WLC’s Time, Part 4: General Relativity
When I first began my discussion on William Lane Craig’s ideas about time, I framed it as a debate between two competing models. To briefly recap, Dr. Craig supports the Tensed Theory of Time, which states that events only become real as they occur and that, therefore, the future exists only in potentiality, not in reality. In contrast, he opposes the Tenseless Theory of Time, which asserts that all moments in time– past, present, and future– exist equally in reality, even though we only observe them at the present. In order to support his case, Dr. Craig has offered a genetic fallacy regarding Einstein’s personal philosophy, an assertion which falsely equates Lorentzian relativity with Einstein’s, and complete misunderstandings of the implications of quantum entanglement and the cosmic microwave background. In this fourth installment of this series, I am going to discuss the ideas which Dr. Craig presents about General Relativity, ostensibly as a means of supporting his Tensed Theory of Time.
Almost comically, William Lane Craig’s math and science illiteracy prevent him from realizing that all the evidence which he offers from General Relativity stands in direct and diametric opposition to the Tensed Theory of Time.
Before I address the points which Dr. Craig has made, let me first give a very brief overview of General Relativity. In 1905, when Einstein first published his paper on relativity, he realized that his initial model had a very severe limitation. The math in his paper depended on observers moving at constant velocities, and the model essentially broke down if an observer’s velocity was continuously changing– for example, if the observer was accelerating. Since the model only applied in special cases, scientists began referring to it as Special Relativity. However, Einstein was obviously not satisfied with an incomplete model, however revolutionary it might have been. So, over the next ten years, Einstein worked extremely diligently in an attempt to generalize his Special Relativity to space and time, as a whole. His breakthrough was in the realization of the Principle of Equivalence. Thinking back to Special Relativity, we saw that if we have two astronauts, Buzz and Tom, out on a spacewalk, Buzz might feel like he is totally stationary while Tom is moving away from him, while at the same time Tom feels like he’s at rest and watching Buzz move away. Motion, we concluded, was relative to the observer, and therefore both Buzz and Tom are equally correct in their observations. In thinking about General Relativity, Einstein realized that there is no difference between an observer that is accelerating and an observer that is being affected by gravity. If we take Buzz and place him in a rocket with no windows which is accelerating at , while we put Tom in a similar vehicle which is at rest on the surface of the Earth (whose gravity pulls Tom down at ) both men experience the same effects. Gravity and acceleration are equivalent. This realization allowed Einstein to evaluate the mathematics of the situation far more intricately than had been possible before, and it is this mathematics which had an enormously profound effect on just how it is that we understand Time.
In 1907, soon after Einstein had first published on the Special Theory of Relativity, a mathematician named Hermann Minkowski realized that the best way to understand the implications of relativity was as a 4-Dimensional manifold, a geometrical object wherein three of the dimensions described our familiar 3D space while a fourth dimension described time. In 1917, astronomer Willem de Sitter built upon the foundation of Minkowski space with an interest in better understanding General Relativity. Since that time, the best models of the cosmos have described the universe as a de Sitter space. We now generally refer to this sort of 4-Dimensional view of our cosmos as Space-Time.
Now, we can move on to Dr. Craig’s arguments. He says that General Relativity restores a sort of cosmological perspective to our view of the universe. He notes that space-time, under these models of GR, takes on a sort of hyper-cylindrical shape with three finite spatial dimensions plus one infinite dimension of time. For the purposes of this discussion, it will be helpful to think of space-time like an infinitely long pepperoni before it has been cut into slices. Dr. Craig then states that, while GR does not require any specific method for “slicing” this space-time into units, there seems to be a preferred method determined by the symmetries of the objects involved. Going back to our pepperoni example, you don’t have to slice pepperoni perfectly vertically; but if you do slice it vertically, you get beautifully symmetric circular slices. Similarly, Dr. Craig notes that a certain symmetry can be found in space-time which might lead to a preferred slicing. He then labels this symmetry as “cosmic time,” and concludes that, “cosmic time serves to restore to us our intuitive notions of universal time and absolute simultaneity which [Special Relativity] denied.”
Unfortunately for Dr. Craig, the “cosmic time” which he proposes has extremely little to do with our “intuitive notions of universal time,” nor does it do anything to restore absolute simultaneity. Craig seems to be associating “cosmic time” directly with an incremental invariant interval separating different points in space-time. There is nothing intuitive about classifying such an interval as a unit of time. This is not a depiction of the uniform, monolithic flow which time had been regarded to be, prior to the development of relativity. This is an incredibly complex concept of hyperspace non-Euclidean geometry. For example, think of a photon leaving a star 8 light years away from us which reaches the Earth at the precise moment to be captured by a telescope. Now, using our intuitive understanding of time, we would say that it took 8 years for that photon to travel from the star to our telescope. However, using the definition of “cosmic time” which Dr. Craig proposes, there has been absolutely no passage of time between the photon leaving the star and reaching its destination. That single photon exists simultaneously at every single point along the path which it is traveling, essentially placing a single object in an infinite number of places at once.
However, there’s an even more problematic issue which Dr. Craig doesn’t seem to see. William Lane Craig wants to argue for the Tensed Theory of Time. To do so, he argues against the Tenseless Theory of Time. In order to do that, he needs to show that Special Relativity does not accurately describe time. For that, in turn, he needs to show that there is a “cosmic time” to which inertial reference frames are relative. His support for this “cosmic time” is based upon a 4-Dimensional space-time. However, a 4-Dimensional space-time, by its very definition, requires the Tenseless Theory of Time, since it posits that all points in time– past, present, and future– are extant in reality to act as a coordinate dimension with space. Because he doesn’t understand the science and mathematics which he is trying to cite, Dr. Craig has inadvertently disconfirmed his own supposition by reductio ad absurdum!
William Lane Craig has an overwhelming desire to cling to an antiquated understanding of Time because of his theological concerns. He does not comprehend the math and science behind current understandings of Time. Even worse, he actively misrepresents the science in an attempt to validate his view in the minds of his audience. Elsewhere in his work, Dr. Craig has gone on record as saying that it is “just hugely embarrassing that over half of our ministers really believe that the universe is only around ten-thousand years old,” criticizing this Young Earth position because “scientifically, it’s nonsense.” Yet, when it comes to the subject of the nature of Time, William Lane Craig engages in exactly the same sort of theologically-inspired science denial and misrepresentation that he decries in these literalist Christians. Dr. Craig is not simply taking an unbiased look at the evidence and following to its logical end; William Lane Craig has already decided on the conclusion he wants to find, and he’s trying to twist the evidence to make it fit.
Articles in this series:
- Part 1: Introduction to Time and Relativity
- Part 2: Einstein the Verificationist
- Part 3: Bell’s Theorem and the Cosmic Microwave Background
- Part 4: General Relativity
- Part 5: The Nature of Change
- Part 6: Did the Universe Begin?