Science and the A-Theory of Time
Dr. Craig evaluates a critique of the A-theory of time.
“Science and the A-Theory of Time”
KEVIN HARRIS: Dr. Craig, we’ve interacted with some of the work of Jonathan MS Pearce from time to time. He is a blogger and author; a non-theist. He talks about you and your view of the A-theory of time in this particular article that we are looking at. He cites the work of Counter-Apologist, another non-theist blogger that's pretty popular. They bring up the A-theory of time, and he says that your case for the A-theory is this:
He needs time to be absolute, and not relative as science appears to predict and lead to. This means that there must be something called a privileged reference frame (or similar wording) that everything in the universe refers to. However, science appears to prefer relativity such that time is relative depending on the reference point. If twins live on earth and one twin flies off at near the speed of light and returns sometime later, the two clocks that the twins own and keep on them will show different times. There is no overarching time which dictates both paradigms, but individual and relative times for want of a better explanation.
DR. CRAIG: I was puzzled when he said right off the bat that Craig needs time to be absolute. I thought, “What does he mean by this? That I need time to be absolute?” And I think the reason he thinks that emerges later in the blog where he says, “Craig needs absolute time for the Kalam [cosmological argument] to work.” I think what he's thinking of (in fact, I feel certain about this based on the remainder of the article) is that he is thinking that the A-theory of time needs to be correct if certain arguments in support of the premises of the kalam cosmological argument are to be justified. In particular, the argument based upon the impossibility of forming an actual infinite by successive addition appeals to a view of time according to which events happen one after another – temporal becoming is real, things really come into being and go out of being. And my argument is that you cannot form an infinite series of events by adding one member after another so that indeed that particular argument, at least, presupposes the A-theory of time. The argument against the impossibility of the existence of an actual infinite doesn't presuppose an A-theory of time, and neither do either of the two scientific confirmations that I offer for the argument’s premise that the universe began to exist appeal to an A-theory of time. Those are the expansion of the universe and the thermodynamic properties of the universe. So it's only one argument in support of the second premise that depends crucially on an A-theory of time.
But here's the point. Jonathan conflates the A-theory of time with an absolute theory of time, and that's just confused. He doesn't understand what he's talking about. These are two entirely different things. Einstein's original theory of relativity (special theory of relativity in 1905) denies that there is any absolute time. It's a theory of relativity. But Einstein’s formulation of the theory presupposes an A-theory of time. That is to say, that objects are ordinary three-dimensional things persevering or enduring through time. The original formulation of special relativity theory is relativistic but it presupposes an A-theory of time, not a tenseless theory of time. Einstein had no idea of this idea of a tenseless theory of time. This came in 1908 when Hermann Minkowski gave a four-dimensional formulation of Einstein's relativity theory. When Minkowski formulated in four-dimensional geometrical terms, he presupposed this tenseless view of time – that temporal becoming is an illusion and that time and space are fused together into this entity called space-time which just exists tenselessly. So relativity is entirely compatible with an A-theory of time. The original special relativity theory was an A-theory of time. The Minkowskian view is the view that is relativistic and tenseless – or so-called B-theory of time. The neo-Lorentizian view that I have championed is not committed, as this author thinks, to an A-theory of time. You can give a neo-Lorentzian relativity theory a four-dimensional geometrical formulation just like Minkowski did. You can formulate that in terms of space-time. In fact, you can take Newtonian space-time theories and formulate them in terms of a tenseless four-dimensional geometrical structure. So he's just confused here in thinking that a commitment to absolute time is a commitment to the A-theory of time, and that commitment to an A-theory of time precludes a relativistic view of time. This is all just massively confused. It's clear that he hasn't read, I think, my work on time and eternity much less the scholarly literature, and so he just makes error after error on the basis of this fundamental conflation.
KEVIN HARRIS: He says, continuing,
Now remember, Craig appeals to science and scientists who agree with him about an absolute beginning to the universe such that he lauds such science as supporting theology.
Craig needs absolute time for the Kalam to work . . .
DR. CRAIG: Which I’ve already denied.
But since science does not support this, and appears to support a B-Theory of time, Craig appeals to something called Neo-Lorentzian (NLR) relativity as establishing an absolute time frame. However, NLR is not supported by any scientific data, and nor can it be. It is an unfalsifiable approach.
DR. CRAIG: And the same can be said of Einstein's original formulation of relativity theory in terms of a tensed view of time, and the same can be said of the Minkowskian interpretation in terms of a four-dimensional space-time geometry. All three of these theories are empirically equivalent. They make the same empirical predictions. They all have the same mathematical core, the same equations; they just lend different physical interpretations to them. So which is preferred cannot be decided on the basis of empirical science. They are empirically equivalent, except, here I want to say, very recent work in physics on what's called Bell's Theorem and these so-called EPR experiments do suggest that there is absolute simultaneity in the universe. If you send a photon off in one direction and a photon off in the other direction, these cannot be correlated by any causal signal because they're moving at the speed of light, and that is a limit for causal signals. But if you measure one of those photons with respect to, say, its momentum or its position, the other photon (which is causally inaccessible) immediately takes on the correlated value. Now, how do you explain this? It seems to me and to many theorists, including John Bell himself, that the best explanation is that there is absolute simultaneity in the universe. If you deny that, what you're going to get is causal signals going backwards in time which results in all sorts of pathological sorts of experiments where the effect can come before the cause. Although these theories are basically empirically equivalent, the neo-Lorentzian view actually enjoys a considerable advantage in light of these EPR sorts of experiments involving quantum entanglement. The cheapest solution would seem to be to affirm that there are relations of absolute simultaneity in the universe. So I think there are good reasons for preferring a neo-Lorentzian interpretation of special relativity.
KEVIN HARRIS: Let me chase this just a little bit then because Jonathan really appeals to science and scientists and science does not support this and science doesn't support that. Isn’t most of this a philosophical consideration except with what you just mentioned?
DR. CRAIG: Yeah, he's confused. He’s confusing A-theory of time with absolute time. He thinks that because special relativity theory supports relativistic time (non-absolute time) that therefore it denies the A-theory of time, and that's just wrong. The original special theory of relativity was formulated in terms of an A-theory by Einstein. Moreover, he only focuses on special relativity, but what I point out in my published work is that when you turn to general relativity then absolute time re-emerges on a cosmic scale that was denied in special theory. So the special theory has been superseded by general theory of relativity. In general relativity, there emerges a cosmic time that measures the duration of the universe from its inception. This cosmic time is the same for every observer in the universe regardless of his state of motion. It is not relative to reference frames or motion. It is frame-independent and in that sense absolute, and it measures the absolute duration of the universe. So when scientists tell us that the universe is around 14 billion years old, they're not talking about in Earth time or relative to our reference frame; they are talking of cosmic time which is the time that measures the duration of the universe. This time is not a coordinate. It is a parameter. It is independent of the spatial coordinates of any object. That's what it means to be a parameter. So this is a time parameter that measures the duration of the universe in terms that are not in any way relativistic to motion or location.
KEVIN HARRIS: I wonder what it would be in Earth time.
DR. CRAIG: Well, this is very interesting! Fortunately, the Earth, in its local motion, tends to be very close to the cosmic frame of the expanding universe so that Earth time, in fact, does give a pretty good approximation of what cosmic time is. We are not moving very much relative to the expanding frame of space. Isn't that exciting? To think that our clocks on Earth should measure this cosmic time pretty accurately despite our motion. It just astonishes me.
KEVIN HARRIS: This is the realm of science. Bell's Theorem is an empirical scientific experiment, but they're still philosophical inferences that can be brought about by all of this or can be examined from all of this, as you've pointed out many times. I wanted to mention really quickly – he says:
Craig posits an A-Theory of time based on what? Well, according to the closer to truth videos, Craig adheres to the A-Theory of time because it fits better with the existence of God.
The link is broken here to the Closer To Truth videos, even though I've seen it before, but I went back over them and I really don't know what Jonathan is getting at here.
DR. CRAIG: I think that what I argue is that God is in time because of his relationship to an A-theory of time. The question here is not which theory of time is true; the question is: is God timeless or temporal? I argue that given God's existence and the A-theory of time that God is probably temporal. But if you would ask: why do I think an A-theory of time is true? Well, I give a couple of reasons in the book. One is the inerraticability of tense from human thought and language. I think that human thought and language provides a kind of mirror on the world and that there are tensed facts that therefore require time to be true. The second one is based upon our experience of presentness. We experience the present, and that requires, I think, the objectivity of what is happening now. So those are the two arguments that I give for the A-theory of time. Then I give arguments against a tenseless or B-theory of time, and I have quite a number of arguments as to why that's a less satisfactory view. So there's no circularity as he alleges here in the article. He thinks that I am arguing somehow in a circle.
KEVIN HARRIS: Yeah, he says, hang on!
DR. CRAIG: Yeah, go ahead and read that paragraph for our listeners.
KEVIN HARRIS: He says,
HANG ON!!! [all caps, three exclamation points.] He uses the Kalam to argue to God, but one of his premises in the Kalam requires a prior commitment to God to establish a major building brick which then allows him to posit an unfalsifiable (unscientific and metaphysical) theory which allows him to posit a premise supposedly based on science!
Wow, that is circular and fallacious!
DR. CRAIG: It sounds awful, doesn’t it! But this is just so multiply confused. I do use the kalam cosmological argument to argue to God's existence. But none of the premises of the argument requires a prior commitment to the existence of God because I don't use the existence of God to establish the A-theory of time. Rather, I offer independent arguments for the A-theory of time, and therefore those premises of the cosmological argument that depend upon the A-theory of time, I think, are successfully supported. Even if it weren't (as I pointed out at the beginning of this podcast) several of the arguments for the beginning of the universe don't depend upon an A-theory of time. Finally, he says by having an A-theory of time this allows me to posit an unfalsifiable (unscientific and metaphysical) theory which is the way he characterizes neo-Lorentzian relativity. That's, again, wrong. Neo-Lorentzian relativity is a scientific theory. H. A. Lorentz was a great scientist, and there are several scientists that hold to this interpretation. It's not any more metaphysical than Einsteinian relativity or Minkowski’s space-time. I mean, you want to talk about a metaphysical theory? How about Minkowski’s space-time realism which posits this four-dimensional geometrical structure. It is not true that Lorentzian relativity is in any way more metaphysical than its competitors.
KEVIN HARRIS: Yeah, he's saying that you're punting to metaphysics by using the neo-Lorentzian view.
DR. CRAIG: That’s just silly. That is obviously wrong. And then that it's unfalsifiable – as I explained, it enjoys the same empirical predictions that the original relativity theory did and that Minkowski's theory did as well. And, moreover, this whole business about special relativity is sort of academic at this point because it's superseded by general relativity for which we have excellent evidence and in which we have this cosmic time parameter that is absolute and not related to reference frames. And all of this is based upon the confusion that the kalam cosmological argument requires a denial of relativistic time. That is simply false. You can be an Einsteinian advocate of his interpretation of relativity theory and still believe that the space-time universe had an absolute beginning about fourteen billion years ago. It just doesn't have anything to do with whether you're into relativity theory or not.
KEVIN HARRIS: OK. Well, he wraps up the article by just accusing you of making extravagant claims and unfalsifiable assumptions in order to keep the A-theory of time alive as a live option, as if it's going away. He concludes,
The problem of course, is that so far Einstein and the Standard Model have held up, so Craig is left appealing to his unfalsifiable privileged frame to try and pretend the Kalam is a live option in anything but the minds of people who already commit to god’s existence, or an esoteric philosophy of time.
Is that what you are doing?
DR. CRAIG: That's just nothing but smoke and mirrors based on fundamental misunderstandings of the science involved. The kalam cosmological argument, in some of its supporting substructure, depends on an A-theory of time, but an A-theory of time does not depend upon the existence of absolute time. It's entirely consistent with relativistic time, and so there's no way in which the cogency of this argument is compromised by adopting a relativistic view of time which is, in any case as I say, superseded by what you have in the general theory relativity which is well supported by evidence. So I'm afraid that he needs to go back to the drawing board. He needs to actually read the book and grasp these distinctions before he tries to launch this sort of criticism.
 Total Running Time: 19:47 (Copyright © 2018 William Lane Craig)