reviewed by Gabrielle Chong
One of the most stunning revelations in any scientific field in the last half-century came in 1998, when Saul Perlmutter, Brian P. Schmidt, and Adam g. Riess discovered that the expansion of the universe is accelerating. This subsequently earned them a shared Nobel Prize in Physics. The Book of Nothingness, written by noted British astrophysicist/mathematician John D. Barrow and published just four years later, was one of the earliest attempts to explain the profound implications of this discovery to the general public.
Unlike more recent books on the same topic, such as the current bestseller A Universe Out of Nothing: Why There is Something Rather Than Nothing by Lawrence Krauss – which dive rather straightforwardly into the heady technicalities of physics, The Book of Nothingness is more of a generalist treatise on the broad history of ideas on the vacuum. In fact, the first 40% of the book is completely devoted to the concept of vacuums in a wide variety of non-scientific literature.
The Book of Nothingness begins with a charming overview of the historical development of the number zero. Although the cipher figure was invented independently among a number of primitive civilizations, it was the Indians who gave it its additive value that enabled the emergence of the decimal system. Curiously, Barrow points out the only civilizations that invented the zero were all highly superstitious practitioners of mysticism. The Indians, for example, also associated the digit with a number of religious and philosophical themes of nothingness. Conversely, the ancient greeks, who were otherwise the most scientifically significant early civilization, could not tolerate the idea of zero. For the greek philosophers, the concept of a cipher was logically dissonant, as encapsulated by Parmenides’ maxim, ex nihilo nihil fit (nothing comes from nothing), or Aristotle’s “Nature abhors a vacuum”.
As the ancient philosophers argued over the unsettled debate on how something can come out of nothing, the concept of zero gained prominence in the realm of literature and theology in the following millenium. While writers like Shakespeare made the best out of innocuous puns and wordplay on nothing (e.g. his prominent comedy “Much Ado About Nothing”), theologians faced a significant challenge on the philosophical implications of nothing; if a vacuum could exist, it would disprove the omnipresence of God. As the feud between theologians, philosophers and scientists escalated towards the end of the middle ages, interest in the ancient engineering challenge of creating a vacuum revived. By the mid 1600s, the first vacuum pump – the Magdeburg hemispheres – was invented by Otto von Guericke and memorably demonstrated with the failure of 32 horses to pull it apart, highlighting the power of atmospheric pressure. At about the same time, Blaise Pascal began his experiments in measuring air pressure. The results dealt a significant blow to the church – as air pressure decreased proportionately with height above sea level, one could extrapolate the measurements to postulate that there exists a certain point above earth where air pressure was zero. This dark chasm, which we know now as space, shattered any beliefs of an infinite extension of the earth’s dominion.
But, as Barrow notes, the concept of vacuum would undergo several more cycles of derision and revival among the scientific elite as scientific revolutions come and go. The first major effort to develop a coherent picture of the vacuum came after Newton. While Newtonian physics were astoundingly successful in predicting a wide variety of physical phenomena (on a human scale), physicists struggled with the idea of planets exerting gravitational forces over vast distances of empty space. In order to explain physical actions in the absence of mass and energy, the ether was created – an elusive substance thought to permeate the universe. This was, of course, debunked with the advent of Einstein’s theory of general relativity. With this, the ether retired and the vacuum assumed another period of scientific dormancy.
Though it is foreseeable that more technically-minded readers will find the entire first half of the book – dedicated to the history of the vacuum – as somewhat incoherent and even tiring (Barrow has been rather ambitious in attempting to weave the philosophical, literary, theological, historical, and scientific elements of the concept of nothing into a seamless story), it provides a fun warm-up for the more generalist reader in making a transition into the much more dense second half of the book. The last half deals with the implications of the latest discoveries in quantum mechanics and astrophysics on the nature of the spatial vacuum. Here, the explanations are about as lucid as those found in Krauss’s A Universe From Nothing.
As Barrow skillfully narrates, the latest conundrum on the vacuum began almost a century ago when Einstein arbitrarily added a ‘cosmological constant’ to one of his field equations that would result in a static universe. By 1929, Hubble discovered the expansion of the universe, shattering the image of an unmoving universe. Einstein later lamented to George Gamow that the cosmological constant was the biggest blunder of his life. However, the 1998 discovery that the universe is not only expanding, but that its expansion is also accelerating, resurrected conjectures on the nature of the vacuum. As it turns out, even if one removes every single bit of mass-energy that it is possible to remove from a spatial region, what remains is not an absence of energy, but the lowest state of energy possible. This vacuum energy, an innate feature of space itself, acts as an anti-gravitational force that speeds up the expansion of the universe and is set to become the dominant force in the universe someday as space grows forever. Cosmological constant has been currently used to explain vacuum energy, perhaps Einstein’s ‘biggest blunder’ (though wrongly applied) was really just an amazing prediction!
Overall, I enjoyed The Book of Nothingness, and Barrow surely has a gift for scientific narration. Being a regular reader of popular physics books, I would rank the book intermediate in terms of accessibility for the educated layman. However, anyone who picks up the book today should bear in mind that developments in astrophysics move at light speed, and that many of the latest discoveries uncovered in this book were published a decade ago.
ABOUT THE AUTHOR:
Gabrielle Chong Yong Wei is a philosophy student at Wellesley who is fond of science.