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Friday, June 3, 2011

  • Johnston here for research park naming
  • New look at the ‘double-slit experiment’
  • Editor:
  • Chris Redmond
  • Communications and Public Affairs

[Van Cappellen]

Philippe Van Cappellen joined the department of earth and environmental sciences on June 1, becoming Waterloo’s second Canada Excellence Research Chair. Quantum scientist David Cory, who began his appointment last year, was the first; both CERCs were announced in May 2010. There are just 19 CERCs across Canada, each funded by the federal government at up to $10 million over seven years. At Waterloo, Van Cappellen will seek to increase understanding of how groundwater and surface waters interact, and how they affect the health of human populations and aquatic ecosystems. His research focuses on the movement of nutrient elements and toxic metals between groundwater and surface water. “The most beneficial outcome is that we will have a much better characterization of how humans impact water quality and quantity,” he says.

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Johnston here for research park naming

David Johnston, president emeritus of the University of Waterloo and now Governor General of Canada, will be in town Sunday for two big events, including the official renaming of the university's north campus research and technology park. [Research park sign]The Governor General will unveil the sign (right) that's actually been in place since March at the entrance of the David Johnston Research and Technology Park just north of Columbia Street.

The unveiling ceremony — by invitation only — is to be held Sunday at 11:30 a.m. During proceedings hosted by Johnston's successor as president, Feridun Hamdullahpur, the Governor General "will deliver remarks about the importance of fostering research and innovation across the country, as well as the significance of bringing together government, industry and educational institutions to facilitate research and commercialization," a news release says.

It continues: "The renaming of the park is meant to recognize His Excellency’s contribution to the University of Waterloo during his 11-year tenure as president, as well as his commitment to advancing research and technology in service to the people of the community and to Canadians."

The University of Waterloo Research and Technology Park is one of 26 research parks in Canada. As of 2011, Phase I of the park is fully committed and will accommodate 1.6 million square feet of office space on 120 acres (49 hectares) of land north of Columbia and east of Laurel Creek. When completed, the Park is expected to house over 9,000 knowledge workers, create new technology jobs and generate billions of dollars in economic impact.

Afterwards, Johnston will head to the Perimeter Institute building in central Waterloo, where he will attend the 1:00 launch of the Equinox Summit, the first public event organized by the Waterloo Global Science Initiative. WGSI is a partnership of Perimeter and the university, mandated "to catalyze long-term thinking and solutions to the world's most fundamental social, environmental and economic challenges, using science and technology. WGSI provides a rare opportunity for great minds to come together, share new ideas and collectively work towards a better future."

The Governor General will give the opening address at this year's summit, which focuses on energy issues, "speaking on the importance of innovation and collaboration in developing solutions for future energy use and supply," according to a news release from Rideau Hall.

Over the ensuing four days, the Equinox Summit "will examine the world's energy concerns and the need for cleaner and more sustainable production, distribution and storage of electricity. The summit is unique in that it brings together pioneering scientific experts with next-generation leaders from around the globe, all of whom are supported by the mentorship of seasoned advisors from the fields of science, engineering, public policy and industry. The summit is focused around the co-operative creation of a blueprint document that shortlists a set of key technologies that could transform the current carbon-heavy scenario, as well as provide a roadmap on how to implement these innovations by 2030."

Johnston, who is busy in Ottawa today reading the Throne Speech as Canada's 41st Parliament gets to work, was in Stratford, west of Waterloo, on Monday. Before attending a gala opening at the Shakespeare Festival, he toured the university's Stratford campus — which can't have been much of a surprise to him, since he was president as the campus was being planned and moved into its temporary Wellington Street quarters.

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New look at the ‘double-slit experiment’

One of the fundamental rules of quantum physics — that you can't observe a quantum system without changing it — has been uniquely skirted (but not broken) by a researcher at Waterloo’s Institute for Quantum Computing, along with collaborators at the University of Toronto.

The researchers, including IQC postdoctoral fellow Krister Shalm, describe in the latest issue of Science how they succeeded in mapping the paths of photons (quantum particles of light) without actually disrupting those photons through direct observation.

To achieve their result, the researchers started with one of the most iconic experiments in physics — the famous double-slit experiment, known for nearly a century as an elegant demonstration of quantum mechanical effects. When a beam of light is shone through a pair of thin slits, the photons imprint a screen on the other side with a distinctive interference pattern. The original experiment, and the debates between Niels Bohr and Albert Einstein that ensued in 1927, seemed to establish that you could not watch a particle go through one of two slits without destroying the interference effect: you had to choose which phenomenon to look for.

But in a recent experiment at U of T, the researchers succeeded in experimentally depicting, for the first time, the trajectories the photons travelled through the experiment to form the interference pattern.

"With recent advances in technology we have gained the ability to control and manipulate the quantum world in exquisite detail," said [Shalm]Shalm, a co-author of the paper,  titled Observing the Average Trajectories of Single Photons in a Two-Slit Interferometer. "We can now study quantum systems in ways that were previously thought to be impossible." (Shalm, left, is scheduled to be interviewed tomorrow on CBC radio's "Quirks and Quarks".)

To measure the trajectories of photons, the researchers built upon new advances in "weak measurement" developed by Yakir Aharonov's group at Tel Aviv University. Howard Wiseman of Griffith University proposed that it might be possible to measure the direction a photon was moving, conditioned upon where the photon is found. By combining information about the photon's direction at many different points, Wiseman suggested one could construct its entire flow pattern (that is, trace the trajectories the photons travel toward the screen).

Using a new single-photon source developed at the National Institute for Standards and Technology in Colorado, the team sent photons one by one into a two-slit interferometer constructed at Toronto. The researchers then used a quartz calcite, which has an effect on light that depends on the direction the light is propagating, to measure the direction as a function of position. This resulted in a kind of roadmap showing the paths that photons travelled, consistent with theoretical predictions.

The original double-slit experiment played a central role in the early development of quantum mechanics, leading directly to Bohr's theory that observing particle-like or wave-like behaviour in the double-slit experiment depends on the type of measurement made — the system cannot behave as both a particle and wave simultaneously.  The new paper published in Science suggests this doesn't have to be the case: the system can behave as both.

By applying the "weak measurement" techniques to the historic double-slit experiment, they observed the average particle trajectories undergoing wave-like interference — the first observation of its kind.  

"This opens up the opportunity to develop new technologies based on quantum mechanics, such as quantum cryptography and computing, that can solve problems out of the reach of classical physics," said Shalm, who co-authored the paper with lead investigator Aephraim Steinberg, Sacha Kocsis, Boris Braverman, Sylvain Ravets, Martin Stevens, and Rich Mirin.

The experiment was a beautiful new method for approaching one of the most fundamental concepts in quantum mechanics, Steinberg concluded: "We are all just thrilled to be able to see, in some sense, what a photon does at it goes through an interferometer — something all of our textbooks and professors had told us was impossible."


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Link of the day

Summit, 50 years ago today

Hitchens tickets available

Some tickets are available again for Saturday's debate featuring God is Not Great author Christopher Hitchens and Barry Brummett (University of Texas at Austin). They'll speak in the Humanities Theatre, 7 p.m., on the topic of "Religion has been a positive force in culture." Says Fraser Easton of Waterloo's English department, which is sponsoring the event: "Despite a recent round of harsh anti-cancer therapy, during which he temporarily lost his voice, Hitchens will be attending the event live by professional video link. Because Hitchens will appear by video, a small number of tickets to the main venue for this event have been returned and are now available. These tickets are $20 each and may be ordered from the Humanities Theatre box office. An overflow site has also been arranged at the Theatre of the Arts. Tickets for the overflow site are $10 each. The debate is the plenary session of the Department of English Language and Literature's 50th anniversary conference on Literature, Rhetoric, and Values running Friday through Sunday."

When and where

Optometry continuing education weekend Friday-Sunday. Details.

Warrior hockey PA Day camp for students aged 7-12, Columbia Icefield, information ext. 32635.

Child care festival organized by day care centres, guest performer Erick Traplin, 9:45, Village green.

Midnight Sun X solar car unveiling 11 a.m. (car appears at noon), Engineering 5 first floor.

Spring Rainbow Social for LGBTQQ faculty and staff and allies, 4:30 to 6 p.m., University Club Burgundy Room.

School of Optometry Bobier Lecture by Susan Barry (“Stereo Sue” ) 5 p.m., Optometry building room 1129. Details.

Student Developer Network hackathon, Friday 6 p.m. to Saturday 6 p.m., location to be announced. Details.

International Development student fundraiser: Roy Sesana, Botswana medicine man, speaks (with interpreter) on land claims issues in the Kalahari, 7 p.m., Davis Centre room 1350. Donation requested.

Niagara wine tour sponsored by staff association Saturday, tickets $75 (members), $85 (non-members).

Niagara Falls and winery tour sponsored by International Student Connection, Saturday, tickets $23 at Federation of Students office, Student Life Centre.

Bike repair workshops sponsored by WPIRG and Bike Centre, Saturday and June 18, noon to 5 p.m., Student Life Centre room 101A. Details 519-888-4882.

Star Performance Academy dance production, Saturday 1:00, Humanities Theatre.

Equinox Summit: Energy 2030 sponsored by Waterloo Global Science Initiative , June 5-9.

Centre Stage Dance performance Sunday 2:00, Humanities Theatre.

Commuter Challenge June 5-11: register ; questions to Mark Lisetto-Smith, ext. 38257.

Class enrolment appointments for fall term undergraduate courses: continuing students, June 6-11; for first-time students, July 11-24; open class enrolment, July 25.

President’s Golf Tournament in support of Athletics Excellence and Awards Fund, Monday, Westmount Golf and Country Club. Details.

Senate executive committee Monday 3:30, Needles Hall room 3004.

International spouses “walk and talk” event: concert at Waterloo Public Square, Monday 7:15 p.m. Information: intlspouses@

Keystone Campaign picnic, Tuesday 11:30 to 1:30, Graduate House green (rain location: Student Life Centre).

Vic Neglia, Arts Computing, retirement party recognizing 39 years at Waterloo, June 10, 3 to 5 p.m., Laurel Room, South Campus Hall, information ext. 35206.

Keystone Campaign annual event for evening staff, June 10, 6 p.m., Environment 1 room 250.

Board of governors meeting June 14, 2:30 p.m., Needles Hall room 3001.

Spring Convocation: Wednesday, June 15, 10 a.m. (AHS and environment) and 2:30 p.m. (science). Thursday, June 16, 10 a.m. and 2:30 p.m. (arts). Friday, June 17, 10 a.m. and 2:30 p.m. (mathematics); Saturday, June 18, 10 a.m. and 2:30 p.m. (engineering), all ceremonies in Physical Activities Complex. Details.

Deadline for 50 per cent tuition fee refund for spring term courses, June 17.

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