe Discovered

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Quasars are the most energetic objects in the universe, which is why astronomers can observe them from so far away. Credit: NOIRLab/NSF/AURA/J. da Silva

Nearly every galaxy hosts a monster at its center — a supermassive black hole millions to billions times the size of the Sun. While there’s still much to learn about these objects, many scientists believe they are crucial to the formation and structure of galaxies. What’s more, some of these black holes are particularly active, whipping up stars, dust and gas into glowing accretion disks emitting powerful radiation into the cosmos as they consume matter around them. These quasars are some of the most distant objects that astronomers can see, and there is now a new record for the farthest one ever observed.

A team of scientists, led by former UC Santa Barbara postdoctoral scholar Feige Wang and including Professor Joe Hennawi and current postdoc Riccardo Nanni, announced the discovery of J0313-1806, the most distant quasar discovered to date. Seen as it would have appeared more than 13 billion years ago, this fully formed distant quasar is also the earliest yet discovered, providing astronomers insight into the formation of massive galaxies in the early universe. The team’s findings were released at the January 2021 meeting of the American Astronomical Society and published in Astrophysical Journal Letters.

The quasar appears as little more than a spot in the researchers’ data. Credit: Feige Wang et al.

Quasars are the most energetic objects in the universe. They occur when gas in the superheated accretion disk around a supermassive black hole is inexorably drawn inwards, shedding energy across the electromagnetic spectrum. This releases enormous amounts of electromagnetic radiation, with the most massive examples easily outshining entire galaxies.

Quasar J0313-1806 lies 13 billion light years away, and existed a mere 690 million years after the Big Bang. It is powered by the earliest known supermassive black hole, which, despite its early formation, still weighs in at more than 1.6 billion times the mass of the Sun. Indeed, J0313-1806 outshines the modern Milky Way by a factor of 1,000.

Photo of Riccardo Nanni. Credit: UC Santa Barbara

“The most distant quasars are crucial for understanding how the earliest black holes formed and for understanding cosmic reionization — the last major phase transition of our universe,” said co-author Xiaohui Fan, a professor of astronomy at the University of Arizona.

The presence of such a massive black hole so early in the universe’s history challenges theories of black hole formation. As lead author Wang, now a NASA Hubble fellow at the University of Arizona, explains: “Black holes created by the very first massive stars could not have grown this large in only a few hundred million years.”

The team first detected J0313-1806 after combing through data from large area digital sky surveys. Crucial to the characterization of the new quasar was a high-quality spectrum obtained at the W. M. Keck Observatory: “Through University of California Observatories, we have privileged access to the Keck telescopes on the summit of Mauna Kea, which allowed us to obtain high quality data on this object shortly after it was confirmed to be a quasar at other telescopes,” Hennawi said.

As well as weighing the monster black hole, the Keck Observatory observations uncovered an exceptionally fast outflow emanating from the quasar in the form of a high-velocity wind traveling at 20% of the speed of light. “The energy released by such an extreme high-velocity outflow is large enough to impact the star formation in the entire quasar host galaxy,” said Jinyi Yang, of Steward Observatory at the University of Arizona.

Joseph Hennawi. Credit: UC Santa Barbara

The early galaxy hosting the quasar is undergoing a surge of star formation, producing new stars 200 times faster than the modern-day Milky Way. The system is the earliest known example of a quasar sculpting the growth of its host galaxy. The combination of this intense star formation, the luminous quasar and the high-velocity outflow make J0313-1806 and its host galaxy a promising natural laboratory for understanding the growth of supermassive black holes and their host galaxies in the early universe.

“This would be a great target to investigate the formation of the earliest supermassive black holes,” concluded Wang. “We also hope to learn more about the effect of quasar outflows on their host galaxy — as well as to learn how the most massive galaxies formed in the early universe.”

Finding these distant quasars requires incredibly painstaking work, since they are like needles in a haystack. Astronomers mine digital images of billions of celestial objects in order to find promising quasar candidates. “The current success rate for finding these objects is around 1%. You have to kiss a lot frogs before finding your prince,” remarked Hennawi.

Hennawi, Wang and Nanni are developing machine learning tools to analyze this big data and make the process of finding distant quasars more efficient. “In the coming years the European Space Agency’s Euclid satellite and NASA’s James Webb Space Telescope will enable us to find perhaps a hundred quasars at this distance, or farther,” Hennawi said. “With a large statistical sample of these objects we will be able to construct a precise timeline of the reionization epoch as well as shed more light on how these massive black holes formed.”

For more information on this study:

Reference: “A Luminous Quasar at Redshift 7.642” by Feige Wang, Jinyi Yang, Xiaohui Fan, Joseph F. Hennawi, Aaron J. Barth, Eduardo Banados, Fuyan Bian, Konstantina Boutsia, Thomas Connor, Frederick B. Davies, Roberto Decarli, Anna-Christina Eilers, Emanuele Paolo Farina, Richard Green, Linhua Jiang, Jiang-Tao Li, Chiara Mazzucchelli, Riccardo Nanni, Jan-Torge Schindler, Bram Venemans, Fabian Walter, Xue-Bing Wu and Minghao Yue, 14 January 2021, Astrophyiscal Journal Letters.
DOI: 10.3847/2041-8213/abd8c6



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Science

NASA chooses Elon Musk’s SpaceX for nearly $100M mission to map the beginning of our universe

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NASA is teaming up with Elon Musk’s SpaceX on a two-year astrophysics mission to help better understand the birth of the universe and the development of galaxies. 

NASA on Thursday revealed it has awarded a contract to SpaceX for the launch of SPHEREx, which stands for Spectro-Photometer for the History of the Universe, Epoch of Reionization, and Ices Explorer. 

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The spacecraft is due to launch via a SpaceX Falcon 9 rocket in June 2024 from Space Launch Complex-4E at Vandenberg Air Force Base in California. The total cost to launch SPHEREx is about $98.8 million. 

NASA says the spacecraft will survey the sky in near-infrared light, which is not visible to the human eye, as a tool to help answer questions about the origins of the universe and how galaxies form. 

“It also will search for water and organic molecules – essentials for life as we know it – in regions where stars are born from gas and dust, known as stellar nurseries, as well as disks around stars where new planets could be forming,” NASA said in a news release. 

The mission will gather data from more than 300 million galaxies and more than 100 million stars in the Milky Way galaxy.  

The contract is the latest NASA has awarded SpaceX over the past several years. SpaceX last year launched astronauts to space for the first time. It was the first privately designed and built spacecraft to launch astronauts to space and the first time NASA had launched its own astronauts since the end of the space shuttle program in 2011. 

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There Is One Way Humans Could ‘Safely’ Enter a Black Hole, Physicists Say

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To solve the mysteries of black holes, a human should just venture into one.

However, there is a rather complicated catch: A human can do this only if the respective black hole is supermassive and isolated, and if the person entering the black hole does not expect to report the findings to anyone in the entire Universe.

 

We are both physicists who study black holes, albeit from a very safe distance. Black holes are among the most abundant astrophysical objects in our Universe.

These intriguing objects appear to be an essential ingredient in the evolution of the Universe, from the Big Bang till present day. They probably had an impact on the formation of human life in our own galaxy.

A person falling into a black hole and being stretched. (Leo Rodriguez/Shanshan Rodriguez/CC BY-ND)

Two types of black holes

The Universe is littered with a vast zoo of different types of black holes.

They can vary by size and be electrically charged, the same way electrons or protons are in atoms. Some black holes actually spin. There are two types of black holes that are relevant to our discussion.

The first does not rotate, is electrically neutral – that is, not positively or negatively charged – and has the mass of our Sun. The second type is a supermassive black hole, with a mass of millions to even billions times greater than that of our Sun.

Besides the mass difference between these two types of black holes, what also differentiates them is the distance from their center to their “event horizon” – a measure called radial distance.

A person falling into a supermassive black hole would likely survive. (Leo & Shanshan Rodriguez/CC BY-ND)

The event horizon of a black hole is the point of no return. Anything that passes this point will be swallowed by the black hole and forever vanish from our known Universe.

At the event horizon, the black hole’s gravity is so powerful that no amount of mechanical force can overcome or counteract it. Even light, the fastest-moving thing in our Universe, cannot escape – hence the term “black hole”.

The radial size of the event horizon depends on the mass of the respective black hole and is key for a person to survive falling into one. For a black hole with a mass of our Sun (one solar mass), the event horizon will have a radius of just under 2 miles (3.2 kilometres).

A person approaching the event horizon of a a Sun-size black hole. (Leo and Shanshan Rodriguez/CC BY-ND)

The supermassive black hole at the center of our Milky Way galaxy, by contrast, has a mass of roughly 4 million solar masses, and it has an event horizon with a radius of 7.3 million miles or 17 solar radii.

Thus, someone falling into a stellar-size black hole will get much, much closer to the black hole’s center before passing the event horizon, as opposed to falling into a supermassive black hole.

 

This implies, due to the closeness of the black hole’s center, that the black hole’s pull on a person will differ by a factor of 1,000 billion times between head and toe, depending on which is leading the free fall.

In other words, if the person is falling feet first, as they approach the event horizon of a stellar mass black hole, the gravitational pull on their feet will be exponentially larger compared to the black hole’s tug on their head.

The person would experience spaghettification, and most likely not survive being stretched into a long, thin noodle-like shape.

Now, a person falling into a supermassive black hole would reach the event horizon much farther from the the central source of gravitational pull, which means that the difference in gravitational pull between head and toe is nearly zero.

Thus, the person would pass through the event horizon unaffected, not be stretched into a long, thin noodle, survive and float painlessly past the black hole’s horizon.

Other considerations

Most black holes that we observe in the Universe are surrounded by very hot disks of material, mostly comprising gas and dust or other objects like stars and planets that got too close to the horizon and fell into the black hole.

These disks are called accretion disks and are very hot and turbulent. They are most certainly not hospitable and would make traveling into the black hole extremely dangerous.

 

To enter one safely, you would need to find a supermassive black hole that is completely isolated and not feeding on surrounding material, gas, or even stars.

Now, if a person found an isolated supermassive black hole suitable for scientific study and decided to venture in, everything observed or measured of the black hole interior would be confined within the black hole’s event horizon.

Keeping in mind that nothing can escape the gravitational pull beyond the event horizon, the in-falling person would not be able to send any information about their findings back out beyond this horizon. Their journey and findings would be lost to the rest of the entire Universe for all time. But they would enjoy the adventure, for as long as they survived … maybe ….

Leo Rodriguez, Assistant Professor of Physics, Grinnell College and Shanshan Rodriguez, Assistant Professor of Physics, Grinnell College.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

 

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Astronomers spot bizarre, never-before-seen activity from one of the strongest magnets in the universe

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Artist’s impression of the active magnetar Swift J1818.0-1607. Credit: Carl Knox, OzGrav.

Astronomers from the ARC Centre of Excellence for Gravitational Wave Discovery (OzGrav) and CSIRO have just observed bizarre, never-seen-before behavior from a radio-loud magnetar—a rare type of neutron star and one of the strongest magnets in the universe.

Their new findings, published today in the Monthly Notices of the Royal Astronomical Society (MNRAS), suggest magnetars have more complex magnetic fields than previously thought, which may challenge theories of how they are born and evolve over time.

Magnetars are a rare type of rotating neutron star with some of the most powerful magnetic fields in the universe. Astronomers have detected only 30 of these objects in and around the Milky Way—most of them detected by X-ray telescopes following a high-energy outburst.

However, a handful of these magnetars have also been seen to emit radio pulses similar to pulsars—the less-magnetic cousins of magnetars that produce beams of radio waves from their magnetic poles. Tracking how the pulses from these radio-loud magnetars change over time offers a unique window into their evolution and geometry.

In March 2020, a new magnetar named Swift J1818.0-1607 (J1818 for short) was discovered after it emitted a bright X-ray burst. Rapid follow-up observations detected radio pulses originating from the magnetar. Curiously, the appearance of the radio pulses from J1818 were quite different from those detected from other radio-loud magnetars.

Most radio pulses from magnetars maintain a consistent brightness across a wide range of observing frequencies. However, the pulses from J1818 were much brighter at low frequencies than high frequencies—similar to what is seen in pulsars, another more common type of radio-emitting neutron star.

In order to better understand how J1818 would evolve over time, a team led by scientists from the ARC Centre of Excellence for Gravitational Wave Discovery (OzGrav) observed it eight times using the CSIRO Parkes radio telescope (also known as Murriyang) between May and October 2020.

During this time, they found the magnetar underwent a brief identity crisis: In May it was still emitting the unusual pulsar-like pulses that had been detected previously; however, by June, it had started flickering between a bright and a weak state. This flickering behavior reached a peak in July, when the astronomers saw it flickering back and forth between pulsar-like and magnetar-like radio pulses.

“This bizarre behavior has never been seen before in any other radio-loud magnetar,” explains study lead author and Swinburne University/CSIRO Ph.D. student Marcus Lower. “It appears to have only been a short-lived phenomenon, as by our next observation, it had settled permanently into this new magnetar-like state.”

The scientists also looked for pulse shape and brightness changes at different radio frequencies and compared their observations to a 50-year-old theoretical model. This model predicts the expected geometry of a pulsar, based on the twisting direction of its polarized light.

“From our observations, we found that the magnetic axis of J1818 isn’t aligned with its rotation axis,” says Lower. “Instead, the radio-emitting magnetic pole appears to be in its southern hemisphere, located just below the equator. Most other magnetars have magnetic fields that are aligned with their spin axes or are a little ambiguous. This is the first time we have definitively seen a magnetar with a misaligned magnetic pole.”

Remarkably, this magnetic geometry appears to be stable over most observations. This suggests any changes in the pulse profile are simply due to variations in the height the radio pulses are emitted above the neutron star surface. However, the August 1st 2020 observation stands out as a curious exception.

“Our best geometric model for this date suggests that the radio beam briefly flipped over to a completely different magnetic pole located in the northern hemisphere of the magnetar,” says Lower.

A distinct lack of any changes in the magnetar’s pulse profile shape indicate the same magnetic field lines that trigger the ‘normal’ radio pulses must also be responsible for the pulses seen from the other magnetic pole.

The study suggests this is evidence that the radio pulses from J1818 originate from loops of magnetic field lines connecting two closely spaced poles, like those seen connecting the two poles of a horseshoe magnet or sunspots on the sun. This is unlike most ordinary neutron stars, which are expected to have north and south poles on opposite sides of the star that are connected by a donut-shaped magnetic field.

This peculiar magnetic field configuration is also supported by an independent study of the X-rays pulses from J1818 that were detected by the NICER telescope on board the International Space Station. The X-rays appear to come from either a single distorted region of magnetic field lines that emerge from the magnetar surface or two smaller, but closely spaced, regions.

These discoveries have potential implications for computer simulations of how magnetars are born and evolve over long periods of time, as more complex magnetic field geometries will change how quickly their magnetic fields are expected to decay over time. Additionally, theories that suggest fast radio bursts can originate from magnetars will have to account for radio pulses potentially originating from multiple active sites within their magnetic fields.

Catching a flip between magnetic poles in action could also afford the first opportunity to map the magnetic field of a magnetar.

“The Parkes telescope will be watching the magnetar closely over the next year” says scientist and study co-author Simon Johnston, from the CSIRO Astronomy and Space Science.

Mysterious spinning neutron star detected in the Milky Way proves to be an extremely rare discovery

More information:
M E Lower et al. The dynamic magnetosphere of Swift J1818.0−1607, Monthly Notices of the Royal Astronomical Society (2020). DOI: 10.1093/mnras/staa3789

Marcus E. Lower, et al. The dynamic magnetosphere of Swift J1818.0−1607 arxiv.org/abs/2011.12463 arXiv:2011.12463v2 [astro-ph.HE] T

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In a World First, Physicists Narrow Down The Possible Mass of Dark Matter

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We may not know what dark matter is, but scientists now have a better idea of what to look for.

Based on quantum gravity, physicists have worked out new, much more stringent upper and lower mass limits of dark matter particles. And they have found that the mass range is way tighter than previously thought.

 

This means that the dark matter candidates that are either extremely light or heavy are unlikely to be the answer, based on our current understanding of the Universe.

“This is the first time that anyone has thought to use what we know about quantum gravity as a way to calculate the mass range for dark matter. We were surprised when we realised no-one had done it before – as were the fellow scientists reviewing our paper,” said physicist and astronomer Xavier Calmet of the University of Sussex in the UK.

“What we’ve done shows that dark matter cannot be either ‘ultra-light’ or ‘super-heavy’ as some theorise – unless there is an as-yet unknown additional force acting on it. This piece of research helps physicists in two ways: it focuses the search area for dark matter, and it will potentially also help reveal whether or not there is a mysterious unknown additional force in the Universe.”

Dark matter is undeniably one of the biggest mysteries of the Universe as we know it. It’s the name we give to a mysterious mass responsible for gravitational effects that can’t be explained by the stuff we can detect by other means – the normal matter such as stars, dust, and galaxies.

 

For example, galaxies rotate much faster than they should if they were just being gravitationally influenced by the normal matter in them; gravitational lensing – the bending of spacetime around massive objects – is far stronger than it should be. Whatever is creating this additional gravity is beyond our ability to detect directly.

We know it only by the gravitational effect it has on other objects. Based on this effect, we know there is a lot of it out there. Roughly 80 percent of all matter in the Universe is dark matter. It’s called dark matter because, well, it’s dark. And also mysterious.

However, we do know that dark matter interacts with gravity, so Calmet and his colleague, physicist and astronomer Folkert Kuipers of the University of Sussex, turned to the qualities of quantum gravity to try and estimate the mass range of a hypothetical dark matter particle (whatever it may be).

Quantum gravity, they explain, places a number of bounds on whether dark matter particles of various masses can exist. While we don’t have a decent working theory that unites general relativity’s space-bending description of gravity with the discrete chunkiness of quantum physics, we know any melding of the two would reflect certain fundamentals of both. As such, dark matter particles would have to obey quantum gravitational rules on how particles break down or interact.

 

By carefully accounting for all these bounds, they were able to rule out mass ranges unlikely to exist under our current understanding of physics.

Based on the assumption that only gravity can interact with dark matter, they determined that the mass of the particle should fall between 10-3 electronvolts and 107 electronvolts, depending on the spins of the particles, and the nature of dark matter interactions.

That’s insanely smaller than the 10-24 electronvolt to 1019 gigaelectronvolt range traditionally ascribed, the researchers said. And that’s important, because it largely excludes some candidates, such as WIMPs (weakly interacting massive particles).

If such candidates do later turn out to be the culprit behind the dark matter mystery, according to Calmet and Kuipers, it would mean they are being influenced by some force we don’t yet know about.

That would be really cool, because it would point to new physics – a new tool for analysing and understanding our Universe.

Above all, the team’s constraints provide a new frame to consider in the search for dark matter, helping narrow down where and how to look.

“As a PhD student, it’s great to be able to work on research as exciting and impactful as this,” Kuipers said. “Our findings are very good news for experimentalists as it will help them to get closer to discovering the true nature of dark matter.”

The research has been published in Physics Letters B.

 

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Black Holes Could Get So Humongous, Astronomers Came Up With a New Size Category

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There are supermassive black holes. There are ultramassive black holes. How large can these strange objects grow? Well, there could be something even bigger than ultramassive: stupendously large black holes, according to the latest research.

 

Such hypothetical black holes – larger than 100 billion times the mass of the Sun – have been explored in a new paper which names them SLABs, an acronym that stands for “Stupendously LArge Black holeS”.

“We already know that black holes exist over a vast range of masses, with a supermassive black hole of 4 million solar masses residing at the centre of our own galaxy,” explained astronomer Bernard Carr of Queen Mary University London.

“Whilst there isn’t currently evidence for the existence of SLABs, it’s conceivable that they could exist and they might also reside outside galaxies in intergalactic space, with interesting observational consequences.”

Black holes have only a few somewhat broad mass categories. There are stellar-mass black holes; those are black holes that are around the mass of a star, up to around 100 solar masses. The next category up is intermediate mass black holes, and how large they get seems to depend on who you talk to. Some say 1,000 solar masses, some say 100,000, and others say 1 million; whatever the upper limit is, these seem to be pretty rare.

 

Supermassive black holes (SMBHs) are much, much larger, on the order of millions to billions of solar masses. These include the SMBH at the heart of the Milky Way, Sagittarius A*, at 4 million solar masses, and the most photogenic SMBH in the Universe, M87*, at 6.5 billion solar masses.

The chonkiest black holes we’ve detected are ultramassive, more than 10 billion (but less than 100 billion) solar masses. These include an absolute beast clocking in at 40 billion solar masses in the centre of a galaxy named Holmberg 15A.

“However, surprisingly, the idea of SLABs has largely been neglected until now,” Carr said.

“We’ve proposed options for how these SLABs might form, and hope that our work will begin to motivate discussions amongst the community.”

The thing is, scientists don’t quite know how really big black holes form and grow. One possibility is that they form in their host galaxy, then grow bigger and bigger by slurping up a whole lot of stars and gas and dust, and collisions with other black holes when galaxies merge.

This model has an upper limit of around 50 billion solar masses – that’s the limit at which the object’s prodigious mass would require an accretion disc so massive it would fragment under its own gravity. But there’s also a significant problem: Supermassive black holes have been found in the early Universe at masses too high to have grown by this relatively slow process in the time since the Big Bang.

 

Another possibility is something called primordial black holes, first proposed in 1966. The theory goes that the varying density of the early Universe could have produced pockets so dense, they collapsed into black holes. These would not be subject to the size constraints of black holes from collapsed stars, and could be extremely small or, well, stupendously large.

The extremely small ones, if they ever existed, would probably have evaporated due to Hawking radiation by now. But the much, much larger ones could have survived.

So, based on the primordial black hole model, the team calculated exactly how stupendously large these black holes could be, between 100 billion and 1 quintillion (that’s 18 zeroes) solar masses.

The purpose of the paper, the researchers said, was to consider the effect of such black holes on the space around them. We may not be able to see SLABs directly – black holes that aren’t accreting material are invisible, since light cannot escape their gravity – but massive invisible objects can still be detected based on the way space around them behaves.

Gravity, for instance, curves space-time, which causes the light travelling through those regions to also follow a curved path; this is called a gravitational lens, and the effect could be used to detect SLABs in intergalactic space, the team said.

The huge objects also would have implications for the detection of dark matter, the invisible mass that’s injecting way more gravity into the Universe than there should be – based on what we can actually directly detect.

One hypothetical dark matter candidate, weakly interacting massive particles (WIMPs), would accumulate in the region around a SLAB due to the immense gravity, in such concentrations that they would collide with and annihilate each other, creating a gamma-radiation halo.

And primordial black holes are themselves a dark matter candidate, too.

“SLABs themselves could not provide the dark matter,” Carr said. “But if they exist at all, it would have important implications for the early Universe and would make it plausible that lighter primordial black holes might do so.”

Also, we couldn’t resist calculating the size of a 1 quintillion solar mass black hole. The event horizon would end up over 620,000 light-years across. Uh. Stupendous.

The team’s research has been published in the Monthly Notices of the Royal Astronomical Society.

 

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