Lakshmi Chandrasekaran

It’s not easy to study quantum systems — collections of particles that follow the counterintuitive rules of quantum mechanics. Heisenberg’s uncertainty principle, a cornerstone of quantum theory, says it’s impossible to simultaneously measure a particle’s exact position and its speed — pretty important information for understanding what’s going on.
In order to study, say, a particular collection of electrons, researchers have to be clever about it. They might take a box of electrons, poke at ...

Simons Institute

In this episode of our Polylogues web series, Summer 2023 Science Communicator in Residence Lakshmi Chandrasekaran interviews former Simons Institute Scientific Advisory Board member and program organizer Irit Dinur. Their wide-ranging conversation touches on Irit’s career and research, the trajectory from basic science...more

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The global population continues to face the detrimental effects of food insecurity and climate change, with an estimated 1.3 billion people having experienced food insecurity in 2022 [4]. At the 2023 United Nations Climate Change Conference (COP28)—which took place last December in Dubai, the United Arab Emirates (UAE)—more than 150 countries endorsed the COP28 UAE Declaration on Sustainable Agriculture, Resilient Food Systems, and Climate Action. This global commitment aims to better a...

Introduction

Theoretical computer scientists deal with complicated ideas. But whenever possible, they’d prefer to work with simpler ones. A 2009 tool known as the regularity lemma gives them a great way to do this. It effectively lets them break a given computational problem or function into simpler pieces.

For computational complexity theorists, who study the relative hardness of different problems, this ability to simplify has long helped them understand unwieldy mathematical functions. But...

Physicists have done a remarkable job explaining the chaos of the universe with well-behaved equations, but certain situations remain mysterious. Among these are collections of many tiny particles — they can be atoms, electrons, anything sufficiently small — that interact in surprising and complicated ways. These interactions gi...

Quantum computers are poised to become computational superpowers, but researchers have long sought a viable problem that confers a quantum advantage — something only a quantum computer can solve. Only then, they argue, will the technology finally be seen as essential.

Even after decades, they’re still looking. “Part of the reason it’s challenging is because classical computers are pretty good at a lot of the things they do,” said John Preskill, a theoretical physicist at the California Instit...

Have you noticed how oranges are stacked at the store? Grocers know that the most attractive and stable arrangement is a pyramid. Johannes Kepler suspected this pyramid-stacking was superior, way back in the 17th century. But the German scientist also noted that he couldn’t prove it. Sadly, like Kepler, many mathematicians may never live to see the confirmation of their discoveries. Or the full impact of their insights.
In Kepler’s case, it took nearly 400 years for mathematicians to confirm ...

Introduction

The traveling salesperson problem is one of the oldest known computational questions. It asks for the ideal route through a certain list of cities, minimizing mileage. Despite seeming simple, the problem is notoriously difficult. While you can use brute force to check all the possible routes until you find the shortest path, such a strategy becomes untenable after just a handful of cities. Instead, you can apply a rigorous mathematical model called linear programming, which rough...

Understanding the quantum universe is not an easy thing. Intuitive notions of space and time break down in the tiny realm of subatomic physics, allowing for behavior that seems, to our macro sensibilities, downright weird.

Quantum computers should allow us to harness this strangeness. Such machines could theoretically explore molecular interactions to create new drugs and materials. But perhaps most important, the world itself is built upon this quantum universe — if we want to understand how...

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As the world began to cautiously emerge from the ravages of COVID-19 in early 2022, a new global outbreak arose: monkeypox/mpox, a viral infectious zoonotic disease. According to the World Health Organization (WHO), the virus has spread to 110 countries thus far. WHO also reported that smallpox vaccines are roughly 85 percent effective in preventing mpox. Nevertheless, public health experts still debate a central question: Should public policy mandate vaccinations to prevent the spread ...

Imagine you’re a general in ancient times and you want to keep your troop counts secret from your enemies. But you also need to know this information yourself. So you turn to a math trick that allows you to achieve both aims.
In a morning drill you ask your soldiers to line up in rows of five. You note that you end up with three soldiers in the last row. Then you have them re-form in rows of eight, which leaves seven in the last row, and then rows of nine, which leaves two. At no point have y...

When the first transistor was created, in 1947, few could have imagined the eventual impact of this device—the switch that lies at the heart of logic chips.
We have silicon to thank for computing’s great takeover. Add a minute pinch of impurities to the element, and silicon forms a material almost ideal for transistors in computer chips.
For more than five decades, engineers have shrunk silicon-based transistors over and over again, creating progressively smaller, faster, and more energy-effi...

A NASA mission is sponsoring undergraduate research to test space-based manufacturing.

If we’re going to go to Mars — maybe not so far off with SpaceX founder Elon Musk already planning human flights there — we’d better be ready to produce necessities when we get there.

Given that it takes nearly 300 days to reach Mars from Earth, imagine the time, the number of trips, the weight of materials to be carried and the cost to sustain even a small community. Could a better alternative be to figure...

Physicist Elisabetta Matsumoto is an avid knitter and has been since taking up the hobby as a child. During graduate school at the University of Pennsylvania in 2009, Matsumoto came across an unusually knotty stitch while knitting a pattern for a Japanese red dragon. “I have books with thousands of different stitch patterns, but the one in the red dragon wall hanging was one I had never seen,” she says. That got her thinking about the geometry of stitches and, eventually, led her to study the...

By Lakshmi Chandrasekaran
The house came down piece by numbered piece. In mid-September, the House by Northwestern (HBN) team dismantled the entire home they built over the summer, and FedEx-ed it off to Denver.
The solar-powered sustainable house, Enable is an official entry in the eighth Solar Decathlon competition, sponsored by the United States Department of Energy. Northwestern University will be participating for the first time.
The Solar Decathlon features a total of 11 collegiate team...