Shrapnel and Stones

Can politics coexist with science? Sometimes, we have to make a choice.

“Surely, we can distinguish melted shrapnel from stones,” I noted during an online meeting of the Galileo research team last week. We were planning the machinery for an expedition to the Pacific Ocean, to retrieve fragments from the 2014 explosion of the first interstellar meteor.

As shown in a recent paper I wrote with the students Amory Tillinghast-Raby and Amir Siraj, air friction should have brought down the tiniest spherules just under to the explosion site and larger fragments farther along the original line of motion of the meteor up to its intersection with the ocean surface. The fragment size distribution depends on the unknown material composition of the meteorite. The object was tougher than all other 272 meteorsin the CNEOS fireball catalog compiled by NASA over the past decade. If the material happened to be an artificial alloy characteristic of a technological space artefact, the expedition might recover centimetre-sized pieces akin to shrapnel. Large pieces could alert us to the structure and not just the elemental composition of this object.

After my statement, I paused for a few seconds of introspection. Why had I used the military metaphor of a “shrapnel”?

It occurred to me that on the previous day I was very moved by watching the recent film All Quiet on the Western Front. Why did the film resonate so much with me?

The answer, when I thought about it, was straightforward. I am the grandson of a German Jew—whose full name I carry: Avi is the nickname for Abraham, which is equivalent to Albert in Germany.

My grandfather, Albert, survived World War I as an artillery cavalry soldier, stuck in the mud for two years in the bloody Battle of Verdun. This was a deadly battle against the French army where 700,000 people died—deaths that, it turned out, were pointless. For all the combat that occurred on the Western Front as the major theatre of the War between 1914 and 1918, the front line remained largely static.

The disregard to human life was displayed in the film through numerous scenes where men were sent to be slaughtered by gun bullets or bayonets for no good reason. These views portray the absurdity of life. Humans can cheer as they march towards their death based on a fictitious narrative of political or military authorities.

The morning after the movie, I was taking my regular class on “Genesis of Life and Stars in the Universe”. This time, I told my students to always question authority.

I mentioned the story of the first PhD thesis in Astronomy at Harvard-Radcliffe. The paper was written in 1925 by Cecilia Payne-Gaposchkin, who discovered that the most abundant element on the surface of the Sun—and the Universe—is hydrogen. However, she was dissuaded from including this conclusion in her thesis: Henry Norris Russel, director of the Princeton University Observatory and the world authority on stars at the time, told Payne-Gaposchkin that her findings were “clearly impossible.”

The moral of this story is that the elemental composition of the first interstellar meteor will be decided by a mass spectrometer, not by the number of likes it gets on Twitter.

I never met my grandfather Albert, but I remember inheriting the bayonet and cavalry picture he kept as memorabilia from the War. When Hitler came to power, my grandfather received a medal as one of the few German heroes who survived the War, but he ended up throwing it away.

A Nazi official gave a speech in front of a crowd at Albert’s home town, Netze (in the vicinity of Frankfurt), and remarked on how the Jews were using up the German society for their personal benefit. My grandfather was obviously upset to hear that. He stood up and remarked that he fought for Germany in the War, while the speaker chose to be a communist and dodge the draft at that time. The Nazi speaker replied: “We all know about your patriotism, Mr. Loeb; I was referring to the other Jews.”

After hearing that and consulting with German friends, Albert decided to leave Germany.

In the decade that followed, he lost 65 of his family members who were not as concerned as he was, and planned to leave on the last train if German politics would deteriorate. That last train led not out of Germany, but to the concentration camps where they lost their lives.

Today, this history is encapsulated by Google Maps showing a street named in honour of my grandfather, the “Albert Loeb Weg” at his home German town.

How can we understand the horrors of history? Humans live for merely one part in a hundred million of the Sun’s lifespan, yet they happily engage in bloody battles that shorten their lifespan even farther.

If the universe is pointless, as suggested by the Physics Nobel Laureate Steven Weinberg, our actual lifespan does not really matter. “To decide whether life is worth living is to answer the fundamental question of philosophy,” wrote the literature Nobel laureate,Albert Camus, at the opening of his philosophical essay The Myth of Sisyphus. Camus then added: “Everything else … is child’s play; we must first of all answer the question.”

I bet that the soldiers in World War I, including my grandfather, had no uplifting answer to Camus’ question. The distinguished scientific career of one of them, Karl Schwarzschild—the Jewish director of the Astrophysical Observatory at Potsdam—was prematurely terminated at age 42, after he volunteered out of German patriotism to join the Russian front in May 2016.

While in Russia, Karl wrote two papers on Albert Einstein's theory of general relativity and one on Max Planck's quantum theory. The quantum theory paper explained the Stark effect, involving the splitting of the spectral lines of hydrogen by an electric field. Schwarzschild's relativity papers give the first exact solution of Einstein's equations of gravity, deriving the spacetime around a point mass. He sent the first paper to Einstein, who replied: “I had not expected that one could formulate the exact solution of the problem in such a simple way.” Schwarzschild’s solution laid the foundation for our current scientific understanding of black holes a century later, including their images.

How many more scientific breakthroughs would have been made by Karl Schwarzschild or other scientists in the absence of World War I or II? How much more scientific knowledge would have humanity acquired if it invested its annual military budget worldwide, amounting currently to 2 trillion dollars, in space exploration? With this much money per year, we could have launched CubeSats to every star within the Milky Way galaxy within this century. Here’s hoping that the first interstellar meteor was sent towards the Sun by an intelligent civilization who favoured the benefit of scientific exploration over mutual destruction by politics on their home planet.

The reason I seek a higher intelligence in outer space is because I do not find it on Earth. To paraphrase on John F. Kennedy’s "We Choose to Go to the Moon" speech: We choose to find our interstellar partners not in order to get more likes on social media, but to claim our status in the class of intelligent civilizations within the Milky Way.

The subdued mood brought about by the film was washed away by three acts of kindness a day later. First, a brilliant MIT postdoc, Rohan Naidu, who led the most exciting recent analysis of the Webb telescope data on the first galaxies, visited my office and thanked me for writing letters on his behalf years ago that allowed him  to enter the United States when he applied for a visa as a beginning student. “Without your help, I would have never made it,” he noted at the end of our conversation. He made my day.

At the end of my class on the same day, Abby White—who graduated from Wellesley College and is leading the instrumentation effort for the Galileo Project, thanked me for my mentorship during the past year. She also made my day.

Minutes later, my former student, Nick Stone, showed up in my office to thank me for my support over the years. He arrived to receive the Bok Prize of the Harvard Astronomy department for excellence in his postgraduate research. Nick followed a reverse trajectory to mine: he was born in the USA, received his PhD from Harvard University and is now faculty at my alma mater, the Hebrew University of Jerusalem—where I received all of my academic degrees.

For the third time in one afternoon, an act of kindness made my day.

So, here we are as humans. Bound by gravity to the surface of a rock we call Earth; capable of acts of kindness or violence. Life feels like swimming through turbulent waters. Some waves carry us down to the ocean floor while others lift us up. During the limited time I have left on this Earth, I am determined to minimize the impact of the downward spiral of politics by celebrating the uplifting moments of scientific discovery and companionship.

The life and premature death of Karl Schwarzschild illustrate the choice we face between science and politics. Here’s hoping that relics of a more advanced extraterrestrial species in the Pacific Ocean will convince all of us to favour science over politics.

I believe we can, metaphorically speaking, separate the shrapnel from the stones.