This chapter chronicles how Einstein’s theories changed what we know about the universe. Bryson states that by the end of the nineteenth century, scientists assumed that they “had pinned down most of the mysteries of the physical world: electricity, magnetism, gases, optics, acoustics, kinetics, and statistical mechanics, to name just a few, all had fallen into order before them” (115). Scientists believed there wasn’t much left that science had to do.

Before Einstein, there was J. Willard Gibbs, a scientist who knew that science still had a lot more to offer. From 1875-78, Gibbs produced a collection of papers that showed how thermodynamics “didn’t apply simply to heat and energy at the sort of large and noisy scale of the steam engine, but was also present and influential at the atomic level of chemical reactions” (117).

There were also Albert Michelson and Edward Morley, who disproved the longstanding belief that luminiferous ether, an imaginary substance that was thought to permeate the universe, was real. Michelson invented a device known as the interferometer, which measured the Earth’s travel time around the Sun. After years of measurements, Michelson found that the “speed of light turned out to be the same in all directions and at all seasons” (119). This proved that Newton’s laws might not apply everywhere in the universe.

There was also the theoretical physicist Max Planck, who came up with quantum theory, which “posited that energy is not a continuous thing like flowing water but comes in individualized packets, which he called quanta” (119). Plank’s ideas laid the foundation for modern physics. He was proceededby Albert Einstein. Einstein, a hobby physicist who was working at a Swiss patent office, produced one of the most brilliant scientific papers of all time, entitled “On the Electrodynamics of Moving Bodies.” With no footnotes, citations, or mention of anyone else’s work, it seemed that Einstein had come up with his conclusions completely on his own.

From this paper, we get the famous equation E=mc^2, where E is energy, m is mass, and c is the speed of light squared. This was groundbreaking because it demonstrated that mass and energy have an equivalence:

“They are two forms of the same thing: energy is liberated matter; matter is energy waiting to happen. Since c^2 (the speed of light times itself) is a truly enormous number, what the equation is really saying is that there is a huge amount—a really huge amount—of energy bound up in every material thing” (122).

Einstein’s theory explained how radiation worked and that the speed of light was constant.

In 1917, Einstein produced another brilliant paper on the idea of relativity. Here, Einstein theorized what happens when light encounters gravity. Bryson states that “In essence, what relativity says is that space and time are not absolute, but relative to both the observer and to the thing being observed, and the faster one moves the more pronounced these effects become” (124). Contrary to intuition, time is a part of space. Time is ever changing, and has shape, with three dimensions known as spacetime. Spacetime, Bryson states, is best visualized as a mattress: imagine a heavy iron ball in the middle of the mattress; the mattress will sag with the weight of the ball. This is essentially the effect that the Sun (the iron ball) has on spacetime (the mattress). If one were to try to roll a smaller ball across spacetime, it will try to go in a straight line according to Newton’s law, but it will inevitably fall into the slope of the sag and roll downward. This is Einstein’s definition of gravity—“a product of the bending of spacetime” (126). In this way, gravity isn’t a force but an effect of spacetime being warped. Yet, the biggest realization to spring from this theory is the idea that the universe must be expanding or contracting.

About the same time that Einstein was devising these theories, an astronomer named VestoSlipher observed a Doppler Shift occurring indistant stars, which essentially means the stars appeared to be moving away from us. However, Slipher didn’t get the recognition for this observation. Instead, Edwin Hubble, regarded as the most outstanding astronomer of the twentieth century, took all the credit. He discovered how old and how big the universe is. By observing “standard candles—stars whose brightness can be reliably calculated and used as benchmarks to measure the brightness (and hence the relative distance) of other stars,” Hubble observed that the universe is quickly and evenly expanding in all directions (130).

Bryson opens this chapter by quoting physicist Richard Freyman, who said that if you had to reduce scientific history to one important statement it would be “All things are made of atoms” (133). Atoms are the focus of this chapter, and Bryson emphasizes how everything a person can see, even the air one breathes, is made of atoms. A molecule (Latin for “little mass,”) is basically two or more atoms working together. Bryson gives the analogy that “Chemists tend to think in terms of molecules rather than elements in much the way that writers tend to think in terms of words and not letters, so it is molecules they count, and these are numerous to say the least” (133). For example, one cubic centimeter of air, roughly the size of a sugar cube, contains 45 billion billion molecules.

Atoms are also tough, and survive almost forever. Bryson states that “Every atom you possess has almost certainly passed through several stars and been part of millions of organisms on its way to becoming you” (134). Basically, Bryson sums up the attributes of atoms by calling them “small, numerous, and practically indestructible,” which has made them difficult to understand, let alone study (135).

English Quaker John Dalton (first introduced in Chapter 7),wrote A New System of Chemical Philosophy, making atoms more understandable. While the idea of atoms wasn’t new, Dalton’s ability to describe the size and character of atoms was revolutionary. He was also the first to give the elements atomic weights. Despite Dalton’s work, many well-known scientists doubted the existence of atoms at all. It wasn’t until Ernest Rutherford came along that atoms were more widely accepted and understood.

Rutherford was the first to discover that “the power inherent in the atom could, if harnessed, make bombs powerful enough to ‘make this old world vanish in smoke’” (138). He was also the first to realize that atoms are mostly empty space with a dense nucleus in the middle. To visualize this, Bryson gives the example that “if an atom were expanded to the size of a cathedral, the nucleus would be only about the size of a fly—but a fly many thousands of times heavier than the cathedral” (141). It was this paradox that initially confused Rutherford, but it was clear that the atom isn’t governed by the same rules as the macro world.

Bryson moves on to Niels Bohr, who puzzled over why wavelengths of hydrogen “produced patterns showing that hydrogen atoms emitted energy at certain wavelengths but not others. It was like someone under surveillance kept turning up at particular locations but was never observed traveling between them” (142). Bohr found the answer in his famous paper, “On the Constitutions of Atoms and Molecules.” The paper explained the idea of a “quantum leap,” which essentially means that an “electron moving between orbits would disappear from one and reappear instantaneously in another without visiting the space between”(143). This theory explained how electrons didn’t crash into the nucleus,along with hydrogen’s strange wavelengths. After these findings, Rutherford went on to discover neutrons, neutralizing particles that prevent the nucleus from exploding. His associate, James Chadwick, proved that neutrons existed.

Bryson also mentions Erwin Shrodinger, who invented wave mechanics, and physicist Werner Heisenberg, who invented a competing theory called matrix mechanics. In 1926, Heisenberg developed a compromise of the two theories, which he called quantum mechanics. At the center of the theory was Heisenberg’s Uncertainty Principle, which states that “the electron is a particle but a particle that can be described in terms of waves” (144). In practice, this means that an electron’s movements are unpredictable, and scientists can only predict the probability of the electron’s movement. Bryson, quoting Dennis Overbye states, “an electron doesn’t exist until it is observed” (144). In other words, an electron must be presumed to be everywhere and nowhere until observed. 

Bryson mentions Schrodinger’s famous thought experiment, in which he places a hypothetical cat in a box with one atom of a radioactive substance attached to a vial of hydrocyanic acid:

“If the particle degraded within an hour, it would trigger a mechanism that would break the vial and poison the cat. If not, the cat would live. But we could not know which was the case, so there was no choice, scientifically, but to regard the cat as 100 percent alive and 100 percent dead at the same time” (146). 

Bryson opens the chapter by introducing University of Chicago graduate studentClair Patterson, who was attempting to use a new method of lead isotype measurement to date the Earth, and Thomas Midgely, Jr., an engineer and inventor. Despite that lead was known to be dangerous, causing irreversible damage to the nervous system, in the early twentieth century lead was found in a variety of consumer products, including food cans, water storage tanks, and on fruits, as a pesticide. But lead was most prevalent as an additive to gasoline. Midgely was responsible for this addition, noting that tetraethyl lead reduced engine knock, was easy to extract, and was highly profitable. The biggest oil companies adopted this highly toxic gasoline additive and changed the name from lead to ethyl, because it sounded less toxic. Countless production workers died or went insane from lead exposure, but the gasoline companies were good about covering up the casualties.

Midgely also went on to invent the dangerous chlorofluorocarbons, or CFCs, the chemical that went into car air conditioners, deodorant sprays, and refrigerators, and aided in destroying the ozone layer. Ozone is a delicate form of oxygen that soaks up dangerous ultraviolet radiation, protecting life on Earth. However, ozone is fragile, and CFCs are highly destructive. Bryson notes that just “One pound of CFCs can capture and annihilate seventy thousand pounds of atmospheric ozone” (152). In short, CFCs are arguably one of the worst inventions of the twentieth century.

Bryson goes on to mention Willard Libby, who invented radiocarbon dating, which came from the realization that “all living things have within them an isotope of carbon called carbon-14, which begins to decay at a measurable rate the instant they die” (152). By figuring out how much the carbon in a sample had decayed, Libby could reasonably estimate the age of the object. This method allowed scientists to accurately determine the age of bones and other organic remains up to forty thousand years old, after which time the dating becomes unreliable. However, despite the benefits of carbon dating, there are many inherit flaws, including the fact that readings can be thrown off by even theslightest external factors.

An English professor named Arthur Holmes solved the problems inherent to carbon dating. In a similar but more reliable fashion, Holmes measured the decay rate of uranium in lead. While this was a dependable way to date rocks, Holmes also used this method to conclude that the Earth was at least three billion years old. During this same time, professor Harrison Brown of the University of Chicago devised a fresh way to count lead isotopes in igneous rocks. Instead of doing the tedious work himself, he gave the task to Clair Patterson and assured him that she would quickly find the true age of the Earth through this method. After realizing that no rock on Earth was ancient enough to accurately measure, he measured the age of a meteorite. Through this process, Patterson declared that the definitive age of the Earth is 4,550 million years old, a figure that stands unchanged to this day.

Patterson was also the one to discover that there was a lot of lead in the atmosphere. From his measurements, he found that before 1923, the year lead was introduced into gasoline, there was no lead in the atmosphere, but that since, the levels in the atmosphere have skyrocketed. After this discovery, Patterson made it his life’s mission to get lead taken out of gasoline. These efforts led to the Clean Air Act of 1970 and the removal from sale of leaded gasoline in 1986. Immediately lead levels in the blood of Americans fell by 80 percent. 

Bryson opens the chapter by talking about British scientist C.T.R. Wilson, who studied cloud formations. Instead of regularly climbing the summit of Ben Nevis, he built a cloud chamber, a “simple device in which he could cool and moisten the air, creating a reasonable model of a cloud in laboratory conditions” (161). However, much more than a cloud chamber, he discovered that when he accelerated particles through the fake clouds, they left a visible trail. Thus, his device became the first particle detector.

From there, Ernest Lawrence invented an atom smasher known as the cyclotron. It works by accelerating a proton to extremely high speeds and then colliding it into another particle, to see what bounces off. Today’s particle accelerators have evolved from Lawrence’s device, use huge amounts of energy, and are able to “whop particles into such a state of liveliness that a single electron can do forty-seven thousand laps around a four-mile tunnel in a second” (162). Totrap the ever-elusive particles, scientists need millions of gallons of water in underground chambers, where radiation can’t interfere. This all takes a lot of money. The Large Hadron Collider, for example, takes fourteen trillion volts of energy to run and cost $1.5 billion to construct.

Bryson notes that particle physics is vastly expensive, which is why scientists have only uncovered over 150 particles so far. They also aren’t quite sure why these particles exist. As Richard Feynman puts it, “it is very difficult to understand the relationships of all these particles, and what nature wants them for, or what the connections are from one to another” (164). Physicists don’t know when they’ll reach the irreducible bottom, nor what they would find if they ever got there.

To bring simplicity to this highly theoretical field, physicist Murray Gell-Mann invented a new class of particles known as quarks, having taken the name from a line in James Joyce’s Finnegan’s Wake. These quarks are broken down into six categories—up, down, strange, charm, top, and bottom—and these are further broken down into the colors red, green, and blue. This became known as the Standard Model, which Bryson calls a “sort of parts kit for the subatomic world” (165). Gell-Mann’s arrangement basically states that “among the basic building blocks of matter are quarks; these are held together by particles called gluons; and together quarks and gluons form protons and neutrons, the stuff of the atom’s nucleus” (166). This is the simplest model of explaining the world of particles, but it is incomplete, not considering many factors such as gravity or mass.

This is where superstring theory comes in. It states that what were previously thought of as particles are actually strings, or vibrating strands of energy, that “oscillate in eleven dimensions, consisting of the three we know already plus time and seven other dimensions that are, well, unknowable to us” (167). And, as Bryson notes, the theories get even more difficult to understand and bizarre from there—so difficult, in fact, that many physicists have a difficult time determining whether or not a theory is nonsense or science. It seems that no matter how many physicists come up with various theories, it doesn’t appear that there will ever be one definitive theory for physics.

Bryson ends the chapter by stating that “we live in a universe whose age we can’t quite compute, surrounded by stars whose distances we don’t altogether know, filled with matter we can’t identify, operating in conformance with physical laws whose properties we don’t truly understand” (172). 

Bryson opens by talking about Charles Hapgood, a geologist who adamantly denied that there was any correspondence in shape between continents on opposite sides of the Atlantic. He was going off the findings of K.E. Caster and J.C. Mendes’s extensive fieldwork, which somehow concluded that there were no similarities between the continents. This, of course, was completely false, because not only are the rock formations on both sides of the Atlantic in fact similar, they are the same.

The first geologist to notice this was an amateur named Frank Bursley Taylor. By regarding how similar the facing coastlines of Africa and South America were, he came up with the idea that continents had moved around once upon a time. He also hypothesized that this shifting could have caused the mountains to rise. Although he was correct, he couldn’t provide any evidence to support his claim, and no one accepted his theory. However, in Germany, a theorist named Alfred Wegener observed that animal fossils were frequently found on opposite sides of oceans that were too wide to swim. Wegener came up with the theory that “the world’s continents had once come together in a single landmass he called Pangaea, where flora and fauna had been able to mingle, before the continents split apart and floated off to their present positions” (174).

According to Bryson, Wegener’s idea wasn’t widely accepted because the consensus of the time was that the Earth moved up and down, not sideways. This could be visualized by the baked apple theory, which suggested that “as the molten Earth had cooled, it had become wrinkled in the manner of a baked apple, creating ocean basins and mountain ranges” (175). Of course, this was wrong, and Wegener’s theory was lacking in many ways. It wasn’t until Arthur Holmes came along and suggested that “radioactive warming could produce convection currents with the Earth” that people began to accept the idea that continents had once moved (176). Holmes’s idea became known as the continental drift theory, and the fundamentals of it are still accepted today.

Despite the truth of Holmes’s theory, the problem remained that no one knew where the sediment went. Since, for example, Earth’s rivers carry 500 million tons of calcium to the seas each year, if one were to multiply this number since the beginning of time, “the ocean bottom should by now be well above the ocean tops” (177). This predicament was answered by Harry Hess, a mineralogist who found that the ocean floors weren’t full of sediment, like everyone had assumed, rather they were full of canyons, trenches, and crevasses. During this same time in the 1950s, oceanographers took more detailed surveillance of the ocean floors and found that the biggest mountain range on Earth was mostly under water (some of its peaks rose above the water and created islands or archipelagoes). From these findings, Hess determined that “new ocean crust was being formed on either side of the central rift, then being pushed away from it as new crust came along behind it. The Atlantic floor was effectively two large conveyor belts, one carrying crust toward North America, the other carrying crust toward Europe” (179). This theory became known as seafloor spreading, and helped to explain where all the sediment went.

The continental drift theory developed into plate tectonics when it was discovered that the entire Earth’s crust was in motion, not just continents. Bryson points out that today “we know that Earth’s surface is made up of eight to twelve big plates (depending on how you define big) and twenty or so smaller ones, and they all move in different directions and at different speeds” (181). If the plates keep shifting as it’s assumed they have always done, Bryson notes that eventually some interesting geological changes will occur, including California floating off and becoming part of Madagascar and Africa pushing northward into Europe.