How a stranger’s kindness during WWII helped give us the Big Bang theory

German-born physicist Arno Penzias escaped the Holocaust with the help of a benefactor he never met. That secret act of generosity changed his life—and our understanding of the universe.

By Katie Sanders
Published 13 Jun 2022, 13:52 BST
Physicist, radio astronomer, and Nobel laureate Arno Penzias—at Bell Labs in this 1985 photograph—co-discovered cosmic microwave ...
Physicist, radio astronomer, and Nobel laureate Arno Penzias—at Bell Labs in this 1985 photograph—co-discovered cosmic microwave background radiation, echoes of the Big Bang that helped establish the best-supported theory of our universe’s origin.
Photograph by Arnold Newman, via Getty Images

On the eve of World War II, the owner of a Belleville, New Jersey, paint shop got a frantic knock on his door. It was a 28-year-old German immigrant named Leo Gelbart, who’d been going door to door, appealing to members of the town’s Jewish community.

“This family needs to get out of Germany, and I don’t have enough money to help. Can you?” Gelbart asked. He showed the store owner a black-and-white photograph of his friends back in Munich: a handsome couple named Karl and Justine Penzias, holding their sons Arno and Guenther, six and four. With German Chancellor Adolf Hitler’s Nazi regime increasingly persecuting and interning Jews, the Penzias family had to flee or face a concentration camp. But to immigrate to America, they needed to secure several affidavits of support — official documents vouching that they had a relative and a financial safety net in the United States. Gelbart would provide the first, falsely stating that his friend Karl Penzias was his cousin. But as a waiter, he didn’t have enough money to qualify as the family’s sponsor. He was trying to find someone to sign the second affidavit taking on the Penziases as dependents in case of need.

The 52-year-old paint merchant said yes, he would help. “I’ll be glad to support them until they become self-supporting,” he wrote on the affidavit. From Germany, a deeply grateful Karl Penzias gave this stranger his word, via his friend, that his family only needed support on paper and would show their gratitude by never contacting him.

The older of the two boys in the photograph, Arno Penzias, is 89 now. A retired Nobel Laureate radio astronomer, he lives in northern California. He was born in Munich in 1933, as Hitler rose to power. In 1938 his family was rounded up with other Jews who held Polish passports and forced aboard a train to Poland for deportation. But their train was delayed, and Poland invalidated their passports just before their train reached the border.

Penzias and fellow radio astronomer Robert Wilson made their famous discovery using the Holmdel Horn Antenna at Bell Labs in Holmdel, New Jersey. An etched glass cube of the horn-shaped instrument commemorates the 50th anniversary of their discovery.
Photograph by Richard Barnes
Barnet Yudin (second from right) and his family pose for a portrait in 1929. In 1938, on the eve of World War II, Barnet signed an affidavit of support for the Penzias family, agreeing to meet their financial needs if necessary and clearing the way for the refugees he never met to escape Nazi Germany.
Photograph by Richard Barnes

In 1939, as they scrambled to make arrangements to leave Germany for America, Arno's parents sent their young sons to England as part of the Kindertransport, a British rescue effort that transported 10,000 mostly Jewish children out of Nazi territory. The brothers bounced around from an all-girls London orphanage to different English foster families. As Nazis accelerated Hitler’s murderous campaign that would give birth to the word “genocide,” Karl and Justine Penzias, equipped with the necessary paperwork, eventually reunited with their sons in England and set out for the U.S. by boat. The family dodged hurricanes and German submarines on their journey across the Atlantic. On January 3, 1940, as their ship docked in New York City, journalists snapped photographs of Arno and Guenther, wide-eyed young refugees waving to the Statue of Liberty.

Photograph by Richard Barnes

The Penzias family settled in the Bronx, where the boys started school and learned English. Arno graduated from Brooklyn Technical High School and City College. He served in the U.S. Army Signal Corps, then earned a Ph.D. in physics at Columbia University. He joined Bell Laboratories and, in the 1960s, he and his research partner Robert Wilson co-discovered cosmic microwave background radiation, which confirmed the Big Bang theory of cosmology. They shared the 1978 Nobel Prize in Physics for the discovery. In a letter he penned in response to a congratulatory telegram from then-President Jimmy Carter, Penzias expressed his gratitude for the chance to live in America:

"I came to the United States thirty-nine years ago as a penniless refugee from Nazi Germany. For my family and myself, America has meant a haven of safety as well as a land of freedom and opportunity. At a time when the promise and meaning of American institutions are often questioned, I feel compelled to bear witness to the fulfillment of the American promise in my personal life experience. I am very proud to be an American, very grateful to America and to the American people. Thus, in your capacity as a representative of the American people, I have taken this occasion to express a small portion of my thanks to them through you.”

But thanking the man whose signature opened the door to America wasn’t feasible. Arno’s father had promised never to contact the signer of the affidavit, and he kept his word. The details regarding their helper remained a mystery.

Barnet Yudin (left) fled Russia for the U.S. in 1906, sold paint from a pushcart, and eventually opened this paint shop in Bellville, New Jersey. According to his affidavit of support, his income was $125 a week.
Photograph by Richard Barnes

Then, in 2012, Arno’s son David Penzias found an envelope in some family papers. Inside was a copy of the affidavit signed by one Barnet Yudin. David leafed through copies of the documents Yudin had provided to certify the affidavit, shocked at how much information this stranger had been willing to disclose: He made $125 (about £25 at the exchange rates of the time) a week as the owner of his paint shop, which he resided above in a building he owned. He had $2,000 (about £400) in his bank account. This man had not only vouched for a family he had no direct connection to; he’d gone to considerable effort to do so. Who was he?

After some online searching, David Penzias dialled a number he found for a Robert Yudin in New Jersey, whom he was pretty sure was Barnet Yudin’s grandson. It was an unexpected call that led to a unique connection. The Yudins were taken aback at first; Barnet had died of cancer in 1950. His wife, son, and daughter were also deceased, and his grandchildren had no recollection of Barnet mentioning a German family he’d aided with an affidavit. But Arno’s son shared the documents, and the puzzle started to come together.

Sydney Neuwirth, a retired artist and Barnet Yudin’s granddaughter, says her grandfather was moved to help the Penzias family because “he knew what it was like to be turned down, turned away.”
Photograph by Richard Barnes
Guenther “Jimmy” Penzias (foreground) was four years old when he and brother Arno reached safety in England as part of a British rescue effort called the Kindertransport. In 2012, Arno’s son David Penzias (background) discovered a copy of the affidavit signed by Barnet Yudin, which until then had remained a secret.
Photograph by Richard Barnes

The notion that Barnet would have put his family’s livelihood on the line to help others fleeing persecution was in keeping with the humble, generous immigrant they knew. More Yudins were looped in and shed light on Barnet’s life: Born in Russia in 1886, he had hoped to become a doctor. He passed his medical school entry exams but was denied admission, allegedly because he was Jewish. He left Russia for the U.S. by way of Scandinavia in 1906. Upon settling in New Jersey, he sold paint from a pushcart, eventually running a successful paint and hardware shop with his wife, Anne.

Barnet’s granddaughter Sydney Neuwirth, a retired artist in Princeton, New Jersey, grew up in one of the apartments her grandfather built above his paint shop. As she sifted through a binder of photos, letters, and newspaper clippings chronicling her grandparents’ lives, Neuwirth felt a deep connection to her grandfather and the family he helped spare. “He knew what it was like to be turned down, turned away,” Neuwirth says. “This was his way of helping. He always wanted to help.” As she reads about the war currently raging in Ukraine—and the resulting refugee crisis, Europe’s largest since World War II—she finds even more perspective.

The Holmdel Horn Antenna towers above Arno Penzias (right) and Robert Wilson in this photograph from 1978, the year the two radio astronomers won the Nobel Prize in Physics.
Photograph by AP
Six-year-old Arno Penzias stands between his parents in this photograph that was shown to Barnet Yudin in 1938. Yudin would never know that the young boy he helped save would one day win the Nobel Prize (facsimile at left).
Photograph by Richard Barnes

Nearly eight decades after Barnet signed the affidavit, his family took David Penzias up on his request to get together. While Arno couldn’t join because of his declining health, his brother and nephew travelled to New Jersey for brunch at Barnet’s grandson’s home. Over a hearty spread of bagels, lox, and whitefish, the families shared documents and memories. David handed out copies of a recent photograph of his father and uncle with their direct descendants. As the Yudins studied the grey-haired patriarchs surrounded by their five grown children and ten grandkids, David said: “None of these people would exist today without Barnet Yudin.” Struck by the implication of what Barnet’s quiet act enabled, a new friendship was born.

Barnet Yudin would never know that the six-year-old he helped bring to America would become one of the most influential scientists of the 20th century. Joe Yudin guesses that his great-grandfather wouldn’t have emphasised that part: “He knew that they got out. I think that’s all he needed. He didn’t say, ‘Is this kid going to win the Nobel someday, or play shortstop for the Yankees?’ He did what he did because it was right and didn’t mention it to anybody. He definitely had this big picture of what humanity should be like.”

The Holmdel Horn Antenna was designated a National Historic Landmark in 1988 for its role in establishing the Big Bang theory. For Penzias, his discovery had greater, even cosmic, significance. “Astronomy leads us to a unique event, a universe which was created out of nothing, and delicately balanced to provide exactly the conditions required to support life,” he wrote. “In the absence of an absurdly improbable accident, the observations of modern science seem to suggest an underlying, one might say, supernatural plan.”
Photograph by Richard Barnes

Yet Joe does find himself thinking about the impact of his great-grandfather’s act. A former Israeli Defence Forces paratrooper, he owns a tour company in Israel and frequently brings visitors from around the world to Yad Vashem, the nation’s official Holocaust memorial. These days, when he reaches Yad Vashem’s Children’s Memorial—a dark underground cavern where flickers of light give the illusion of millions of stars, commemorating the roughly 1.5 million Jewish children Nazis murdered—he frames a question: “What did we lose in the Holocaust?” Beyond an estimated 11 million lives, the world lost the promise of so many children—the youthful faces pictured on the memorial walls. "We lost the cure for cancer. We lost time travel and deep space travel,” Barnet Yudin’s great-grandson speculates, adding, “Think of all the geniuses who didn’t survive.” Then he tells the story of one, Arno Penzias, who did.


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