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Is the Universe Cyclical?

Tim Staples

Responding to a caller who posits that certain models of a cyclical universe could do away with the notion of a first cause of the universe, Tim Staples explains why modern physics points toward the necessity of a first cause as laid out by St. Thomas Aquinas.


Host: Colin in San Francisco, California, listening on Immaculate Heart Radio, Colin, you are on with Tim Staples.

Caller: Hey guys, I was excited to hear last week you talking about the Five Ways by Thomas Aquinas. Cy, you and Tim had suggested I read up on him, so I’ve been doing that. My argument would be that the natural universe itself could be self-existent and not need God as a first cause, which I think would divert from kind of where Tim was going last week.

First, I wanted to say that I agree that something has to be self-existent; it may have existed forever or it may have existed for all time, at least. But there’s two ways that the natural universe could do that: the first is a cyclical universe that continually gives rise to itself through a Big Bang, and there’s a number of models that are consistent with the Big Bang and with what we know about things like dark energy that would argue that the universe may be cyclical; the second thing is that time itself and space-time seem to arise in the Big Bang, so there may not be a time before the Big Bang for the universe to have been created if time itself is a property of the Big Bang.

Tim: Okay, sure. Well I, first of all I would say that in order to argue for that sort of the “Carl Sagan expanding and contracting universe,” the problem with that is science, you know, the second law of thermodynamics and the law of entropy still is something you have to deal with. Because even if you did—now I have read physicists who have debunked the whole expanding and contracting universe, simply because there’s not—here, to use an analogy, if I lit a firecracker right here and it blew up, the paper would fly up into the air, and then it would stop and then it would come back down, and why is that? Because there’s this massive dense object called the Earth underneath it that generates an enormous gravitational pull that pulls it back down, right?

Well, when you look at the Big Bang, the universe is–and I think science is pretty much in agreement on this—the universe is expanding, and in fact, surprisingly, it’s actually still increasing in speed, which tells you we’re just getting started, and it’s 13.7 billion years ago, and we’re just, the Big Bang is so unbelievable that we’re still in the acceleration phase right now. But eventually it will slow down, and the problem is, even taking into account alleged dark matter and such, there’s simply not enough density for the universe to contract again. You know, at least this is the argument that physicists are making. It just can’t do it.

But even if it could, the second law of thermodynamics does not pass away. Still, you would have entropy, and that means, as you know, Colin, there is less—there’s—you know, there is a certain stated amount of usable energy at the beginning of the universe. And that amount is going down. Well, entropy is increasing, which means the amount of usable energy is not there anymore, it’s dissipating.

And that doesn’t go away because you have another Big Bang; it still is going away, and so ultimately that demonstrates, I think, as Cardinal Ratzinger points out in his book “In the Beginning,” that you have to trace it back to a beginning in time, and you cannot look to the material universe, then, as being eternal. It simply cannot be. That’s contrary to science.

So I do think the problem is, Colin, and I’d like to get your thought here, is that you can’t have a material thing being the first cause, because by nature material things have beginnings. Everything in the material universe that we know—in fact, Colin, this is a principle of science; whenever we look at a galaxy, a star, a planet, one of the first things scientists ask is, “Well, how old is it?” And “How can we demonstrate how old it is?” And scientists have lots of different ways of dating, and so we know that material things cannot be that first cause, because everything that we see in the universe has a cause, is caused by something else. Again, that’s a principle of science.

And so there must be, the argument goes, Colin, a first cause that itself was not caused. The universe is demonstrably caused. It cannot be eternal. And again, that’s scientific principles here. And so there must be a first cause that itself is not caused, and therefore would be the cause of all things and yet not caused. Now if it’s not caused, that means it is in fact eternal.

Now Colin, there are certain things we can know about that first cause, like namely: could never die; could never move from ignorance to knowledge. Why? Because in order to move from what Thomas Aquinas would call a potential to an actuality, or potency to act, you must be acted on by something else that already has that perfection. Well, the first cause could not have, by definition, any of those potencies. It must be—and I’m diverting here, Colin, into Thomas’ first proof—it must be pure actuality, or else it’s not the first cause. Pure act; that means it can’t move from potency to act, can’t move from ignorance to knowledge, can’t even move from here to there, because it’s impossible. Why? Because it’s already there.

So at any rate, Colin, I don’t know if I got to your second point, but are you following me?

Caller: I’m worried that I might have a better understanding of this then you may. I suggest you look at the cyclical models of the universe that have come since our knowledge that the universe is currently expanding. Wikipedia is a good place to start for that. There’s models like the Baum-Frampton model that saves for a certain way of conceiving of dark energy; you could have a big rip, so the universe could expand outward, but get to the point where space-time itself rips, and because everything’s so spread out, you don’t actually have entropy, and you could have another big bang, because you need particles, you need matter to be close enough together to actually have an increased state of entropy. If they’re so spread apart that they can’t communicate with each other, because they’re over the event horizon, and that issue actually goes away, so there’s—

Tim: But Colin, I think you’re not answering a very important point, though. Because everything that you’re saying presupposes that you have particles and such that are in motion. And if in fact those particles are in motion they cannot be the first cause. Because that means they have potency, and in order for something to move, it has to, from potency to act, move from potency to act, it must be moved by something that already has that actuality. So there must of necessity be that first cause, that unmoved mover, that is in fact pure actuality.

So when you’re talking about a Big Bang, the motion of particles, that you’re talking about, a rip, etc., you’re talking about things that have to be caused, have to be placed in motion, by another. So again, this gets back to St. Thomas’s first proof, which demonstrates that in order for all of those things to exist that you’re talking about, there must be the first cause, the unmoved mover, that itself is pure actuality. Pure and infinite being. Absolutely one, absolutely simple.

Caller: I think we’re gonna have to part ways there, because with a cyclical universe that continually goes through the same cycle, that could conceivably have existed in and of itself without a starting point; in fact, the fact that it’s cyclical would infer that it could always have existed in cycles, even though everything and it’s moving. And if you want to look at something that…and if you look at something like the revolution of one planetary body around another, that’s something that’s so stable that it could continue infinitely. So I’m gonna have to disagree there, but—

Tim: Yeah that’s not—but I appreciate that Colin, but what you’re saying there is not science. That’s more science fiction. Because there there’s no such thing in science as perpetual motion. Everything that is—I mean, again, this is, this gets back to Newtonian physics, but everything that is in motion was placed in motion by another that is already in motion. And so again we get back to Thomas’ first proof for the existence of God. I think actually you’re demonstrating our point, Colin.


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