A May 15, 2020 news item on Nanowerk provides context for an announcement of a research breakthrough on quantum entanglement,
Quantum entanglement is a process by which microscopic objects like electrons or atoms lose their individuality to become better coordinated with each other. Entanglement is at the heart of quantum technologies that promise large advances in computing, communications and sensing, for example detecting gravitational waves.
Entangled states are famously fragile: in most cases even a tiny disturbance will undo the entanglement. For this reason, current quantum technologies take great pains to isolate the microscopic systems they work with, and typically operate at temperatures close to absolute zero.
The ICFO [Institute of Photonic Sciences; Spain] team, in contrast, heated a collection of atoms to 450 Kelvin, millions of times hotter than most atoms used for quantum technology. Moreover, the individual atoms were anything but isolated; they collided with each other every few microseconds, and each collision set their electrons spinning in random directions.
The researchers used a laser to monitor the magnetization of this hot, chaotic gas. The magnetization is caused by the spinning electrons in the atoms, and provides a way to study the effect of the collisions and to detect entanglement. What the researchers observed was an enormous number of entangled atoms – about 100 times more than ever before observed. They also saw that the entanglement is non-local – it involves atoms that are not close to each other. Between any two entangled atoms there are thousands of other atoms, many of which are entangled with still other atoms, in a giant, hot and messy entangled state.
What they also saw, as Jia Kong, first author of the study, recalls, “is that if we stop the measurement, the entanglement remains for about 1 millisecond, which means that 1000 times per second a new batch of 15 trillion atoms is being entangled. And you must think that 1 ms is a very long time for the atoms, long enough for about fifty random collisions to occur. This clearly shows that the entanglement is not destroyed by these random events. This is maybe the most surprising result of the work”.
The observation of this hot and messy entangled state paves the way for ultra-sensitive magnetic field detection. For example, in magnetoencephalography (magnetic brain imaging), a new generation of sensors uses these same hot, high-density atomic gases to detect the magnetic fields produced by brain activity. The new results show that entanglement can improve the sensitivity of this technique, which has applications in fundamental brain science and neurosurgery.
As ICREA [Catalan Institution for Research and Advanced Studies] Prof. at ICFO Morgan Mitchell states, “this result is surprising, a real departure from what everyone expects of entanglement.” He adds “we hope that this kind of giant entangled state will lead to better sensor performance in applications ranging from brain imaging to self-driving cars to searches for dark matter
A Spin Singlet and QND
A spin singlet is one form of entanglement where the multiple particles’ spins–their intrinsic angular momentum–add up to 0, meaning the system has zero total angular momentum. In this study, the researchers applied quantum non-demolition (QND) measurement to extract the information of the spin of trillions of atoms. The technique passes laser photons with a specific energy through the gas of atoms. These photons with this precise energy do not excite the atoms but they themselves are affected by the encounter. The atoms’ spins act as magnets to rotate the polarization of the light. By measuring how much the photons’ polarization has changed after passing through the cloud, the researchers are able to determine the total spin of the gas of atoms.
The SERF regime
Current magnetometers operate in a regime that is called SERF, far away from the near absolute zero temperatures that researchers typically employ to study entangled atoms. In this regime, any atom experiences many random collisions with other neighbouring atoms, making collisions the most important effect on the state of the atom. In addition, because they are in a hot medium rather than an ultracold one, the collisions rapidly randomize the spin of the electrons in any given atom. The experiment shows, surprisingly, that this kind of disturbance does not break the entangled states, it merely passes the entanglement from one atom to another.
Originally, the plan was to produce some sort of a Canadian science culture roundup for 2019 but it came to my attention that 2019 was also an end-of-decade year (sometimes I miss the obvious). I’ll do my best to make this snappy but it is a review (more or less) of the last 10 years (roughly) and with regard to science culture in Canada, I’m giving the term a wide interpretation while avoiding (for the most part) mention of traditional science communication/outreach efforts such as university rresearch, academic publishing, academic conferences, and the like.
Since writing that opening paragraph in late December 2019, COVID-19 took over the world and this review seemed irrelevant for a while but as time passed, Iit occurred to me it might serve as a reminder of past good times and as a hope for the future.
Having started this blog in 2008, I’ve had the good fortune to observe a big increase in the number and range of science outreach/communication/culture initiatives, projects, festivals, etc. It’s tempting to describe it as an explosion of popular interest but I have no idea if this is true. I spend much of my time searching out and writing up this kind of work in addition to the emerging science and technology that I follow and my perception is most likely skewed by my pursuits. What i can say is that in 2019 there was more of everything to do with science culture/outreach/communication than there was when I started in 2008.
Coincidentally, I wrote a three-part series about science communication (including science outreach/culture projects) in Canada in Sept. 2009, just months before the start of this decade. In retrospect, the series is sprawling everywhere and it looks to me like I was desperately trying to make something look bigger than it actually was.
I’m looking at the more formal aspects of science communication and so onto mainstream media and education. This is the saddest section but don’t worry it gets better as it goes on.
As I note in the following subsection, there are fewer science writers employed by mainstream media, especially in Canada. The only science writer (that I know of) who’s currently employed by a newspaper is Ivan Semeniuk. for the Globe and Mail.
Margaret Munro who was the science writer for PostMedia (publisher of most newspaper dailies in Canada) is now a freelancer. Kate Lunau, a health and science journalist for Maclean’s Magazine (Canada) until 2016 and then Motherboard/VICE (US online publication) until March 2019 now publishes her own newsletter.
Daily Planet, which was a long running science programme (under various names since 1995) on Discovery Channel Canada and which inspired iterations in other countries, was cancelled in 2018 but there is still a Twitter feed being kept up to date and a webpage with access to archived programmes.
The Canadian Broadcasting Corporation (CBC) programmes, Spark for technology and Quirks & Quarks for science on the radio side and the Nature of Things for science, wildlife, and technology on television carry on year after year and decade after decade.
A more recent addition (2019?) to the CBC lineup is a podcast that touches on science and other topics, Tai Asks Why? According to the programme’s About page, the host (Tai Poole) is in grade seven. No podcasts dated after September 2019 have been posted on Tia’s page.
Yes Magazine for children and Seed magazine (for adults) have both died since 2009. On a happier note, Canadian children’s science magazines are easier to find these days either because I got lucky on my search and/or because there are more of them to find.
Thank you to helpwevegotkids.com for their 10 Awesome Magazines for Canadian Kids webpage. First published in 2016, it is updated from time to time, most recently in October 2019 by Heather Camlot; it’s where I found many of these science/technology magazines (Note: I’m not sure how long these magazines have been published but they are all new to me),
Chickadee Magazine: ages 6-9 ( Every month, the Chickadee team creates a package of interactive stories, puzzles, animal features, and science experiments to educate and entertain readers.) It’s from the folks at owlkids.com
OWL Magazine: ages 9-13 (… highlight the elements of science and tech, engineering, art and math ) Also from the folks at owlkids.com
AdventureBox: ages 6 – 9 (… nature with beautiful photographs and fascinating scientific information … Hilarious and adventurous comic-strips, games and quizzes … An audio CD every 2 months) Also from the folks at owlkids.com
DiscoveryBox: ages 9 – 12 ( … Animals and nature, with spectacular photographs … Fascinating scientific topics, with clear explanations and experiments to carry out …) Also from the folks at owlkids.com BTW, I was not able to find out much about the Owl Kids organization.
WILD magazine ( … jam-packed with fun wildlife stories, games and pictures for youngsters of all ages. It’s a great way to get the children in your life engaged in nature and share your passion for the outdoors. Published 6 times per year) From the folks at the Canadian Wildlife Federation (enough said).
Bazoof! (… suited for ages 7-12 … nutrition, personal care, fitness, healthy lifestyles, character development, eco-education—all in a creative and zany style! Filled with short stories, comics, recipes, puzzles, games, crafts, jokes, riddles, pet care, interviews, healthy snacks, sports, true stories, fun facts, prizes and more!) Bazoof! is being brought to you by the team responsible for Zamoof! You might want to read their About page. That’s all I can dig up.
Brainspace (an augmented reality magazine for kids 8 – 14) As best I can determine they are still ‘publishing’ their interactive magazine but they make finding information about themselves or their organization a little challenging. It’s published in Ontario and its publisher Nicky Middleton had this in her LinkedIn profile: “Publisher of Brainspace interactive magazine for kids 8-12. Creating augmented reality content for teaching resources in partnership with Brock University, District School Board of Niagara.”
One more thing regarding mainstream media
While there are fewer science journalists being employed, there’s still a need for science writing and journalism. The Science Media Centre of Canada (SMCC) opened in 2010 (from its Wikipedia entry),
… to serve journalists with accurate information on scientific matters. The centre has a Research Advisory Panel of 20 Canadian scientists who will make their expertise available in a simple and understandable manner. In order to secure objectivity, the centre has an Editorial Advisory Committee of eight journalists. The centre is bilingual.
As of January 2020, the SMCC is still in operation.
The University of British Columbia’s Journalism School (Vancouver) no longer has a Science Journalism Research Group nor does Concordia University (Montréal) have its Science Journalism Project. I have checked both journalism schools and cannot find any indication there is a science programme or specific science courses of any kind for journalists or other communicators but I didn’t spend a lot of time digging. Interestingly, the chair, David Secko, of Concordia’s journalism programme is a science journalist himself and a member of the Editorial Advisory Committee of the Science Media Centre of Canada.
The lack of science journalism programmes in Canada seems to reflect on overall lack of science journalism. It’s predictable given that the newspapers that once harboured science journalists have trimmed and continue to trim back their staffs.
Science centres, museums, and the like are considered part of the informal science community with Makerspaces being a new addition. For the most part, their target audience is children but they are increasingly (since 2010, I believe) offering events aimed at adults. The Canadian Association of Science Centres (CASC) describes itself and its membership this way (from the CASC About Us webpage),
CASC members are a diverse group of organisations that support informal learning of science, technology and nature. Our common bond is that we offer creative programming and exhibitions for visitors that inspire a drive to learn, create, and innovate.
If you are a member of a Science Centres, Museums, Aquariums, Planetariums and Makerspaces [these are a 2010s phenomenon] you could benefit from our reciprocal admission agreement. Not all CASC Members are participants in the Reciprocal Admissions Agreement. Click here for more information.
You can find a full list of their members including the Ingenium museums (the federal consortium of national Canadian science museums), the Saskatchewan Science Centre, the Nunavut Research Institute, Science East, and more, here.
I’m calling what follows ‘truly informal science culture’.
Science: the informal (sometimes cultural) scene
When I first started (this blog) there was one informal science get-together (that I knew of locally) and that was Vancouver Café Scientifque and its monthly events, which are still ongoing. You can find our more about the parent organization, which was started in Leeds, England in 1998. Other Canadian cities listed as having a Café Scientifique: Ottawa, Victoria, Mississauga, and Saskatoon.
Now onto the music, the dance, and more
Sing a song of science
Baba Brinkman is well known for his science raps. The rapper and playwright (from British Columbia) lives in New York City these days with his wife and sometime performance collaborator, neuroscientist Dr. Heather Berlin and their two children (see his Wikipedia entry for more), he is still Canadian (I think).
He got his start rapping science in 2008 when I think he was still living in Vancouver (Canada) after gaining the attention of UK professor Mark Pallen who commissioned him to write a rap about evolution. The Rap Guide to Evolution premiered at the 2009 Edinburgh Fringe Festival. Here’s a video of Brinkman’s latest science rap (Data Science) posted on YouTube on October 21, 2019,
I find this one especially interesting since Brinkman’s mother is the Honourable Joyce Murray, a member of parliament and the Minister of Digital Government in Prime Minister Justin Trudeau’s latest cabinet. (My December 27, 2019 posting highlights what I believe to be the importance of the Minister of Digital Government in the context of the government’s science and technology vision. Scroll down about 25% of the way to the subhead titled “The Minister of Digital Government and a bureaucratic débacle,”) You can find out more about Baba Brinkman here.
Tim Blais of A Capella Science first attracted my notice in 2014 thanks to David Bruggeman and his Pasco Phronesis blog (btw: David, I miss your posts about science and music which are how I found out most of what I know about the Canadian science music scene).
Blais (who has a master’s degree in physics from McGill University in Québec) started producing his musical science videos in 2012. I featured one of his earliest efforts (and one of my favourites, Rolling in the Higgs [Adele parody]) in my July 18, 2014 posting.
Dating back to 2012. The Institute of Quantum Computing at the University of Waterloo held two performances of Quantum: Music at the Frontier of Science. Raymond Laflamme, then director of the institute, wrote a September 20, 2012 article (The Quantum Symphony: A Cultural Entanglement) about the performances. You can see a video (15 mins., 45 secs.,) of the February 2012 performances here.
More recently, the Life Sciences Institute at the University of British Columbia (UBC) hosted a performance of Sounds and Science – Vienna Meets Vancouver in late 2019. I covered it in a November 12, 2019 posting (scroll down to the Sounds and Science subheading). The story about how the series, which has its home base in Vienna, started is fascinating. The sold out Vancouver performance was a combination of music and lecture featuring the Vienna Philharmonic and UBC researchers. According to this Sounds and Science UBC update,
For those who missed this exceptional evening, JoyTV and its CARPe Diem show will be producing an episode focusing on the concert, to be aired in February, 2020 [emphasis mine].
There is another way to look at musical science and that’s to consider the science of music which is what they do at the Large Interactive Virtual Environment Laboratory (LIVELab) at McMaster University (Hamilton, Ontario, Canada). it’s “a research concert hall. It functions as both a high-tech laboratory and theatre, opening up tremendous opportunities for research and investigation”, you can read more about it in my November 29, 2019 posting.
One last thing, there is data sonification which means finding a way to turn data into music or a sound which can more or less be defined as musical. There may be other data sonification projects and presentations in Canada but these are the ones I’ve tripped across (Note: Some links have bee removed),
Songs of the Ottawa From the website: “Songs of the Ottawa” is the Master’s Research Project of Cristina Wood, under the co-supervision of Dr. Joanna Dean and Dr. Shawn Graham. She completed her Master’s of Arts in Public History with a Specialization in Digital Humanities at Carleton University in spring 2019. She will continue her explorations of the Ottawa River in the Ph.D. program at York University [fall 2020]. Be in touch with Cristina on Twitter or send an email to hello [at] cristinawood [dot] ca.”
The Art of Data Sonification (This January 2019 workshop at Inter/Access in Toronto is over.) From the website: “Learn how to turn data into sound! Dan Tapper will teach participants how to apply different data sonification techniques, collect and produce a variety of sonifications, and how to creatively use these sonifications in their own work. The workshop will move from looking at data sonification through the lens of Dan Tapper’s work sonifying data sets from NASA, to collecting, cleaning and using your own data for artistic creation. Participants will work with pre-gathered and cleaned data sets before collecting and working with personal data and online data sets. Tools will be provided by Tapper created in Pure Data and Processing, as well as versions for Max/MSP users. A particular focus will be placed on how to use data sets and the created sonifications in creative practice – moving beyond quantitative sonic representations to richer material. “
Sonification: Making Data Sound (This September 2019 workshop at the Peter Wall Institute for Advanced Studies at the University of British Columbia is also over.) From the website: ” Computers and music have been mingling their intimate secrets for over 50 years. These two worlds evolve in tandem, and where they intersect they spawn practices that are entirely novel. One of these is “sonification,” turning raw data into sounds and sonic streams to discover new musical relationships within the dataset. This is similar to data visualization, a strategy that reveals new insights from data when it is made for the eye to perceive as graphs or animations. A key advantage with sonification is sound’s ability to present trends and details simultaneously at multiple time scales, allowing us to absorb and integrate information in the same way we listen to music. In this workshop, Chris Chafe will lead a discussion of the practice and application of sonification in a wide array of disciplines, drawing on his own extensive experience in this field.”
I have been looking for data sonification projects in Canada for years. It’s amazing to me that all of this sprung up in the last year of this decade. If there’s more, please do let me know in the Comments section.
Science blogging in Canada
The big news for the decade was the founding and launch of Science Borealis, a Canadian science blog aggregator in 2013. Assuming I counted right in December 2019, there are 146 blogs. These are not all independent bloggers, many institutional blogs are included. Also, I’m not sure how active some of these blogs are. Regardless, that’s a pretty stunning number especially when I consider that my annual Canadian blog roundup from 2010 -2012 would have boasted 20 – 30 Canadian science blogs at most.
I’m not sure why ASAP Science (Michael Moffit and Gregory Brown) isn’t included on Science Borealis but maybe the science vloggers (video bloggers) prefer to go it alone. or they fit into another category of online science. Regardless, ASAP Science has been around since May 2012 according to their About page. In addition to the science education/information they provide, there’s music, including this Taylor Swift Acapella Parody.
One of the earliest Canadians to create a science blog,Gregor Wolbring, Associate Professor at the University of Calgary’s Cumming School of Medicine, started his in 2006. He has taken a few breaks, 2011 and August 2013 – June 2017 but he’s back at it these days. He is in a sense a progenitor for Canadian science blogging. At one time, his blog was so popular that US researchers included it in their studies on what was then ‘the blogging phenomenon’. His focus academically and on his blog is on rehabilitation and disability. This webpage on his blog is of particular interest to me: FUTUREBODY: The Future of the Body in the Light of Neurotechnology. It’s where he lists papers from himself and his colleagues’ in the ERANET NEURON ELSI/ELSA funded by the European Community. (ELSI is Ethical, Legal and Social Implications and ELSA is Ethical, Legal, and Social Aspects.)
Canada’s Favourite Science Online, a competition co-sponsored by Science Borealia and the Science Writers and Communicators of Canada (SWCC), gives a People’s Choice Award annually in two categories: blog and science site. This September 16, 2019 posting on the Science Borealis blog features the finalists in the categories and a pretty decent sampling of what available online from the Canadian science community.
Science in the City is a Canadian life sciences blog aggregator and job and event listing website. The name is an official mark of McMaster University (Ontario, Canada) and it is used and registered by STEMCELL Technologies Canada Inc. Here’s more from their AboutScienceInTheCity webpage,
As scientists ourselves, we know that science is accelerated by collaboration and connection, but that the busy, demanding lifestyle of a scientist makes this challenging. Thus, we saw the need for a central resource that connects local scientists, provides them with a platform to share their ideas, and helps them stay current with the news, events, and jobs within their local scientific community. This inspired us to launch Science in the City in our hometown of Vancouver, Canada in 2017.
Science in the City is your complete source for all the life science news and events happening in your city. The Science in the City website and weekly newsletter provide researchers and medical professionals with breaking news, in-depth articles, and insightful commentary on what is happening around them. By supplying scientists with a resource for the local news and events that affect them, Science in the City fosters learning and collaboration within scientific communities, ultimately supporting the advancement of science and medicine.
Vancouver is our hometown, so it made sense to launch this exciting initiative in our own backyard. But we’re only getting started! We’ve launched Science in the City in Seattle and Boston, and we’re currently working on bringing Science in the City to several more scientific communities across North America and Europe!
Do check their event listings as they range past life science to many other interesting ‘sciencish’ get togethers. For example, in early 2020 (in Vancouver) there was,
At a guess their funding comes from STEMCELL Technologies while Science Borealis was originally (not sure what the status is today) bankrolled by Canadian Science Publishing (CSP).
It’s just dance, dance, dance
Ranging from pigeon courtship to superconductivity, Canadian scientists have scored a number of wins in the Dance Your Ph.D. competition founded in 2008 according to its Wikipedia entry and held by Science Magazine and the American Association for the Advancement of Science (AAAS). The contest requires that the entrant dance either as a solo artist or as part of a troupe.
In 2018, a University of Alberta student won in the physics category and then went on to win overall. I covered it in a February 22, 2019 posting. Because I love the video, here is Pramodh Senarath Yapa with his Superconductivity: The Musical!, again,
BTW, John Bohannon who came up with the idea for the contest wrote this February 15, 2019 article about Yapa’s win for Science Magazine.
While searching for other Canadian Dance Your Ph.D. winners, I found some from the 2010 and 2011 contests. (If there are others, please do let me know in the Comments section.)
McConnell’s video did not win in its division but another Canadian student, Queen’s University (Ontario) biologist, Emma Ware won the 2011 social science division for ‘A Study of Social Interactivity Using Pigeon Courtship‘. For more about McConnell and Ware’s 2011 efforts, you can read Tyler Irving’s October 20, 2011 posting on his eponymous blog. (Side note: Irving is a Canadian science writer who started the blog in 2011 and took a five year hiatus from January 2015 to January 2020.)
Lesley Telford, choreographer and director of Inverso Productions based in Vancouver, seems to have started showing a dance piece inspired by Albert Einstein’s famous description of quantum entanglement as “spooky action from s a distance” in 2017.
I first wrote about it in an April 20, 2017 posting. The title, at that time, was, ‘Three Sets/Relating At A Distance; My tongue, your ear / If / Spooky Action at a Distance (phase 1‘. In 2017, Telford was artist-in-residence at the Dance Centre and TRIUMF, Canada’s national laboratory for particle and nuclear physics and accelerator-based science, both located in Vancouver.
She has continued to work with the concept and most recently her company gave performances of ‘Spooky Action’ in 2019 and will go on tour in 2020 according to her company’s homepage.
Unlike Lesley Telford who has a single science-inspired piece, Blue Ceilingdance in Toronto, is organized around the idea of art (dance) and science according to the company’s About page,
Blue Ceiling dance aims to pierce the soul through investigations at the intersection of art and science, and physical rigour provoked by the imagination. By peering into the mysterious corners of human experience and embodying the natural laws of the universe, we want to inspire empathy and curiosity. Through creation, production, commissioning and touring of new dance and multi-disciplinary works and through the Imaginative Body Classes, Blue Ceiling dance uses the poetry of the body and of scientific language to describe our experience of the world through the lens of poetic naturalism.
Blue Ceiling dance was founded by Lucy Rupert in 2004, as an umbrella for her creative endeavours. …
Our biggest project to date premieres January 23-26th, 2020 at The Theatre Centre [Toronto].
Using the length of time it takes light to travel from the Sun to Earth, we launch into 8 overlapping meditations on the physical behaviour of light, the metaphors of astrophysics, and the soul of cosmology, as they brush against a sense of our own mortality. What would you do with your last 8 minutes and 17 seconds before the lights go out?
Choreographed and conceived by Lucy Rupert with additional choreography by Karen Kaeja, Emma Kerson and Jane Alison McKinney, and Michael Caldwell. With text written by Hume Baugh.
The company’s repertoire is diverse and focused largely on science,
Animal Vegetable Mineral is a site-specific work with a naturalist-led hike. Exploring embodiments of each category of matter, the dancers form an ecosystem under stress, and highlight the interconnectedness of all species and our deep need for one another. Audiences explore their local environment and encounter human embodiments in an intimate performance setting.
Originally made for the High Park Nature Centre in Toronto, the piece is adaptable to different ecosystems and environments.
dead reckoning Perplexing, haunting and slightly mischievous, with choreography by Lucy Rupert and international ballet choreographer Peter Quanz. The launching point for this work of dance-theatre is Sir Ernest Shackleton’s ill-fated expedition to Antarctica in 1914 and the mysterious experiences surrounding his life-or-death situation. Three linked dances offer three views of an explorer pursued by an enigmatic “other”.
Bye, bye ScienceOnline Vancouver
A ScienceOnline conference and community based in the United States inspired a short-lived but exciting offshoot in Vancouver. With much ado, their first event was held on April 19, 2012. As I recall, by December 2012, it had died.
The volunteers were wildly ambitious and it’s very hard to maintain the level of dynamism and technology they established on their first night. Here’s how I described the first event in my April 20, 2012 posting, ” It was a very technology-heavy event in that there was livestreaming, multiple computers and screens, references to tweeting and Storify, etc.” That’s a lot to do on a regular basis as volunteers. By Christmas 2012, ScienceOnline was gone. It was a great and I’m thankful for it.
Now onto part 2 where you’ll find the visual arts, poetry, festivals, and more.
This supremacy, refers to an engineering milestone and a October 23, 2019 news item on ScienceDaily announces the milestone has been reached,
Researchers in UC [University of California] Santa Barbara/Google scientist John Martinis’ group have made good on their claim to quantum supremacy. Using 53 entangled quantum bits (“qubits”), their Sycamore computer has taken on — and solved — a problem considered intractable for classical computers.
“A computation that would take 10,000 years on a classical supercomputer took 200 seconds on our quantum computer,” said Brooks Foxen, a graduate student researcher in the Martinis Group. “It is likely that the classical simulation time, currently estimated at 10,000 years, will be reduced by improved classical hardware and algorithms, but, since we are currently 1.5 trillion times faster, we feel comfortable laying claim to this achievement.”
The feat is outlined in a paper in the journal Nature.
The milestone comes after roughly two decades of quantum computing research conducted by Martinis and his group, from the development of a single superconducting qubit to systems including architectures of 72 and, with Sycamore, 54 qubits (one didn’t perform) that take advantage of the both awe-inspiring and bizarre properties of quantum mechanics.
“The algorithm was chosen to emphasize the strengths of the quantum computer by leveraging the natural dynamics of the device,” said Ben Chiaro, another graduate student researcher in the Martinis Group. That is, the researchers wanted to test the computer’s ability to hold and rapidly manipulate a vast amount of complex, unstructured data.
“We basically wanted to produce an entangled state involving all of our qubits as quickly as we can,” Foxen said, “and so we settled on a sequence of operations that produced a complicated superposition state that, when measured, returns bitstring with a probability determined by the specific sequence of operations used to prepare that particular superposition. The exercise, which was to verify that the circuit’s output correspond to the equence used to prepare the state, sampled the quantum circuit a million times in just a few minutes, exploring all possibilities — before the system could lose its quantum coherence.
‘A complex superposition state’
“We performed a fixed set of operations that entangles 53 qubits into a complex superposition state,” Chiaro explained. “This superposition state encodes the probability distribution. For the quantum computer, preparing this superposition state is accomplished by applying a sequence of tens of control pulses to each qubit in a matter of microseconds. We can prepare and then sample from this distribution by measuring the qubits a million times in 200 seconds.”
“For classical computers, it is much more difficult to compute the outcome of these operations because it requires computing the probability of being in any one of the 2^53 possible states, where the 53 comes from the number of qubits — the exponential scaling is why people are interested in quantum computing to begin with,” Foxen said. “This is done by matrix multiplication, which is expensive for classical computers as the matrices become large.”
According to the new paper, the researchers used a method called cross-entropy benchmarking to compare the quantum circuit’s output (a “bitstring”) to its “corresponding ideal probability computed via simulation on a classical computer” to ascertain that the quantum computer was working correctly.
“We made a lot of design choices in the development of our processor that are really advantageous,” said Chiaro. Among these advantages, he said, are the ability to experimentally tune the parameters of the individual qubits as well as their interactions.
While the experiment was chosen as a proof-of-concept for the computer, the research has resulted in a very real and valuable tool: a certified random number generator. Useful in a variety of fields, random numbers can ensure that encrypted keys can’t be guessed, or that a sample from a larger population is truly representative, leading to optimal solutions for complex problems and more robust machine learning applications. The speed with which the quantum circuit can produce its randomized bit string is so great that there is no time to analyze and “cheat” the system.
“Quantum mechanical states do things that go beyond our day-to-day experience and so have the potential to provide capabilities and application that would otherwise be unattainable,” commented Joe Incandela, UC Santa Barbara’s vice chancellor for research. “The team has demonstrated the ability to reliably create and repeatedly sample complicated quantum states involving 53 entangled elements to carry out an exercise that would take millennia to do with a classical supercomputer. This is a major accomplishment. We are at the threshold of a new era of knowledge acquisition.”
With an achievement like “quantum supremacy,” it’s tempting to think that the UC Santa Barbara/Google researchers will plant their flag and rest easy. But for Foxen, Chiaro, Martinis and the rest of the UCSB/Google AI Quantum group, this is just the beginning.
“It’s kind of a continuous improvement mindset,” Foxen said. “There are always projects in the works.” In the near term, further improvements to these “noisy” qubits may enable the simulation of interesting phenomena in quantum mechanics, such as thermalization, or the vast amount of possibility in the realms of materials and chemistry.
In the long term, however, the scientists are always looking to improve coherence times, or, at the other end, to detect and fix errors, which would take many additional qubits per qubit being checked. These efforts have been running parallel to the design and build of the quantum computer itself, and ensure the researchers have a lot of work before hitting their next milestone.
“It’s been an honor and a pleasure to be associated with this team,” Chiaro said. “It’s a great collection of strong technical contributors with great leadership and the whole team really synergizes well.”
Here’s a link to and a citation for the paper,
Quantum supremacy using a programmable superconducting processor by Frank Arute, Kunal Arya, Ryan Babbush, Dave Bacon, Joseph C. Bardin, Rami Barends, Rupak Biswas, Sergio Boixo, Fernando G. S. L. Brandao, David A. Buell, Brian Burkett, Yu Chen, Zijun Chen, Ben Chiaro, Roberto Collins, William Courtney, Andrew Dunsworth, Edward Farhi, Brooks Foxen, Austin Fowler, Craig Gidney, Marissa Giustina, Rob Graff, Keith Guerin, Steve Habegger, Matthew P. Harrigan, Michael J. Hartmann, Alan Ho, Markus Hoffmann, Trent Huang, Travis S. Humble, Sergei V. Isakov, Evan Jeffrey, Zhang Jiang, Dvir Kafri, Kostyantyn Kechedzhi, Julian Kelly, Paul V. Klimov, Sergey Knysh, Alexander Korotkov, Fedor Kostritsa, David Landhuis, Mike Lindmark, Erik Lucero, Dmitry Lyakh, Salvatore Mandrà, Jarrod R. McClean, Matthew McEwen, Anthony Megrant, Xiao Mi, Kristel Michielsen, Masoud Mohseni, Josh Mutus, Ofer Naaman, Matthew Neeley, Charles Neill, Murphy Yuezhen Niu, Eric Ostby, Andre Petukhov, John C. Platt, Chris Quintana, Eleanor G. Rieffel, Pedram Roushan, Nicholas C. Rubin, Daniel Sank, Kevin J. Satzinger, Vadim Smelyanskiy, Kevin J. Sung, Matthew D. Trevithick, Amit Vainsencher, Benjamin Villalonga, Theodore White, Z. Jamie Yao, Ping Yeh, Adam Zalcman, Hartmut Neven & John M. Martinis. Nature volume 574, pages505–510 (2019) DOI: https://doi.org/10.1038/s41586-019-1666-5 Issue Date 24 October 2019
Weaving a quantum processor from light is a jaw-dropping event (as far as I’m concerned). An October 17, 2019 news item on phys.org makes the announcement,
An international team of scientists from Australia, Japan and the United States has produced a prototype of a large-scale quantum processor made of laser light.
Based on a design ten years in the making, the processor has built-in scalability that allows the number of quantum components—made out of light—to scale to extreme numbers. The research was published in Science today [October 18, 2019; Note: I cannot explain the discrepancy between the dates]].
Quantum computers promise fast solutions to hard problems, but to do this they require a large number of quantum components and must be relatively error free. Current quantum processors are still small and prone to errors. This new design provides an alternative solution, using light, to reach the scale required to eventually outperform classical computers on important problems.
“While today’s quantum processors are impressive, it isn’t clear if the current designs can be scaled up to extremely large sizes,” notes Dr Nicolas Menicucci, Chief Investigator at the Centre for Quantum Computation and Communication Technology (CQC2T) at RMIT University in Melbourne, Australia.
“Our approach starts with extreme scalability – built in from the very beginning – because the processor, called a cluster state, is made out of light.”
Using light as a quantum processor
A cluster state is a large collection of entangled quantum components that performs quantum computations when measured in a particular way.
“To be useful for real-world problems, a cluster state must be both large enough and have the right entanglement structure. In the two decades since they were proposed, all previous demonstrations of cluster states have failed on one or both of these counts,” says Dr Menicucci. “Ours is the first ever to succeed at both.”
To make the cluster state, specially designed crystals convert ordinary laser light into a type of quantum light called squeezed light, which is then weaved into a cluster state by a network of mirrors, beamsplitters and optical fibres.
The team’s design allows for a relatively small experiment to generate an immense two-dimensional cluster state with scalability built in. Although the levels of squeezing – a measure of quality – are currently too low for solving practical problems, the design is compatible with approaches to achieve state-of-the-art squeezing levels.
The team says their achievement opens up new possibilities for quantum computing with light.
“In this work, for the first time in any system, we have made a large-scale cluster state whose structure enables universal quantum computation.” Says Dr Hidehiro Yonezawa, Chief Investigator, CQC2T at UNSW Canberra. “Our experiment demonstrates that this design is feasible – and scalable.”
The experiment was an international effort, with the design developed through collaboration by Dr Menicucci at RMIT, Dr Rafael Alexander from the University of New Mexico and UNSW Canberra researchers Dr Hidehiro Yonezawa and Dr Shota Yokoyama. A team of experimentalists at the University of Tokyo, led by Professor Akira Furusawa, performed the ground-breaking experiment.
Here’s a link to and a citation for the paper,
Generation of time-domain-multiplexed two-dimensional cluster state by Warit Asavanant, Yu Shiozawa, Shota Yokoyama, Baramee Charoensombutamon, Hiroki Emura, Rafael N. Alexander, Shuntaro Takeda, Jun-ichi Yoshikawa, Nicolas C. Menicucci, Hidehiro Yonezawa, Akira Furusawa. Science 18 Oct 2019: Vol. 366, Issue 6463, pp. 373-376 DOI: 10.1126/science.aay2645
An August 29, 2019 news item on phys.org broke the news about breaking a record for transferring quantum entanglement between matter and light ,
The quantum internet promises absolutely tap-proof communication and powerful distributed sensor networks for new science and technology. However, because quantum information cannot be copied, it is not possible to send this information over a classical network. Quantum information must be transmitted by quantum particles, and special interfaces are required for this. The Innsbruck-based experimental physicist Ben Lanyon, who was awarded the Austrian START Prize in 2015 for his research, is investigating these important intersections of a future quantum Internet.
Now his team at the Department of Experimental Physics at the University of Innsbruck and at the Institute of Quantum Optics and Quantum Information of the Austrian Academy of Sciences has achieved a record for the transfer of quantum entanglement between matter and light. For the first time, a distance of 50 kilometers was covered using fiber optic cables. “This is two orders of magnitude further than was previously possible and is a practical distance to start building inter-city quantum networks,” says Ben Lanyon.
Lanyon’s team started the experiment with a calcium atom trapped in an ion trap. Using laser beams, the researchers write a quantum state onto the ion and simultaneously excite it to emit a photon in which quantum information is stored. As a result, the quantum states of the atom and the light particle are entangled. But the challenge is to transmit the photon over fiber optic cables. “The photon emitted by the calcium ion has a wavelength of 854 nanometers and is quickly absorbed by the optical fiber”, says Ben Lanyon. His team therefore initially sends the light particle through a nonlinear crystal illuminated by a strong laser. Thereby the photon wavelength is converted to the optimal value for long-distance travel: the current telecommunications standard wavelength of 1550 nanometers. The researchers from Innsbruck then send this photon through a 50-kilometer-long optical fiber line. Their measurements show that atom and light particle are still entangled even after the wavelength conversion and this long journey.
Even greater distances in sight
As a next step, Lanyon and his team show that their methods would enable entanglement to be generated between ions 100 kilometers apart and more. Two nodes send each an entangled photon over a distance of 50 kilometers to an intersection where the light particles are measured in such a way that they lose their entanglement with the ions, which in turn would entangle them. With 100-kilometer node spacing now a possibility, one could therefore envisage building the world’s first intercity light-matter quantum network in the coming years: only a handful of trapped ion-systems would be required on the way to establish a quantum internet between Innsbruck and Vienna, for example.
Lanyon’s team is part of the Quantum Internet Alliance, an international project within the Quantum Flagship framework of the European Union. The current results have been published in the Nature journal Quantum Information. Financially supported was the research among others by the Austrian Science Fund FWF and the European Union.
Here’s a link to and a citation for the paper,
Light-matter entanglement over 50 km of optical fibre by V. Krutyanskiy, M. Meraner, J. Schupp, V. Krcmarsky, H. Hainzer & B. P. Lanyon. npj Quantum Information volume 5, Article number: 72 (2019) DOI: https://doi.org/10.1038/s41534-019-0186-3 Published: 27 August 2019
It seems sound is becoming more prominent as a means of science data communication (data sonification) and in this upcoming case, data transfer. From a June 5, 2018 news item on ScienceDaily,
Quantum physics is on the brink of a technological breakthrough: new types of sensors, secure data transmission methods and maybe even computers could be made possible thanks to quantum technologies. However, the main obstacle here is finding the right way to couple and precisely control a sufficient number of quantum systems (for example, individual atoms).
A team of researchers from TU Wien and Harvard University has found a new way to transfer the necessary quantum information. They propose using tiny mechanical vibrations. The atoms are coupled with each other by ‘phonons’ — the smallest quantum mechanical units of vibrations or sound waves.
“We are testing tiny diamonds with built-in silicon atoms – these quantum systems are particularly promising,” says Professor Peter Rabl from TU Wien. “Normally, diamonds are made exclusively of carbon, but adding silicon atoms in certain places creates defects in the crystal lattice where quantum information can be stored.” These microscopic flaws in the crystal lattice can be used like a tiny switch that can be switched between a state of higher energy and a state of lower energy using microwaves.
Together with a team from Harvard University, Peter Rabl’s research group has developed a new idea to achieve the targeted coupling of these quantum memories within the diamond. One by one they can be built into a tiny diamond rod measuring only a few micrometres in length, like individual pearls on a necklace. Just like a tuning fork, this rod can then be made to vibrate – however, these vibrations are so small that they can only be described using quantum theory. It is through these vibrations that the silicon atoms can form a quantum-mechanical link to each other.
“Light is made from photons, the quantum of light. In the same way, mechanical vibrations or sound waves can also be described in a quantum-mechanical manner. They are comprised of phonons – the smallest possible units of mechanical vibration,” explains Peter Rabl. As the research team has now been able to show using simulation calculations, any number of these quantum memories can be linked together in the diamond rod thanks to these phonons. The individual silicon atoms are “switched on and off” using microwaves. During this process, they emit or absorb phonons. This creates a quantum entanglement of different silicon defects, thus allowing quantum information to be transferred.
The road to a scalable quantum network
Until now it was not clear whether something like this was even possible: “Usually you would expect the phonons to be absorbed somewhere, or to come into contact with the environment and thus lose their quantum mechanical properties,” says Peter Rabl. “Phonons are the enemy of quantum information, so to speak. But with our calculations, we were able to show that, when controlled appropriately using microwaves, the phonons are in fact useable for technical applications.”
The main advantage of this new technology lies in its scalability: “There are many ideas for quantum systems that, in principle, can be used for technological applications. The biggest problem is that it is very difficult to connect enough of them to be able to carry out complicated computing operations,” says Peter Rabl. The new strategy of using phonons for this purpose could pave the way to a scalable quantum technology.
Perhaps the strangest prediction of quantum theory is entanglement, a phenomenon whereby two distant objects become intertwined in a manner that defies both classical physics and a common-sense understanding of reality. In 1935, Albert Einstein expressed his concern over this concept, referring to it as “spooky action at a distance.”
Today, entanglement is considered a cornerstone of quantum mechanics, and it is the key resource for a host of potentially transformative quantum technologies. Entanglement is, however, extremely fragile, and it has previously been observed only in microscopic systems such as light or atoms, and recently in superconducting electric circuits.
In work recently published in Nature, a team led by Prof. Mika Sillanpää at Aalto University in Finland has shown that entanglement of massive objects can be generated and detected.
The researchers managed to bring the motions of two individual vibrating drumheads—fabricated from metallic aluminium on a silicon chip—into an entangled quantum state. The macroscopic objects in the experiment are truly massive compared to the atomic scale—the circular drumheads have a diametre similar to the width of a thin human hair.
‘The vibrating bodies are made to interact via a superconducting microwave circuit. The electromagnetic fields in the circuit carry away any thermal disturbances, leaving behind only the quantum mechanical vibrations’, says Professor Sillanpää, describing the experimental setup.
Eliminating all forms of external noise is crucial for the experiments, which is why they have to be conducted at extremely low temperatures near absolute zero, at –273 °C. Remarkably, the experimental approach allows the unusual state of entanglement to persist for long periods of time, in this case up to half an hour. In comparison, measurements on elementary particles have witnessed entanglement to last only tiny fractions of a second.
‘These measurements are challenging but extremely fascinating. In the future, we will attempt to teleport the mechanical vibrations. In quantum teleportation, properties of physical bodies can be transmitted across arbitrary distances using the channel of “spooky action at a distance”. We are still pretty far from Star Trek, though,’ says Dr. Caspar Ockeloen-Korppi, the lead author on the work, who also performed the measurements.
The results demonstrate that it is now possible to have control over the most delicate properties of objects whose size approaches the scale of our daily lives. The achievement opens doors for new kinds of quantum technologies, where the entangled drumheads could be used as routers or sensors. The finding also enables new studies of fundamental physics in, for example, the poorly understood interplay of gravity and quantum mechanics.
The team also included scientists from the University of New South Wales in Australia, the University of Chicago in the USA, and the University of Jyväskylä in Finland, whose theoretical innovations paved the way for the laboratory experiment.
An illustration has been made available,
An illustration of the 15-micrometre-wide drumheads prepared on silicon chips used in the experiment. The drumheads vibrate at a high ultrasound frequency, and the peculiar quantum state predicted by Einstein was created from the vibrations. Image: Aalto University / Petja Hyttinen & Olli Hanhirova, ARKH Architects.
I think it was about five years ago thatI wrote a paper on something I called ‘cognitive entanglement’ (mentioned in my July 20,2012 posting) so the latest from Northwestern University (Chicago, Illinois, US) reignited my interest in entanglement. A December 5, 2017 news item on ScienceDaily describes the latest ‘entanglement’ research,
Nearly 75 years ago, Nobel Prize-winning physicist Erwin Schrödinger wondered if the mysterious world of quantum mechanics played a role in biology. A recent finding by Northwestern University’s Prem Kumar adds further evidence that the answer might be yes.
Kumar and his team have, for the first time, created quantum entanglement from a biological system. This finding could advance scientists’ fundamental understanding of biology and potentially open doors to exploit biological tools to enable new functions by harnessing quantum mechanics.
“Can we apply quantum tools to learn about biology?” said Kumar, professor of electrical engineering and computer science in Northwestern’s McCormick School of Engineering and of physics and astronomy in the Weinberg College of Arts and Sciences. “People have asked this question for many, many years — dating back to the dawn of quantum mechanics. The reason we are interested in these new quantum states is because they allow applications that are otherwise impossible.”
Partially supported by the [US] Defense Advanced Research Projects Agency [DARPA], the research was published Dec. 5  in Nature Communications.
Quantum entanglement is one of quantum mechanics’ most mystifying phenomena. When two particles — such as atoms, photons, or electrons — are entangled, they experience an inexplicable link that is maintained even if the particles are on opposite sides of the universe. While entangled, the particles’ behavior is tied one another. If one particle is found spinning in one direction, for example, then the other particle instantaneously changes its spin in a corresponding manner dictated by the entanglement. Researchers, including Kumar, have been interested in harnessing quantum entanglement for several applications, including quantum communications. Because the particles can communicate without wires or cables, they could be used to send secure messages or help build an extremely fast “quantum Internet.”
“Researchers have been trying to entangle a larger and larger set of atoms or photons to develop substrates on which to design and build a quantum machine,” Kumar said. “My laboratory is asking if we can build these machines on a biological substrate.”
In the study, Kumar’s team used green fluorescent proteins, which are responsible for bioluminescence and commonly used in biomedical research. The team attempted to entangle the photons generated from the fluorescing molecules within the algae’s barrel-shaped protein structure by exposing them to spontaneous four-wave mixing, a process in which multiple wavelengths interact with one another to produce new wavelengths.
Through a series of these experiments, Kumar and his team successfully demonstrated a type of entanglement, called polarization entanglement, between photon pairs. The same feature used to make glasses for viewing 3D movies, polarization is the orientation of oscillations in light waves. A wave can oscillate vertically, horizontally, or at different angles. In Kumar’s entangled pairs, the photons’ polarizations are entangled, meaning that the oscillation directions of light waves are linked. Kumar also noticed that the barrel-shaped structure surrounding the fluorescing molecules protected the entanglement from being disrupted.
“When I measured the vertical polarization of one particle, we knew it would be the same in the other,” he said. “If we measured the horizontal polarization of one particle, we could predict the horizontal polarization in the other particle. We created an entangled state that correlated in all possibilities simultaneously.”
Now that they have demonstrated that it’s possible to create quantum entanglement from biological particles, next Kumar and his team plan to make a biological substrate of entangled particles, which could be used to build a quantum machine. Then, they will seek to understand if a biological substrate works more efficiently than a synthetic one.
Here’s an image accompanying the news release,
Featured in the cuvette on the left, green fluorescent proteins responsible for bioluninescence in jellyfish. Courtesy: Northwestern University
As malicious hackers find ever more sophisticated ways to launch attacks, China is about to launch the Jinan Project, the world’s first unhackable computer network, and a major milestone in the development of quantum technology.
Named after the eastern Chinese city where the technology was developed, the network is planned to be fully operational by the end of August 2017. Jinan is the hub of the Beijing-Shanghai quantum network due to its strategic location between the two principal Chinese metropolises.
“We plan to use the network for national defence, finance and other fields, and hope to spread it out as a pilot that if successful can be used across China and the whole world,” commented Zhou Fei, assistant director of the Jinan Institute of Quantum Technology, who was speaking to Britain’s Financial Times.
By launching the network, China will become the first country worldwide to implement quantum technology for a real life, commercial end. It also highlights that China is a key global player in the rush to develop technologies based on quantum principles, with the EU and the United States also vying for world leadership in the field.
The network, known as a Quantum Key Distribution (QKD) network, is more secure than widely used electronic communication equivalents. Unlike a conventional telephone or internet cable, which can be tapped without the sender or recipient being aware, a QKD network alerts both users to any tampering with the system as soon as it occurs. This is because tampering immediately alters the information being relayed, with the disturbance being instantly recognisable. Once fully implemented, it will make it almost impossible for other governments to listen in on Chinese communications.
In the Jinan network, some 200 users from China’s military, government, finance and electricity sectors will be able to send messages safe in the knowledge that only they are reading them. It will be the world’s longest land-based quantum communications network, stretching over 2 000 km.
Also speaking to the ‘Financial Times’, quantum physicist Tim Byrnes, based at New York University’s (NYU) Shanghai campus commented: ‘China has achieved staggering things with quantum research… It’s amazing how quickly China has gotten on with quantum research projects that would be too expensive to do elsewhere… quantum communication has been taken up by the commercial sector much more in China compared to other countries, which means it is likely to pull ahead of Europe and US in the field of quantum communication.’
However, Europe is also determined to also be at the forefront of the ‘quantum revolution’ which promises to be one of the major defining technological phenomena of the twenty-first century. The EU has invested EUR 550 million into quantum technologies and has provided policy support to researchers through the 2016 Quantum Manifesto.
Moreover, with China’s latest achievement (and a previous one already notched up from July 2017 when its quantum satellite – the world’s first – sent a message to Earth on a quantum communication channel), it looks like the race to be crowned the world’s foremost quantum power is well and truly underway…
Quantum entanglement—physics at its strangest—has moved out of this world and into space. In a study that shows China’s growing mastery of both the quantum world and space science, a team of physicists reports that it sent eerily intertwined quantum particles from a satellite to ground stations separated by 1200 kilometers, smashing the previous world record. The result is a stepping stone to ultrasecure communication networks and, eventually, a space-based quantum internet.
“It’s a huge, major achievement,” says Thomas Jennewein, a physicist at the University of Waterloo in Canada. “They started with this bold idea and managed to do it.”
Entanglement involves putting objects in the peculiar limbo of quantum superposition, in which an object’s quantum properties occupy multiple states at once: like Schrödinger’s cat, dead and alive at the same time. Then those quantum states are shared among multiple objects. Physicists have entangled particles such as electrons and photons, as well as larger objects such as superconducting electric circuits.
Theoretically, even if entangled objects are separated, their precarious quantum states should remain linked until one of them is measured or disturbed. That measurement instantly determines the state of the other object, no matter how far away. The idea is so counterintuitive that Albert Einstein mocked it as “spooky action at a distance.”
Starting in the 1970s, however, physicists began testing the effect over increasing distances. In 2015, the most sophisticated of these tests, which involved measuring entangled electrons 1.3 kilometers apart, showed once again that spooky action is real.
Beyond the fundamental result, such experiments also point to the possibility of hack-proof communications. Long strings of entangled photons, shared between distant locations, can be “quantum keys” that secure communications. Anyone trying to eavesdrop on a quantum-encrypted message would disrupt the shared key, alerting everyone to a compromised channel.
But entangled photons degrade rapidly as they pass through the air or optical fibers. So far, the farthest anyone has sent a quantum key is a few hundred kilometers. “Quantum repeaters” that rebroadcast quantum information could extend a network’s reach, but they aren’t yet mature. Many physicists have dreamed instead of using satellites to send quantum information through the near-vacuum of space. “Once you have satellites distributing your quantum signals throughout the globe, you’ve done it,” says Verónica Fernández Mármol, a physicist at the Spanish National Research Council in Madrid. …
Popkin goes on to detail the process for making the discovery in easily accessible (for the most part) writing and in a video and a graphic.
Russell Brandom writing for The Verge in a June 15, 2017 article about the Chinese quantum satellite adds detail about previous work and teams in other countries also working on the challenge (Note: Links have been removed),
Quantum networking has already shown promise in terrestrial fiber networks, where specialized routing equipment can perform the same trick over conventional fiber-optic cable. The first such network was a DARPA-funded connection established in 2003 between Harvard, Boston University, and a private lab. In the years since, a number of companies have tried to build more ambitious connections. The Swiss company ID Quantique has mapped out a quantum network that would connect many of North America’s largest data centers; in China, a separate team is working on a 2,000-kilometer quantum link between Beijing and Shanghai, which would rely on fiber to span an even greater distance than the satellite link. Still, the nature of fiber places strict limits on how far a single photon can travel.
According to ID Quantique, a reliable satellite link could connect the existing fiber networks into a single globe-spanning quantum network. “This proves the feasibility of quantum communications from space,” ID Quantique CEO Gregoire Ribordy tells The Verge. “The vision is that you have regional quantum key distribution networks over fiber, which can connect to each other through the satellite link.”
China isn’t the only country working on bringing quantum networks to space. A collaboration between the UK’s University of Strathclyde and the National University of Singapore is hoping to produce the same entanglement in cheap, readymade satellites called Cubesats. A Canadian team is also developing a method of producing entangled photons on the ground before sending them into space.
I wonder if there’s going to be an invitational event for scientists around the world to celebrate the launch.
I have two brain news bits, one about neural networks and quantum entanglement and another about how the brain operates on more than three dimensions.
Quantum entanglement and neural networks
A June 13, 2017 news item on phys.org describes how machine learning can be used to solve problems in physics (Note: Links have been removed),
Machine learning, the field that’s driving a revolution in artificial intelligence, has cemented its role in modern technology. Its tools and techniques have led to rapid improvements in everything from self-driving cars and speech recognition to the digital mastery of an ancient board game.
Now, physicists are beginning to use machine learning tools to tackle a different kind of problem, one at the heart of quantum physics. In a paper published recently in Physical Review X, researchers from JQI [Joint Quantum Institute] and the Condensed Matter Theory Center (CMTC) at the University of Maryland showed that certain neural networks—abstract webs that pass information from node to node like neurons in the brain—can succinctly describe wide swathes of quantum systems.
An artist’s rendering of a neural network with two layers. At the top is a real quantum system, like atoms in an optical lattice. Below is a network of hidden neurons that capture their interactions (Credit: E. Edwards/JQI)
Dongling Deng, a JQI Postdoctoral Fellow who is a member of CMTC and the paper’s first author, says that researchers who use computers to study quantum systems might benefit from the simple descriptions that neural networks provide. “If we want to numerically tackle some quantum problem,” Deng says, “we first need to find an efficient representation.”
On paper and, more importantly, on computers, physicists have many ways of representing quantum systems. Typically these representations comprise lists of numbers describing the likelihood that a system will be found in different quantum states. But it becomes difficult to extract properties or predictions from a digital description as the number of quantum particles grows, and the prevailing wisdom has been that entanglement—an exotic quantum connection between particles—plays a key role in thwarting simple representations.
The neural networks used by Deng and his collaborators—CMTC Director and JQI Fellow Sankar Das Sarma and Fudan University physicist and former JQI Postdoctoral Fellow Xiaopeng Li—can efficiently represent quantum systems that harbor lots of entanglement, a surprising improvement over prior methods.
What’s more, the new results go beyond mere representation. “This research is unique in that it does not just provide an efficient representation of highly entangled quantum states,” Das Sarma says. “It is a new way of solving intractable, interacting quantum many-body problems that uses machine learning tools to find exact solutions.”
The result was a more complete account of the capabilities of certain neural networks to represent quantum states. In particular, the team studied neural networks that use two distinct groups of neurons. The first group, called the visible neurons, represents real quantum particles, like atoms in an optical lattice or ions in a chain. To account for interactions between particles, the researchers employed a second group of neurons—the hidden neurons—which link up with visible neurons. These links capture the physical interactions between real particles, and as long as the number of connections stays relatively small, the neural network description remains simple.
Specifying a number for each connection and mathematically forgetting the hidden neurons can produce a compact representation of many interesting quantum states, including states with topological characteristics and some with surprising amounts of entanglement.
Beyond its potential as a tool in numerical simulations, the new framework allowed Deng and collaborators to prove some mathematical facts about the families of quantum states represented by neural networks. For instance, neural networks with only short-range interactions—those in which each hidden neuron is only connected to a small cluster of visible neurons—have a strict limit on their total entanglement. This technical result, known as an area law, is a research pursuit of many condensed matter physicists.
These neural networks can’t capture everything, though. “They are a very restricted regime,” Deng says, adding that they don’t offer an efficient universal representation. If they did, they could be used to simulate a quantum computer with an ordinary computer, something physicists and computer scientists think is very unlikely. Still, the collection of states that they do represent efficiently, and the overlap of that collection with other representation methods, is an open problem that Deng says is ripe for further exploration.
Blue Brain is a Swiss government brain research initiative which officially came to life in 2006 although the initial agreement between the École Politechnique Fédérale de Lausanne (EPFL) and IBM was signed in 2005 (according to the project’s Timeline page). Moving on, the project’s latest research reveals something astounding (from a June 12, 2017 Frontiers Publishing press release on EurekAlert),
For most people, it is a stretch of the imagination to understand the world in four dimensions but a new study has discovered structures in the brain with up to eleven dimensions – ground-breaking work that is beginning to reveal the brain’s deepest architectural secrets.
Using algebraic topology in a way that it has never been used before in neuroscience, a team from the Blue Brain Project has uncovered a universe of multi-dimensional geometrical structures and spaces within the networks of the brain.
The research, published today in Frontiers in Computational Neuroscience, shows that these structures arise when a group of neurons forms a clique: each neuron connects to every other neuron in the group in a very specific way that generates a precise geometric object. The more neurons there are in a clique, the higher the dimension of the geometric object.
“We found a world that we had never imagined,” says neuroscientist Henry Markram, director of Blue Brain Project and professor at the EPFL in Lausanne, Switzerland, “there are tens of millions of these objects even in a small speck of the brain, up through seven dimensions. In some networks, we even found structures with up to eleven dimensions.”
Markram suggests this may explain why it has been so hard to understand the brain. “The mathematics usually applied to study networks cannot detect the high-dimensional structures and spaces that we now see clearly.”
If 4D worlds stretch our imagination, worlds with 5, 6 or more dimensions are too complex for most of us to comprehend. This is where algebraic topology comes in: a branch of mathematics that can describe systems with any number of dimensions. The mathematicians who brought algebraic topology to the study of brain networks in the Blue Brain Project were Kathryn Hess from EPFL and Ran Levi from Aberdeen University.
“Algebraic topology is like a telescope and microscope at the same time. It can zoom into networks to find hidden structures – the trees in the forest – and see the empty spaces – the clearings – all at the same time,” explains Hess.
In 2015, Blue Brain published the first digital copy of a piece of the neocortex – the most evolved part of the brain and the seat of our sensations, actions, and consciousness. In this latest research, using algebraic topology, multiple tests were performed on the virtual brain tissue to show that the multi-dimensional brain structures discovered could never be produced by chance. Experiments were then performed on real brain tissue in the Blue Brain’s wet lab in Lausanne confirming that the earlier discoveries in the virtual tissue are biologically relevant and also suggesting that the brain constantly rewires during development to build a network with as many high-dimensional structures as possible.
When the researchers presented the virtual brain tissue with a stimulus, cliques of progressively higher dimensions assembled momentarily to enclose high-dimensional holes, that the researchers refer to as cavities. “The appearance of high-dimensional cavities when the brain is processing information means that the neurons in the network react to stimuli in an extremely organized manner,” says Levi. “It is as if the brain reacts to a stimulus by building then razing a tower of multi-dimensional blocks, starting with rods (1D), then planks (2D), then cubes (3D), and then more complex geometries with 4D, 5D, etc. The progression of activity through the brain resembles a multi-dimensional sandcastle that materializes out of the sand and then disintegrates.”
The big question these researchers are asking now is whether the intricacy of tasks we can perform depends on the complexity of the multi-dimensional “sandcastles” the brain can build. Neuroscience has also been struggling to find where the brain stores its memories. “They may be ‘hiding’ in high-dimensional cavities,” Markram speculates.
About Blue Brain
The aim of the Blue Brain Project, a Swiss brain initiative founded and directed by Professor Henry Markram, is to build accurate, biologically detailed digital reconstructions and simulations of the rodent brain, and ultimately, the human brain. The supercomputer-based reconstructions and simulations built by Blue Brain offer a radically new approach for understanding the multilevel structure and function of the brain. http://bluebrain.epfl.ch
Frontiers is a leading community-driven open-access publisher. By taking publishing entirely online, we drive innovation with new technologies to make peer review more efficient and transparent. We provide impact metrics for articles and researchers, and merge open access publishing with a research network platform – Loop – to catalyse research dissemination, and popularize research to the public, including children. Our goal is to increase the reach and impact of research articles and their authors. Frontiers has received the ALPSP Gold Award for Innovation in Publishing in 2014. http://www.frontiersin.org.