Book cover of What If? by Randall Munroe

What If?

by Randall Munroe

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Introduction

Have you ever found yourself pondering seemingly ridiculous questions like "What would happen if the Sun suddenly went out?" or "Could we print a live-updating version of Wikipedia?" If so, you're not alone. Randall Munroe, the creator of the popular webcomic xkcd, has made a career out of exploring these kinds of absurd hypotheticals in his book "What If?: Serious Scientific Answers to Absurd Hypothetical Questions."

In this fascinating and entertaining book, Munroe takes readers on a wild ride through the realm of the impossible, using real science to answer outlandish questions. By applying rigorous research and calculations to these far-fetched scenarios, he not only provides surprisingly detailed answers but also reveals fascinating insights about how our world works.

Let's dive into some of the most intriguing questions and answers from "What If?" and explore the unexpected lessons we can learn from these imaginative thought experiments.

The Sun Goes Out: An Unexpected Silver Lining

One of the most captivating scenarios Munroe explores is what would happen if the Sun suddenly went dark. While our first instinct might be to panic at the thought of eternal darkness and freezing temperatures, Munroe reveals some surprising benefits that would come from this cosmic catastrophe.

Reduced Risk of Solar Flares

Without the Sun, we'd no longer have to worry about the devastating effects of solar flares. These massive bursts of energy from the Sun's surface can cause geomagnetic storms, which pose a significant threat to our technology-dependent world. Munroe reminds us of the infamous 1859 Carrington Event, when a powerful solar storm caused telegraph wires to catch fire and disrupted communications worldwide.

In today's interconnected world, a similar event could cause trillions of dollars in damage to the United States alone. By eliminating the Sun, we'd effectively remove this threat to our infrastructure and economy.

Infrastructure Savings

Another unexpected benefit of a sunless world would be reduced infrastructure costs. Munroe points out that without the Sun, bodies of water would freeze solid, eliminating the need for bridges. Considering that the United States spends around $20 billion annually on bridge repairs, this could lead to significant savings.

Streamlined Global Trade

In a world without the Sun, the concept of time zones would become obsolete. This seemingly small change could have a profound impact on global trade and communication. With everyone operating in a single time zone, businesses would no longer struggle to coordinate across different office hours, potentially boosting economic efficiency worldwide.

Of course, Munroe doesn't ignore the obvious downside: without the Sun, we'd all freeze to death. But his exploration of these unexpected benefits serves as a reminder that even in the most dire scenarios, there can be surprising silver linings – if only we look for them.

Living on The Little Prince's Planet: A Gravitational Adventure

Munroe takes us on a whimsical journey to explore what life would be like on the tiny planet from Antoine de Saint-Exupéry's beloved children's book, "The Little Prince." While such a small planet is impossible in reality, Munroe's calculations reveal some fascinating gravitational quirks that would occur if we could inhabit such a world.

Gravity's Uneven Pull

Imagine a planet with a diameter of just 3.5 meters and a mass of about 500 million tons. Munroe calculates that on the surface, we'd experience Earth-like gravity. However, the gravitational force would decrease much more rapidly than on Earth as we move away from the surface.

This would lead to a bizarre sensation where our feet would feel four times heavier than our heads. Munroe likens this to the feeling of lying on a spinning merry-go-round with your head near the center – a constant stretching sensation that would make for a very unusual living experience.

Running Off the Planet

Perhaps the most exciting aspect of life on this tiny world would be the ability to literally run off the planet. Munroe calculates that the escape velocity – the speed needed to break free from the planet's gravitational pull – would be only about 5 meters per second. That's slower than a sprint for most people.

What's more, the direction of your run wouldn't matter much. As long as you're not running directly towards the planet's center, you'd escape its gravity once you surpass this velocity. You could run off horizontally or even use a ramp to jump off the planet.

Orbiting Your Own World

If you didn't quite reach escape velocity, you might find yourself in orbit around the little planet. The gravitational pull would be too weak to bring you back to the surface, but strong enough to keep you circling the tiny world.

This imaginative exploration of life on The Little Prince's planet not only entertains but also helps us better understand the principles of gravity and orbital mechanics. It's a perfect example of how Munroe uses absurd scenarios to illuminate real scientific concepts.

Printing Wikipedia: A Costly Endeavor

In the digital age, we often take for granted the vast amount of information available at our fingertips. Munroe tackles the question of what it would take to create a live-updating paper version of the English Wikipedia, revealing some surprising insights about the scale of online information and the practical challenges of print media.

The Printing Challenge

At first glance, you might assume that keeping up with Wikipedia's constant updates would require an enormous number of printers. However, Munroe's calculations show that it would only take six printers to stay current with the 125,000 to 150,000 daily edits on Wikipedia.

Assuming each edit requires reprinting one page (a simplification that balances out larger edits with reverts that don't need reprinting), and given that a good inkjet printer can produce about 15 pages per minute, six printers running continuously could match the pace of Wikipedia's updates.

The True Cost

While the number of printers needed is surprisingly low, Munroe reveals that the real challenge lies in the cost. The electricity to run the printers would be relatively cheap, costing only a few dollars a day. Even the paper cost, at about one cent per page, would amount to around a thousand dollars daily.

The real budget-buster, however, would be ink. Munroe estimates that ink costs would range from 5 cents per page for black-and-white to 30 cents per page for photos. This translates to a staggering $4,000 to $5,000 per day just for ink cartridges.

In total, this project would burn through about half a million dollars in just one or two months. This eye-opening calculation not only highlights the impracticality of printing Wikipedia but also serves as a stark reminder of the efficiency and cost-effectiveness of digital information storage and distribution.

Eradicating the Common Cold: A Cure Worse Than the Disease

Munroe tackles another intriguing hypothetical: Could we eliminate the common cold if everyone on Earth isolated themselves for a few weeks? His answer is yes, but with some significant caveats that make this solution far from practical.

The Science of Cold Eradication

The common cold is primarily caused by rhinoviruses, which typically clear from the body within about ten days. Since these viruses don't seem to transmit between humans and animals, isolating all humans for a period longer than the virus's lifespan could theoretically eradicate it.

However, Munroe points out some complications. People with weakened immune systems can harbor cold viruses for years, meaning they'd need a much longer quarantine period. Additionally, mild infections like the common cold actually help strengthen our immune systems, so completely eliminating them might have unintended negative consequences.

The Practical Challenges

The logistical and economic implications of a global quarantine would be staggering. Munroe calculates that pausing all economic activity worldwide for a few weeks would result in a loss of trillions of dollars, given that the world's annual economic output is around $80 trillion.

Then there's the challenge of actually keeping people apart. If we divided the world's land area evenly, each person would have about 77 meters of space around them – enough to prevent virus transmission, but it would mean many people ending up in inhospitable places like the Sahara desert or Antarctica.

Munroe's conclusion? While this method might work from a biological standpoint, it would likely cause the collapse of civilization – a cure far worse than the disease itself.

This exploration serves as a reminder that simple solutions to complex problems often have far-reaching and unintended consequences. It also highlights the delicate balance of our ecosystem and the sometimes counterintuitive nature of disease prevention.

The Search for Soulmates: A Mathematical Impossibility

In a particularly thought-provoking section, Munroe explores the concept of soulmates from a mathematical perspective. What if each person had only one perfect match in the world? The results are both fascinating and a little disheartening.

The Odds of Meeting Your Soulmate

Munroe starts by considering the likelihood that your soulmate even lives in the same era as you. But even assuming they do, the odds of meeting them are astronomically low.

He estimates that we make eye contact with about 24 new people per day. If 10% of these are potential partners (based on age and other factors), over a 60-year lifespan, we'd encounter about 50,000 potential soulmates.

However, with a global population of 7 billion, even if we narrow it down to preferred age and gender, we're still looking at about 500 million potential soulmates. This means we'd need about 10,000 lifetimes to make eye contact with every possible soulmate!

Societal Implications

Munroe speculates on how society might reorganize itself if we truly believed in this one-soulmate concept. We might develop systems like "SoulMateRoulette," where people spend hours each day on webcams, trying to make eye contact with as many people as possible.

In this scenario, only the wealthy might have enough free time to dedicate to the search, creating a new form of inequality based on the ability to find one's soulmate.

This thought experiment not only provides an interesting perspective on the concept of soulmates but also serves as a reminder of how numbers and probability can shape our understanding of human relationships and social structures.

Human vs. Computer Processing Power: A Complex Comparison

In an age where artificial intelligence is advancing rapidly, Munroe tackles the question of how human processing power compares to that of computers. His findings highlight both the strengths of modern technology and the unique capabilities of the human brain.

Raw Calculation Power

When it comes to pure mathematical calculations, computers far outstrip human capabilities. Munroe estimates that if a person manually performed the calculations a computer chip does, they could execute about one instruction every minute and a half.

Based on this, a mid-range mobile phone processor would be about 70 times faster at calculations than the entire human population combined. A high-end PC processor would be around 1,500 times quicker.

The Human Advantage

However, Munroe is quick to point out that this comparison doesn't accurately reflect human cognitive abilities. Our brains excel at tasks that computers struggle with, such as interpreting complex visual scenes or making intuitive leaps.

In terms of complexity, the human brain is still more sophisticated than even the world's most powerful supercomputers. This highlights the fundamental differences in how humans and computers process information.

A Balanced Perspective

To provide a more balanced comparison, Munroe suggests considering how ineffective computer programs are at simulating human brain activity, just as human brains are inefficient at simulating computer processes.

By averaging the pencil-and-paper calculation measure with the complexity measure of human brains, Munroe concludes that our overall performance is roughly on par with computers, albeit in very different ways.

This exploration serves as a reminder of the unique strengths of both human and artificial intelligence, suggesting that the future may lie in combining these complementary capabilities rather than pitting them against each other.

The SAT Guessing Game: An Exercise in Probability

Munroe turns his attention to standardized testing, specifically the SAT, to explore an intriguing question: What if every test-taker guessed on every multiple-choice question? How many perfect scores would we see?

The Astronomical Odds

The 2014 SAT had 158 multiple-choice questions, each with five options. This means the probability of guessing every question correctly is 1 in 5¹⁵⁸, or 1 in 27 quinqua trigintillion – a number so large it's almost impossible to comprehend.

To put this in perspective, Munroe calculates that even if all four million 17-year-olds in the US guessed randomly, the chances of anyone getting a perfect score – or even a perfect score in just one section – are essentially zero.

A Cosmic Perspective

To truly drive home how unlikely a perfect guessed score is, Munroe presents an even more extreme scenario. Imagine each high school student took the SAT a million times every day for five billion years – by which time the Sun will have become a red giant and Earth will be uninhabitable.

Even in this scenario, the likelihood of any student scoring 100% on just the math section through guessing would be about 0.0001%. In other words, it's safe to say we won't see a perfect guessed SAT score before the end of humanity on Earth.

This exploration of probability not only provides an interesting perspective on standardized testing but also helps illustrate the concept of astronomical odds in a relatable way. It's a prime example of how Munroe uses everyday scenarios to explain complex mathematical concepts.

The Future of Facebook: When the Dead Outnumber the Living

In a thought-provoking exploration of social media and demographics, Munroe considers when Facebook might have more profiles of deceased users than living ones. This question touches on issues of digital legacy, population trends, and the longevity of social media platforms.

The Near Future Scenario

Munroe estimates that by 2013, there were probably between 10 to 20 million Facebook profiles belonging to people who had passed away. In the US alone, approximately 290,000 Facebook users likely died in 2013.

If Facebook's growth slows and it starts losing market share in the near future, Munroe calculates that dead profiles could outnumber living ones as early as the 2060s.

The Long-Term Scenario

However, if Facebook manages to maintain its dominance and continues to attract new users across generations, this crossover point might not occur until around 2130.

The Reality Check

Munroe acknowledges that the latter scenario seems unlikely given the rapidly changing nature of the internet and social media. He points to the fate of MySpace as an example of how quickly digital platforms can rise and fall.

This exploration not only provides an interesting thought experiment but also raises important questions about digital legacy and the long-term implications of our online presence. It serves as a reminder of the impermanence of digital platforms and the need to consider what happens to our online identities after we're gone.

Final Thoughts: The Value of Absurd Questions

Throughout "What If?", Randall Munroe demonstrates the surprising insights and entertainment value that can be found in exploring seemingly ridiculous questions. By applying rigorous scientific analysis to these absurd scenarios, he not only provides fascinating answers but also illuminates complex scientific concepts in accessible and engaging ways.

From the unexpected benefits of a sunless world to the mind-boggling improbability of guessing a perfect SAT score, each exploration offers a unique perspective on the world around us. These thought experiments challenge us to think critically, question our assumptions, and appreciate the complexity of the universe we inhabit.

Moreover, Munroe's approach serves as a reminder of the importance of curiosity and the value of asking questions – even (or especially) when they seem silly or impossible. By entertaining these far-fetched scenarios, we can gain new insights into real-world problems and develop a deeper understanding of scientific principles.

The book also highlights the power of interdisciplinary thinking. By combining knowledge from various fields – physics, biology, computer science, economics, and more – Munroe is able to tackle complex questions from multiple angles, often revealing unexpected connections and insights.

Perhaps most importantly, "What If?" demonstrates that science and humor are not mutually exclusive. Munroe's witty writing style and clever illustrations make complex scientific concepts accessible and enjoyable, potentially inspiring readers to further explore the world of science and mathematics.

In conclusion, "What If?" is more than just a collection of amusing thought experiments. It's a celebration of human curiosity, a showcase of the power of scientific thinking, and a reminder that even the most absurd questions can lead to valuable insights. By encouraging readers to think critically and imaginatively about the world around them, Munroe invites us all to embrace our inner scientists and never stop asking "What if?"

As we close this journey through Munroe's imaginative scenarios, we're left with a renewed appreciation for the complexity and wonder of our universe. We're reminded that there's always more to learn, more to question, and more to discover – if only we're willing to ask the right questions, no matter how absurd they might seem at first glance.

So the next time you find yourself pondering an impossible scenario or a seemingly silly question, don't dismiss it. Instead, take a page from Randall Munroe's book and see where that question might lead you. You might be surprised by what you learn along the way.

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