Ellery Frahm is an archaeologist who unearths artifacts spanning half a million years of human history, all around the globe. But he recently unearthed a perplexing ancient artifact close to home. It was a Post-it note from last March, recovered from the debris of his Yale University office.

Written on it? A phone number. Whose number? A mystery.

“I suppose I could call it and ask, and say who I was, and what did they want?” he says.

But that would be a bit awkward, wouldn’t it? More than a year later? Who we were then, what we wanted — it was different.

Frahm is one of many office workers who were abruptly sent home last year and never summoned back until now. They have returned to workspaces frozen in time, full of strange relics: Notes for projects abandoned long ago. Dusty tchotchkes. Expired snacks. Unwashed coffee mugs. Hand sanitizer stations installed at the very beginning of the pandemic, back when we thought maybe a few weeks of germaphobia might get us over.

The scene in his office reminded Frahm, in a way, of Pompeii, the city frozen in time in 79 A.D., when nearby Mount Vesuvius erupted and buried the city in volcanic ash. Residents who fled or perished left their bread in the ovens; their shops were found mostly intact. In a recent wave of excavations, “Many inscriptions, tangible evidence of daily life, also came to light,” says Massimo Osanna, the archaeological site’s director.

Nonessential workers returning to their offices are now discovering tangible evidence of daily life before soft pants and Zoom meetings became ascendant. Quotidian things were left behind in a hurry.

It was the calendars for Vanessa Jae. A few weeks ago, after getting her first vaccine dose, the 25-year-old logistician from Sterling Heights, Mich., went back to her office for the first time in a year to collect some documents she needed.

“Most of us have calendars up, and to see March 2020 even though it’s 2021 kind of spooked me a little,” says Jae.

Because her colleagues had expected to be out for only two weeks, there were papers spread out on desks, as if people had just stepped away for a few minutes. There were a few coffee pots that still had coffee — and probably mold — inside. At her own tidy desk, by the “Hustle” coffee cup and the jar of pens, she threw away some half-finished bags of snacks.

Tim Halbach, a 41-year-old meteorologist for the National Weather Service, visited his Milwaukee office a handful of times in 2020, but not since October. When he returned last month, he opened the break room fridge and was about to stash his turkey sandwich in his usual back-corner spot when he was surprised to see a turkey sandwich already there.

It was his sandwich. His five-month-old sandwich. He’d brought it in last fall and forgotten it after deciding to get a takeout burger instead.

The sandwiches were identical. The old one did not show any signs of mold or decay.

It was unsettling. Was the rot nonexistent, or just invisible? Was the sandwich a metaphor for the New Normal?

Amanda Hills, 24, got a new job in politics during the pandemic. Back in March, “The election was so many months away, it didn’t even cross my mind that I would never be back at the office.”

She returned last month to turn in her identification badge, pack up the toiletries and notebooks she had left there a year ago and take one last look at the kitchen cleaning chart, which still listed duties for the third week of March, 2020.

“All the old personality and like, liveliness that this office had was completely gone, but I feel like you could see the remnants of it,” she says. “All these weird reminders of what life used to be like.”

Some people are calling their offices time capsules, though that’s not quite right because there’s no intention to what was preserved, says Nick Yablon, an associate professor of history at the University of Iowa, who studies visual culture and memory. What makes the still life of an abandoned cubicle fascinating, he says, is the weight “of some kind of gulf, some kind of massive event that separated us from our own past.”

Many people have been working from their offices all year. But for those who have not, the office may stir up unsettling feelings.

“It was kind of relieving to be back, and at the same time, it was just like an overwhelming sense of sadness,” says Ralph Esperas, a 33-year-old marketing coordinator in Scottsdale, Ariz. Seeing his dusty desk made him think of lost time and lost lives.

Jae’s bulletin board still has photos of her with her work friends; with no meetings or happy hours or lunches anymore, those friendships have languished. “We all started to drift apart,” says the Michigan logistician. “And I’m guessing work is what kept us together as a group.”

“I think seeing all of those things in place, like my jacket hung on my chair and that coffee mug there, like, really drove home how much of my personal life has changed,” says Alex Grimaudo, a graduate student at Virginia Tech. Grimaudo studies infectious disease (no, not the coronavirus) in bats, which is hard to do from home. He could not complete much of his fieldwork this year, and was forced to change his entire dissertation. Being back in his old space, surrounded by his old papers, “felt like ages ago,” he says. “I felt like walking into sort of a personal museum.”

As more people return to their offices, those museums will be dismantled without ceremony. The accumulated dust will be swept away, the dead plants trashed, old calendars replaced.

Frahm, the Yale archaeologist, describes a thought experiment that often comes up in introductory courses: “If campus was just abandoned tomorrow, what would be left behind?”

The tables and chairs. Coat hangers. The bulky desktop computers. The signs urging us to keep six feet apart. Whatever is in the wastebasket.

“Often in archaeology, really what we’re dealing with is people’s trash,” says Frahm.

Which might include a Post-it note with a mysterious number, a tiny memorial to questions never answered and purposes long forgotten.

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