RSS Feed
iTunes Link

Episode 134 - Big Bang Denial

Download the Episode

Recap: The Big Bang is the model that is used to explain what happened just after the origin of the universe. No more, and no less. But there are different kinds of arguments that people make to argue that the Big Bang never happened. In this episode, we go through some of these arguments and the arguments made by scientists to support Big Bang cosmology.

Additional Materials:

Episode Summary

Claim: The Big Bang is the model that is used to explain what happened just after the origin of the universe. No more, and no less. What happened before it, what caused it, and what happened to the universe after it are all different things, though people who argue against the Big Bang almost always conflate them into the same thing. This is similar to how anti-evolutionists will try to stump people with abiogenesis — the origin of life from non-life — not realizing that abiogenesis has nothing to do with evolution. Big Bang denial often takes one of three forms: People just don’t believe it, young-Earth creationists or creationists in general don’t believe it because they cannot reconcile it with their divine being, or people don’t like some other aspect of cosmology and link it to the Big Bang, therefore saying the Big Bang is wrong. I’m going to address each of these, not in that order, and then talk about the evidence for it.

Argument from Personal Incredulity

[Clip from Coast to Coast AM, June 11, 2015, Hour 3, starting 27:33]

“I still will not accept the fact that some minute little particle was compressed so much that it exploded into everything we have today in the universe. I-I-I just don’t get it! Do you?”

Let’s start right off the bat by getting this out of the way: The argument from personal incredulity does not hold any weight. Except when I’m on young-Earth creationist websites, the vast majority of what I hear and read with respect to Big Bang denial is they don’t believe in the Big Bang is that they can’t understand how it could have happened, or how various parts of it could possibly be real, like how everything could be crammed into an infinitesimal point, or other aspects that I’ll get into.

Without offering any evidence for why, they simply say it couldn’t work because they don’t believe it. That is not a good reason, and it’s one of the more frustrating ones for me because it just shuts things down. By the same token though, it’s easy because there’s no where to go with it, so you can just leave the conversation.

One of the main tenets of science is to remove your own biases and beliefs from the system to determine what is the most likely scenario, regardless of whether it makes sense to you personally.

Not Believing in Different Cosmological Ideas that Aren’t the Big Bang

The second most common objection I hear to the Big Bang is statements along the lines of:

Well, what started the universe?

How could the universe have been so small?!

Inflation violates relativity.

There are metal-heavy old stars but according to the Big Bang, there shouldn’t be because metals didn’t exist back then.

Dark Matter is fake, therefore the Big Bang is fake.

And other kinds of things that have one aspect in common: They have nothing to do with the Big Bang. As I stated in the intro, the Big Bang is the cosmological model that describes what happened almost immediately after our universe came into existence. By “almost immediately,” I’m talking about 1 Planck Time, which is equivalent to about 5 x 10-44 seconds. That’s the unit of time that it takes light to travel a Planck Length in a vacuum, equivalent to about 2 x 10-35 meters.

It’s a very very tiny amount of time, but it’s important nonetheless because it means that the Big Bang model does not describe what started the universe. It does not describe how the universe evolved afterwards. It does not describe star formation or heavy element formation. Those are all other cosmological ideas and they have their own models - some more speculative than others - and while they are all tied together into a macro-model of the universe, lack of understanding about one does not mean all the others are false.

To use one of my famous contrived analogies, I’ll describe what I did today. I went to bed around 12:30am, I woke up around 8:30am, I checked my e-mail in bed, turned off my alarm for 9:30 and got up at 9 for a telecon, did that for an hour and a half, went back to sleep until 1:00, worked for another few hours, then wrote this podcast episode, had dinner, then recorded the episode.

I don’t remember exactly what I did from 10:30 until 11 am. I don’t know the exact neurological process that let me sleep. I don’t remember how often I hit the snooze button or to what time I set my alarm clock to get me up at 1, originally. I don’t remember what I had to eat other than my recent dinner.

All because I don’t remember or know the specifics of those things, that does not mean that today didn’t happen for me. Or that I didn’t wake up today. Similarly, all because we may not know specifics of certain cosmological processes, that does not mean that the Big Bang model is wrong.

Young-Earth Creationist Objections

Next up are the young-Earth creationist - or even old-world creationist in general - objections. For the old-world creationist, the only objection I’ve heard is that the Big Bang is man’s attempt to explain what God did with a thought.If that’s your world view, nothing I’m going to say will change that, but to be honest, it also doesn’t matter to me. I do think that the science is perfectly reconcilable with the old-world religious view because you can simply attribute the Big Bang to the mechanism that your deity used. But that’s your choice to believe that or not.

For the young-Earth creationists, or “YECs” for short, there are of course many objections. None really address the science nor the evidence for the Big Bang, which I’ll get to momentarily. Rather, they follow the classic YEC tactic of starting with the answer, then then rejecting anything that conflicts with it.

Scientists say that the Big Bang happened about 13.8 billion years ago? Well, obviously that’s wrong because Bishop Ussher showed that the Biblical chronology indicates the universe is about 6000 years old.

Scientists say that Earth wasn’t formed until nearly 10 billion years after the Big Bang? Must be wrong because the Bible says in Genesis that God created Earth on the first day.

Or that the Big Bang cosmology indicates there’s no center of the universe, but the Bible is interpreted such that Earth is the center, or at least the sun is the center, having moved there in 1992 when the Pope forgave Galileo.

And it goes on like that. In the shownotes, at podcast.sjrdesign.net, I’ve linked to a few blog posts of mine from several years ago that I wrote about YEC claims about the Big Bang, if you’re interested in reading them.

This isn’t going to be an episode where I’m going to pick apart the YEC arguments, because they really don’t argue with the science, they argue from the Bible as the starting point. It’s really the same as the first kind of Big Bang denial: They simply can’t believe it because they believe something else that they interpret as directly conflicting with the Big Bang. This isn’t a case like in Episode 112 where I could go through and show how a YEC was misusing the science to claim Mercury is young, or comets in episode 3. It’s just flat-out denial.

Overview of the Big Bang Model

So let’s get on with what the Big Bang model actually suggests, and then talk about the four main pillars of Big Bang cosmology.

Taking a page from The Reality Check podcast [insert page turn], I’m going to quote from Wikipedia on this, because it’s written very well:

“Extrapolation […] of the universe backwards in time using general relativity yields an infinite density and temperature at a finite time in the past. This singularity signals the breakdown of general relativity and thus, all the laws of physics. How closely we can extrapolate towards the singularity is debated—certainly no closer than the end of the Planck epoch. This singularity is sometimes called "the Big Bang," but the term can also refer to the early hot, dense phase itself, which can be considered the "birth" of our universe. Based on measurements of the expansion using Type Ia supernovae, measurements of temperature fluctuations in the cosmic microwave background, and measurements of the correlation function of galaxies, the universe has an estimated age of 13.798±0.037 billion years. The agreement of these three independent measurements strongly supports the ΛCDM model that describes in detail the contents of the universe.”

That last line is a bit beyond the scope of this episode, but it basically means that completely different methods of trying to figure out what the universe is made of pretty much say the same thing.

There are other parts of the cosmological history of the universe that are frequently tacked onto the Big Bang. As I’ve tried to make abundantly clear, I disagree that these are considered part of the Big Bang model. They are consequences of the Big Bang, and what we think happened during different epochs in the universe’s history as a consequence of the Big Bang. It’s because of that, though, that we can start to understand the four main pillars of evidence that the Big Bang happened, and it happened in a way consistent with the different models that describe each phase of the universe’s history that happened after it.

Pillar 1: Everything’s Moving Away

The first pillar of the Big Bang theory is the objective observation that at large distances, everything is moving away from us. This is measured primarily from the shift in light as it gets stretched out from its motion away from us. This has been interpreted to mean that the fabric of the universe itself, in which galaxies and everything else exists, is expanding and taking things along for the ride. This is also location-independent and doesn’t mean we’re at the center of the universe: From ANY observation point, at large distances every object is moving away.

The reason that local objects like the moon, or the sun, or the galaxy, or neighboring galaxies are not moving away is that the strength of this universal expansion is less than the strength of the gravity keeping us together. But, at larger scales, gravity is overwhelmed and the universe’s expansion takes over.

This has been objected to by some YECs as a pillar of the Big Bang model because they point out that it was discovered in the 1920s and ‘30s, before the Big Bang model was theorized. I’ll forgo my typical decorum on this show and point out that this is a really stupid argument. Just because I observe the sky to be blue, and only later learned that it’s nitrogen in the atmosphere that makes the sky blue, that doesn’t mean that the air can’t have nitrogen because I observed the sky to be blue before I knew about nitrogen.

The observation that the universe is expanding is a pillar of the Big Bang because, just as the Wikipedia article quote pointed out, if we see things expanding now, then if we run the clock backwards, stuff moves closer together. And, one could reasonably hypothesize that at some point in the past, everything was crammed into an infinitesimally small point, a singularity.

But, we don’t even need to “go there,” as the saying goes. We can stop three sentences ago and point out that the current expansion of the universe is precisely predicted by a model that says stuff started closer together and moved farther apart as it aged. As opposed to other prevailing models at the time that pretty much were steady-state: The universe had always existed in its current form, or some close variation of that.

Pillar 2: The Cosmic Microwave Background (CMB) Radiation

While the Big Bang was formulated in the 1940s and 1950s, one of the predictions made in 1948 that was made based on it was that there should exist this thing called the Cosmic Microwave Background, or CMB, or Cosmic Microwave Background Radiation, CMBR. I tend to use CMBR because when you talk with geophysicists, CMB means the core-mantle boundary and things get very confusing.

The CMBR was supposed to be a background radiation field that permeates the universe. It would have come about because the Big Bang model predicted the universe’s earliest phase was opaque, where it was so dense that no light could not move about without being scattered from free charged particles, like protons. If the Big Bang model were correct, then it would only be after the universe had cooled enough from its initial state that neutral hydrogen could form, and photons could stream freely throughout it. This happened about 380,000 years ago.

This process of neutral hydrogen forming is called “recombination,” and the photons being able to finally move around is called the “surface of last scattering.” This quote-unquote “surface” should show up as a steady, constant glow throughout the universe, that would be practically the same in every direction. The only differences within it would be caused by recombination not occurring at exactly the same time everywhere, due to tiny fluctuations in density and other things.

Most people who are fans of astronomy know what happened next: 16 years later, Arno Penzias and Robert Wilson were working with a microwave telescope and could not figure out why they were getting a persistent noise in their signal. It made no sense, so they asked some astronomy colleagues for help. And it was then that they were told of the prediction that there should be a persistent background noise, corresponding to a temperature of about 3 Kelvins, based on predictions from the Big Bang model.

For their discovery, Penzias and Wilson earned a Nobel Prize in physics in 1978.

To be blunt, I’ve never really seen a YEC response to this, so I went to the bastion of critical thinking, Conservapedia, to see what they claimed. Here’s what they wrote:

The scientific version of events doesn't make sense when viewed from a Christian perspective, as it requires the universe be at least 380,000 years old for the transition to have occurred. However, scholarly analysis of the Bible indicates that the universe is around 6000 years old, which is backed up by many observations in many fields from geology to astronomy.

A possible explanation for the CMB is that it is the light (Genesis 1:2) from the moment of the Creation around the universe. If the Lord had suddenly created the universe and flooded it with perfectly uniform light (electromagnetic waves), we would indeed see the remnants to this day, except for minuscule variations introduced by a fraction of the light being blocked by the Earth (which of course preceded the light, Genesis 1:1).

So, there ya go.

Pillar 3: Big Bang Nucleosynthesis

The third pillar of the Big Bang comes from a prediction made in the 1940s, just about the same time the CMBR was being predicted. A consequence of the Big Bang would be that the universe was really hot early on, and as it expanded, it cooled. A prediction based on exactly how this cooling happened, is that the universe, for all intents and purposes, was like a star. The entire universe, one big core of a star. From the period of about 10 seconds to 20 minutes after the Big Bang, anyway.

During that 19 minutes and 50 seconds period, the entire universe was cool enough, yet hot enough, and dense enough but not too dense, to allow protons and neutrons to combine to form deuterium. From there, there are a few different pathways to make tritium (hydrogen-3), helium-3 or -4, lithium-7, or beryllium-7. The nuclear pathways to make these different elements are extremely well understood in this post-atomic era after WWII in which we live. They depend on a few things, like temperature and density and pressure.

What makes this a pillar of the Big Bang is that if we were in a steady-state universe, then as we look further back in time by looking farther away from us, we would expect to see heavy elements regardless of how far back in time we look. We don’t. We see lighter and lighter elements. In the oldest stars and the oldest galaxies, we see very, very few heavy elements, indicating that the bulk composition of the universe has changed over the last 13.8 billion years (minus 10 seconds), which is at a fundamental level what you would predict if the universe had a finite beginning.

But beyond that, this is a pillar for the additional reason of the relative abundances of these 8 different atoms and isotopes. As I said about a minute ago, the pathways to make these atoms and isotopes are very well known in atomic physics, and so we can - and they did - make specific predictions based on the Big Bang model for what the ratios of these elements should be after the universe was 20 minutes old. Because the universe’s composition wouldn’t change until the first stars had seeded it with heavier elements, we can then go and measure these abundances by making careful observations of the oldest stars, and the oldest regions of the universe.

And, what has been found matches the predictions based on the Big Bang model. They’re also independent of dark matter and dark energy, which will be subjects of future episodes.

What they didn’t match, however, was the relative abundance of lithium-7: It was consistently measured to be 2.4-4.3 times lower than what was predicted originally. So, what does that mean for the Big Bang? Nothing. What it does mean is that the big bang nucleosynthesis models were revised and based on new nuclear physics data for how protons may have interacted with each other in the first few minutes of the Big Bang, the new predictions much more closely matched the lithium-7 abundance.

I’ve said it before and I’ll say it again: That’s how science works. In this case, we had a prediction based on a model based on a model. We tested that prediction. Much of it matched the observations, but some didn’t. We were able to revise the model based on the other model, and based on new data from other observations, and now the predictions from the revised model match the observations.

Pillar 4: Large-Scale Structure

I’ll be honest: When I learned this fourth pillar back in 2004 in my astronomy class taught by Prof. Mihos (that’s a reference back to last episode with Bob Lazar), I wasn’t convinced. Now, 11 years later, I’m coming back to it and re-learning it, and I’m a little more convinced - perhaps because it includes more things than Prof. Mihos focused on because he’s a galactic astronomer, but I still like the first three the best.

The fourth pillar of the Big Bang is the evolution and distribution of galaxies, the growth of large structures, and overall “aging” in the universe. At a fundamental level, this pillar can be thought of as, “Stuff today looks older than stuff in the past, in ways predicted by an evolving universe that had a beginning roughly 14 billion years ago.”

One part of that is that stars that form today are observed to have heavier elements in them than the oldest stars. Though that has more to do with Pillar 3.

Another part of this is that as we look to the earliest parts of the universe, we don’t see large structures of galaxies, only smaller, isolated ones. Galaxy clusters and superclusters seem to be more recent, which is what one would predict as a consequence of a universe with a beginning that expanded out from a point. This is also why when astronomers discover the oldest or the farthest supercluster, it comes with the obligatory tagline of “challenge for the Big Bang.”

Wrap Up

But, these aren’t fundamental challenges to the underlying theory. None of these are consistent with a steady-state model which is pretty much the only proposed alternative.

But there are assumptions built into it. For example, we assume that the physical laws we observe here exist elsewhere in the universe. Meaning that something like big bang nucleosynthesis - the third pillar - only makes sense if atomic, nuclear, and particle physics behaved the same way 10 seconds to 20 minutes after the Big Bang as it behaves today, and it behaved that way everywhere.

Another assumption is the Cosmological Principle, which states that on the largest scales, the universe is homogeneous and isotropic, basically meaning it’s the same. That way, an observation we make about galactic structure when we look in a certain direction should apply when we look in a different direction. And, while those are assumptions, we have tried to test them. So far, they’ve held true.

Which also means that, so far, the Big Bang is still the best model that we have to explain what happened right after the formation of the universe. The predictions and models that come out of it, like inflation, evolution of structure and elements, behavior of light, and other things that are built on top of it, have also been shown to be generally true, but acceptance or non-acceptance of any one of them does not mean that the underlying concept of the Big Bang - that the universe had a beginning - is wrong.

Provide Your Comments: