Zapped

by Bob Berman

  By 1954, researchers had switched to high-altitude balloon testing, but the hazard still remained unknown. The animal of choice was often an odd kind of black mouse, because the pigmentation in its hair follicles would be destroyed by radiation, which would immediately turn them white. But good news: these mice stayed predominantly dark. By the following year, Simons had completed dozens of test flights, and the animals, mostly Java macaques, were returning to Earth unharmed. It was therefore only in 1955 that cosmic rays were finally discovered to be nonlethal for future astronauts—at least during missions of relatively short duration. In 1957, just a few months before the Soviets shocked America with the first-ever launch of their orbiting satellite Sputnik 1, the air force sent test pilot David Simons up in a balloon to an altitude of over one hundred thousand feet for more than twenty-four hours—along with radiation monitors—without any ill effects. Thus it was only as the curtain was actually rising on space travel that we finally got the last-minute green light for short-duration human missions.

  But just because cosmic rays didn’t cause rats, monkeys, or astronauts to drop dead on the spot doesn’t mean they can’t mess with your health. Cosmic rays do something curious as they fly into our atmosphere. Striking air molecules at a height of around thirty-five miles, they break atoms apart the way a cue stick breaks up a rack of billiards. The atoms’ contents rain down toward the surface at nearly the speed of light. Among the detritus flying off are muons, which are sometimes regarded as cosmic rays themselves. These strange transient particles are neither superheavy nor particularly lightweight. Rather, they each have a mass equal to around 208 electrons. They also have a short life span. With a half-life of just two-millionths of a second, a muon quickly disintegrates and vanishes, leaving behind a swarm of ordinary electrons and some neutrinos that essentially weigh nothing. Harmless stuff.

  But before they vanish, muons can indeed cause harm if they strike the wrong bit of genetic material in a cell nucleus. This is indeed one of the causes of the “spontaneous” tumors that have always plagued the human race. Nor can you hide from them. Some 240 muons flash through your body every second. More hit you if you live in hazardously high-up Denver, and none reaches you if you’ve chosen a home deep underground or spend most of your time in a subterranean parking garage.

  Muons reveal something truly strange. You see, if you do the math, you’ll notice that because they are created thirty-five miles up, zoom downward at almost the speed of light, and live for just two-millionths of second before vanishing, they should not logically penetrate our bodies at all. Even at an ultrahigh velocity, no object can travel more than a few city blocks in two-millionths of a second. So how can muons possibly make it all the way here to the surface of our planet?

  This is the sort of thing that was utterly inexplicable until Einstein created his two relativity theories, in 1905 and 1915. Only then did we learn that the passage of time and the distance between objects warp and mutate according to local conditions. Thus muons at their high speed would observe (if they were conscious) that the distance between them and the ground is not thirty-five miles but rather just a single city block. The gap between the upper atmosphere and the ground has dramatically shrunk, enabling our muons to arrive at the surface of the earth before their two-microsecond life span has elapsed.

  But we observers see something very different. To us, the distance between the place where the muons were first created and the spot where they strike the ground is not a mere city block but rather thirty-five miles. We observe no change in the muon’s path or the distance it traverses to arrive in our bedrooms. However, our measurements uncover something else: we see the muons experiencing a slowed-down rate of time. Their lives unfold in slow motion. And because time is passing at a glacial rate for the muons, their rate of decay is similarly retarded so that they no longer vanish in a couple of microseconds. Rather, their half-life has been stretched out, and they now live so long that they are able to reach the ground during their newly enhanced lifetimes.

  We see their time slowed down because their decay happens far more slowly. Muons, by contrast, feel their time passing normally but experience the distance in front of them as contracted. It’s exactly what Einstein predicted. Neither space nor time is absolute: they both warp and mutate depending on local conditions, such as speed, which is why he named his theory relativity.

  To use real numbers, at 99.9999999 percent of light’s speed, a muon experiences the distance in front of it contracted by a factor of 22,361. The original thirty-five-mile gap between it and the earth’s surface has suddenly shrunk to a mere eight feet. And our muon says, “Heck, I can cover eight feet within my short lifetime.” And it does.

  We, on the other hand, observe the muon’s time contract so much that each hour shrinks to just one-sixth of a second. From either perspective, the muon gets here and penetrates our bodies. It’s just that we and the muon disagree about the amount of distance it covered and how much time it took.

  That was Einstein’s whole point: neither of us is right or wrong. There simply is no absolute passage of time. Nor is there some inviolable thing called distance or separation. Indeed he showed that the cosmos does not consist of any sort of fixed dimensions. Rather, the universe is sizeless.

  These relativistic effects mean that muons, which might at first seem harmless, can actually harm us, and are indeed sometimes regarded as a kind of cosmic ray themselves. So along with the primary cosmic rays that create them, muons, too, belong on our list of invisible entities that continuously penetrate our bodies—and can sometimes kill us.

  CHAPTER 20

  Beams from the Universe’s Birth

  Some forms of invisible light are truly omnipresent. Satellite transmissions, TV stations, and cell towers continuously flood your bedroom with radio waves and microwaves. But before these technologies existed, even in the era of the Neanderthals, every cave dweller with furry underwear was still bombarded with nonstop microwaves, even if we didn’t realize this until 1964. This is the natural “light” that arrives equally from all directions. It is the leftover energy from the creation of the universe.

  The story of its discovery is the tale of how we stumbled upon one of the most momentous, glittery—and least disputable—keys to the nature of the cosmos.

  It requires a rewind all the way back to the mid-nineteenth century, to a little-known Edgar Allan Poe essay called “Eureka.” The man renowned for his poem “The Raven” muttered “nevermore” to the prevailing belief that the universe had existed more or less eternally in the same unvarying state. Poe mused that the cosmos may have begun as a sort of superdense “egg” that then exploded and expanded.

  The idea competed for decades with the “steady-state” notion of a universe that pretty much always looks the same. Even after Edwin Hubble showed in 1929 that the universe is expanding, which does suggest an explosive genesis event, this still didn’t kill the steady-state idea. After all, if a single new atom of hydrogen pops out of nothingness once per century in every parcel of space the volume of a football stadium, that would replenish the empty space created by expanding outrushing galaxies. It could supply the eventual material for new stars. Such a slow, constant genesis would be very hard to detect or disprove.

  So which was it? To some, including British theorist Fred Hoyle, the notion of the entire cosmos popping violently out of nothing one Saturday morning seemed preposterous. In 1949 he pejoratively referred to the absurd idea of a “big bang,” and the term stuck, but without Hoyle’s negative connotation. Meanwhile, who was to say which was more far-fetched—a universe that appears suddenly all at once or one that drips into existence atom by atom, like a leaky faucet? Either way, we’re apparently getting something from nothing, or perhaps from an unknown dimension. Both ideas were presented in 1950s textbooks as equally plausible alternative accounts of our universe’s genesis.

  In the 1940s, scientists such as George Gamow calculated that if everything did begin sudden
ly, that blinding initial energy should still be around. True, the expansion of space would stretch out all the energy waves, redshifting the brilliance. But this invisible leftover energy ought to still be detectable. He figured that this cosmic background noise, this relic of the big bang, would produce an energy equivalent of twenty-five degrees above absolute zero on the Celsius scale.

  Back then we knew neither the true rate at which the cosmos was expanding nor its actual size, and that made the exact “invisible light” frequency impossible to gauge with any precision. Nonetheless the idea was sound, and other physicists, including those in the Soviet Union, came up with various frequencies and equivalent temperature energies that ought to be filling all of space.

  By the 1960s, the consensus was that such an energy should only be a few degrees above absolute zero, the point where atomic motion stops entirely, which corresponds to wimpy electromagnetic waves only a few millimeters from crest to crest with a frequency of a few billion waves per second. In other words, they’d be microwaves. Some considered building a special radio telescope that might pick up these invisible rays, these leftovers from the beginning of time.

  Everything changed on May 20, 1964. That’s when two radio astronomers, Robert Wilson and Arno Penzias, who were working for Bell Labs, discovered, completely by accident, a form of radiation known as the cosmic microwave background (CMB).

  The two men had been asked to help calibrate Bell’s large horn-shaped radio antenna in Holmdel, New Jersey, designed for future satellite use, which at that time meant radio signals reflected off the large balloonlike Echo 1 satellite. After all, those were the opening years of what was to be a revolution in orbiting satellite technology: Sputnik 1 had been launched just six and a half years earlier. So they were working on baselines and calibrating against what should have been a background of outer-space silence. But they couldn’t get rid of an annoying hum.

  When they turned the directional antenna, the odd buzz remained. When the sun went down, and when the galaxy’s center paraded through the sky, the hum persisted, as loud as before. When TV stations went off the air after midnight, the hum continued. It maintained exactly the same volume at all times.

  The scientists had no idea what they were experiencing. Maybe it was thermal radiation—heat—perhaps caused by some pigeons they’d found nesting in the antenna’s metal crevices. They had an exterminator humanely remove the birds and release them a hundred miles away. Yes, the birds—the same ones—eventually returned, but in the meantime, the buzz remained; getting rid of the birds didn’t affect it at all.

  The physicists had no idea that just thirty-seven miles away, in that very same state of New Jersey, in Princeton, theoretical physicists were expecting exactly that kind of microwave hum to be emanating from the sky but were unaware of any existing radio telescope that might detect it!

  That was the situation during the spring of 1964. One pair of physicists had discovered the buzz from the big bang but had no idea what it was. A nearby group knew that there should be a microwave hum if the big bang was real but didn’t think there was any way to find it.

  Then came an amazing coincidence. By chance, on an airline trip, Arno Penzias was seated next to Bernard Burke, a radio astronomer working at the Department of Terrestrial Magnetism, in Washington, DC, who knew about the Princeton theoretical work. Hearing Penzias describe his problematic hum, Burke urged him to phone Bob Dicke at Princeton University.

  When Penzias did, Dicke got off the phone and said to his colleagues, “Boys, we’ve been scooped!”

  So it was that Wilson and Penzias discovered the ancient light that began saturating the universe soon after its creation. It was as accidental as finding a hundred-dollar bill in an old jacket pocket. It required no act of genius. But it was so momentous that both men were awarded the 1978 Nobel Prize in Physics. It was arguably the most easily earned Nobel in history. (Perhaps it was Burke who ought to have landed the Nobel!)

  The milestone microwave discovery put the big bang theory on solid ground. It was powerful evidence that the universe did begin as a tiny sphere smaller than a baseball some 13.8 billion years ago.

  Here’s what apparently happened. For reasons that are mysterious and are likely to remain so, the cosmos emerged as a pinpoint from apparent nothingness, then inflated far faster than the speed of light. This inflation lasted for only a fraction of a second, then the cosmos started coasting outward on its own momentum. Conditions were so unimaginably hot that everything was pure energy. The first subatomic particles (neutrinos) formed within this energy matrix just one second later, while other particles required several minutes. Meanwhile the whole thing kept explosively growing in size. For the next 377,000 years, all forms of light, visible and invisible, were unable to travel through the opaque foggy soup of particles, which would instantly absorb and then reradiate the energy. But suddenly, 377,000 years after the big bang—a momentous moment that perhaps deserves its own holiday—conditions sufficiently cooled to allow protons to capture electrons. Neutral hydrogen atoms were born everywhere at once. At this moment, space became transparent for the first time.

  Suddenly the fog lifted. The dazzling light that pervaded everything was free to travel across the universe. It is this light that we see when we detect the cosmic microwave background.

  CMB would be blinding if the universe weren’t expanding. Indeed it would be so intense and energetic that it would sterilize everything and prevent planets and life forms from existing. But because space itself continuously grows in size, all the energy waves traversing it are continuously stretched out. And as we know, the longer a wave gets, the lower its energy becomes.

  When the universe was half its current age, it was twice as hot as it is now. Back then, CMB, though invisible, consisted of shorter, more powerful energies that had faster frequencies. It still wasn’t the original, lethally blistering soup of gamma rays and X-rays, but it was a very different background from the benign radio frequencies we detect today. Back then, the background would have been classified as infrared rays.

  Today the waves have been stretched further so that they’re now wimpy microwaves. Precise measurements of the CMB must be performed above the earth’s atmosphere to prevent their absorption by the air. These measurements were first made by the COBE (Cosmic Background Explorer) satellite, then by a higher-sensitivity microwave-measuring satellite called WMAP (Wilkinson Microwave Anisotropy Probe), which stopped functioning in 2010. The measurements are vital to understanding how the universe evolved.

  They show that the CMB has a smooth thermal “black body spectrum,” the kind that would be emitted by an object shedding heat evenly. The energy radiates at an effective temperature of 2.72548 degrees Kelvin (equal to 2.73 degrees Celsius above absolute zero). Or, if you prefer, this all-pervasive glow measures minus 455 degrees Fahrenheit.

  This radiance has a peak emission of 160.2 gigahertz, in the microwave part of the spectrum. If expressed as wavelength, the waves are 1.871 millimeters apart, approximately the width of apple seeds.

  The glow is extremely uniform in all directions. This isotropy, or smoothness, is exactly what we should observe if the energy came from a big bang that initially inflated at faster than light speed. But the evenness is not quite perfect. Interestingly, there are tiny residual energy variations of around one part in eighty thousand from each little section of the sky to the next. This anisotropy between each little section of sky and the next varies with the size of the region examined but remains small everywhere. The simplest and most logical explanation is that these density differences in the early universe were globs of energy, then matter, that eventually formed structures and that we see today as stars and galaxies.

  The microwaves make the big bang very plausible and the steady-state theory highly improbable. Of course the ultimate reason for the big bang, or even an accurate (or approximate) description of it, is unknown. A universe popping out of empty space offers no hint of any antecedent conditions,
no clue of what may have precipitated such an astonishing occurrence. Thus the all-pervasive invisible background microwaves provide some clarity about the enormous mystery of cosmic genesis—while presenting an equally big enigma at which we can only shrug in wonder.

  CHAPTER 21

  Energy from Our Minds

  Even if it takes us on a temporary detour from mainstream science, we can’t ignore a popular, far-out aspect of unseen rays and waves: energy transmitted from the brain of one person to another.

  Most people believe that the brain emits waves. Many suspect that if there’s such a thing as ESP (extrasensory perception), it’s because our minds transmit in some way. So let’s start by confirming: are there waves coming out of our brains?

  In a way, yes. If we placed electrodes on your skull, they would detect regular rhythms, or pulsations, that vary in several ways. Even better, these electrical rhythms correspond with what your brain is doing!

  Just as electromagnetic waves have discrete frequencies, so do brain waves. They’ve been mapped and named. Unlike radio waves and infrared waves, which vibrate millions and billions of times a second, the brain’s repetitive patterns are much slower. They’re caused by neurons firing and simultaneously pulsing in unison at the relatively sluggish pace of a few dozen to a hundred times a second.

  The main brain waves are called:

  • beta waves (13–38 Hz), which are generated when the brain is active—i.e., during problem solving, conversation, and so on;

  • gamma waves (39–100 Hz), also emitted when the brain is active;

  • alpha waves (8–13 Hz), observed during relaxation;

  • delta waves (very slow, fewer than four per second), which occur during sleep; and