To some astronomy enthusiasts the phrase “big bang” seems awfully superfluous. It’s the shortest of shorthands for describing the origin of everything: stars, planets, people and petunias.
Astronomers think all of this came from an extremely hot and dense fireball that sprang out of a microscopic quantum space netherworld 13.7 billion years ago.
The award-winning science writer-producer Timothy Ferris lambasted the term “big bang” years ago: “For all its triumphs the big bang theory labors under an embarrassing handicap — it’s a misleading, ugly and trivializing name. We’re talking here about the origin of the universe, an event that has been viewed by all cultures with the utmost reverence.”
I received a “big bang” of e-mails following last week’s announcement that the Hubble Space Telescope has seen galaxies that existed almost all the way back to the big bang.
Some e-mails derided the big bang as science dogma and new age Pantheism. Other readers tried to grasp the idea of a universe expanding from somewhere into someplace. (Which it doesn’t, the universe creates space as it expands. There is no ‘center’ or ‘edge.’)
Did the universe have a beginning? We’ve only had tantalizing evidence for less than a century, but the idea is not new. It is at the root of many ancient mythologies. In the biblical Genesis God said, “Let there be light.” This sounds awfully allegorical to the description of the big bang. In fact the universe was nothing but an ocean of light for the first 360,000 years of its existence.
Another writer chided astronomers for using a phrase that sounds too official: “When a term is capitalized and used in output from respected researchers, it then appears to have assumed validation,” he wrote.
One of the e-mails I received suggested replacing “big bang” with “the start of the universe’s current expansion.” But science writers would ignore it as much as they would ignore renaming a black hole something like “Schwarzschild radius class IVa.”
Ironically, the term big bang came from astronomer Sir Fred Hoyle who cooked it up as a sound bite in a 1948 radio call-in show. Hoyle hated the then so-called “primeval atom” theory as intellectually repulsive.
His alternative and now discarded theory called “steady state universe” would have violated the laws of thermodynamics. Over an infinite amount of time entropy would make the universe the same temperature everywhere. There could be no life today.
In 1994 Ferris, Hugh Downs of ABC-TV, and Cornell astronomer Carl Sagan judged over 13,000 entries from people in 41 countries who suggested new names for the big bang, in a contest sponsored by Sky and Telescope magazine.
Some entries included: Matter Morphosis, The Bottom Turtle, Super Seed, Hubble Bubble, Let There Be Stuff, Blast from the Past, the Spark in the Dark, Buddha’s Burp, Trip from Zip, Immaculate Inception, Primal Pop, Jurassic Quark, and Time In!
Suffice to say the esteemed judges concluded there was no viable alternative phrase to simply the big bang.
Here is my Cliff Notes version of the observational evidence today that is consistent with the big bang theory. The evidence convincingly points to a universe that was very different long ago. But, it doesn’t prove the big bang really happened:
The Universe is Expanding: We see galaxies receding from us in all directions. This is a cosmological spectral redshift caused by the stretching of space-time and not a true velocity through space. How do we know? Because the expansion shows time dilation as well; farther Type 1a supernovae take proportionally longer to explode.
The Universe is Evolving: Hubble telescope’s ultra-deep exposures trace galaxy evolution over 13 billion years. Galaxies started out as small compact objects and assembled over time into stately spirals and ellipticals.
There is a Cosmic Microwave Background: The universe has a cooling afterglow from a time it was hot and dense. This microwave energy across the heavens exceeds all the radiation from stars and galaxies. Its acoustic ripples have been mapped in detail.
The Elements Were Built Up Over Time: The chemical elements beyond helium are forged in the fusion furnaces of stars and supernovae. Stellar nucleosynthesis can be traced back to early epochs when the young universe was deficient in heavier elements because they hadn’t been cook-up yet.
Detecting minute ripples in space-time, called gravitational waves, might allow us to make measurements as far back as one second after the big bang. The most fundamental problem is that we can’t retrieve information from what if anything preceded the fireball era. Evidence for a “time before the beginning of time” will likely be forever beyond our grasp.