We find ourselves in a bewildering world. We want to makesense of what we see around us and to ask: What is thenature of the universe? What is our place in it and where didit and we come from? Why is it the way it is?
To try to answer these questions we adopt some “worldpicture.” Just as an infinite tower of tortoises supporting the fiatearth is such a picture, so is the theory of superstrings. Bothare theories of the universe, though the latter is much moremathematical and precise than the former. Both theories lackobservational evidence: no one has ever seen a giant tortoisewith the earth on its back, but then, no one has seen asuperstring either. However, the tortoise theory fails to be agood scientific theory because it predicts that people should beable to fall off the edge of the world. This has not been foundto agree with experience, unless that turns out to be theexplanation for the people who are supposed to havedisappeared in the Bermuda Triangle!
The earliest theoretical attempts to describe and explain theuniverse involved the idea that events and natural phenomenawere controlled by spirits with human emotions who acted in avery humanlike and unpredictable manner. These spiritsinhabited natural objects, like rivers and mountains, includingcelestial bodies, like the sun and moon. They had to beplacated and their favor sought in order to ensure the fertilityof the soil and the rotation of the seasons. Gradually, however,it must have been noticed that there were certain regularities:
the sun always rose in the east and set in the west, whetheror not a sacrifice had been made to the sun god. Further, thesun, the moon, and the planets followed precise paths acrossthe sky that could be predicted in advance with considerableaccuracy. The sun and the moon might still be gods, but theywere gods who obeyed strict laws, apparently without anyexceptions, if one discounts stories like that of the sun stoppingfor Joshua.
At first, these regularities and laws were obvious only inastronomy and a few other situations. However, as civilizationdeveloped, and particularly in the last 300 years, more andmore regularities and laws were discovered. The success ofthese laws led Laplace at the beginning of the nineteenthcentury to postulate scientific determinism; that is, he suggestedthat there would be a set of laws that would determine theevolution of the universe precisely, given its configuration at onetime.
Laplace’s determinism was incomplete in two ways. It did notsay how the laws should be chosen and it did not specify theinitial configuration of the universe. These were left to God.
God would choose how the universe began and what laws itobeyed, but he would not intervene in the universe once it hadstarted. In effect, God was confined to the areas thatnineteenth-century science did not under-stand.
We now know that Laplace’s hopes of determinism cannotbe realized, at least in the terms he had in mind. Theuncertainty principle of quantum mechanics implies that certainpairs of quantities, such as the position and velocity of aparticle, cannot both be predicted with complete accuracy.
Quantum mechanics deals with this situation via a class ofquantum theories in which particles don’t have well-definedpositions and velocities but are represented by a wave. Thesequantum theories are deterministic in the sense that they givelaws for the evolution of the wave with time. Thus if oneknows the wave at one time, one can calculate it at any othertime. The unpredictable, random element comes in only whenwe try to interpret the wave in terms of the positions andvelocities of particles. But maybe that is our mistake: maybethere are no particle positions and velocities, but only waves. Itis just that we try to fit the waves to our preconceived ideasof positions and velocities. The resulting mismatch is the causeof the apparent unpredictability.
In effect, we have redefined the task of science to be thediscovery of laws that will enable us to predict events up to thelimits set by the uncertainty principle. The question remains,however: how or why were the laws and the initial state of theuniverse chosen?
In this book I have given special prominence to the lawsthat govern gravity, because it is gravity that shapes thelarge-scale structure of the universe, even though it is theweakest of the four categories of forces. The laws of gravitywere incompatible with the view held until quite recently thatthe universe is unchanging in time: the fact that gravity isalways attractive implies that the universe must be eitherexpanding or contracting. According to the general theory ofrelativity, there must have been a state of infinite density in thepast, the big bang, which would have been an effectivebeginning of time. Similarly, if the whole universe recollapsed,there must be another state of infinite density in the future, thebig crunch, which would be an end of time. Even if the wholeuniverse did not recollapse, there would be singularities in anylocalized regions that collapsed to form black holes. Thesesingularities would be an end of time for anyone who fell intothe black hole. At the big bang and other singularities, all thelaws would have broken down, so God would still have hadcomplete freedom to choose what happened and how theuniverse began.
When we combine quantum mechanics with general relativity,there seems to be a new possibility that did not arise before:
that space and time together might form a finite,four-dimensional space without singularities or boundaries, likethe surface of the earth but with more dimensions. It seemsthat this idea could explain many of the observed features ofthe universe, such as its large-scale uniformity and also thesmaller-scale departures from homogeneity, like galaxies, stars,and even human beings. It could even account for the arrowof time that we observe. But if the universe is completelyself-contained, with no singularities or boundaries, andcompletely described by a unified theory, that has profoundimplications for the role of God as Creator.
Einstein once asked the question: “How much choice didGod have in constructing the universe?” If the no boundaryproposal is correct, he had no freedom at all to choose initialconditions. He would, of course, still have had the freedom tochoose the laws that the universe obeyed. This, however, maynot really have been all that much of a choice; there may wellbe only one, or a small number, of complete unified theories,such as the heterotic string theory, that are self-consistent andallow the existence of structures as complicated as humanbeings who can investigate the laws of the universe and askabout the nature of God.
Even if there is only one possible unified theory, it is just aset of rules and equations. What is it that breathes fire into theequations and makes a universe for them to describe? Theusual approach of science of constructing a mathematical modelcannot answer the questions of why there should be a universefor the model to describe. Why does the universe go to all thebother of existing? Is the unified theory so compelling that itbrings about its own existence? Or does it need a creator, and,if so, does he have any other effect on the universe? And whocreated him?
Up to now, most scientists have been too occupied with thedevelopment of new theories that describe what the universe isto ask the question why. On the other hand, the people whosebusiness it is to ask why, the philosophers, have not been ableto keep up with the advance of scientific theories. In theeighteenth century, philosophers considered the whole of humanknowledge, including science, to be their field and discussedquestions such as: did the universe have a beginning?
However, in the nineteenth and twentieth centuries, sciencebecame too technical and mathematical for the philosophers, oranyone else except a few specialists. Philosophers reduced thescope of their inquiries so much that Wittgenstein, the mostfamous philosopher of this century, said, “The sole remainingtask for philosophy is the analysis of language.” What acomedown from the great tradition of philosophy from Aristotleto Kant!
However, if we do discover a complete theory, it should intime be understandable in broad principle by everyone, not justa few scientists. Then we shall all, philosophers, scientists, andjust ordinary people, be able to take part in the discussion ofthe question of why it is that we and the universe exist. If wefind the answer to that, it would be the ultimate triumph ofhuman reason - for then we would know the mind of God.
ALBERT EINSTEINEinstein’s connection with the politics of the nuclear bomb iswell known: he signed the famous letter to President FranklinRoosevelt that persuaded the United States to take the ideaseriously, and he engaged in postwar efforts to prevent nuclearwar. But these were not just the isolated actions of a scientistdragged into the world of politics. Einstein’s life was, in fact, touse his own words, “divided between politics and equations.”
Einstein’s earliest political activity came during the First WorldWar, when he was a professor in Berlin. Sickened by what hesaw as the waste of human lives, he became involved inantiwar demonstrations. His advocacy of civil disobedience andpublic encouragement of people to refuse conscription did littleto endear him to his colleagues. Then, following the war, hedirected his efforts toward reconciliation and improvinginternational relations. This too did not make him popular, andsoon his politics were making it difficult for him to visit theUnited States, even to give lectures.
Einstein’s second great cause was Zionism. Although he wasJewish by descent, Einstein rejected the biblical idea of God.
However, a growing awareness of anti-Semitism, both beforeand during the First World War, led him gradually to identifywith the Jewish community, and later to become an outspokensupporter of Zionism. Once more unpopularity did not stop himfrom speaking his mind. His theories came under attack; ananti-Einstein organization was even set up. One man wasconvicted of inciting others to murder Einstein (and fined amere six dollars). But Einstein was phlegmatic. When a bookwas published entitled 100 Authors Against Einstein, heretorted, “If I were wrong, then one would have been enough!”
In 1933, Hitler came to power. Einstein was in America, anddeclared he would not return to Germany. Then, while Nazimilitia raided his house and confiscated his bank account, aBerlin newspaper displayed the headline “Good News fromEinstein - He’s Not Coming Back.” In the face of the Nazithreat, Einstein renounced pacifism, and eventually, fearing thatGerman scientists would build a nuclear bomb, proposed thatthe United States should develop its own. But even before thefirst atomic bomb had been detonated, he was publicly warningof the dangers of nuclear war and proposing internationalcontrol of nuclear weaponry.
Throughout his life, Einstein’s efforts toward peace probablyachieved little that would last - and certainly won him fewfriends. His vocal support of the Zionist cause, however, wasduly recognized in 1952, when he was offered the presidency ofIsrael. He declined, saying he thought he was too naive inpolitics. But perhaps his real reason was different: to quote himagain, “Equations are more important to me, because politics isfor the present, but an equation is something for eternity.”
GALILEO GALILEIGalileo, perhaps more than any other single person, wasresponsible for the birth of modern science. His renownedconflict with the Catholic Church was central to his philosophy,for Galileo was one of the first to argue that man could hopeto understand how the world works, and, moreover, that wecould do this by observing the real world.
Galileo had believed Copernican theory (that the planetsorbited the sun) since early on, but it was only when he foundthe evidence needed to support the idea that he started topublicly support it. He wrote about Copernicus’s theory inItalian (not the usual academic Latin), and soon his viewsbecame widely supported outside the universities. This annoyedthe Aristotelian professors, who united against him seeking topersuade the Catholic Church to ban Copernicanism.
Galileo, worried by this, traveled to Rome to speak to theecclesiastical authorities. He argued that the Bible was notintended to tell us anything about scientific theories, and that itwas usual to assume that, where the Bible conflicted withcommon sense, it was being allegorical. But the Church wasafraid of a scandal that might undermine its fight againstProtestantism, and so took repressive measures. It declaredCopernicanism “false and erroneous” in 1616, and commandedGalileo never again to “defend or hold” the doctrine. Galileoacquiesced.
In 1623, a longtime friend of Galileo’s became the Pope.
Immediately Galileo tried to get the 1616 decree revoked. Hefailed, but he did manage to get permission to write a bookdiscussing both Aristotelian and Copernican theories, on twoconditions: he would not take sides and would come to theconclusion that man could in any case not determine how theworld worked because God could bring about the same effectsin ways unimagined by man, who could not place restrictionson God’s omnipotence.
The book, Dialogue Concerning the Two Chief WorldSystems, was completed and published in 1632, with the fullbacking of the censors - and was immediately greetedthroughout Europe as a literary and philosophical masterpiece.
Soon the Pope, realizing that people were seeing the book as aconvincing argument in favor of Copernicanism, regretted havingallowed its publication. The Pope argued that although the bookhad the official blessing of the censors, Galileo had neverthelesscontravened the 1616 decree. He brought Galileo before theInquisition, who sentenced him to house arrest for life andcommanded him to publicly renounce Copernicanism. For asecond time, Galileo acquiesced.
Galileo remained a faithful Catholic, but his belief in theindependence of science had not been crushed. Four yearsbefore his death in 1642, while he was still under house arrest,the manuscript of his second major book was smuggled to apublisher in Holland. It was this work, referred to as Two NewSciences, even more than his support for Coper............