How does the air we breathe affect our body’s reaction to COVID-19? Early on in the pandemic Francesca Dominici, Gamble professor of biostatistics, population, and data science at the Harvard T.H. Chan School of Public Health, explored this question with her team. On this episode, she discusses the links between fine particulate matter in the air and COVID-19 outcomes. Dominici also discusses the pressure placed on scientists by government and media during public health crises—when answers are needed before conclusions exist. She concludes by describing how the government could help scientists reach conclusions faster, by collecting and releasing more (and better) data to scientists.

Climate change is out of control, leading many people to question whether it isn't just fossil fuels, but our entire economic system, that needs to be replaced. In this episode, Harvard Business School economist Rebecca Henderson talks through her own efforts to reconcile the climate crisis with her faith in the ingenuity of capitalism. "I believe that at the moment, our capitalism is also neither free nor fair," she says. "The free market works when everyone can take part, and prices reflect real costs"—when polluters have to pay the cost of emitting fossil fuels. Henderson's smart, original vision for recalibrating capitalism to meet the linked crises of climate change and extreme inequality is a must-listen.

Decades of Supreme Court precedent says colleges can use affirmative action in admissions—but the court's new composition could change all that. In this episode, Harvard Law School professor Jeannie Suk Gersen breaks down everything you need to know about the lawsuit alleging that Harvard discriminates against Asian Americans in admissions. She explains why the stakes of this case may be different from what you think, and why the question of whether Harvard discriminates against Asian Americans can be treated separately from affirmative action. And she speaks so poignantly about her own experience as an Asian-American in elite institutions: "At some point in my past," she says, "I might've been one of the students who might've been rated lower" by the "personal" score used in Harvard's admissions process. This is a moving, wide-ranging conversation that goes deeper than most analyses of the admissions lawsuit.

America's response to the COVID-19 crisis, says political philosopher Danielle Allen, represents "the biggest possible announcement one could have of the broken state of affairs" in our nation's democracy. Allen has helped lead one of the most authoritative national reports on the combination of testing and contact tracing needed to contain the pandemic, as well as an ambitious proposal for reinventing American democracy through an enlarged House of Representatives, ranked-choice voting, and more. In this episode, the political philosopher explains why the COVID crisis, extreme inequality, and undemocratic government are all connected—and how democracy in America can still be reinvigorated. "Failure with regard to democracy is, for me, simply not an option," she says. "I'm not an optimist, and I'm certainly not a pessimist. What I am is a not-an-optionist."

Can cellphone technologies play a role in controlling the coronavirus pandemic? Knowing how public health policies interact with people’s actual behavior, even at an anonymous population-level view, can help guide the decisions of leaders. Mobile phone location data can reveal large-scale patterns of activity and travel between regions. In this episode, associate professor of epidemiology Caroline Buckee explains how such data—carefully stewarded to ensure individual privacy—can even be used to help predict where outbreaks are likely to flare next.

Climate change may be the hardest problem the human race has ever confronted. In a single century, humans have set in motion events that will unfold on a geological timescale, ultimately redrawing coastlines around the globe as ice sheets melt and sea level rises. Can humanity agree to meet its energy needs with renewables such as wind and solar power? Is there a threshold beyond which the effects of greenhouse gases will become irreversible? Can solar geoengineering help stop this runaway train? In this episode, Daniel Schrag, director of the Harvard University Center for the Environment and Sturgis Hooper professor of geology and professor of environmental science and engineering, and David Keith, the Gordon McKay professor of applied physics in the School of Engineering and Applied Sciences, and professor of public policy at the Harvard Kennedy School discuss the ramifications of climate change and an engineered response.

We’re delighted to bring you Season Three of Ask a Harvard Professor. Each week, our editors, Jonathan Shaw, Marina Bolotnikova, and Jacob Sweet will interview some of the world’s most prominent scholars and discuss discuss everything from climate change to capitalism to COVID-19. Join us for podcasts with Daniel Schrag and David Keith on geoengineering and Jeanie Suk Gersen on the Students for Fair Admissions lawsuit against Harvard, among several others. We look forward to sharing these conversations with you.

EVEN BEFORE THE CORONAVIRUS SHIFTED THE U.S. ECONOMY INTO LOW GEAR, demanding a massive stimulus in response, federal debt as a percentage of GDP was as high as it had been since the years following World War II. Simultaneously, given the nation’s aging population, spending on benefits for older Americans was and is expected to skyrocket. Should voters be worried? Why would curbing federal deficits now be a mistake? In this episode, recorded before the coronavirus arrived in the United States but perhaps even more pertinent now, Price professor of public policy Douglas Elmendorf, who is dean of the Harvard Kennedy School, and professor of the practice of economics Karen Dynan argue that this is the moment for the U.S. government to borrow.

CHINA IS THE MOST POPULOUS COUNTRY ON EARTH, and until a few hundred years ago, it was also the most economically powerful. Today, China is ascendant on the world stage. What does its government seek in its relationship with the United States? Do China and the U.S. share common goals with respect to nuclear North Korea? How far will China press to reunite with Taiwan? What are the country’s economic prospects, and is the perception that it is governed by engineers accurate? How is China coping with pressing issues of the day, from climate change to coronaviruses? In this episode, William Kirby, Chang professor of China studies and Spangler professor of business administration, considers China’s aspiration to lead internationally in the twenty-first century.

Why would it take an Amazon worker, employed full time, more than a million years to earn what its CEO, Jeff Bezos now possesses? Why do the richest 400 Americans own more wealth than all African-American households combined? And how are these examples of extreme income inequality linked to the political disenfranchisement of the lower- and middle-income classes? The established “solutions” for restoring balance to economic and political power in the United States have been tax increases on the rich, on the one hand, and campaign-finance reform on the other. But in this episode, we’ll explore the idea that retooling labor laws for the modern economy may be the most effective way to address both these issues. Harvard Law School’s Kestnbaum professor of labor and industry Benjamin Sachs, together with Sharon Block, executive director of the school’s Labor and Worklife Program, explain.