Great Scott! 70 Years of the Flux Capacitor

Here's a red-letter date in the history of science: November 5th, 1955. Yes! Of course! November 5th, 1955! That was the day I invented time travel. I remember it vividly. I was standing on the edge of my toilet hanging a clock, the porcelain was wet, I slipped, hit my head on the sink, and when I came to I had a revelation, a vision… A picture in my head, a picture of this – this is what makes time travel possible!

Doc Brown – Back to the Future (1985)

It was seventy years ago today when Dr. Emmett Lathrop “Doc” unfortunate slip gave rise to one of cinema’s most iconic fictional inventions: the flux capacitor. And the world of science fiction was never quite the same.

The brilliance of this origin story lies in its absurdity. The inventor of time travel isn’t a Nobel-hungry physicist or a Silicon Valley wunderkind – he’s an eccentric loner who, quite literally, stumbles into the biggest breakthrough in sci-fi history. Back in 1985, that was part of the joke. Here in 2025, it feels rather familiar.

Some of the world’s most enduring technologies – from Tim Berners-Lee dreaming up the foundations of the World Wide Web as a side project at CERN, to James Dyson doggedly iterating through 5,127 prototypes for the first bagless vacuum – began with obsessive minds quietly tinkering away.

So what can we learn from this oddball innovator? Doc Brown is part genius, part chaos, and utterly unforgettable. Was he really onto something with the flux capacitor? And what does his decision to pour three decades – and his family’s entire fortune – into chasing one “impossible” idea tell us about the power (and price) of relentless curiosity?

The Physics of a Fake Machine

Let’s be honest – the flux capacitor is the narrative equivalent of a magician waving a wand: abracadabra and… time travel! Doc gestures at a glowing Y-shaped device and we accept that the impossible is suddenly possible. Crucially, the film never bothers explaining how it works, because it doesn’t need to – the mystery is part of the charm.

Modern physics doesn’t outright forbid time travel – it just makes it incredibly awkward. Einstein’s theory of general relativity (the physicist, not Doc’s dog) tells us that space and time form a single, flexible fabric that can bend and twist. Gravity, in this view, isn’t so much a force as the curvature of that fabric. And within Einstein’s equations lurk theoretical paths called “closed timelike curves,” where an object could, at least mathematically, loop back to an earlier point in time.

In the late 20th century, physicist Kip Thorne and colleagues pushed this further, exploring whether wormholes – hypothetical tunnels through spacetime – could be repurposed as time machines. Their maths said yes… with one enormous catch: you’d need “exotic matter” with negative energy density to hold a wormhole open. That’s allowed on paper, but no one has ever found it in a form that would let you drive a car through time.

Still, this makes the flux capacitor feel less like pure fantasy and more like a playful extension of real theory. Back to the Future sprinkles just enough jargon – gigawatts, plutonium, flux – to anchor the idea, then floors the accelerator. The science becomes set dressing for the story, and we’re just along for the ride.

But isn’t that how most advanced technology feels from the outside anyway? Few of us could explain how a neural network recognises faces, how GPS quietly corrects for relativistic time dilation, or how CRISPR edits DNA with such breathtaking precision. We accept the unknown because the outcome works – and that’s usually enough to keep the magic alive.

What the flux capacitor really reveals is a deeper truth: major breakthroughs often begin as intuition, with understanding scrambling to catch up. Doc had the vision long before the rationale – and science, time and again, advances in much the same way.

The DeLorean – Failure Reimagined

The way I see it, if you're going to build a time machine, why not do it with some style?!

With the flux capacitor at its heart, Doc’s time machine needed a suitably futuristic shell – and what better than a DMC DeLorean?

The real car was, infamously, a commercial flop: underpowered, overpriced and overhyped. By 1982, DeLorean Motor Company had already gone under – three years before the film graced cinemas. On screen, however, it was perfect. Stainless-steel panels, a sharp wedge profile, gull-wing doors that opened like a sci-fi butterfly – it looked every bit the machine of the future.

Designer John DeLorean’s own story feels oddly on-brand. An engineer turned maverick automaker, he was rebellious, eccentric, equal parts visionary and disaster magnet – sharing more than a little DNA with Doc Brown. And although his car faltered on the road, it found immortality on screen.

This captures something important about innovation: success is rarely linear. The inventions that change the world aren’t always the ones that succeed first, or even at all. Sometimes a product flops, then finds a second life in a completely different context. The Apple Newton flopped, but it was ultimately reborn as the iPhone. Early digital cameras were dismissed as toys; now they’re the backbone of smartphones.

The DeLorean became a phenomenon not because it was good, but because it was unforgettable. In Doc’s hands, it transcended its failings and became a time machine – not just on film, but in the collective imagination. And I’m sure I’m not alone in wishing I were one of the lucky few who own one.

The Legacy: A Reminder to Dream Dangerously

Celebrating the invention of the flux capacitor seventy years on may seem ridiculous – but its legacy offers an important reminder. At the heart of Back to the Future lies a tension that real science still grapples with: progress demands imagination, yet imagination often looks irrational at first glance.

If Doc Brown behaved rationally, he would have stopped early, saved his money and found safer hobbies. If Einstein behaved rationally, he wouldn’t have questioned Newton. If Grace Hopper behaved rationally, she wouldn’t have challenged the way computers handled language. Rationality protects what exists; curiosity disrupts it.

Time travel is a perfect metaphor for this. It asks us to confront impossible questions seriously. If we could change the past, should we? If we could see the future, would it help us or paralyse us? Science thrives on uncomfortable questions. The paradox is that asking them takes us to places we didn’t know we could go – even if the answers lie just out of reach.

And that’s why the flux capacitor endures. It represents the moment before the breakthrough: that first spark of inspiration, the sketch on a napkin, the prototype that barely holds together – and the tenacity to see it through. 

It just goes to show, if you put your mind to it, you can accomplish anything!