Inverse Daily

How do you know if you have had Covid-19? One test may have the answer

Plus: A bonus science and chill story on the multiverse.

Covid19 Disintegration. Coronavirus Isolated on White Background.
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Have you had Covid-19? If you’re like most Americans, the answer is “yes” — although you might not have known about it at the time. I’ve yet to get a positive test, but that isn’t conclusive evidence that I have never had Covid-19. There have been several occasions in the pandemic when I was convinced I had the virus — all of the symptoms, none of the positive tests. But there may be another way to know than an at-home rapid test.

This is an adapted version of the Inverse Daily newsletter for Wednesday, May 4, 2022. Subscribe for free and learn something new every day.

Welcome to Wednesday. May the Fourth be with you! In today’s newsletter, discover how one test offers the surest way to determine if you had a past Covid-19 infection, the Webb Telescope’s next moves, and more.

What will it see?


Webb Telescope needs to hit these major milestones next to achieve pivotal “first light”

NASA’s new telescope is close to achieving its first (official) light. Last week, NASA and ESA announced through a series of images of the Large Magellanic Cloud that the telescope’s instruments are now fully aligned.

The Webb is now headed into a two-month phase called the science instrument commissioning, which includes a roughly 20-day evaluation period to test how the Sun’s heat affects the telescope’s instruments.

Once it’s online, researchers worldwide will use time on the telescope to scrutinize planets outside our Solar System and to peer at the farthest galaxies like never before.

According to a post by NASA communications specialist Thaddeus Cesari, the telescope exceeds engineers' most optimistic predictions.

“Webb’s mirrors are now directing fully focused light collected from space down into each instrument, and each instrument is successfully capturing images with the light being delivered to them,” Cesari wrote.

Go deeper.

A boy bathes during a hot summer day in New Delhi on May 3, 2022.


India’s heatwaves: These maps put South Asia’s scorching temperatures in perspective

The world is getting warmer, but some places are getting hotter faster than others. A deadly heatwave is tearing through India and Pakistan as South Asia experiences some of its highest temperatures on record.

March of this year was India’s hottest ever in 122 years. New Delhi, the nation’s capital city, experienced temperatures rising to above 104 degrees Fahrenheit — 40 degrees Celsius — for more than a week. That’s so hot, some of the city’s many piles of trash caught fire, according to some reports. Incredibly, the summer months in this region are only just beginning.

To understand the devastating temperatures, our card story editor Jennifer Walter found some charts and maps that really say it all.

See them for yourself.

A positive Covid-19 at-home test.

Justin Sullivan/Getty Images News/Getty Images

More than half of Americans have had Covid-19 — here’s how to tell if you are one of them

According to a recent CDC report, most Americans have been exposed to Covid-19.

In their study, the CDC used antibody (or “serology”) tests to determine if people had previous Covid-19 infections. While antibodies elicited by the vaccines also combat the virus, they’re slightly different from the antibodies produced by natural infection. That’s because the antibodies produced by the vaccines focus on the spike protein: the “key” that the virus uses to get inside your cells. It’s an effective way to block the virus from getting into your cells but doesn’t look exactly like the antibodies you get from the infection.

By analyzing data taken between September 2021 and February 2022, the CDC says by the final month of 2021, 34 percent of Americans had these antibodies. By February, that number shot up to 58 percent. According to the CDC, the prevalence of these antibodies varied by age, from as high as 75 percent in children aged 0 to 17 and as low as 33 percent in people 65 and older.

Their methods are also your best method: The best, most accurate way to determine if you’ve had a previous Covid-19 infection is a serology or antibody test, though it is not a guarantee. The CDC notes that a small portion of people won’t develop antibodies in response to an infection. Further, some serology tests won’t distinguish between vaccination and disease, so it’s essential to know which test you’re getting.

Go deeper.

What do you think the multiverse is?


60 years ago, science and superheroes both invented the multiverse

In 1957, physicist Hugh Everett III staked and lost his reputation when he first proposed the many-worlds interpretation or MWI. In a nutshell, MWI theorizes that all possible results of a quantum experiment or action are realized in another world, branching off from that point.

In quantum physics, the state of the tiniest particles has several possibilities until you look at them. In the many-worlds interpretation, once you look, a new “world” is created where the particle is in the opposite state of the one observed by scientists in our world. It adds up to an almost infinite number of realities since quantum particles are the building blocks of all matter around us. (Community episode “Remedial Chaos Theory” is a humorous demonstration of MWI. It also birthed the multiverse meme the “darkest timeline.”)

MWI was such an unpopular idea that Everett was ostracized in his field. His ideas were ignored until later in his life, when, in the 1970s, the discovery of quantum decoherence — basically the understanding that quantum particles are continuously thrown out of state (and thus, coherence) by the environment around them in experiments — lent MWI and Everett greater credibility. Even today MWI is still in dispute, but neither MWI nor Everett has vanished from memory.

While scientists ignored Everett, comic books embraced his ideas — by accident.

Science and chill.

Three young Freedom Riders.

Afro Newspaper/Gado/Archive Photos/Getty Images

About this newsletter: Do you think it can be improved? Have a story idea? Want to share a story about the time you met an astronaut? Send those thoughts and more to

  • On this day in history: On May 4, 1961, the first Freedom Ride took place. The initiative called out racial segregation on interstate buses and bus stations.
  • Song of the day: My Beloved Monster,” by The Eels (frontman Mark Everett is Hugh Everett III’s son).

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