Why Is There Something and Not Nothing?
Surely there is one major question that I haven't been able to answer, one central issue that a
naturalistic approach cannot possibly address. Why does anything exist at all? Much astrophysical
evidence supports the theory that the universe emerged from a very hot, dense state around fourteen
billion years ago, in a big bang that instituted time and space. But where did the big bang come from?
Few educated people now buy the biblical picture that the world was created just six thousand years
ago, but there is still some appeal to the idea that God made the big bang and thereby created the
universe. Problems with this view are easily spotted, such as how a nonmaterial being managed to
create matter and energy, but there is something more satisfying about the idea of a creator than about
the idea of our universe just popping into existence through some kind of inexplicable quantum
fluctuation. Theology still seems more explanatory than does magic.
Recently, however, an alternative to both theology and magic has been proposed by two
distinguished physicists, Paul Steinhardt and Neil Turok. They have developed a new theory of a
cyclic universe, according to which our universe came into existence because of the repeatable
collision between two strange objects called branes. The cyclic model is based on the leading
approach to fundamental physics, string theory, according to which matter is composed of vibrating
stringlike objects operating in more dimensions than the one temporal and three spatial ones familiar
from our everyday experience. A brane (short for “membrane”) is a multidimensional surface that can
move, stretch, curve, and collide with similar constituents. According to Steinhardt and Turok, our
universe began with a violent transition from a low-energy density state to a very high-energy density
state consisting of the hot plasma that constituted the big bang. The energy produced will eventually
decay, leading back over a trillion years or so to the state in which a brane collision could produce
another big bang, with repetitions at regular intervals throughout cosmic history, past and future. In
each cycle, there is a big bang followed by stages dominated successively by radiation, matter, and
energy, leading to contraction and eventually another big bang.
Steinhardt and Turok present evidence that the cyclic theory matches all the current astronomical
observations with the same accuracy as the modified big bang theory, and show how it potentially can
explain and unify some aspects of the universe beyond the range of the big bang theory. No one yet
knows whether the cyclic universe theory will become an accepted part of astrophysics, in part
because it has been difficult to perform experiments to provide evidence that would support the
acceptance of string theory, which the cyclic theory presupposes. Nevertheless, I mention the cyclic
model here because it shows the possibility of an evidence-based answer to the question of why there
is something and not nothing. According to the model, there has always been something, namely,
branes, which are the historical causes of the existence of an infinite number of universes, including
ours. The main explanation of the existence of familiar things such as the sun, the planets, and
members of our own species is the big bang history of our universe, which originated through the
brane mechanism that Steinhardt and Turok propose. Perhaps the cyclic universe is not emotionally
satisfying, because it stands far from providing any kind of reassurance about the meaning of the
universe and our place in it. But it is potentially cognitively satisfying because it provides a
nonmysterious mechanism by which our universe could have come to be. If I someday write a second
edition of this book, I hope it will have a chapter section called “Branes and the Meaning of Life.”
Steinhardt and Turok reject the popular anthropic principle, according to which the complexity of
the universe is connected with our ability to exist in it as observers, as if the universe were somehow
fine-tuned to produce humans. They grant that the physical laws and conditions that govern the
universe must be compatible with the fact that life exists, but this fact tells us nothing about the origins
of those laws and conditions. Some physicists suggest that our planet lies in an unusual universe out
of a multiverse of possibilities, finely tuned as a prerequisite for life to evolve. In contrast, the cyclic
model sees our universe as arising from physical mechanisms, not abstract ideas such as the
multiverse and fine tuning to support life.
I see the anthropic principle as yet another attempt to stage a Ptolemaic counterrevolution, aiming
to put human minds back at the center of reality. This attempt is no more successful than its many
predecessors, including Kant's theory of knowledge, Husserl's phenomenology, Buddhist mysticism,
New Age wishful spirituality, postmodernism, the Wittgensteinian defense of everyday concepts, and
consciousness-based interpretations of quantum mechanics. Rejecting idealism and the lure of
dualism, we need to comprehend the insights of physics, biology, and neuroscience that our minds are
just another physical process in a vast universe. The cyclic theory shows how this universe might
have come into existence through a physical mechanism, without generating spurious reassurance
about the centrality of human thinking to reality. Only in the past few hundred thousand years, out of
the many billions of years that the universe has existed, have human minds been around to interpret
reality. We have no way of ever knowing whether other kinds of minds evolved in previous cycles of
expansion before our universe was formed, or whether new kinds will evolve in future cycles
trillions of years from now.
The Future of Wisdom
Why Is There Something and Not Nothing?Surely there is one major question that I haven't been able to answer, one central issue that anaturalistic approach cannot possibly address. Why does anything exist at all? Much astrophysicalevidence supports the theory that the universe emerged from a very hot, dense state around fourteenbillion years ago, in a big bang that instituted time and space. But where did the big bang come from?Few educated people now buy the biblical picture that the world was created just six thousand yearsago, but there is still some appeal to the idea that God made the big bang and thereby created theuniverse. Problems with this view are easily spotted, such as how a nonmaterial being managed tocreate matter and energy, but there is something more satisfying about the idea of a creator than aboutthe idea of our universe just popping into existence through some kind of inexplicable quantumfluctuation. Theology still seems more explanatory than does magic.Recently, however, an alternative to both theology and magic has been proposed by twodistinguished physicists, Paul Steinhardt and Neil Turok. They have developed a new theory of acyclic universe, according to which our universe came into existence because of the repeatablecollision between two strange objects called branes. The cyclic model is based on the leadingapproach to fundamental physics, string theory, according to which matter is composed of vibratingstringlike objects operating in more dimensions than the one temporal and three spatial ones familiarfrom our everyday experience. A brane (short for “membrane”) is a multidimensional surface that canmove, stretch, curve, and collide with similar constituents. According to Steinhardt and Turok, ouruniverse began with a violent transition from a low-energy density state to a very high-energy densitystate consisting of the hot plasma that constituted the big bang. The energy produced will eventuallydecay, leading back over a trillion years or so to the state in which a brane collision could produceanother big bang, with repetitions at regular intervals throughout cosmic history, past and future. Ineach cycle, there is a big bang followed by stages dominated successively by radiation, matter, andenergy, leading to contraction and eventually another big bang.Steinhardt and Turok present evidence that the cyclic theory matches all the current astronomicalobservations with the same accuracy as the modified big bang theory, and show how it potentially canexplain and unify some aspects of the universe beyond the range of the big bang theory. No one yetknows whether the cyclic universe theory will become an accepted part of astrophysics, in partbecause it has been difficult to perform experiments to provide evidence that would support theacceptance of string theory, which the cyclic theory presupposes. Nevertheless, I mention the cyclicmodel here because it shows the possibility of an evidence-based answer to the question of why thereis something and not nothing. According to the model, there has always been something, namely,branes, which are the historical causes of the existence of an infinite number of universes, includingours. The main explanation of the existence of familiar things such as the sun, the planets, andmembers of our own species is the big bang history of our universe, which originated through thebrane mechanism that Steinhardt and Turok propose. Perhaps the cyclic universe is not emotionallysatisfying, because it stands far from providing any kind of reassurance about the meaning of theuniverse and our place in it. But it is potentially cognitively satisfying because it provides anonmysterious mechanism by which our universe could have come to be. If I someday write a secondedition of this book, I hope it will have a chapter section called “Branes and the Meaning of Life.”Steinhardt and Turok reject the popular anthropic principle, according to which the complexity ofthe universe is connected with our ability to exist in it as observers, as if the universe were somehowfine-tuned to produce humans. They grant that the physical laws and conditions that govern theuniverse must be compatible with the fact that life exists, but this fact tells us nothing about the originsof those laws and conditions. Some physicists suggest that our planet lies in an unusual universe outof a multiverse of possibilities, finely tuned as a prerequisite for life to evolve. In contrast, the cyclicmodel sees our universe as arising from physical mechanisms, not abstract ideas such as themultiverse and fine tuning to support life.I see the anthropic principle as yet another attempt to stage a Ptolemaic counterrevolution, aimingto put human minds back at the center of reality. This attempt is no more successful than its manypredecessors, including Kant's theory of knowledge, Husserl's phenomenology, Buddhist mysticism,New Age wishful spirituality, postmodernism, the Wittgensteinian defense of everyday concepts, andconsciousness-based interpretations of quantum mechanics. Rejecting idealism and the lure ofdualism, we need to comprehend the insights of physics, biology, and neuroscience that our minds arejust another physical process in a vast universe. The cyclic theory shows how this universe mighthave come into existence through a physical mechanism, without generating spurious reassuranceabout the centrality of human thinking to reality. Only in the past few hundred thousand years, out ofthe many billions of years that the universe has existed, have human minds been around to interpretreality. We have no way of ever knowing whether other kinds of minds evolved in previous cycles ofexpansion before our universe was formed, or whether new kinds will evolve in future cyclestrillions of years from now.The Future of Wisdom
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