The reader who has finished The Fabric of the Cosmos: Space, Time, and the Texture of Reality is left with a sense of fascination and bewilderment. Author and physicist Brian Greene seeks to explain to the average reader the fundamentals of space and time and how they interconnect to create the sum total that is the universe itself. Greene also asks questions usually only undertaken by philosophers, theologians (and other scientists): Did something exist before the universe itself?
To tackle these issues, Greene divides his book into five parts. In the first part, he covers the fundamentals of physics by introducing (for those not already familiar with them) Sir Isaac Newton and Albert Einstein. Newton realized that if there were two objects rotating independently of each other (such as a bucket and its contents simultaneously), those individual objects would still move in relation to some larger object Newton could not see. Newton theorized that this object was the whole of space itself. When asked what this absolute space is, Newton gamely replied that absolute space could not be defined because it is already well known to everyone who experiences it. (In other words, Newton did not answer the question at all.) His theories of motion would eventually become the foundation of classic physics.
While Newton's principles applied to the majority of objects that scientists could observe, there were objects that did not behave exactly as Newton's equations said they should. Gravity affects everything, including space itself, and Einstein realized that objects on a grand scale—whole planets, stars, and so on—bend the shape of space around them. Einstein pictured space around these objects as pliant and bending itself around each object in turn. A mosquito on the surface of water will bend the surface it stands on very slightly, while planets shape the space around them on a much larger scale. Phenomena Newton's laws could not explain precisely, such as the planet Mercury's irregular orbit around the Sun, could now be computed exactly with Einstein's general theory of relativity. Einstein's general theory of relativity and his special theory of relativity—that time moves more slowly for an object going faster and faster—shaped the discipline of physics even further.
What Newton and Einstein did for the macro-scale universe, Erwin Schrödinger did for the micro-scale universe. Objects on the subatomic scale, such as atoms, behave very differently than do objects on a macro scale. Schrödinger believed that reality is observed and that, until it is, every reality is happening at the exact same time (later to be known as the Many Worlds interpretation). For example, is a cat trapped in a box alive or dead? According to Schrödinger, until one looks inside, the cat exists in both states simultaneously. To add to the intricacies of quantum physics, Werner Heisenberg realized that the harder one tries to pinpoint the whereabouts of a subatomic particle, the more unlikely one would be to find it. Trying to shine a light on a subatomic object makes it less likely one will be able to find said object, because the light actually has a force that knocks the subatomic particle away. Mathematically, one could only deduce either the velocity or position of a particle but never both. This is known as the Heisenberg uncertainty principle.
In part 2, Greene deals with the concept of time and the way time flows from past to present. This leads to the question of whether physics allows time to flow backward. Through examples ranging from the chicken-and-egg scenario through that of taking the same egg and breaking it on the ground (and reassembling it again), Greene points out that physics does not say that time cannot flow backward. Everyone would agree that time only flows in one direction—from past to future—so the fact that time actually (and mathematically) can be shown to flow backward without consequence is a bit of a shock. Even though Greene says that time can be shown mathematically to flow in either direction, obviously this is not the case, so there must be another element in the works that directs the flow of time.
Dipping back into quantum mechanics, Greene explains that while objects on the macro level may be unaffected, on the microscopic...
(The entire section is 1747 words.)