Shortly after my father died the phone started ringing. My father was Hugh Everett III. When he was 24 he wrote a ground-breaking thesis about physics most commonly known as “the many worlds theory”. It challenged the accepted notion of how the world works in such a huge way, stating that there were actually countless versions of ourselves splitting off and going through as many different scenarios as you could imagine, and the physics powers that be (Albert Einstein, Niels Bohr) were having none of this. They weren’t about to let a 24-year-old knock their faces off the Mount Rushmore of physics. Getting no encouragement, my father gave up on quantum physics.

It’s now considered to be one of the greatest tragedies in physics that my father wasn’t taken seriously. He was so ahead of his time that there weren’t even ways to prove his theory mathematically, but now, 50 years later, there are. And it checks out quite well.

I knew this day was coming ever since the phone started ringing in 1982. It was always some “physics groupie” asking for my mother so they could grill her for information about my father. And, as time went on and technology caught up with him, the interest kept mounting.

I’m a singer and songwriter in a rock band called Eels. I never knew much about physics and my father was a complete mystery to me, even though I lived in the same house with him for 18 or 19 years. He rarely spoke. He was an ever-present lump of flesh sitting at the dining room table every night writing out crazy calculations on a pad of paper. That’s about all I saw of him.

When the BBC asked if I was interested in making a film, I jumped at the chance. I have tended to deal with my family by making them into little art projects. I made an album in 1998 called Electro-shock Blues that dealt extensively with my sister’s and mother’s deaths. While my sister’s suicide note did indeed contain a passage about going off to meet our father in a parallel universe, I hadn’t made anything that dealt with my father the way I had dealt with the rest of my family, and this was the way I liked to do it: make something that is therapeutic for me personally that, hopefully, can offer something for the rest of the world.

The idea made me both excited and uncomfortable. And the uncomfortable part was what made me know it was something I’d have to do. I didn’t like the idea of opening up that world of pain and going back to Virginia and Washington DC, places where I can smell the dread in the air because of all the painful memories. But to get the chance to hang out with my father’s college roommates, who are all still alive, friends and coworkers, was too interesting for me not to go through with. I knew I was going to learn a lot about both physics and my father. And I did.

The first few days of shooting were awkward and I felt pretty uptight. Then one day while I was being interviewed on camera about some painful experience, I heard Louise [Lockwood], the director, softly click her mouth and whisper, “Aw, E...” Suddenly I thought: “These people actually care about me.” I then relaxed and probably started saying all sorts of things I would have been too guarded about before.

I was struck by what a tragedy my father’s life was. He has contributed something huge to the world, but for him it was painful. How would you like to come up with something so mind-blowing about how the world works, confident that you knew it was true, but have no one support your view? It must have been the loneliest life, being the smartest guy in the room, just having to shut up and keep your thoughts to yourself while the regular chimps all chat away. I was determined to help to give him the day in the sun he never got when he was alive.

I spent a week at Princeton learning about physics and hanging out with my father’s old friends. I did not inherit my father’s gift for mathematics, and can barely calculate the tip after dinner, so it was a real challenge for me to be standing in front of blackboards learning about quantum physics. But I came to have a pretty good understanding of my father’s theory. In Virginia I met some of my father’s coworkers and even went inside the Pentagon (who knew security was so lax?).

It was a very difficult process for me, but when it was over I felt really glad that I had done it. It’s not easy going back to a place you really don’t want to go back to and opening boxes of memories. Particularly with a film crew following you, trying to make you cry (“How does that make you feel, E?”). I’d be really glad if I had a son do something like this for me some day, so I’d like to think that my dad is smiling down from some parallel universe and saying, “thanks”.

Parallel Worlds, Parallel Lives, Mon, BBC Four, 9pm

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