[The Big Bang] is an irrational process that cannot be described in scientific terms … [nor] challenged by an appeal to observation. –Fred Hoyle
Contrary to popular public opinion, the Big Bang is one of the most sound, well-tested and verified scientific models of all time. It’s right up there with Evolution, General Relativity, and the Standard Model. In fact, it’s sometimes known as the Standard Cosmological Model.
Let’s remember, however, that unlike Evolution and General Relativity, the Big Bang is relatively new. This is because, until 1929, we thought the Milky Way was the full extent of the Universe! Once we realized that our galaxy was just one of many, and that the farther away a galaxy is, the faster it moves away from us, we realized that the Universe was vast. Rather than just our Milky Way, the Universe consists of billions of galaxies comparable to ours.
When the Big Bang Theory came out, it said that the reason the galaxies are expanding away from us — and that the farther one is from us, the faster it expands away — is because the Universe started off in a hot, dense, expanding state. And that ever since, the only thing that’s really mattered is gravity, pulling matter into structures like stars and galaxies, and slowing the expansion rate of the Universe through gravitational attraction.
In addition, the Big Bang also made two outstanding predictions: the abundances of elements created in the Big Bang and the existence of the leftover radiation from the Big Bang. Both of those have been experimentally verified, and it was the discovery of the Cosmic Microwave Background in the 1960s that led to the general scientific acceptance of the Big Bang and the rejection of practically all other models.
But if you can make another model that explains the abundances of the light elements and the cosmic background radiation, you just might have a viable alternative. Certainly, you’ll have something worth considering. And just last week, a new proposal hit the arXiv. The title?
Sources of cosmic microwave radiation and dark matter identified: millimeter black holes
That’s a novel idea: that millimeter-sized black holes (these would be in between the masses of Pluto and the planet Mercury) could cause the cosmic background radiation! Let’s examine the idea, and see if this is an exciting new possibility, or whether we can demonstrate swiftly and easily that this is not feasible.
So, let’s run with this model. Let’s assume we’ve got these miniature black holes distributed all throughout our galaxy, as the authors assume. They choose the mass of their black holes — m = 4.28 x 1022 kg — so that the Hawking Radiation coming from these black holes is the right temperature to match the cosmic microwave background.
On the surface, this might look good, since the CMB is a blackbody spectrum, which means the energy density vs. frequency graph looks like this.
(Thanks, xkcd.) But there’s another thing that needs to match, that the authors don’t discuss: it isn’t just the shape of the curve, but also the scale. In other words, you need these black holes to radiate enough energy to match the observed energy density!
So what is the energy density of the CMB? It’s about 3 microWatts per square meter. That’s about 300,000,000 times weaker than the radiation we receive at Earth from the Sun. So that might seem like a small energy density, but we need to compare it to what these theorized black holes do. So how much power — in Watts — does each one of these miniature black holes emit?
2 x 10-13 Watts. That’s small, but is it prohibitive? Absolutely. Why? Because these things aren’t in your backyard, they’re distributed throughout the galaxy and the Universe! If you placed them far closer than they’re actually allowed to be — at the same distance that the Sun is from us — it would take more than a whopping 1030 mini-black holes to give us enough power.
Of course, by that time, you’ve gone and exceeded the mass of the Universe. So this idea doesn’t work, and it definitely doesn’t work.
It’s really, really difficult to come up with an alternative to the Big Bang, and if you want one, you need to get the light elements, the expansion, and the CMB correct. Even this paper, which was contrived to give you the Temperature and Energy distribution of CMB, couldn’t even get the overall power to reasonably match what’s observed.
But keep trying, because if there is an alternative to the Big Bang, I want to know about it! Until then, I’ll keep on telling the greatest story ever told, and sharing it with you.