What If?: Serious Scientific Answers to Absurd Hypothetical Questions was published in 2014 and was written by Randall Munroe, a former NASA roboticist. An entertaining, interesting book, it is a fantastic treat for people of all ages thanks to the hilarious language used, the drawings (mostly stick-figures), and the formatting of the questions and answers.
The back of the book provides the reader with a variety of facts, including: if humans could digest cellulose, the book itself would provide them with 2,300 calories, the fact that the book can’t prevent bullets from piercing your body (buy more as safety gear!), the utter uselessness of using the book as a projectile weapon, and the contents (Monroe details that the book includes both words and visuals). The format of this summary will be composed of a list of questions and answers.
Q - pg. 1: “What would happen if the Earth and all terrestrial objects suddenly stopped spinning, but the atmosphere retained its velocity?”
A: Almost everyone on the surface will be killed by extremely fast winds: the only survivors will be those living in underground bunkers and subterranean shopping malls. The sun would take a full year to rise and set from the vantage point of one corner of the world: one side of Earth will be baked by the hot temperature, while the opposite side will be freezing. However, the moon will cause the Earth to start spinning again after some time: its gravity will bring it closer to Earth and make it move along with it, bringing everything back to some semblance of normalcy.
Q - pg. 7: “What would happen if you tried to hit a baseball pitched at 90 percent the speed of light?”
A: The baseball will move so quickly that the heat will cause it to disintegrate rapidly. Physics mandates that the baseball’s energy will create the virtual equivalent of a nuclear bomb, killing the pitcher, the batter, and utterly destroying the surrounding area. Munroe details that basically everything within a mile of the ball will be destroyed. As for the baseball diamond, it will be a crater featuring a hole a few hundred feet deep.
Q - pg. 10: “What if I took a swim in a typical spent nuclear fuel pool? Would I need to dive to actually experience a fatal amount of radiation? How long could I stay safely at the surface?”
A: If the nuclear fuel is located at the bottom of the pool, you can safely swim as long as you remain on the surface. However, if you go down to the storage casks and get reasonably close to it, you can suffer severe radiation poisoning by staying there for mere minutes. Munroe details that if you touch the cask, you will probably die.
Q - pg. 15: “I assume when you travel back in time you end up at the same spot on the Earth’s surface. At least, that’s how it worked in the Back to the Future movies. If so, what would it be like if you traveled back in time, starting in Times Square, New York, 1000 years? 10,000 years? 100,000 years? 1,000,000 years? 1,000,000,000 years? What about forward in time 1,000,000 years?”
A: 1,000 years ago, the Lenape (a confederation of American Indian tribes) lived at where Manhattan stood. 10,000 years ago, the Ice Age still remained, so you would probably see stray icebergs, kettlehole ponds (holes in the ground filled with water), and glacial erratics (boulder dropped by ice sheets). 100,000 years ago, the landscape would be jagged and would be relatively dangerous due to carnivorous animals. 1,000,000 years ago, there would be a large number of predators which would love to eat you. 1,000,000,000 years ago, you would find yourself on Rodinia, the supercontinent which preceded Pangea. 1,000,000 years in the future, there is no telling what will happen. Munroe writes that Homo Sapiens will go extinct eventually like all other animals: there’s no telling how we will go out. Munroe recognizes climate change as an issue and says that while it will delay the next ice age, the cycle probably wouldn’t end. In the far future, the Sun will devour the Earth, consuming it completely and leaving no traces behind.
Q - pg. 23: “What if everyone actually had only one soul mate, a random person somewhere in the world?”
A: If this is true, the chance of you finding your soulmate would be close to 0. That is, even if you have 500,000,000 soul mates, you would only find true love in roughly one out of 10,000 lifetimes. Well, you know what people always say: fake it to make it!
Q - pg. 27: “If every person on Earth aimed a laser pointer at the Moon at the same time, would it change color?”
A: If you used regular (5mw - 5 milliwatts) laser pointers, there would be no effect. If human civilization used $2 trillion to buy 1-watt green lasers for every human being, there will still be no effect. If we use nightsuns (with lenses, each can produce 50,000 lumens) there will be a slight change in the moon. If we use IMAX projectors (30,000 watts), the moon will become visible only slightly. Munroe then states that the Luxor Hotel in Las Vegas has the most powerful spotlight on Earth: if everyone uses it, the Moon will become substantially more visible. If people used megawatt lasers (Boeing YAL-1), originally designed by the Department of Defense to destroy incoming missiles, the moon would be much more visible. If people went so far to construct 50 trillion of these megawatt lasers (using up all of Earth’s oil reserves in two minutes), the Moon will shine as brightly as the sun. Finally, if people utilized 500-Terawatt N.I.F. lasers, the particles emitted by them will make the moon leave our orbit and become its own dwarf-planet.
Q - pg. 35: “What would happen if you made a periodic table out of cube-shaped bricks, where each brick was made of the corresponding element?”
A: If this is achieved, the constructed periodic table will self-destruct due to the numerous hazardous and flammable chemicals placed next to each other, not to mention that some chemicals like technetium and arsenic (both fully capable of killing a human) will be very dangerous to manage. The periodic table, like the previously mentioned baseball traveling at 90% the speed of light, will explode in a way akin to a nuclear bomb that would cause massive damage. Munroe details that while the explosion will immediately kill a large number of people, the radiation poisoning afterward would be sheerly horrendous: “The fallout wouldn’t be normal, everyday radioactive fallout - it would be like a nuclear bomb that kept exploding. The debris would spread around the world, releasing thousands of times more radioactivity than the Chernobyl disaster. Entire regions would be devastated; the cleanup would stretch on for centuries” (42).
Q - pg. 43: “What would happen if everyone on Earth stood as close to each other as they could and jumped, everyone landing on the ground at the same instant?”
A: There will be an initial impact, but it will be insignificant in nature: Earth outweighs humans by ten trillion. Therefore, it is not affected at all by the jump. Munroe himself describes that “A slight pulse of pressure spreads through the North American continental crust and dissipates with little effect. The sound of all those feet hitting the ground creates a loud, drawn-out roar lasting many seconds” (44). After the mass jumping, people try to go back to their respective homes. However, the population density and concentration of human beings cause chaos, and people fight over resources as they try to leave. In just a few weeks, billions are dead (though humans continue to exist), and Earth continues its behavior unaffected and indifferent.
Q - pg. 47: “What would happen if you were to gather a mole (unit of measurement) of moles (the small furry critter) in one place?
A: The numerical definition of a mole involves: 602,214,129,000,000,000,000,000. This is helpfully abbreviated into the following expression: 6.022 · 1023. If that many moles are present on Earth and are together, they will quickly die from suffocation and the pressure of their collective weight. Their mass would be so significant that most life on Earth will actually go extinct: there are so many moles that they will reach up almost to space (completely dwarfing Mt. Everest in the process). If the moles were gathered together in space, their size would be larger than the moon, and when the moles deteriorate and decay, the planet will burst into pieces. Munroe graphically describes, “Plumes of hot meat and bubbles of trapped gases like methane-along with the air from the lungs of the deceased moles-would periodically rise through the mole crust and erupt volcanically from the surface, a geyser of death blasting mole bodies free of the planet” (51). The planet will eventually reach an equilibrium, though it would probably heat Earth up in the process.
Q - pg. 52: “What would happen if a hair dryer with continuous power were turned on and put in an airtight 1 times 1 times 1-meter box?”
A: When the hairdryer reaches 60°C (140°F), it will be warmer than the body temperature of a regular human. When it reaches 200°C (475°F), it could serve as a skillet. When it goes to 600°C, it will cause the box to turn red. When it reaches 1300°C, the box will reach the temperature of lava. Later, as the notch continues to be turned up, more energy will be produced (it is assumed by Monroe in this situation that the box is indestructible: if it isn’t, it would have collapsed entirely long before the end is reached). The hairdryer, upon reaching 1.875 terawatts of output, would release enough energy every second to make people believe that a house-sized quantity of TNT was being blown up. Eventually, the box and the hair dryer will contain so much energy that it will leave Earth into the atmosphere, destroying a large amount of land and organisms in the process.
Q - pg. 61: “If every human somehow simply disappeared from the face of the Earth, how long would it be before the last artificial light source would go out?”
A: While most light sources like diesel generators, geothermal plants, wind turbines, hydroelectric dams, batteries, and nuclear reactors would quickly go out of business relatively quickly, space probes could function for quite some time. Machines that utilize solar power will survive far longer than many of the options listed before, and the last remnant of our use of electricity will be radiation: “Some of our radioactive waste products, such as cesium-137, are melted and mixed with glass, then cooled into a solid block that can be wrapped in more shielding so they can be safely transported and stored” (67). Since Cesium-137 has a half-life of thirty years, it will take centuries for it to stop emitting light.
Q - pg. 68: “Is it possible to build a jetpack using downward firing machine guns?”
A: Most guns would fail at this task, seeing that they either lack the magnitude of force required or hold too few rounds to sustain the pressure. Regardless, there is one gun that would be great as a makeshift jetpack: the Gryazev-Shipunov GSh-6-30, if harnessed (hypothetically, of course), can give people the acceleration needed to jump mountains. However, the acceleration is currently impossible to maintain for long. As Greg Goebel, a scientist, detailed, “The recoil … still had a tendency to inflict damage on the aircraft. The rate of fire was reduced to 4,000 rounds a minute but it didn't help much. Landing lights almost always broke after firing … Firing more than about 30 rounds in a burst was asking for trouble from overheating” (72).
Q - pg. 73: “If you suddenly began rising steadily at 1 foot per second, how exactly would you die? Would you freeze or suffocate first? Or something else?”
A: If you were to begin rising in the prescribed fashion, you will quickly be unreachable: after a mere 25 minutes you will be at the top of the Empire State Building. Two hours after the beginning of the ascension, you have frostbite to worry about, as air pressure has substantially decreased. After a while, the air pressure would continue to decrease and the temperature will continue to plummet: even if you don’t perish from the lack of oxygen, hypothermia will eventually finish you off. If you’re still alive after five hours, you will reach the appropriately named “Death Zone.” This zone is 8,000 meters above the ground, and the oxygen levels here are too low to sustain life: said person will suffer from confusion, clumsiness, nausea, and dizziness. They will then die around the seven-hour mark: most people wouldn’t make it to eight. Munroe interestingly writes, “And two million years later, your frozen body, still moving along steadily at a foot per second, would pass through the heliopause into interstellar space … It’s true that your hypothetical foot-per-second trip would be cold, unpleasant, and rapidly fatal. But when the Sun becomes a red giant in four billion years and consumes the Earth, you and Clyde would be the only ones to escape” (76). It should be noted that “Clyde” refers to Clyde Tombaugh, an astronomer who, upon his death, had his remains placed on the spacecraft named New Horizons which is going to go past Pluto and leave our solar system.
Q - pg. 78: “How long could a nuclear submarine last in orbit?”
A: The nuclear submarine isn’t the thing to be worried about: the people are. To be specific, it will rapidly decelerate and fall apart: the submarine lacks the proper materials (ex. heat-dissipating ablative tiles) to properly function as a satellite that is maneuverable by Homo Sapiens.
Q - pg. 83: “If my printer could literally print out money, would it have that big an effect on the world?”
A: No. You can fit four bills on a standard piece of paper. That means $400 printed every minute. In total, that adds up to $200 million every year. However, it should be noted that there are 7.8 billion $100 bills in circulation. The lifetime of a standard $100 bill is 90 months or 7.5 years. Through that calculation, a billion are produced a year to deal with $100 bills which are phased out. Of course, two million extra $100 dollar bills are quite insignificant compared to one billion.
Q - pg. 84: “What would happen if you set off a nuclear bomb in the eye of a hurricane? Would the storm cell be immediately vaporized?”
A: No. The National Oceanic and Atmospheric Administration, which is in control of the National Hurricane Center, have stated themselves that doing so is foolhardy. Munroe acknowledges that it makes him pleased that “an arm of the US government has, in some official capacity, issued an opinion on the subject of firing nuclear missiles at hurricanes” (84).
Q - pg. 84: “If everyone put little turbine generators on the downspouts of their houses and businesses, how much power would we generate? Would we ever generate enough power to offset the cost of the generators?”
A: This idea is highly infeasible: Munroe calculates that if the generator costs an average of $100, it will take those living in the rainiest area of the US (Ketchikan, Alaska) almost a century to pay the cost back.
Q - pg. 85: “Using only pronounceable letter combinations, how long would names have to be to give each star in the universe a unique one-word name?”
A: Since there are some 300,000,000,000,000,000,000,000 stars in the universe, the name would be as long as the previously given number.
Q - pg. 86: “I bike to class sometimes. It’s annoying biking in the wintertime, because it’s so cold How fast would I have to bike for my skin to warm up the way a spacecraft heats up during reentry?”
A: You have to bike at 200 m/s (meters per second). Munroe then details that if you were capable of moving your bike that quickly (that is, 450 miles per hour), you would probably die in mere seconds from overexertion.
Q - pg. 87: “How much physical space does the Internet take up?”
A: The entire Internet takes up space smaller than an oil tanker due to the recent innovations in spatial management and data.
Q - pg. 88: “What if you strapped C4 to a boomerang? Could this be an effective weapon, or would it be as stupid as it sounds?”
A: While it might be effective if you’re accurate, if you’re not you can potentially injure or kill yourself.
Q - pg. 91: “How dangerous is it, really, to be in a pool during a thunderstorm?”
A: It is quite dangerous, as water is a good conductor of electricity, not to mention there’s nothing serving as a barrier between the surface and the sky.
Q - pg. 92: “What would happen if you were in a boat or a plane that got hit by lightning? Or a submarine?”
A: If you are on a boat without a cabin, you might as well be standing on a golf course (seeing the lack of shelter). If said boat has shelter, you’re in a car (relatively safe). If you’re in a submarine, you should be protected (the submarine shouldn’t be damaged by lightning).
Q - pg. 93: “What if you were changing the light at the top of a radio tower, and lightning struck? Or what if you were doing a backflip? Or standing in a graphite field? Or looking straight up at the bolt?”
A: Munroe doesn’t even really “answer” this question: he draws a comic panel that shows stick figures getting electrocuted and finding themselves in utterly absurd situations.
Q - pg. 93: “What would happen if lightning struck a bullet in midair?”
A: The chance of this happening is close to nil, but if it does happen, the overall picture would still remain the same: bullets commonly have a coat of copper, a good conductor of electricity. Therefore, it will pass through the lightning bolt rapidly, its behavior mostly unaffected.
Q - pg. 94: “What if you were flashing your BIOS during a thunderstorm and you got hit by lightning?”
A: Another cartoon. This one shows a fried computer system.
Q - pg. 96: “How much computing power could we could [the second “could” was included in the text itself] achieve if the entire world population stopped whatever we are doing right now and started doing calculations? How would it compare to a modern-day computer or smartphone?”
A: Computers and humans process information vastly differently. The brains of humans understand the behavior of others by more than sheer logic, while computers are capable of stupendous feats of calculation: in 1994 a single computer already surpassed the mathematical abilities of all humans combined. Needless to say, there is no competition when it comes to tasks like doing math. Munroe details that comparing humans and computers are ludicrous, for the anatomy of both are completely different: while machines commonly rely on computer chips and wires, humans utilize neurons and memories.
Q - pg. 102: “If an asteroid was very small but supermassive, could you really live on it like the Little Prince?”
A: It could be possible, but the amount of movement allowed has to be restricted.
Q - pg. 107: “From what height would you need to drop a steak for it to be cooked when it hit the ground?”
A: While it is possible for a steak to be charred from falling at a rapid speed, it will be mostly impossible for the steak to be fully cooked: the amount of time it needs to be in the air is too long for most possibilities. Munroe admits that even “if the temperature is high enough or the burn time long enough, the steak will slowly disintegrate as the outer layer is repeatedly charred and blasted off. If most of the steak makes it to the ground, the inside will still be raw” (111). Indeed, there is no good solution to this question.
Q - pg. 112: “How hard would a puck have to be shot to be able to knock the goalie himself backward into the net?”
A: This is technically impossible: even if the goalie launches the puck with great force, the puck, at the end of the day, is small and lightweight: its weight is inconsequential compared to a Homo Sapiens.
Q - pg. 114: “If everyone on the planet stayed away from each other for a couple of weeks, wouldn’t the common cold be wiped out?”
A: While it is supposedly possible for people to stay away from each other for a few weeks (though this will tax a very large amount of resources; people will also have to stay 77 meters apart), this may not be worth it in the end: the common cold bolsters the immune system of the survivors. If the immune system is not occasionally used, it will be unprepared for disease when they do come. While it is possible for most who have the flu to recover during the quarantine, it is virtually guaranteed that a few people with weakened and compromised immune systems will still remain sick after the quarantine. As society gathers back together, cases of the flu will only explode, rendering the whole project virtually useless.
Q - pg. 119: “What if a glass of water was, all of a sudden, literally half empty?”
A: If a glass was literally half-empty, that would mean the existence of a vacuum. The vacuum would cause the glass to float into the air before shattering it. As Munroe describes: “the detached upper portion of the glass continues to rise. After half a second, the observers, hearing a pop, began to flinch. Their heads lift involuntarily to follow the rising movement of the glass. The glass has just enough speed to bang against the ceiling, breaking into fragments … which, their momentum now spent, return to the table” (124). Munroe writes that the lesson to be learned here is that if the optimist reports the glass is half full and the pessimist says that it is half empty, the physicist (if present) should try to find cover to spare themselves from potential injury.
Q - pg. 126: “Let’s assume there’s life on the nearest habitable exoplanet and that they have technology comparable to ours. If they looked at our star right now, what would they see?”
A: While we do emit a large number of radio waves, space is mostly empty, so the radio waves, even if they reach the aliens, will take a very long time. Furthermore, when it comes to other clues like visible light, the clearest signals might not even come from humans: “if you watched the Earth for long enough, you could figure out a lot about our atmosphere from the reflectivity. You could probably figure out what our water cycle looked like, and our oxygen-rich atmosphere would give you a hint that something weird was going on. So in the end, the clearest signal from Earth might not be from us at all. It might be from the algae that have been terraforming the planet-and altering the signals we send into space-for billions of years” (129).
Q - pg. 131: “This may be a bit gruesome, but … if someone’s DNA suddenly vanished, how long would that person last?”
A: Not very long. By losing your DNA, you lose roughly one-third of your weight. A fungus known as the destroying angel (scientific name is the Amanita bisporigera) has the potential to damage DNA: it is severely toxic and horrendously dangerous. That is, while it does appear like a regular mushroom, upon being eaten, it quickly causes irreversible damage that is fatal: early symptoms include vomiting, diarrhea, and abdominal pain. The destroying angel has a chemical, amatoxin, that basically cripples DNA and their cooperation with cells by binding to an enzyme whose sole purpose is to facilitate cooperation between DNA and cells. Munroe writes that those who eat the destroying angel generally die from liver or kidney failure. While some people do survive by getting a liver transplant, many die: “The frightening thing about Amanita poisoning is the ‘walking ghost’ phase-the period where you seem to be fine (or getting better), but your cells are accumulating irreversible and lethal damage. This pattern is typical of DNA damage” (134). Munroe states that chemotherapy and radiation also damage DNA: chemotherapy is akin to an instrument which indiscriminately does damage while radiation could kill people when taken in large doses (mostly by accident, of course): “In cases of severe radiation poisoning, the immune system collapse is the primary cause of death. Without a supply of white blood cells, the body can’t fight off infections, and ordinary bacteria can get into the body and run wild” (135). Especially severe radiation poisoning can kill people even quicker by causing intense cerebral hemorrhaging: physical barriers that help maintain the operation of the brain are dissolved. To summarize, losing DNA causes intense physical symptoms which cause a large portion of suffering: you are basically guaranteed to be dead in days due to bacterial infection or complete organ failure.
Q - pg. 137: “What would happen if you tried to fly a normal Earth airplane above different solar system bodies?”
A: It really depends on which planet you’re talking about. If you do it for the sun, it would be immediately vaporized. As of the current moment, flying a normal Earth airplane above Mars is impossible (though this may not remain so in the future). Munroe details that Mars has no atmosphere, hence why it is so difficult for aerial travel. For Venus, the plane would be capable of flying, though it would catch on fire due to the extremely high temperature of Venus, eventually causing it to crash. However, if you fly above the clouds on Venus, you can hypothetically remain there for quite some time, though the pilot would require an oxygen mask and protective equipment to prevent them from dying of the ever-present sulfuric acid. As for Jupiter, it’s impossible: the gravity is too strong. To be specific, “The power needed to maintain level flight under Jupiter’s gravity is three times greater than that on Earth” (140). Conversely, trying to fly an airplane on Saturn is easier than trying to do so on Jupiter due to the weaker gravity. Uranus is a great candidate for airplane travel: however, there may not be much to do there, seeing it is largely featureless. Neptune is in a similar situation to Uranus. Flying on Titan is a better place for flying than Earth, seeing that “Its atmosphere is thick but its gravity is light … surface pressure only 50 percent higher than Earth’s with air four times as dense. Its gravity-lower than that of the Moon-means that flying is easy. Our Cessna could get into the air under pedal power. In fact, humans on Titan could fly by muscle power. A human in a hang glider could comfortably take off and cruise around powered by organized swim-flipper boots-or even take off by flapping artificial wings” (141). Indeed, flying on Titan is extremely easy due to the air density and gravity, so easy that doing so is just like walking. Munroe provides the readers with a caveat: Titan is very cold, so if flight is attempted for even a few minutes, the person will come crashing back down to the ground once their wings are frozen.
Q - pg. 143: “How much Force power can Yoda output?”
A: The most impressive feat Yoda did in the Star Wars original trilogy was when he lifted Luke’s X-Wing from a swamp using the Force in Dagobah. Through mathematics, Munroe calculates that Yoda has the equivalent of 25 horsepower, making him worth $2 an hour by modern electrical standards. Following that logic, one hundred million Yodas would be required to manage all the world’s electricity at the time of the book’s publication (that is, 2 terawatts).
Q - pg. 146: “Which US state is actually flown over the most?”
A: Virginia. Atlanta, Georgia has the Hartsfield-Jackson Atlanta International Airport, which is the busiest in the entire world. There is also the Toronto Pearson International Airport, which sees more flights than the JFK and LaGuardia airports in New York combined. Munroe then presents a succession of facts, writing that “The state with the highest ratio of flights-over-to-flights-to, however, is a surprise: Delaware. This is because there are no airports in Delaware. Furthermore, the least flown-over state is Hawaii, seeing that it's a series of small islands. The most flown-under state (that is, a state which sees the most amount of flights on the opposite side of the world) is Hawaii, as the US is on the other side of the globe.
Q - pg. 150: “What if I jumped out of an airplane with a couple of tanks of helium and one huge, uninflated balloon? Then, while falling, I release the helium and fill the balloon. How long of a fall would I need in order for the balloon to slow me enough that I could land safely?”
A: Munroe was banned from a mathematical society for trying to figure out the answer to this question.
Q - pg. 153: “Is there enough energy to move the entire current human population off-planet?”
A: No. While it may be somewhat simple to send one person into space, sending all of humanity there requires more energy than is currently available. Munroe writes that if every person requires 4 gigajoules to go to another planet, it's possible (however, 4 gigajoules is the bare minimum). Furthermore, if humans tried to leave via rockets, that plan would require trillions of tons of fuel. Munroe details that his question was actually attempted before, seeing how Freeman Dyson, a famed physicist, started Project Orion (featuring nuclear pulse propulsion: you basically ride the wave of a nuclear bomb in a well-designed spaceship) in the 1960s: however, it was closed before any prototypes were actually built. Munroe writes that for those who believed in the possibility of the project succeeding, the cancelation of the project was extremely disappointing. On the other hand, those against it, who frequently believed it might destroy humanity, were glad. To summarize, “So the answer is that while sending one person into space is easy, getting all of us there would tax our resources to the limit and possibly destroy the planet. It’s a small step for a man, but a giant leap for mankind” (156).
Q - pg. 158: “I read about some researchers who were trying to produce sperm from bone marrow stem cells. If a woman were to have sperm cells made from her own stem cells and impregnate herself, what would be her relationship to her daughter?”
A: She’s still the mom: although asexual complex organisms are somewhat rare (inbreeding could cause a large number of problems - think of royal inbreeding and hemophilia, not to mention sexual reproduction allows for diversity), they still do exist (ex. Tremblay’s Salamanders are salamanders that reproduce only by self-fertilizing: furthermore, they are entirely female, with three, not two, genomes).
Q - pg. 168: “How high can a human throw something?”
A: Aroldis Chapman, a professional baseball player (he holds the world record for the fastest pitch/105 mph) could, if using a golf ball, throw it the height of sixteen adult giraffes. Munroe humorously points out that this record can be easily broken by anyone: simply buy a balloon and let go of it while it’s still full of helium.
Q - pg. 174: “How close would you have to be to a supernova to get a lethal dose of neutrino radiation?”
A: Neutrinos are almost always completely harmless: they are particles that barely interact with the world. For instance, right now your hand has a trillion neutrinos from the Sun. As shown in that example, they are completely invisible. While they do interact with material objects, that’s very rare: the first time a neutrino interaction occurs to a human is around the age of ten. Therefore, don’t count on neutrino radiation to kill anyone anytime soon. However, it is still possible: radiation expert Andrew Karam said that when some supernovae happen, neutrinos are indeed released: 1057 of them, which is potentially fatal. Munroe writes of the sheer scope of supernovae: “The idea of neutrino radiation damage reinforces just how big supernovae are. If you observed a supernova from 1 AU away [astronomical unit - 93 million miles] - and you somehow avoided being incinerated, vaporized, and converted to some type of exotic plasma-even the flood of ghostly neutrinos would be dense enough to kill you” (177).
Q - pg. 179: “How fast can you hit a speed bump while driving and live?”
A: By calculating force, a car traveling in the range of 150-300 mph will crash before even meeting the speed bump. Even if the car is somehow prevented from toppling over entirely, the force of the wind would completely rip apart the car. Furthermore, “At higher speeds, the car itself would be disassembled, and might even burn up like a spacecraft reentering the atmosphere” (182).
Q - pg. 183: “If two immortal people were placed on opposite sides of an uninhabited Earthlike planet, how long would it take them to find each other? 100,000 years? 1,000,000 years? 100,000,000,000 years?”
A: Surprisingly, the answer isn’t too long: 3,000 years. That is, it would take two people 3,000 years to find each other if they walk for twelve hours a day and spot each other when the other is a kilometer or less away. Of course, some locations make seeing others difficult, such as jungles, forests, and shopping malls (the best example of a real-life labyrinth). Munroe writes that when it comes to finding the other person as quickly as possible, you would do well to follow the coastline, to leave a trail of rocks, and to move quickly.
Q - pg. 188: Munroe responds to a series of three questions that had to deal with spaceships and speed on pg. 187. He writes that the problem with space travel is not with leaving the atmosphere but with staying in space: gravity in Earth’s orbit is almost as powerful as the gravity present on the surface. Furthermore, he writes that “Reaching orbital speed takes much more fuel than reaching orbital height”; the spacecraft has to move at 8 km/s to succeed in this task (189). 8 km/s is extremely fast (Munroe writes that it’s “blisteringly fast”): a spaceship moving at that speed can travel around Earth in a mere 90 minutes.
Q - pg. 192: “When-if ever-will the bandwidth of the Internet surpass that of FedEx?”
A: Never. Internet microchips can easily fit within a FedEx box.
Q - pg. 195: “What place on Earth would allow you to free-fall the longest by jumping off it? What about using a squirrel suit?”
A: If you want to drop vertically for the longest amount of time, go to Mount Thor, which is located in Canada. Using a squirrel suit will slow down the fall; however, like everything else discussed in the book, caution is strongly advised.
Q - pg. 200: “In the movie 300 they shoot arrows up into the sky and they seemingly blot out the sun. Is this possible, and how many arrows would it take?”
A: Munroe writes that if you really want to block out the sun, do it at dawn, seeing that the sun at that moment is still limited in scope. Once that is dealt with, have a large number of archers in highly organized rows shoot at the same time in the north direction: the arrows will aid each other (if they don’t pierce each other, of course) seeing that they cast shadows over each other. Munroe notes that this is highly unadvised for war: while it might look intimidating and cool, the arrows, if launched to fulfill this process, will probably leave the enemy unscathed.
Q - pg. 204: “How quickly would the oceans drain if a circular portal 10 meters in radius leading into space were created at the bottom of Challenger Deep, the deepest spot in the ocean? How would the Earth change as the water was being drained?”
A: If there is only a single hole, it will take hundreds of thousands of years for the ocean to completely drain: most of the Earth is covered with ocean, so there is obviously an extremely massive amount of water present on the planet. If multiple portals were opened at once, much land would be exposed over the years, causing existing nations to expand. This would cause a mass extinction event (a dramatic decrease in water would uproot the biosphere): if humans do survive, they will find themselves on an Earth composed mostly of land.
Q - pg. 210: “Supposing you did drain the oceans, and dumped the water on top of the Curiosity rover, how would Mars change as the water accumulated?”
A: Since the Curiosity is currently sitting in the Gale Crater, a large depression in the ground, the water, when dumped, will cause it to rapidly become a lake. After that, the Curiosity will be completely buried underwater. The water would spread out across Mars, covering most of its surface. Only a few landmarks would still remain above water (ex. volcanoes like Olympus Mons, a mountain around two-and-a-half-times the height of Mt. Everest). The oceans wouldn’t remain as a liquid for long due to the freezing temperature of Mars, and will subsequently become permafrost and ice.
Q - pg. 217: “How many unique English tweets are possible? How long would it take for the population of the world to read them all out loud?”
A: Munroe begins his answer with a wondrous and beautiful story. It goes as follows, and it was written by Hendrik Willem Van Loon: “High up in the North in the land called Svithjod, there stands a rock. It is a hundred miles high and a hundred miles wide. Once every thousand years a little bird comes to this rock to sharpen its beak. When the rock has thus been worn away, then a single day of eternity will have gone by” (217). Indeed, the previous example clearly illustrates the enormity of time and the utter unimportance of humankind (which is somewhat comforting: even if things do go terribly wrong, they truly don’t matter at all in the long-run). Anyhow, back to the question, each tweet could be up to 140 characters long. There are multiple options besides words, which means that there are 2 times 1046 meaningful tweets. It will take a single person 1047 seconds to read all of them. That is, it will take up so much time that it will take up ten thousand eternal years (like a human year, an eternal year is 365 days, and each day sees a mountain being worn down over untold years). In Munroe’s own words, if you read all the tweets, you’ll have “enough time to watch all of human history unfold, from the invention of writing to the present, with each day lasting as long as it takes for the bird to wear down a mountain. While 140 characters may not seem like a lot, we will never run out of things to say.” Finally, to read all the tweets will require countless more years than those in Earth’s history (4.5 billion so far).
Q - pg. 222: “How many Lego bricks would it take to build a bridge capable of carrying traffic from London to New York? Have that many Lego bricks been manufactured?”
A: That will require 350 million legos. If a bridge is to be constructed, the best option is a 2 · 4 lego. In total, more than 400 billion Legos have been produced over the years, and 1 out of every 50-100 pieces is a 2 · 4 rectangular brick. Therefore, there are 5-10 billion 2 · 4 bricks in existence, much more than what is required to build a bridge. However, there are other things to worry about when it comes to constructing the bridge: ships, the movement of cars upon the legos, storms, waves, wind, and the sheer cost of implementing this project. Munroe details that the cheapest potential Lego bridge would cost $5 trillion, and that “The total value of the London real estate market is $2.1 trillion, and transatlantic shipping rates are about $30 per ton. This means that for less than the cost of our bridge, we could buy all the property in London and ship it, piece by piece, to New York. Then we could reassemble it on a new island in New York Harbor, and connect the two cities with a much simpler Lego bridge” (227).
Q - pg. 228: “What is the longest possible sunset you can experience while driving, assuming we are obeying the speed limit and driving our paved roads?”
A: The longest sunset is 95 minutes long; geography is key, as can be expected.
Q - pg. 229: “If you call a random phone number and say ‘God bless you,’ what are the chances that the person who answers just sneezed?”
A: Statistically, Munroe estimates that it is 1 in 40,000. Also, the chance that you blessed someone who just committed murder is 1 in 1,000,000,000 (a fantastic caveat to discourage such behavior). The chance of you calling someone who just published an article on sneezing is 1 in 10,000,000. Furthermore, the chance that you called someone who had been killed by lightning thirty seconds prior is 1 in 10,000,000,000,000 (around 60 people are killed by lightning in the US annually). Munroe gives one last factoid: if two of five people go around calling people to give them blessings, “there’s about a 10,000,000,000,000 chance that two of them will simultaneously call each other. At this point, probability will give up, and they’ll both be struck by lightning” (235).
Q - pg. 237: “How long would it take for people to notice their weight gain if the mean radius of the world expanded by 1cm every second? (Assuming the average composition of rock were maintained.)”
A: In one year alone, gravity would be strengthened by 5 percent. After five years, gravity would be strengthened by 25 percent. This would cause most of humanity’s infrastructure and creations to collapse, as the ground below them would have expanded, disrupting their base. Despite this terrible effect, most skyscrapers would still remain erect. After ten years, humanity would be in serious travel: gravity would be strengthened by 50 percent. This will cause air to become harder to breathe. After 40 years, humanity is in dire circumstances: gravity’s strength would be tripled. People could barely walk: most would be rendered almost completely immobile. Crops would be left stunted due to not being able to maintain their vertical shape. Natural disasters akin to landslides would occur, and Earth would become hotter. After 100 years, humans would go completely extinct: gravity would become so powerful that blood would be unable to circulate in our bodies, not to mention that we would be completely paralyzed. The only survivors would be small organisms (insects) and sea animals: “Outside of low-pressure domes, the air would become unbreathable for a different reason. At somewhere around 6 atmospheres, even ordinary air becomes toxic. Even if we’d managed to survive all the other problems, by 100 years, we’d be dead from oxygen toxicity” (242). After 300 years, the Earth’s gravity would fracture the moon, turning it into a set of rings. It is possible after some more time for Earth to turn into a black hole.
Q - pg. 244: “Assuming a zero-gravity environment with an atmosphere identical to Earth’s, how long would it take the friction of air to stop an arrow fired from a bow? Would it eventually come to a standstill and hover in midair?”
A: While the arrow will travel much farther than it would’ve, it would slow down very slowly over time. That is, “After a few hours, the arrow would be moving so slowly that it would be barely visible. At this point, assuming the air is relatively still, the air would start acting like honey instead of water. And the arrow would, very gradually, come to a stop … at minimum, it would probably fly several kilometers, and could conceivably go as far as 5 or 10” (247).
Q - pg. 248: “What would happen to the Earth if the Sun suddenly switched off?”
A: If the Sun suddenly went out, there would be: (1) no risk of solar flares (in 1859, an extremely large solar flare caused massive damage to wires - if that was to happen today, there would be trillions of dollars worth of damages), improved satellite service (the Sun won’t interfere with the signal), more accurate astronomy, the stabilization of dust around the Sun, cheaper transportation (people can drive on rivers and oceans which have become ice), better trade (Coordinated Universal Time), safer children (sunlight can harm babies), and safe handling of parsnip (parsnip causes a nasty rash when exposed to sunlight even weeks after initial exposure). However, for all these benefits, there would be one catastrophic price: our crops wouldn’t grow and we would all freeze to death. The entire food chain would collapse as autotrophs die, and humanity would go down with the other species. RIP.
Q - pg. 252: “If you had a printed version of the whole of (say, the English) Wikipedia, how many printers would you need in order to keep up with the changes made to the live version?”
A: You would need 6 printers, seeing that the English Wikipedia receives 125,000-150,000 edits every day (90-100 per minute). While six printers may not sound like many, they will constantly operate: you will have to pay $500,000 per month. To be more specific, electricity and ink would add up to large costs, making printing out Wikipedia a very bad idea.
Q - pg. 255: “When, if ever, will Facebook contain more profiles of dead people than of living ones?”
A: Munroe writes that this will occur either in the 2060s or the 2130s. The potential crossover date for Facebook (when the dead outnumber the living) will probably occur around 2065. Munroe details that death, as a difficult subject, will continue to be acknowledged by humanity, even as our technology improves: “Like every group that came before us, we’re learning how to play those same games on our particular playing field. We’re developing, through sometimes messy trial and error, a net set of social norms for dating, arguing, learning, and growing on the Internet. Sooner or later, we’ll figure out how to mourn” (258).
Q - pg. 259: “When (if ever) did the Sun finally set on the British Empire?”
A: This hasn’t happened yet, seeing how Britain, despite being very small, has many overseas territories even today, such as the Virgin, Falkland, and Pitcairn Islands (the Pitcairn Islands are very infamous: one-third of the adult population have been found guilty of molesting children). However, even if the British Empire continues to hold these islands, a total solar eclipse will eventually happen, seeing the movements of the heavenly spheres - there is nothing that can be done as of the current moment in technological development to prevent this from happening.
Q - pg. 262: “I was absentmindedly stirring a cup of hot tea, when I got to thinking, ‘Aren’t I actually adding kinetic energy into this cup?’ I know that stirring does help to cool down the tea, but what if I were to stir it faster? Would I be able to boil a cup of water by stirring?”
A: You won’t be able to do so, seeing how the energy you add is far from enough to create a drastic temperature change. Furthermore, tea has a large heat capacity, making it even more difficult. As if that’s not enough, there’s also fluid dynamics to think about: turning a spoon very quickly would cause the tea to “cavitate; a vacuum would form along the path of the spoon and stirring would become ineffective. And if you stir hard enough that your tea cavitates, its surface area will increase very rapidly, and it will cool to room temperature in seconds. No matter how hard you stir your tea, it’s not going to get any warmer” (265).
Q - pg. 266: “If all the lightning strikes happening in the world on any given day all happened in the same place at once, what would happen to that place?”
A: If this was to happen, two atomic bombs’ worth of energy would meet the air and ground of the said area; if you were standing there, you’re basically guaranteed to die from electrocution. Furthermore, the energy delivered would be enough “to power a game console and plasma TV for several million years. Or, to put it another way, it could support the US’s electric consumption … for five minutes. The bolt itself wouldn’t be much wider than the center circle of a basketball court, but it would leave a crater the size of the entire court” (268). Also, the air would become high-energy plasma due to the electricity, and the resulting shockwave would be strong enough to tear buildings apart. Munroe tellingly details Catatumbo, a place in Venezuela that has constant lightning storms almost every night: a flash of lightning occurs roughly every two seconds there. If all the energy from the lightning of a single night of thunderstorms in that area alone were to be successfully channeled into a game console and plasma TV, it would provide enough power to run them both for a century.
Q - pg. 270: “What is the farthest one human being has ever been from every other living person? Were they lonely?”
A: There are definitely some good candidates for this question. There are the astronauts on the moon (at the maximum, they were 3585 kilometers from their colleagues), the Polynesians (when they went across the Pacific to isolated islands, it is possible the islands were discovered by only a few people who might’ve been blown off course), and Antarctic explorers (in the beginning of the expeditions, of course). When it comes to loneliness, Munroe notes that the astronauts didn't feel lonely at all: they might’ve been alone, but they didn't feel lonely, as being in space is a truly unique and wholesome experience.
Q - pg. 274: “What if a rainstorm dropped all of its water in a single giant drop?”
A: Said droplet of water would weigh 600 million tons (making it weigh as much as the human species at the time of publication). When the droplet lands on the ground, anyone under it would be crushed to death: the pressure created by the collision of water and land would be greater than the tension at the bottom of the Mariana Trench. The droplet will then spread out, destroying buildings within 20-30 kilometers. As Munroe describes, “The wall of water expands outward kilometer by kilometer, ripping up trees, houses, and topsoil as it goes. The house, porch, and old-timers are obliterated in an instant. Everything within a few kilometers is completely scoured away, leaving a pool of mud atop bedrock … At this distance, areas shielded by mountains or ridges are protected, and the flood begins to flow along natural valleys and waterways. The broader region is largely protected from the effects of the storm, though areas hundreds of kilometers downstream experience flash flooding in the hours after the impact” (277).
Q - pg. 278: “What if everyone who took the SAT guessed on every multiple-choice question? How many perfect scores would there be?”
A: There would be 0: the chance that you guess and get everything right is 1 in 27 quinquatrigintillion, or (1)/(2.7 times 10110). It is more likely for every ex-President and main cast members of Firefly to be struck by lightning on the same day than for you to get a perfect score by mere guessing. The moral of this question is: don’t plan to use guessing as a substitute for studying. Most likely, it won’t turn out well for you.
Q - pg. 280: “If a bullet with the density of a neutron star were fired from a handgun (ignoring the how) at the Earth’s surface, would the Earth be destroyed?”
A: A bullet with the density of a neutron star would weigh as much as the Empire State Building. To begin, neutron stars are the remains of stars after they collapse under their own gravity. Neutron stars are basically less dangerous versions of black holes (if said original star is heavier, it might become a black hole). Therefore, if it is fired at the ground, the bullet with the density of a neutron star would easily puncture the Earth: “far below, the bullet would be crushing and vaporizing the mantle in front of it as it fell. It would blast the material out of the way with powerful shockwaves, leaving a trail of superhot plasma behind it. This would be something never before seen in the history of the universe: an underground shooting star” (282). Eventually, the bullet would stop moving, and the Earth would continue with its regular rotation. If the bullet was to be sat on a pedestal, it would have a strong influence on gravity. The closer you get to it, the more difficult it would be to proceed: from your vantage point, it would appear as if the ground was tilting forward. Once you get very close to the pedestal, your blood would be rushing to your head, putting you in great physiological danger. Munroe details that “Once you get within a few inches, the force on your fingers is overwhelming, and they’re yanked forward-with or without you-and your fingertips actually touch the bullet (probably dislocating your fingers and shoulder). When your fingertip actually comes in contact with the bullet, the pressure in your fingertips become too strong, and your blood breaks through the skin” (285). Your blood would be quickly funneled out of your body, causing you to die almost immediately. The blood would form a bubble around the bullet, creating a bizarre sight.
Q - pg. 290: “What if a Richter magnitude 15 earthquake were to hit America at, let’s say, New York City? What about a Richter 20? 25?”
A: A magnitude 15 earthquake would release 1032 joules of energy and completely alter the geography of the Earth: “To put it another way, the Death Star caused a magnitude 15 earthquake on Alderaan” (290). A magnitude 20 earthquake would be so strong (these quakes occur in a superheavy neutron star) that it would release the same amount of energy as the simultaneous detonation of hydrogen bombs that have the same volume as the Earth. Munroe then details that the Richter scale does have negative numbers, and said negative phenomena are not catastrophic at all: they are completely inconsequential and ignorable. Munroe happily notes after detailing some of them (up to -15, which is some dust coming to rest on a table) that “Sometimes it’s nice not to destroy the world for a change” (295).
Personal thoughts:
What If?: Serious Answers to Absurd Hypothetical Questions by Randall Munroe is a truly enjoyable and enlightening read, as it has actual science and calculations in response to seldom-asked questions. The illustrations all serve to lighten the mood, and Munroe’s humor is greatly appreciated. I highly recommend What If? to anyone interested in hypothetical situations, science, humor, and stick figures.
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