From PI: Women in STEM-“Celebrating International Women’s Day”

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Is it not a shame that we need to have a special day to celebrate women when they are so already fantastic and exceptionally brilliant in the physical sciences?

Check out this blog post-
https://sciencesprings.wordpress.com/2018/03/08/from-the-conversation-women-in-stem-perish-not-publish-new-study-quantifies-the-lack-of-female-authors-in-scientific-journals/

“”I have done a couple of STEM events, but there have never been this many girls. There are so many here. It is really empowering. Go girls in STEM!” Eama, Grade 12

Today’s Inspiring Future Women in Science conference was a success. Mona Nemar, Canada’s Chief Science Advisor, gave opening remarks encouraging the students in attendance to take advantage of the opportunity to learn from the speakers to come.

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“The days of women being held back or being excluded from science are over. Now, more than ever women are entering, remaining in, and revolutionizing the science fields. Today is a shining example of that.”
-Mona Nemar, Chief Science Advisor, Government of Canada

Mona, read my above post on women getting not published.

The speakers and panelists, who included a chemist, engineer, astronomer, ecologist, and surgeon, talked about the challenges and triumphs that a career in STEM brings. Students were then treated to a speed mentoring session where they were able to ask questions and interact with women from a broad number of STEM careers. Read more about how this conference is inspiring young women here.

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“This conference showed me there are so many things you can do going into [a career in STEM], so now I feel more inspired, and I feel more confident and not scared to go into science.” Lealan, Age 16

Programs like Perimeter’s “Inspiring Future Women in Science” conference are helping young women see their own potential and reach out for careers in STEM. And more talented female scientists today, means a brighter future tomorrow.

Thank you for being part of the equation.
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#accelerator-science, #applied-research-technology, #astronomy, #astrophysics, #basic-research, #biology, #cancer, #chemistry, #clean-energy, #cosmology, #dark-matter-and-dark-energy, #international-womens-day, #material-sciences-2, #medicine, #particle-physics, #perimeter-institute, #physics, #radio-astronomy

From PI: “Recent Perimeter News”

Perimeter Institute

Perimeter Institute

A Stellar Year

From the dawn of multi-messenger astronomy to the discovery of more Earth-sized exoplanets and a solar eclipse that captivated millions, 2017 was a year in which humanity turned its gaze skyward.

Many believe we have entered a new “golden age” of physics. Researchers at Perimeter continue to probe for answers about dark matter, quantum gravity, black holes, and the birth of the universe.

The Centre for the Universe

In November 2017, Perimeter announced the creation of the Centre for the Universe – a new hub for cutting-edge cosmology research. Centre patrons include world-renowned cosmologist Stephen Hawking and Nobel Prize winner Art MacDonald. The Centre will bring together international scientists, bridging fundamental theory and experiment, to tackle questions about the origin, evolution, and fate of the universe.

Read more here.

On the Horizon

The Event Horizon Telescope (EHT) project turned its incredibly precise gaze toward a black hole earlier this year, and the scientific world awaits the resulting imagery.

Event Horizon Telescope Array

Arizona Radio Observatory
Arizona Radio Observatory/Submillimeter-wave Astronomy (ARO/SMT)

ESO/APEX
Atacama Pathfinder EXperiment

CARMA Array no longer in service
Combined Array for Research in Millimeter-wave Astronomy (CARMA)

Atacama Submillimeter Telescope Experiment (ASTE)
Atacama Submillimeter Telescope Experiment (ASTE)

Caltech Submillimeter Observatory
Caltech Submillimeter Observatory (CSO)

IRAM NOEMA interferometer
Institut de Radioastronomie Millimetrique (IRAM) 30m

James Clerk Maxwell Telescope interior, Mauna Kea, Hawaii, USA
James Clerk Maxwell Telescope interior, Mauna Kea, Hawaii, USA

Large Millimeter Telescope Alfonso Serrano
Large Millimeter Telescope Alfonso Serrano

CfA Submillimeter Array Hawaii SAO
Submillimeter Array Hawaii SAO

ESO/NRAO/NAOJ ALMA Array
ESO/NRAO/NAOJ ALMA Array, Chile

South Pole Telescope SPTPOL
South Pole Telescope SPTPOL

Future Array/Telescopes

Plateau de Bure interferometer
Plateau de Bure interferometer

NSF CfA Greenland telescope

Greenland Telescope

A process called Very Long Baseline Interferometry (VLBI) is used by this network of eight large radio telescopes to capture history’s first picture of a black hole’s event horizon. Avery Broderick leads Perimeter’s Event Horizon Initiative, which will help analyze and interpret the data collected by the telescope array. The EHT team is waiting for the last remaining data to arrive from the South Pole and expects to have results early in the new year.

Read more here

A Year of Celebration

Celebrating Innovation

Innovation150 – a part of Canada 150 celebrations – was led by Perimeter, with the Power of Ideas Tour visiting cities and towns across the country. More than 100,000 people attended tour events and many more attended talks, festivals, and other Innovation150 experiences.

Read more here

Celebrating Women in Physics

Perimeter’s Emmy Noether Initiatives continued to celebrate and support women scientists throughout the year. A free, downloadable poster series also shone the spotlight on some women pioneers in physics.

Read more here.

Continue the Journey

Advances in creating quantum light, determining what dark matter isn’t, sharing the wonders of science – Perimeter was a bustling hub of research, education, and outreach in 2017. Read more at www.insidetheperimeter.ca.

Thank you for joining us on this journey. We look forward to sharing more exciting news with you throughout 2018.

With appreciation,

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Jacqueline Watty
Senior Advancement Officer
Perimeter Institute for Theoretical Physics
519-569-7600 ext. 4472

See the full article here .

Please help promote STEM in your local schools.

STEM Icon

Stem Education Coalition

About Perimeter

Perimeter Institute is the world’s largest research hub devoted to theoretical physics. The independent Institute was founded in 1999 to foster breakthroughs in the fundamental understanding of our universe, from the smallest particles to the entire cosmos. Research at Perimeter is motivated by the understanding that fundamental science advances human knowledge and catalyzes innovation, and that today’s theoretical physics is tomorrow’s technology. Located in the Region of Waterloo, the not-for-profit Institute is a unique public-private endeavour, including the Governments of Ontario and Canada, that enables cutting-edge research, trains the next generation of scientific pioneers, and shares the power of physics through award-winning educational outreach and public engagement.

#celebrating-innovation, #celebrating-women-in-physics, #continue-the-journey, #eht-event-horizon-telescope, #multi-messenger-astronomy, #perimeter-institute, #recent-perimeter-news, #the-centre-for-the-universe

From Nautilus: “This Physics Pioneer Walked Away from It All”

Nautilus

Nautilus

July 28, 2016
Sally Davies
Illustrations by Ping Zhu
Photography by Tom Jamieson

Inside the South London offices of Doppel, a wearable technology start-up, sandwiched into a single room on a floor between a Swedish coffee shop and a wig-making studio, CEO and quantum physicist Fotini Markopoulou is debating the best way to describe an off-switch.

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Doppel: the wearable heartbeat that works with your body

Markopoulou and her three co-founders have gathered in convivial discomfort around a cluttered formica table and lean-to blackboard. They’re redesigning the features of their eponymous first device, which is due to be released in October. It’s a kind of elegant watch that sits on the inside of your wrist and delivers a regular, vibrating pulse. By mimicking a heartbeat, the Doppel helps regulate a person’s emotions and mental focus.

Swiveling in a chair, Markopoulou says she likes a “smothering” gesture—placing a palm over the face of the Doppel to turn it off—because it is intuitive and simple, and the term suggests the device is “alive.” “You could always murder it,” deadpans commercial director Jack Hooper. Head of technology Andreas Bilicki chimes in. “Why not ‘choke’ or ‘asphyxiate’?” The team throws around alternatives: “throttle”; “go to sleep, to sleep”; “turn your Doppel off, just like putting a blanket over a parrot’s cage.”

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A NEW BEAT: Fotini Markopoulou at work at Doppel, the wearable technology startup she co-founded, after saying goodbye to theoretical physics.

Markopoulou, 45, observes the banter with a half-smile. She is fine-featured and striking. Her heavy-lidded eyes anchor a gaze that seems wary of its own powers, as if her promiscuous intelligence must hold itself back from latching on to your every word. She wears her hair in a tousled pixie-cut, and on this spring day, a green knit sweater and blue scarf with a pattern of fish-like scales. There are no airs about her, nor any indication that she’s 20 years older than the rest of the team. Markopoulou lives in Oxford but sleeps on design director Nell Bennett’s couch whenever she comes down to London.

After the meeting, Markopoulou and I walk downstairs to get a coffee. With the zeal of the reborn, she tells me how much she relishes the pleasures of making a product that people will use and pay for. “There is a very 
practical satisfaction to getting stuff done, whether it’s making something or selling something,” she says. “I do enjoy solving practical problems, like how to convince people Doppel’s a good idea, or how to get the right deal from an accountant.”

It’s hard to see how these tasks could fully absorb Markopoulou. She is one of the most radical and fiercely creative theoretical physicists alive today, and a founding faculty member of the Perimeter Institute for Theoretical Physics in Waterloo, Canada, where she was at the vanguard of quantum gravity.

Perimeter Institute in Waterloo, Canada

This is the branch of physics striving to unify the two most fundamental theories of the universe: general relativity, proposed by Einstein, and quantum mechanics.

Quantum theory describes the rowdy interactions of fundamental particles that govern many of the forces in the known universe—except gravity. Gravity is rendered beautifully predictable by general relativity, which envisions it as an effect of how the four dimensions of space and time curve in response to matter, like a piece of tarpaulin bending under a bowling ball. Quantum theory’s ability to predict the behavior of an electron in a magnetic field has been described as the most precisely tested phenomenon in the history of science. But putting it together with gravity has so far produced absurd mathematical results. It’s as if a soccer player and a tennis player were managing to carry on a game despite being ignorant of the opponent’s rules.

After years of single-minded study, Markopoulou co-created a novel potential solution known as “quantum graphity.” This model of the universe operates at a scale that is tiny even by subatomic standards—as tiny in relation to a speck of dust as a speck of dust is to the entire universe. It suggests that space itself and its attendant laws and features could evolve out of interconnected dots to create the dimensions we experience as space, like a soufflé rising from a pan.

“Fotini is extremely original, original to a fault,” says Lee Smolin, a fellow founder of Perimeter who used to be married to Markopoulou. “Most scientists pick up on ideas which are dominant, which come from living figures, and develop them incrementally. She doesn’t do that—she works solely on her own ideas.”

Between sips of a latte, Markopoulou describes how theoretical physics consumed her. “It’s a lot like being in a monastery, like no normal human needs should make you waver from the cause of understanding where the universe came from,” she says. “In my previous eyes, just leaving is a moral failure, more than anything else. It’s a devotion thing—your devotion has just gone.” She pauses to shape her next thought. “It’s also not really a loss of faith; I changed.”

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GOT RHYTHM?: Markopoulou oversaw the design and engineering of the Doppel, which sends a mood-affecting pulse to a wearer’s wrist, from prototype to product.

Five years after walking away from physics, Markopoulou is still trying to explain that change to herself. She was forced to re-examine her position when Perimeter’s new director, Neil Turok, who joined in 2008, deemed her work too speculative and squeezed her out of the Institute. But her unease had deeper roots.

Working in a field where the air of reality was so thin, Markopoulou started to lose touch with her own life. “I have so many friends in their late 40s, and they still don’t have an actual home or a family or anything. As long as they have a place where they can go and think they’re happy.” She casts a wry smile. “I failed that test, obviously. For a lot of people that makes sense, and even for me that makes sense 80 percent. It’s that other 20 percent that causes problems.”

Doppel embodies many of the qualities that Markopoulou came to miss in her work as a physicist. The company is grounded in psychophysiology, a field which considers the mind to be deeply rooted in the body and its environment. But embracing the fact that the self is interwoven with the world, and at its mercy, is a frightening thought, Markopoulou says. Escaping that fear, and trying to pin down the interconnection between humans and the natural systems that make us what we are, is what drew her to physics in the first place.

“I did appreciate, for a long time, the way science detaches you from that scariness, because you ignore it,” Markopoulou says. “Between the truth of the physical world and a physics theory, there’s humans. Of course, nothing happens there, because removing the person is the whole point of training as a scientist.” A pause. “But this may or may not be possible.”

As a teenager growing up in Athens, Greece, Markopoulou looked like an ordinary kid: permed hair, heavy ribbed sweaters, a penchant for Clint Eastwood Westerns. But she was already attracted to the study of transcendent truths. On her way home from school, she would sometimes drop in at Greek orthodox churches to lie on her back in the pews, and contemplate the elaborate scenes of stars and angels painted into the interior domes. One summer, when she was 15, she happened across a book in the library of the British Council with the title Starseekers, a quasi-mystical account of the history of cosmology, by English writer Colin Wilson. “I got totally obsessed with that book,” Markopoulou says. She convinced her mother, Maria, to buy her an Atari computer, and spent hours trying to translate Starseekers into Greek on a word processor.

Markopoulou lived with her mother in a cramped two-story studio in Athens, where Maria worked as a figurative sculptor. She was a magnetic, troubled figure, unafraid to set her own moral compass but riven with internal conflicts. She’d fallen pregnant one summer to a Greek sculptor she had known in Florence, where she trained as an artist against the wishes of her parents, and decided to raise the baby as a single mother in Athens. She was 33. “Her lovely way of putting this was, ‘Jesus was also 33 when he was put on the cross,’ ” Markopoulou says. “But it was also very clear that I was the best thing that had ever happened to her.” (Markopoulou has never met and knows little about her father, who died in 1997.)

Markopoulou loved accompanying Maria to exhibitions and openings, but struggled to disentangle her sense of self from her mother’s strong and particular judgments. “My mother’s relation with reality, it would be wrong to say that it wasn’t solid, but it was just different,” Markopoulou says. Maria hated to sleep and refused to have a bed: “My mother clearly thought that sleeping was like dying, and that she might not wake up if she did, and something like a bed might as well have been a tombstone. I did realize as I was growing up that you couldn’t rely on her description of something.”

The subjectivity of aesthetic merit troubled Markopoulou. “One of the things I hated about the art-world is that decision-making is quite arbitrary,” she says. “People could say Picasso is shit just because they felt like saying it. I found that very frustrating, and very political; they’re gatekeepers, and then your life and self-perception is a function of those gatekeepers.”

Markopoulou’s education in Greece was “a complete disaster,” she says, with teachers whose instruction consisted of reading the newspaper at the front of the classroom. In her final year of high school, Markopoulou went in search of private evening classes; by mistake, she walked through the door of an institution that offered A-levels, the exams for students entering the British university system. She hadn’t considered studying in the United Kingdom, but ended up enrolling. “The usual story about people in quantum gravity is, ‘I read about Einstein when I was 8,’ ” she says. That was not her. The pendulum for her imaginary career had swung between being an astronaut and an archeologist. She only selected theoretical physics under the pressure of her university application, and chose the course on the casual advice of a tutor at the school, a former NASA scientist, who said it would be a good balance for her aptitude in physics and mathematics.

Markopoulou failed her A-levels—“the first time I walked into the lab was for the exam, and half the questions I answered in Greek”—but, as part of the clearing process between teachers and universities, her tutor secured her a place at Queen Mary’s University in London, her first choice. The department had several excellent particle physicists investigating the top quark, but the place retained the welcoming atmosphere of institutions unburdened by hallowed reputations.

Money was tight, so Markopoulou didn’t have much of a social life. She planned birthday parties at McDonald’s for a bit of extra cash, while her mother, who was living with her in London to get the rent from her studio in Athens, repaired antiques. (They would continue to live together until the last year of Markopoulou’s Ph.D.) But Markopoulou loved it all the same. She and a clutch of the other undergraduates would relax in the chapel café between lectures, and occasionally head out in the evenings to hear one of their professors play amateur hard rock. At the same time, in her classes, she got wind of the fact that “there was some forbidden place”—that when it came to certain subjects, such as why time moves in one direction, it was better not to ask. She was not content with what the rules were; she wanted to know how they came to be.

Toward the end of her undergraduate degree, a friend suggested Markopoulou attend a lecture on quantum gravity by Chris Isham, a rigorously mathematical physicist at Imperial College. He was also a Jungian analyst and devout Christian, with the air of a mystic and a fondness for peppering his lectures with passages from T.S. Eliot and Heidegger. “You can’t take out of the world the fact we see it,” Isham tells me. “What is the reality we hang onto? Well, it’s us, but who are we that sit inside this space which is relative to us?”

Isham was the first person Markopoulou encountered who could relate the technical dimensions of science to humans’ wider search for meaning. “Sometimes doing physics can be a bit like doing plumbing—you have your equations and tools and you go around and fix stuff, and if you do it in a smart way, people respect you,” she says. “Because you are a professional physicist, you get used to the idea that there are difficult questions that you do not do for a living. But these are what drove most of us to join the ranks.”

Markopoulou was developing her own clear vision of what she wanted to achieve as a physicist. “I am not going to devote my life to something because it’s beautiful—it’s this quest for the truth,” she says. “Science is not philosophy—there is not a lot of value in thinking about questions if you cannot come up with answers. But I’ve always been attracted to what is the furthest away you can get such that you can still come back with an answer. You’re trying to find the end of the coil to unfold it.”

Under Isham’s influence, Markopoulou started to grapple with quantum gravity. Her assigned Ph.D. project was based on a previous paper that examined the movement of dust particles to develop a new approach to splitting time away from the three dimensions of space. This sounds like a solution in search of a problem—surely time is a different thing from space?—until you remember Einstein’s counterintuitive insight that time is intimately interwoven with the fabric of space, and can be similarly twisted and bent by matter and movement. Time is dynamic, and defined by its relationship to what’s happening around it. It follows that there is no absolute time that the whole universe obeys—and more troublingly, when you push the equations far enough, time has a tendency to disappear entirely. “The relativity view of the world is that space and time is out there and it’s more or less a static thing—time is just another dimension,” the distinguished physicist Roger Penrose explains to me.

However, Einstein’s account of time doesn’t make sense in quantum theory. The quantum realm is host to all sorts of phenomena—particles existing in two places at once, or becoming entangled, as if they’re able to communicate their properties instantly and seemingly telepathically, whether separated by a lab-bench or a light-year. It adopts a version of time that’s far more conventional, like a metronome ticking away in the background, distinct from the bizarre behavior of quantum theory’s zoo of quarks, bosons, and fermions.

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DESIGN NOTES: When she worked on quantum gravity, Markopoulou gave many presentations with graphics. Likewise at Doppel, she and her colleagues post notes to visualize and solve problems.

It began to dawn on Markopoulou that you might be able to reconcile these two accounts of time by looking more closely at how they viewed space. After her first paper on dust modeling, she turned to spin networks. These are geometric models which help physicists describe quantum interactions in space, and fit more readily with the mathematics of general relativity. Markopoulou had the idea of combining spin networks with a “causal set,” which allows time to be captured as a history of discrete events rather than a continuous flow. Showing how histories could be represented spatially let her bring a more substantive version of time into general relativity—one that wasn’t rigid (as in some accounts of quantum theory) nor completely flexible (as in general relativistic spacetime).

Her work caught the eye of Smolin, an American theoretical physicist who at the time was visiting Imperial from Penn State University. He’d made a name for himself as a joint inventor of loop quantum gravity theory—a competitor to string theory in the quantum gravity sweepstakes—which was building on spin networks to develop a more sophisticated picture of quantum spacetime. Smolin worked with Markopoulou on a paper on causal sets, and invited her back to Penn State for three months while she was finishing her dissertation. They would marry in 1999.

At the time, Penn State was a premier institution for non-string quantum gravity, and Markopoulou was surrounded by a number of other brilliant young scientists. “A bunch of different ideas were coming together; there was this sense that you might actually do something faster than the person in the next room, which is very unusual in quantum gravity,” she says. String theory had never appealed to Markopoulou, who saw it as cutthroat and conformist. “String theory has a very strong pecking order,” she says. “It comes with a strong machismo: What complicated stuff can you do? They’re very good at maintaining that.”

Some of Markopoulou’s contemporaries saw the equations pointing to the conclusion that time is an illusion at the fundamental level, and that what we experience as the progression of events emerges as a byproduct of fluctuations in space. But Markopoulou tended to attack the problem from the other direction—looking at time as the most important thing, and space as something that grows out of it, or is left as a trace, like a logbook of what has taken place in time. “I’m a bit extreme in that I would actually like to keep a fairly old-style time,” Markopoulou says. “I’m not wrong in my views. They come with challenges, but they also come with opportunities.”

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IN HER ELEMENT: At the Perimeter Institute for Theoretical Physics, where she was a founding member, Markopoulou, seen here in 2002, was known as a persuasive, though not forceful, leader. Derek Shapton

In early 2000, whispers went around the theoretical physics community that somebody wanted to donate $100 million for an institute dedicated to foundational physics. Markopoulou and Smolin were approached by Howard Burton, a Canadian with a Ph.D. in theoretical physics from the University of Waterloo, who was the emissary for this Gatsby-like figure. “I genuinely thought the guy was a sociologist studying the reactions of physicists to that statement—the amount of money is crazy for foundational physics,” Markopoulou says. By now she was doing a postdoctoral fellowship at the Max Planck Institute for Gravitational Physics in Berlin. She and Smolin were flown in secrecy to Canada and only informed that the donor was Mike Lazaridis, the founder of Blackberry, on the drive from the airport: “We spent the night at Mike’s house, where he made us French toast and talked us into coming to Waterloo.”

By the time Perimeter was set up, she and Smolin had separated, but remained friends—which was just as well. To lay the scientific groundwork for the institute, the three founding faculty huddled together in a former restaurant, along with several postdoctoral students and Burton, whom Lazaridis had appointed as the director. They inherited the coffee machine and learned to make top-notch barista cappuccinos. The institute aspired to a flat management structure hospitable to free-thinkers, without tenured jobs or the ordinary hierarchies of a university physics department, in the hope that this would foster more interesting research.

While Markopoulou was not a forceful leader, she was a persuasive one, says Seth Lloyd, a physicist and professor at the Massachusetts Institute of Technology, and a longtime collaborator of Markopoulou’s. He recalls trekking with her and some postdocs in the Sangre de Cristo Mountains, when she was on a fellowship at the Santa Fe Institute in New Mexico. “At each stage of the hike, there were different suggestions about where to go, and we always ended up doing what Fotini thought was a good thing,” he says. “We had a great time, none of us ever thought Fotini was imposing her will—just that what Fotini seemed to want to do was the right thing to do.”

At Perimeter, Markopoulou was at her best when the learning and experimentation were the quickest. Invariably her work became playful and synthetic. “At some point I thought we should just reduce the whole thing to the basic property of space, which is here and there,” she says. Physicists were willing to toy with the nature of time and “hack” general relativity to create a quantum gravity theory, she says. But they seldom played with the nature of space or “hacked” quantum theory. With Simone Severini, an Italian computer scientist, and graduate student Tomasz Konopka, Markopoulou drew on quantum information theory to develop the notion of quantum graphity. “Fotini thought it was fun—this cute idea, that the universe is a big network, like the London Underground, that changes over time,” Severini says.

Markopoulou was partly inspired by the principle of emergence, where complexity can emerge from simplicity, or, more to her point, simplicity from complexity, such as wiggling water molecules forming ice crystals or waves. Paramount in her model was the ability to create images that explained “geometrogenesis,” her and her colleagues’ term for the emergence of the structure of spacetime during a critical phase in the birth of the universe. “Once it starts being hard to visualize, I’m not happy, I get uncomfortable,” she says. “I also think you can have an extreme richness while staying with very few building blocks.”

She was tickled by an aperçu from Ludwig Boltzmann, the 19th-century Austrian physicist, who looked at the physical properties of atoms and said, “Every Tom, Dick, and Harry felt himself called upon to devise his own special combination of atoms and vortices, and fancied in having done so that he had pried out the ultimate secrets of the Creator.” Markopoulou chuckles. “It felt to me, when we were arguing ‘Is it my model? Is it your model?’ we were totally every Tom, Dick, and Harry.”

In quantum graphity, space evolves out of dots that are either “on” or “off ”—connected or disconnected to the next dot. It doesn’t matter exactly what the dots are; they represent coordinates in a network of relationships, the fundamental constituents of the universe. The idea, Markopoulou explains, comes from a branch of mathematics known as category theory, in which “what something is, is the sum of how it behaves, rather than how it is.” At the highest possible energy, at the beginning of the universe, all the dots in the graph are joined, and no notion of space exists. But as the system cools and loses energy, the points start detaching, which creates the dimensions and laws of space. In this model, space becomes like a crystal that forms out of a liquid as it cools. “The value of this is in trying to give, however primitive it might be, some language to talk about space not being there,” she says.

“It was very courageous of Fotini to start working on this,” says Sabine Hossenfelder, a research fellow at the Frankfurt Institute for Advanced Studies, a think tank devoted to theoretical physics, who from 2006 to 2009 did postdoc work at Perimeter. “It’s the kind of thing you think has been done long ago, but surprisingly it wasn’t.” It would have been much easier, Hossenfelder says, for Markopoulou to find a niche for herself within an existing theory, like loop quantum gravity. “But quantum graphity of course is much more exciting. It’s a new idea, one that could have done a good job bridging the gap between theory and experiment.”

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No image caption. No image credit.

As Markopoulou’s reputation grew, she was often called upon to represent Perimeter to the public. She was a young, accomplished woman in physics—a rarity. She enjoyed and tended to accept speaking invitations, partly to help change perceptions of female scientists. “For previous generations, the question was ‘Are there women in science?’ Now there are, but girls want to know, ‘Are they normal?’ When you seem to be happy, and you seem to be a woman they’d be happy to be, that’s a fairly big thing.” Her world revolved around quantum gravity. Shortly after separating from Smolin, she had fallen into a relationship with a German postdoctoral fellow at the institute, Olaf Dreyer, whom she married after four years. They lived and breathed their discipline. “It’s nice to share these things with somebody closely,” she says.

But Markopoulou found her more radical theories were sometimes greeted with the sly criticism that they were “creative.” “The fact that you don’t look like the standard makes it hard for them; they will take longer to form judgments, which means you stay in the doubt area for longer,” she says. It was made worse by the pervasive attitude among physicists that you should gather your laurels by doing sensible calculations throughout your career, and only cook up new theories of quantum gravity in your old age.

Markopoulou refused to play that game, and a sense of discontent began to build. Every problem she solved created a quagmire of fresh ones; and, daughter of sculptors, she was tiring of academic papers as the only tangible thing she could “make.” After a while, even her public-facing activities began to grate. “There is a part of me that felt like a kind of clown, telling people magical things about the universe,” she says. “Something you take very seriously and you’ve devoted your life to, and you’ve made your own sacrifices for, is, for other people, at best entertainment.” She consoled herself with something Isham once told her, counsel he’d received in turn from the physicist John Archibald Wheeler. When it comes to quantum gravity, he says, you’re bound to fail. “What’s important is not the fact you fail, but how you fail.” Markopoulou was determined to fail better, to borrow Samuel Beckett’s phrase.

In 2008, the South African physicist Turok was appointed director of Perimeter. Turok, who describes himself as “very demanding,” pulled back from the more outré flavors of foundational physics and expanded into other areas, including particle physics, cosmology, and quantum computing. He didn’t want the institute, he says, “to be center for alternative physicists who were doing unusual things in speculative directions.”

By 2009, Markopoulou’s personal life was undergoing its own quantum transitions. At a conference in Waterloo about physics and the financial crisis, organized by Smolin, Markopoulou met systems theorist and physicist Doyne Farmer. The pair was instantly dazzled by one another, and within five days decided to upend their lives to be together. Markopoulou separated from Dreyer and Farmer from his wife. Not long after, she got pregnant on a road trip from San Francisco to Santa Fe in Farmer’s 1967 Datsun convertible. Their son, Maris, was born in 2010; a year later, Markopoulou’s mother Maria passed away.

Markopoulou was still attracted to deep inquiry, but the further down she went, the less objective she found her colleagues’ judgments about the value of her work. “If you’re in a place where everything is certain, that’s a very boring place,” she says. “But if you jump out with no parachute, it’s either a sociological exercise or a folly.” She’d been striving to position her research at the metaphorical “edge of chaos,” the point at which order emerges from complexity. But she’d started to get the creeping suspicion she was back with the artists in her mothers’ studio, competing for recognition and influence without any clear standards.

“In the absence of any kind of experimental confirmation or the ability to falsify your theories, quantum gravity has ended up being dominated by a few influential tastemakers,” says Lloyd. “Fotini fell foul of that because she had her own strong sense of what is a good thing to do; her tastes were different.”

As the institute continued to grow, Turok faced the challenges of needing to formalize its processes and manage larger numbers of physicists. Perimeter had already begun the process of implementing tenure for its faculty, which Turok inherited. Markopoulou prepared to apply. By this time she was back in Berlin again, on a fellowship at the Max Planck Institute. She put together a dossier of her accomplishments for Turok, which was also to be reviewed by a tenure committee and quantum gravity experts.

Turok says he respected Markopoulou, but doubted her work would lead anywhere. He denied her tenure. “Fotini had pursued a very independent line of inquiry that was really very different and hardly acknowledged by leading researchers in the field,” Turok says. “I applauded her for her bravery for pursuing her own line, but that inevitably brings risks with it. She is a very fundamental thinker; she had original ideas. But at the end of the day you had to decide if those ideas are going to pan out.”

Markopoulou says she was disappointed that Perimeter had “shifted from a flat hierarchy of scientists to an all-powerful director.” Turok emailed her out of the blue, she says, to stop the review process and deny her tenure. “As a result of my case, an independent consultant was appointed because I had been the only woman faculty for nine years, I had a strong academic record, and Neil stopped the tenure process just as I had a baby,” Markopoulou says. (“I respectfully beg to differ,” Turok responds. “A tenure review process was never initiated.”) The matter is subject to an out-of-court settlement.

In the autumn of 2011, Markopoulou walked out of Perimeter for good.

One sunny morning in March, I visit Markopoulou at her home outside Oxford, perched on a hill and encircled by stands of oak, ash, and silvery birch. Nancy, the wife of the poet and classicist Robert Graves, used to run a grocery store on the site before the poet John Masefield knocked it down to build a theater in 1924. The top rooms sit snug under the original proscenium arch. Markopoulou loves theater—a legacy of being Greek, she says. It allows you to “step out of your normal shoes, to shift reality a bit, and to actively participate by forcing you to suspend your belief.” Not unlike science at its highest levels.

In the living room, Markopoulou bundles herself up into a burgundy armchair with the cheerful self-possession of a family cat. A Persian rug sprawls across the wood floor, monopolized by a Lego space station. One of her mother’s bronze busts broods from a windowsill, a beautiful, dauby figure of a woman with braids parted down the middle. “You were asking me the other day what made me change,” she says. “One big thing was my mother died and opened up a space for me.” Markopoulou wouldn’t have touched art while her mother was alive, but recognizes now that a similar desire to make, to craft and to create, is part of who she is.

“In many ways, physics and what I did are almost ideally positioned to my experience with my mother,” she says. “I probably did come out of that wanting a much more firm grasp of what is what, and objective decision-making. Now I don’t feel I need that much any more, but growing up that was a big deal. Also, it was far away from her, it was my own space, but at the same time there were many ways in which the deeper challenges are the same.” Sculpture is a lot like creating a physics theory, she says, because you have to turn it around and make sure it works from every angle. “You have to understand the essence of what you’re doing before you start, because only then do you have a chance that it’s going to work from all sides.”

Did she believe this philosophy could help her solve quantum gravity? “I never really wanted to single-handedly solve it. But I never went in thinking that we can’t. I always assumed it was possible.” Does she still think it is? “Not soon, but I don’t know. If I knew, I would be doing it,” she quips.

During her unsteady transition out of physics, Farmer was a pillar of support for Markopoulou. “I’m very much what I do, so going through a transition is a time when I don’t know who I am,” she says. “I was lucky to have the context where that was perfectly possible.”

Farmer is a distinguished and idiosyncratic physicist in his own right. While still in grad school at the University of California, Santa Cruz, studying physical cosmology, he and fellow physicist, Norman Packard, created one of the world’s first wearable computers. Released in the 1970s, it was a toe-operated device embedded in the tip of a shoe, which allowed the wearer and an accomplice to track the progress of a roulette ball and achieve a 20 percent advantage over the house. He and Packard later decided to found one of the first predictive stock trading companies, which was ultimately sold to UBS, a financial services company, in 2006. Farmer’s interests now lie in “econophysics,” a field which he founded and which applies the mathematics of natural systems to gather insights about the economy.

When Farmer landed a post at Oxford University in 2011, Markopoulou was faced with “the usual two body problem in academia” of trying to find a job nearby. But when she started looking, she realized her heart wasn’t in it. She had been toying with industrial design, and asked the advice of the musician Brian Eno, a physics follower and a friend. He advised her to look into the master’s program in Innovation Design Engineering run by the Royal College of Arts and Imperial College in London, and wrote her a letter of reference.

She sailed through the admissions process, which included an exercise where prospective students had to explain how they would evade a pack of zombies chasing them toward the lip of a cliff. She enjoyed the classwork but found the mental shift hard at first. “It just felt silly because you go from, ‘This is how the universe started’ to, ‘This mattress has these bubbles.’ ”

But she loved making things, and also made the personal connections that evolved into Doppel. A sailing trip to Greece, in which the Doppel crew nearly scuppered Markopoulou’s and Farmer’s large-bottomed boat on the rocks off the island of Cephalonia, cemented the team’s conviction that they could withstand the trials of doing a start-up.

The kernel for Doppel came from a piece in New Scientist about interoception—the way humans can discern the internal states of the body and conceive of it as “their own.” The idea is that our sense of self is not merely a mental process that somehow envelops the body, but somehow arises from the two-way conversation between the brain and other organs. As Manos Tsakiris, the softly spoken psychologist and neuroscientist who advises Doppel, tells me, “You cannot cut off cognition from the rest of the body, and you cannot cut off the body from the rest of the world in which you interact.” By harvesting your natural response to rhythm, Doppel runs counter to the notion that the self resides in the mind alone—that the human is a creature of the will, a maker of rational decisions, a sovereign mind bossing around dumb matter.

With hindsight, Markopoulou sees her work at Doppel as a “natural evolution” from what she did before. Isham had inspired her to pursue physics as a quest to understand reality from within, when scientists can’t stand apart from what they’re trying to analyze. But now, instead of the universe as the ultimate system, she has the human body. “If you think about physics, it’s a human creation. The equations represent stuff we come up with because of our senses. So shouldn’t our senses be part of what goes into physics?” Markopoulou says.

Markopoulou thinks that many disputes in science come down to competing metaphysical commitments. She recognizes that her own belief in the fundamental nature of time, and her dislike of timelessness, is a moral preference as much as anything else. “Most of the physics where time does not exist comes with determinism as well. There is something about thinking that time is real and being responsible for your actions,” she tells me.

This belief in the inexorable movement of time is what seems to have allowed Markopoulou to reinvent herself—to turn away from years spent building a career as a physicist and to start from scratch as a designer and entrepreneur. “This is the nice thing about me, but it’s also a little bit weird: When I do something, I just do it. So when I switched, I switched,” she says. “Our mind can live in the past, the future, or any fantasy place it wants, but our body only processes the now.”

Doppel is unlikely to be the end of Markopoulou’s journey. “Whatever it is that you do, it has to have a context. Academia is one context, business is another context. I can’t really tell you if it’s better or worse, it’s a different set of rules—and right now I have come to no conclusions as to what I think about those rules. I’m still exploring.”

See the full article here .

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Welcome to Nautilus. We are delighted you joined us. We are here to tell you about science and its endless connections to our lives. Each month we choose a single topic. And each Thursday we publish a new chapter on that topic online. Each issue combines the sciences, culture and philosophy into a single story told by the world’s leading thinkers and writers. We follow the story wherever it leads us. Read our essays, investigative reports, and blogs. Fiction, too. Take in our games, videos, and graphic stories. Stop in for a minute, or an hour. Nautilus lets science spill over its usual borders. We are science, connected.

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From PI: “What We Know (And What We Don’t) About Dark Matter”

Perimeter Institute
Perimeter Institute

June 29, 2016

Eamon O’Flynn
Manager, Media Relations
eoflynn@perimeterinstitute.ca
(519) 569-7600 x5071

Some of the most abundant stuff in the universe is also the most mysterious, but we may not be in the dark for long.

The concept of dark matter is a mind-bender.

It proposes that all the stuff we’re familiar with in the universe – planets, stars, galaxies, hippopotamuses – represent just a smidgen of what’s really out there, and that the universe is mostly populated by something else that we don’t yet understand.

The existence of this abundant-but-elusive stuff is inferred by the gravitational sway it seems to exert on what we can see, and on the large-scale structure of the universe.

So what is it? Well, we’re still largely in the dark, but much research aims to shed light on the matter.

Here’s a look at what we know, and what we don’t, about one of the greatest mysteries in modern physics.

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Check out Perimeter Institute’s educational resource, The Mystery of Dark Matter.

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Watch an excerpt about Fritz Zwicky from a Perimeter Institute Public Lecture by Katherine Freese.

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Weakly interacting massive particles (WIMPs) are a leading candidate for dark matter. Wimpzillas are, as the name implies, supermassive WIMPs. Other candidates include robust associations of massive baryonic objects (RAMBOs), gravitinos, and massive astrophysical compact halo objects (MACHOs). Less catchy, but equally intriguing, are the axion and the Kaluza-Klein particle.

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Watch a public lecture by Perimeter researcher Kendrick Smith about what we have learned from the CMB.

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Check out this Business Insider article on the physics of Super Mario World.

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Watch “The Dark Side of the Universe,” a Perimeter Institute Public Lecture by Katherine Freese, delivered March 2, 2016.

Access mp4 video here .

See the full article here .

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About Perimeter

Perimeter Institute is the world’s largest research hub devoted to theoretical physics. The independent Institute was founded in 1999 to foster breakthroughs in the fundamental understanding of our universe, from the smallest particles to the entire cosmos. Research at Perimeter is motivated by the understanding that fundamental science advances human knowledge and catalyzes innovation, and that today’s theoretical physics is tomorrow’s technology. Located in the Region of Waterloo, the not-for-profit Institute is a unique public-private endeavour, including the Governments of Ontario and Canada, that enables cutting-edge research, trains the next generation of scientific pioneers, and shares the power of physics through award-winning educational outreach and public engagement.

#basic-research, #dark-matter, #perimeter-institute

From PI: “New Experiment Clarifies How The Universe Is Not Classical”

Perimeter Institute
Perimeter Institute

June 17, 2016
Erin Bow

“This is a great example of what’s possible when Perimeter and IQC work together. We can start with these exciting, abstract ideas and convert them to things we can actually do in our labs.”
– Kevin Resch, Faculty member, Institute for Quantum Computing

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From left to right: Matthew Pusey (Perimeter postdoctoral researcher), Kevin Resch (IQC and University of Waterloo faculty member), Robert Spekkens (Perimeter faculty member), and Michael Mazurek (University of Waterloo and IQC PhD student) interact in a quantum optics lab at the Institute for Quantum Computing. No image credit.

Theorists from Perimeter and experimentalists from the Institute for Quantum Computing have found a new way to test whether the universe is quantum, a test that will have widespread applicability: they’ve proven the failure of noncontextuality in the lab.
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What does it mean to say the world is quantum? It’s a surprisingly difficult question to answer, and most casual discussions on the point are heavy on the hand-waving, with references to cats in boxes.

If we are going to turn the quantum-ness of the universe to our advantage through technologies like quantum computing, our definition of what it means to be quantum – or, more broadly, what it means to be non-classical – needs to be more rigorous. That’s one of the aims of the field of quantum foundations, and the point of new joint research carried out by theorists at Perimeter and experimentalists at the University of Waterloo’s Institute for Quantum Computing (IQC).

“We need to make precise the notion of non-classicality,” says Robert Spekkens, a faculty member at Perimeter, who led the work from the theoretical side. “We need to find phenomena that defy classical explanation, and then subject those phenomena to direct experimental tests.”

One candidate for something that defies classical explanation is the failure of noncontextuality.

“You can think of noncontextuality as the ‘if it walks like a duck’ principle,” says Matthew Pusey, a postdoctoral researcher at Perimeter who also worked on the project.

As the saying has it, if something walks like a duck and quacks like a duck, it’s probably a duck. The principle of noncontextuality pushes that further, and says that if something walks like a duck and quacks like a duck and you can’t tell it apart from a duck in any experiment, not even in principle, then it must be a duck.

Though noncontextuality is not something we often think about, it is a feature one would expect to hold in experiments. Indeed, it’s so intuitive that it seems silly to say it aloud: if you can’t tell two things apart, even in principle, then they’re the same. Makes sense, right?

But in the quantum universe, it’s not quite true.

Under quantum theory, two preparations of a system can return identical results in every conceivable test. But researchers run into trouble when they try to define exactly what those systems are doing. It turns out that in quantum mechanics, any model that assigns the systems well-defined properties requires them to be different. That’s a violation of the principle of noncontextuality.

To understand what’s happening, imagine a yellow box that spits out a mix of polarized photons – half polarized horizontally and half polarized vertically. A different box – imagine it to be orange – spits out a different mix of photons, half polarized diagonally and half polarized anti-diagonally.

Now measure the polarization of the photons from the yellow box and of the photons from the orange box. You can measure any polarization property you like, as much as you like. Because of the way the probabilities add up, the statistics of any measurement performed on photons from the yellow box are going to be identical to the statistics of the same measurement performed on photons from the orange box. In each case, the average polarization is always zero.

“Those two kinds of boxes, according to quantum theory, cannot be distinguished,” says Spekkens. “All the measurements are going to see exactly the same thing.”

You might think, following the principle of noncontextuality, that since the yellow and orange boxes produce indistinguishable mixes of photons, they can be described by the same probability distributions. They walk like ducks, so you can describe them both as ducks. But as it turns out, that doesn’t work.

In a noncontextual world, the fact that the yellow-box photons and orange-box photons are indistinguishable would be explained in the natural way: by the fact that the probability distribution over properties are the same. But the quantum universe resists such explanations – it can be proven mathematically that those two mixtures of photons cannot be described by the same distribution of properties.

“So that’s the theoretical result,” says Spekkens. “If quantum theory is right, then we can’t have a noncontextual model.”

But can such a theoretical result be tested? Theorists from Perimeter and experimentalists from IQC set out to discover that very thing.

Kevin Resch, a faculty member at IQC and the Department of Physics and Astronomy at the University of Waterloo, as well as a Perimeter Affiliate, worked on the project from the experimental end in his lab.

“The original method of testing noncontextuality required two or more preparation procedures that give exactly the same statistics,” he says. “I would argue that that’s basically not possible, because no experiments are perfect. The method described in our paper allows contextuality tests to deal with these imperfections.”

While previous attempts to test for the predicted failure of noncontextuality have had to resort to assuming things like noiseless measurements that are not achievable in practice, the Perimeter and IQC teams wanted to avoid such unrealistic assumptions. They knew they couldn’t eliminate all error, so they designed an experiment that could make meaningful tests of noncontextuality even in the presence of error.

Pusey hit on a clever idea to fight statistical error with statistical inference. Ravi Kunjwal, a doctoral student at the Institute for Mathematical Sciences in Chennai, India, who was visiting at the time, helped define what a test of noncontextuality should look like operationally. Michael Mazurek, a doctoral student with Waterloo’s Department of Physics and Astronomy and IQC, built the experimental apparatus – single photon emitters and detectors, just as in the yellow-and-orange box example above – and ran the tests.

“The interesting part of the experiment is that it looks really simple on paper,” says Mazurek. “But it wasn’t simple in practice. The analysis that we did and the standards that we held ourselves to required us to really get on top of the small systematic errors that are present in every experiment. Characterizing those errors and compensating for them was quite challenging.”

At one point, Mazurek used half a roll of masking tape to keep optical fibres from moving around in response to tiny shifts in temperature. Nothing about this experiment was easy, and much of it can only be described with statistics and diagrams. But in the end, the team made it work.

The result: an experiment that definitively shows the failure of noncontextuality. Like the pioneering work on Bell’s theorem, this research clarifies what it means for the world to be non-classical, and confirms that non-classicality experimentally.

Importantly, and in contrast to previous tests of contextuality, this experiment renders its verdict without assuming any idealizations, such as noiseless measurements or statistics being exactly the same. This opens a new range of possibilities.

Researchers in several fields are working to find “quantum advantages” – that is, things we can do if we harness the quantum-ness of the world that would not be possible in the classical world. Examples include quantum cryptography and quantum computation. Such advantages are the beams and girders of any future quantum technology we might be able to build. Noncontextuality can help researchers understand these quantum advantages.

“We now know, for example, that for certain kinds of cryptographic tasks and computational tasks, the failure of noncontextuality is the resource,” says Spekkens.

In other words, contextuality is the steel out of which the beams and girders are made.

“This is a great example of what’s possible when Perimeter and IQC work together,” says Resch, Canada Research Chair in Optical Quantum Technologies. “We can start with these exciting, abstract ideas and convert them to things we can actually do in our labs.”

See the full article here .

Please help promote STEM in your local schools.

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About Perimeter

Perimeter Institute is a leading centre for scientific research, training and educational outreach in foundational theoretical physics. Founded in 1999 in Waterloo, Ontario, Canada, its mission is to advance our understanding of the universe at the most fundamental level, stimulating the breakthroughs that could transform our future. Perimeter also trains the next generation of physicists through innovative programs, and shares the excitement and wonder of science with students, teachers and the general public.

#institute-for-quantum-computing-u-waterloo, #noncontextuality, #perimeter-institute, #quantum-mechanics, #theoretical-physics, #what-does-it-mean-to-say-the-world-is-quantum

From PI: “Bridging Two Roads of Physics” Women in Science

Perimeter Institute
Perimeter Institute

May 30, 2016
Rose Simone

Recent Perimeter research based on the holographic principle seeks new connections between general relativity and quantum field theory.

Imagine driving along a road that traverses a beautiful landscape. Around every corner, there is a new vista of natural beauty to explore. Suddenly you come to a chasm.

You can see a road on the other side, but how do you get there to complete the journey? You need a bridge.

That’s the state of physics today, and Bianca Dittrich, Perimeter Institute researcher in mathematical physics and quantum gravity, is one of the people trying to build that bridge.

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Bianca Dittrich

On one side of the chasm is the road built by Albert Einstein’s theory of general relativity. It describes the force of gravity as the warping of spacetime by large masses such as planets and stars.

On the other side is quantum field theory, our best description of interacting particles and the three other forces (the strong and weak nuclear forces and electromagnetism) operating at minuscule subatomic distances.

The theories are incredibly successful in their respective realms, yet they are so different, both in formulation and conceptually, that it is difficult to bridge them.

“Basically, we are trying to bridge all of the scales that we know,” Dittrich says. “That is what physics is about, but it is very hard. You need to bridge all of these scales by modelling the tiny scales, and show that this model actually does indeed describe reality as we know it at macroscopic scales.”

In general relativity, spacetime is smooth and continuous. If you were to zoom in with a microscope to arbitrarily small distances, it should look the same as it does when you zoom out for the larger view. Quantum field theory, on the other hand, describes particles and forces that come as discrete “packets,” and spacetime would also have to be discrete and granular, like the pixels in a photograph.

Scientists need a theory to describe the force of gravity at the quantum scale, and it must be consistent with the larger picture of general relativity. Building the bridge to a theory of quantum gravity is what occupies many physicists around the world today.

It is easier said than done. If general relativity is scaled down to the quantum size, you start to get nonsensical “infinities” in the calculations. “Quantizing gravity sounds simple, in that it should be just the quantization of another force, besides the three forces (the non-gravitational forces) that were quantized decades ago,” Dittrich says. “But in fact it is a very hard and open problem.”

There are many approaches to this longstanding problem. In loop quantum gravity, for example, physicists speak in terms of “spacetime atoms” linked together in a network like a fine mesh. This provides a model of what spacetime itself is made of.

But in a recent paper*, “3D Holography: From Discretum to Continuum,” Dittrich and co-author Valentin Bonzom, now an assistant professor at Université Paris 13 who was previously a postdoctoral researcher at Perimeter Institute, tested a different approach, based on the holographic principle.

The holographic principle says everything that happens in a given space can be explained in terms of information stored on the boundary of that space. (The principle takes its name from holograms, in which two-dimensional surfaces contain all the information needed to project a three-dimensional image.)

A popular mathematical framework based on the holographic principle is known as the AdS/CFT correspondence. AdS is short for anti-de Sitter space, which describes a particular kind of geometry. Just like a bowling ball will stretch a rubber sheet, the elliptical shape of anti-de Sitter space can also stretch or contract, thus allowing it to describe gravity.

CFT, meanwhile, is short for conformal field theory. Field theories are the language of quantum mechanics and can describe, for example, how an electrical field might change over space and time.

The holographic principle applies because the AdS/CFT correspondence basically states that for every conformal field theory, there is a corresponding theory of gravity with one more dimension. So a two-dimensional CFT would correspond to a three-dimensional theory of gravity, for instance.

But the holographic principle applies to infinitely large boundaries, and Dittrich and Bonzom wanted to see if it could also hold for finite boundaries, and for other types of geometries apart from AdS. This would then provide a more manageable way of describing a piece of spacetime, and understanding the microscopic details as they reconstruct the spacetime bulk.

Working with a boundary without worrying too much about the bulk “very much simplifies the construction of a theory of quantum gravity,” Dittrich explains.

They tested this in three spacetime dimensions, and “it turned out that the holographic principle indeed holds for finite boundaries, and we also obtained a very simple description of how to translate the boundary data into the geometry of the bulk,” she says.

That this could be done in 3D was not too surprising, but the more challenging part will be extending this work into 4D space, Dittrich adds.

Most theories of quantum gravity require the force of gravity to also be mediated by hypothetical particles called gravitons. If Dittrich can get her model to work in 4D, then she will have successfully taken it into a realm where gravitons exist. “Gravity can propagate through that spacetime,” Dittrich says.

Dittrich has been on the physics road for some time. She grew up in Germany, reading a lot of popular books about science, as well as history and literature, and when she finished high school she considered various options, including areas such as geo-ecology.

But she realized it was physics that could take her on the journey to the most complete understanding of nature. “If you want to understand why something works, the answer is in physics,” she says.

Now, she is designing another bridge that will span that chasm between the two great roads and carry physicists to that more complete understanding of nature.

*Science paper:
3D holography: from discretum to continuum

See the full article here .

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About Perimeter

Perimeter Institute is a leading centre for scientific research, training and educational outreach in foundational theoretical physics. Founded in 1999 in Waterloo, Ontario, Canada, its mission is to advance our understanding of the universe at the most fundamental level, stimulating the breakthroughs that could transform our future. Perimeter also trains the next generation of physicists through innovative programs, and shares the excitement and wonder of science with students, teachers and the general public.

#basic-research, #perimeter-institute, #quantum-field-theory, #quantum-gravity, #relativity, #women-in-science

From The Globe and Mail via PI: “‘Brilliant’ physicist to hold $8-million research chair at Perimeter Institute”

Perimeter Institute
Perimeter Institute

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Apr. 28, 2016
IVAN SEMENIUK

Long before the February press conference where physicists reported the first detection of gravitational waves from space – a major scientific achievement that made headlines around the world – Asimina Arvanitaki had arrived at a way to do the same thing with a far smaller and cheaper experiment involving a microscopic disk suspended by powerful lasers.

The 36-year-old theorist, known to friends and colleagues as Mina, has become a specialist in thinking up novel approaches to some of of the deepest problems in fundamental physics. Her work is at the forefront of an emerging area of research that is sometimes called “the precision frontier” because it involves making exacting measurements of well-understood phenomena and looking for unexpected deviations from what theory predicts.

“Most of these ideas you can actually build on a table,” said Dr. Arvanitaki.

Now Dr. Arvanitaki will have more scope and resources to pursue her ideas as the latest recipient of an $8-million research chair at the Perimeter Institute for Theoretical Physics in Waterloo, Ont., where she has worked as a researcher since 2014.

The new chair is noteworthy for a few reasons. In addition to representing an area of research that thrives on working off the beaten track, Dr. Arvanitaki will become the first female chair holder at the high-profile institute and the first to be supported by a funding source from outside Canada.

The Stavros Niarchos Foundation, a philanthropic organization headquartered in Athens and associated with a shipping industry fortune, will cover half the cost of the chair with the remaining support coming from the Perimeter Institute.

Greek heritage is evident in the title of the new position, dubbed the Aristarchus Chair in Theoretical Physics after the ancient philosopher from the Greek island of Samos who famously suggested that the Earth revolves around the sun, some 18 centuries before Nicolaus Copernicus.

“His thinking implied the sun is exactly like the distant stars,” said Dr. Arvanitaki, who suggested the name for the inaugural chair.

She added that by foreseeing that our solar system many not be unique in the universe, Aristarchus was also setting the stage for a far more contentious theory in current physics, which holds that our entire universe is just one of many.

“It’s a very controversial idea. People hate it, but I find it fascinating,” Dr. Arvanitaki said.

Raised in a small village in southern Greece, Dr. Arvanitaki was the child of two teachers and grew up with an appetite for learning. She recalls that at a young age she correctly calculated the time it takes light to travel from Earth to the sun – about eight minutes – and was stunned to realize that “we cannot know the ‘now’ of the sun.”

Dr. Arvanitaki came to Perimeter after earning her PhD and doing postdoctoral work at Stanford University under Savas Dimopoulus, a widely respected theorist who also hails from Greece.

“She’s one of the most brilliant young people I’ve ever met,” Dr. Dimopoulos said of his former student and collaborator.

He added that intelligence alone was not enough for success in physics, and that one way Dr. Arvanitaki excels is in selecting problems to work on that lead to productive results.

“You have to have good taste,” he said. “Or in her case, even inventing new directions and new ways to see very well-motivated ideas.”

Dr. Arvanitaki said she was looking forward to bringing on more researchers and students to accelerate her efforts to explore new domains of physics, and was pleased at the prospect of doing it at the Perimeter Institute. “There’s something about this place – you feel it when you walk in the building – it’s intoxicating.”

The Institute was established in 1999 by BlackBerry co-founder Mike Lazaridis and has since drawn substantial government support, including a $50-million investment over five years announced in the latest federal budget.

Black holes merging Swinburne Astronomy Productions
Black holes merging Swinburne Astronomy Productions

See the full article here .

Please help promote STEM in your local schools.

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About Perimeter

Perimeter Institute is a leading centre for scientific research, training and educational outreach in foundational theoretical physics. Founded in 1999 in Waterloo, Ontario, Canada, its mission is to advance our understanding of the universe at the most fundamental level, stimulating the breakthroughs that could transform our future. Perimeter also trains the next generation of physicists through innovative programs, and shares the excitement and wonder of science with students, teachers and the general public.

#astrophysics, #basic-research, #gravitational-waves, #perimeter-institute, #the-globe-and-mail