googlef87758e9b6df9bec.html A Sure Word: Exotic Cosmology Part 1: The Balloon Model of the Universe

Friday, July 25, 2014

Exotic Cosmology Part 1: The Balloon Model of the Universe

Imagine for a moment a very large, flat meadow of grass with a crowd of people standing in it. You are somewhere in the crowd. Through just simple observation, it would not be hard to guess where you are in the crowd. If all the people are on one side of you and no one on the other, you would be on the very edge of the crowd. If there were more people on one side than the other, you would be toward the edge. If there were about the same number of people everywhere you looked, you would be closer to the center. It's not hard, right?

As we look around in the universe, we observe about the same number of stars no matter which direction we look. Just as in my crowd analogy, it would be very reasonable to conclude from this observation that we are somewhere near the center of the universe. Of course, the universe is very, very large and since we cannot see the edge of it in any direction, it makes it hard to be sure that we're in the center. It would be like being in the ocean with no land in sight; you would really have no idea if you're in the middle of the ocean or just outside sight of the shore. To really know we're in the center, we'd have to have more information.

In the mid-19th century, Dutch physicist, Christian Doppler noticed that sound waves changed frequency relative to the observer when the source was in motion. He dubbed this phenomenon, “the Doppler Effect” and believed it would apply to all waves including light and radiometric waves. In the beginning of the 20th century, we were able to observe this phenomenon in the light from distant stars. The light from the stars was “redshifted” indicating that the light wave was being stretched and that the star was moving away from us. As we began to survey more and more stars, we realized that the stars uniformly seemed to be moving away from us at a constant speed.

The implications of what was being observed was huge. Obviously it meant the universe was expanding but more than that, the general movement of the stars directly away from us further seemed to confirm our position near the center of the universe.

To help visualize this, let's go back to my crowd analogy for a moment. If everyone in the crowd – including you – began running away from the center, you would notice a couple of things. Someone running right next to you at the same speed would barely seem redshifted at all. However, someone who was running in the opposite direction would be moving away from you very rapidly so would appear highly redshifted (see my illustration). If we were anywhere else but the center of an expanding universe, this is how the redshifts of different stars should appear to us.

Now imagine you were in the center of the crowd and everyone was running directly away from you. As they got further away from you, they would also move further away from each other, but each runner's redshift in relation to you would be approximately the same. This is exactly what we observe. So the simplest explanation (and most secular scientists claim to prefer the simplest explanation) is that we occupy the unique position of the center of the universe.

In this enormous universe, the odds of us coincidentally being in the center are mind numbingly small. I'm not sure how to describe how impossible it seems. I read one source that estimates there are 1 septillion stars (1024). So that would mean the odds of our star being in the center would be 1 in 1,000,000,000,000,000,000,000,000. It would seem impossible if we believed were here by mere chance.

If God had intended us to be in the center of the universe, then the remote odds of it happening randomly don't matter. However, scientists, because of their bias toward natural explanations will not allow themselves to consider that we're here by design. Still, accepting that we occupy this special place by mere coincidence is too incredible to believe. So what is the solution?

Scientists have put forth a model of the universe where there really is no center – or rather everywhere is the center. Space is like a flat surface that is being stretched. All points on the surface would be moving away from each other. They also suggest there is no edge to the universe. Instead, space is curved like the surface of the earth and if you started in one direction and headed in a straight line, you would eventually end up where you began. In other words, no matter where you are in the universe, we would observe exactly the same things that we observe on earth.

To help visualize this strange explanation, many people have compared the universe to the surface of a balloon painted with stars. As the balloon expands, all the stars would move away from each other at about the same rate. Also, any point on the balloon would have the same amount of surface surrounding it so no particular point is the center. It's actually a very clever analogy that paints a vivid picture of the theory it attempts to explain. And the theory seems to cleverly explain how we can look like we're in the center of the universe yet not really be in the center.

No matter how clever the analogy, there is still one, huge, nagging problem I see with it – namely, the balloon really has three dimensions. To believe that the universe somehow exists on an immensely curved plane resembling just the 2D surface of a balloon seems a stark contrast to everything else we experience. It seems an unnecessarily complicated solution, especially when we know a much simpler explanation exists.

In my crowd analogy, if I saw the same number of people on every side of me, I would conclude that I was close to the center. I could test that theory by walking to the edge and seeing if I was right. However, if I had no way to walk to the edge, I would simply have to trust my conclusion as being reasonable. What I believe is unreasonable is if I suggested there really is no center to the crowd and if I tried to walk to the edge, I would eventually end up where I started. Such an idea seems insane. Yet scientists would have us believe that is the correct way to view our universe.

Does the universe have an edge or not? Does the universe have a center or not? The problem with either theory is that we can't really test it. There's no way we could fly to edge of the universe to see if it's there. We can't stand back from the universe and see if it resembles the surface of a balloon. We can only picture the universe based upon we can observe from the earth. What I'll do instead is appeal to what seems the most reasonable explanation.


Steven J. said...

Your argument seems to be more with the Copernican principle of mediocrity than with an old universe as such (i.e. we could be at the center of a very old universe where various sorts of large-scale evolution had occurred).

Please note that the analogy is a dimension short: if space is curved, it would not be a two-dimensional surface curved through three-dimensional space, but a three-dimensional volume curved through a fourth spatial dimension (or, if I understand the cosmologists, three-dimensional space just acts as if it were curved through such a higher dimension). Of course, a further problem is that space does not seem to be curved, or is curved only very slightly and negatively (that is, not like a hypersphere but a hyper-saddle-shape). Or such is my understanding. Again, remember that the balloon image is an analogy; it does not necessarily adequately capture every aspect of the theory it illustrates.

How big is the universe? Intrinsic in the idea of a finitely-old universe with a finite speed of light is the idea that some things can be too far away to be seen. Implicit in the idea of an expanding universe with these properties is the idea that some things may be too far away to ever be seen: the universe might be expanding faster than their light is reaching to us (again, this is not an epicycle: it is implicit in the bare bones of the expanding cosmos idea).

If the universe is infinitely large and expanding, then [a] there would be no true center but every place would appear to be in the center and [b] we could not see an infinite number of stars because most of them would be too far away for their light to have reached us yet (or, depending on the rate of expansion, perhaps ever).

A couple of recapitulated points: first, I did not actually claim that creation was an "exotic theory." My point was explicit: modern creationism contains "epicycles" of its own, to account for, e.g. our ability to see things more than ca. 6000 light-years away, and the idea that the universe is ca. 13.8 billion years old explains these things more parsimoniously. Carvin is arguing basically the same thing about biology: you need epicycles -- features not implicit in creationism as such, but added just to reconcile the idea to the data -- to explain, why carnivores have so many adaptions to eating other animals.

RKBentley said...

Steven J,

I understand the concept of curved space but was a little uncomfortable trying to describe it. You will note I said, “the universe somehow exists on an immensely curved plane resembling just the 2D surface of a balloon...” You're certainly aware that the balloon analogy is not mine originally; it was how your team chose to describe it. I try to visualize it something like the surface of the earth: we exist on the surface in 3D. We don't notice the curve because the earth is so large (from our perspective). If we want to travel from the US to Australia, we have to travel around the curve of the surface. If the earth itself wasn't in the way, we could make the trip shorter by traveling directly through the earth. So the surface of the earth is how some scientists understand space and the space through the earth would be a sort of 4th dimension. Does that make it any more clear?

Having said all that, though, I repeat that it's unnecessarily complicated. Why resort to curved space and a “4th dimension” when a much simpler explanation exists? Isn't simpler better? Isn't that what Occam's razor would tell us?

God bless!!


RKBentley said...

Steven J,

I'm rushed as I answer these and I forgot one point.

You said, “If the universe is infinitely large and expanding, then [a] there would be no true center but every place would appear to be in the center and [b] we could not see an infinite number of stars because most of them would be too far away for their light to have reached us yet (or, depending on the rate of expansion, perhaps ever).”

That would all be true of an infinitely large universe. However, if the universe has been expanding for a finite amount of time, then there has not been enough time for it to become infinitely large no matter how fast it has expanded.

But that is not the point anyway. Your side isn't proposing that it's infinitely large. They're saying it's finite yet without a center or edge.

God bless!!


Steven J. said...

RKBentley, "my side" doesn't start with a preconceived and unalterable conclusion (okay, technically, neither does yours -- otherwise, you'd still be arguing that the sun orbits the Earth -- but you think you do). There are indeed cosmologists who argue that the universe is, or might well be, infinite in extent (they don't seem to think that the speed of light is a problem, presumably because space can expand faster than matter or energy can move).

Note that the reason you can't can't tunnel through a fourth spatial dimension (e.g. to cut travel time to galaxies billions of light-years away) isn't quite the reason you can't tunnel directly from Uruguay to North Korea. In the latter case, at least you'd know which way to dig, but where would you point if you were asked to point in a direction 90 degrees from north-south, east-west, and up-down?

The trouble with Earth as the center of the universe is that it isn't even the center of the solar system, or the galaxy. Once it looked as if we were the first, and in the early 20th century it looked as if we were the second, but we weren't. Just because it looks as if we're in the center of a finite, bounded universe ... "we won't be fooled again." Also, I think you're confusing parsimony (the sort of simplicity sought by scientists, in which one minimizes the number of causes for which one does not have solid evidence) with "easier for me to understand."

RKBentley said...

Steven J,

The problem with an infinite is not just the speed of light. It doesn't matter if space could expand 1,000,000 times faster than the speed of light. You can't start at zero and reach infinity not matter how fast you go. That would be like believing you could count to infinity in 15 billion years because you can count numbers really fast.

And, again, I understand the concept of the 4th dimension (assuming we're not discussing “time” as the 4th dimension). Do you still think I don't get it? I just can't make a perfect analogy of a 4D universe using 3D objects. Of course you can't dig through the alleged 4th dimension the way you might try to dig straight through the earth. But wouldn't the simple fact that we don't how to enter the 4th dimension cause a reasonable person to question if it's really even there? What SCIENTIFIC evidence do you have for it? We obviously can't observe it. Is it only our seeming unique position in the universe? Well, there's a simpler explanation for that which doesn't have to resort to epicycles, phlogiston, or an unobservable 4th dimension.

Finally, I do mean to say that our solar system appears to be in the center of the universe. I know I continuously say “we” but you will notice that I also mentioned in the post “our star” (AKA the sun) being in the center.

Thanks again for your comments. God bless!!