What Was the Spark That Ignited the Big Bang?

As a child I discovered the world of science fiction and was hooked for life. By the time I started college, I had read nearly all of the sci-fi books in the Brooklyn Public Library. Isaac Asimov was one of my favorite sci-fi authors. In 1956 he wrote the story that he considered his finest: The Last Question.

The Last Question asks what will happen to humanity when the universe finally runs down, trillions of years from now. It was one of the first stories that used the word “entropy” to describe the irreversible process of ordered things becoming disordered.

Astrophysicists tell us that the downhill slide from order to disorder will eventually result in the “heat death of the universe.” The iron laws of physics require sources of energy at different temperatures to do useful work. The “heat death” is a situation where all the energy in the universe is still present but unusable because it’s all at the same temperature.

In Asimov’s story, which spans trillions of years, humanity builds increasingly powerful planetary-size supercomputers and asks them whether it is possible to reverse entropy and save our species. These computers never provide an answer, claiming there is not enough information. Only when the heat death finally occurs, does the one remaining supercomputer assesses the situation and utters the words: “Let there be light.”

The Primeval Atom

The Last Question speculates that it was a supercomputer that created the spark which ignited the Big Bang — or to be more precise, that humans and our inventions continually create the universe anew. It’s an intriguing proposition but there are many competing theories as well.

In 1927 the Belgium astrophysicist George LeMaitre hypothesized that an expanding universe could be traced back in time to a single point, which he called the “primeval atom.” This idea flew in the face of the “steady state model,” the accepted description of the universe as being without a beginning or end.

Astrophysicists now believe that there was an explosion that started our universe about 13.7 billion years ago. They named the explosion the Big Bang.

We have no idea what happened before the Big Bang, or even if there was a “before.” We don’t know what the spark was that caused it to explode. We don’t know if the Big Bang was a unique event, although current thinking is that it may have happened an infinite number of times.

We have, however, arrived at a remarkably detailed understanding of the critical steps in the process of creation of our universe. Understanding just what happened after the Big Bang can give us clues to what might have happened before it.

Inflation Theory

In 1979 Alan Guth, an astrophysicist, suggested that the universe started when a tiny speck of matter, about 1 gram or .035 ounces, exploded. Guth did not know where this piece of matter came from, or why it started to double in size and kept on doing that until it filled the universe. He called this process “inflation.”

Inflation theory claims that our infant universe grew to be immense in a tiny fraction of a second. When the Big Bang occurred, the original one-gram mass doubled in size every 10E-36 seconds. Written out, you can see how infinitesimal an interval of time this doubling period actually is:

1/100,000,000,000,000,000,000,000,000,000,000,000,000 of a second.

After only 260 doublings, the universe reached its present mass, with 1 gram becoming 10E77 kilograms.

A Dense Plasma Fog

For the first 340,000 years after the Big Bang, the universe was too hot for atoms to form. It was filled with a uniform glow from the white-hot fog of hydrogen plasma. NASA physicists have calculated that in the very early stages of the universe, when it was just one-hundred-millionth the size it is today, its temperature was nearly 300 million degrees above absolute zero.

Atoms could not survive in this environment and were broken into protons and electrons. Light particles (called “photons”) scattered off the electrons and created a kind of radiation “fog” which still permeates the universe. As the universe expanded, the plasma fog grew cooler. When the universe cooled down, protons and electrons combined to form neutral hydrogen atoms.

The dense “plasma fog” of the earlier superhot era became transparent, leaving a microwave “signature” that could conceivably be detected. Physicists called this the Cosmic Microwave Background Radiation or CMBR.

If the CMBR could be detected, it would be convincing evidence that the Big Bang had actually occurred. On May 20, 1964, two Bell Telephone laboratories radio astronomers Robert Wilson and Arno Penzias, discovered the CMRB and were awarded the Nobel Prize.

Religion and the Big Bang

There is absolutely no evidence of what happened before the Big Bang. Yet it remains a uniquely alluring question. Over the centuries virtually all religions have put forth their explanation of how the universe began. And a creation hypothesis is a cornerstone of every religion.

The Old Testament, the Jewish Bible, begins with these words:

In the beginning God created the heaven and the earth. And the earth was without form, and void; and darkness was upon the face of the deep. And the Spirit of God moved upon the face of the waters. And God said, let there be light: and there was light.

The Hindu Puranas, ancient religious texts, put forth the idea of an eternal universe, with no beginning or end. But this universe is cyclic. The Katha Upshanid states that after the primary creation, there are periodic annihilations of the present universe. Although eternal, the universe goes through several “Big Bangs” and “Big Crunches.” These include the original creation of the universe then secondary re-creations, after its periodic dissolutions.

The Rig Veda, the oldest of the sacred books of Hinduism, which appeared around 1500 BCE, claims that the world began from a point through the power of heat. Many prominent physicists, including Niels Bohr, Irwin Schrodinger, Robert Oppenheimer and Werner Heisenberg, believed that the Rig Veda described a cyclical model for the universe, complete with big bangs and big crunches.

The Rig Veda posits a creation that seems to be consistent with a big Bang model:

Then was not non-existent in or existence: there was no realm of air, no sky behind it. What covered in, and where? And what gave shelter?… Death was not their aught immortal. No sign was there, the days and nights divider. That One Thing, breathless, breathed by its own nature, apart from it was nothing whatsoever.

Catholicism and the Big Bang.

At the Pontifical Academy of Sciences 1951 meeting, the Pope declared that the big bang theory is consistent with the Catholic concept of creation. Conservative groups in the religion treat the Big Bang as an historical interpretation of the doctrine of creation.

Competing Scientific Speculations

Sean Carroll, a Cal Tech astrophysicist, theorizes that the Big Bang was a point connecting us to a copy of our universe, with this difference: in our universe time runs forward, and in the mirror-image universe he hypothesizes, time runs backwards. The two universes joined at the moment of the Big Bang. Carroll also suggested that our universe may just be a small piece of spacetime that was ripped off a much larger parent universe. That parent universe could have spawned a large number of baby universes, including ours.

The astrophysicist Stephen Hawking points out that just as the Earth has no beginning and ending point because it is a closed sphere, time and space also have no beginning and ending points. Hawking called this the “no boundary problem.” When asked what came before the Big Bang, he quipped: “That’s like asking ‘What is north of the North Pole? It’s logically absurd.’”

Scientists are also exploring the possibility that the Big Bang didn’t begin time. Instead, it was a moment in time in the universe stopped contracting and started expanding. This “Big Bounce” model suggests the possibility of infinite numbers of Big Bangs.

Will We Ever Discover How the Big Bang Occurred?

The collective intelligence that we call “science” has proven to be more powerful than we imagined. The human race, which arose in an instant of time, has used the scientific method to figure out so much about the universe. Yet why and how it started remains a mystery.

Perhaps Isaac Asimov’s The Last Question has already given us the answer: Let there be light.