How did the universe begin? The scientific evidence points to what may seem to be a surprising answer.
The universe is expanding
In 1929 astronomer Edwin Hubble (for whom the Hubble space telescope is named) initiated a revolution in astrophysics when he verified that the universe is expanding. His observations, now called Hubble’s Law, demonstrate that every astronomical object in the universe is moving away from every other object. It’s the same effect you would see if you tossed a stone into a pond of still water, then observed the wavelets as they rippled outward. Each specific point on a wave is moving away from every other point on the wave as it expands further and further from its origin.
The universe had a beginning
The importance of Hubble’s Law is that it indicates that all the objects in the physical universe started their outward expansion from a single point, just as waves rippling outward reflect the point at which that stone you threw entered the water. In other words, Hubble’s observations of an expanding physical universe show conclusively that the universe had a beginning. Known as the Big Bang, this explosive commencement of the universe at a specific point in time and space is now almost universally accepted as scientific fact.
Will the universe eventually collapse back on itself?
There are two possibilities for the future of the universe. One, nicknamed “The Big Crunch,” is that the universe contains sufficient mass that the force of gravity will eventually arrest the expansion and cause the universe to fall back in on itself. That means the cycle of expand-collapse could repeat forever. Calculations indicate that if the shape of the universe is spherical, it does contain enough matter to bring this scenario to fruition.
The other possibility, called “The Big Freeze,” would occur if the amount of matter in the universe is insufficient to bring about a gravitation-induced re-collapse. This will be the case if the shape of the universe is either flat or hyperbolic.
The latest observations, particularly those from NASA’s Wilkinson Microwave Anisotropy Probe (WMAP) show that the universe is flat. This confirms previous studies indicating that the universe will expand forever.
The beginning of the universe was a one-time, never to be repeated event
So the scientific evidence shows that the universe not only had a beginning, but its beginning was a single, unique, one-time event that has never been, and never will be repeated. Here is how a scientific paper published in the Scientific American of March, 1976 describes that event:
“The universe began from a state of infinite density. Space and time were created in that event and so was all the matter in the universe.”
(You can read the abstract of the paper in The Smithsonian/NASA Astrophysics Data System).
The fact that the universe began from a state of infinite density is extremely significant. The formula for calculating density is
ρ = m / V
where ρ is density, m is mass, and V is volume.
For the value of the density, ρ, to be infinite requires that the volume, V, be zero. (Note that it’s not that the volume was very, very small, even infinitesimal; it had to be exactly zero). Thus, at the moment it came into existence, the universe had finite mass but zero volume, the ultimate black hole.
General Relativity suggests that such an entity, called a singularity, has such unimaginably massive gravity that no matter or light can ever escape. Thus, nothing inside the singularity can either escape itself, or cause anything else to be ejected.
In other words, the ultimate singularity, the universe, could not cause itself to generate that massive expulsion of matter and energy called the Big Bang. So, how did it happen?
The fact that the universe could not cause itself to transition from a singularity to an ever expanding ball of matter and energy requires that there be something external to the universe that was able to act upon it to cause that change to occur.
Centuries ago Thomas Aquinas called that something the “uncaused cause” of creation. He was referring, of course, to God.
So, based on the scientific evidence, how do we answer the question of how the universe began? A pretty good summation of the facts science has revealed was recorded in the first verse of the book of Genesis long ago:
“In the beginning God created the heavens and the earth.”