A visual history of the expanding Universe includes the hot, dense state known as the Big Bang and the growth and formation of structure subsequently. The full suite of data, including the observations of the light elements and the Cosmic Microwave Background, leaves only the Big Bang as a valid explanation for all we see. (NASA / CXC / M. WEISS)

This Is Why There Are No Alternatives To The Big Bang

Not everyone is satisfied with the Big Bang. But every alternative is a disastrous failure.

It’s treated as though it’s an unassailable scientific truth: 13.8 billion years ago, the Universe as we know it emerged from a hot, dense state known as the Big Bang. While there were a number of serious alternatives considered for decades, throughout the 20th century, a scientific consensus emerged more than 50 years ago with the discovery of the Cosmic Microwave Background. Despite many attempts to revive a variety of the discredited ideas, as well as attempts to formulate new possibilities, all have fallen away under the burden of the full suite of astronomical data. The Big Bang reigns supreme as the only valid theory of our cosmic origins.

Here’s how we discovered our Universe started with a bang.

The expanding Universe, full of galaxies and the complex structure we observe today, arose from a smaller, hotter, denser, more uniform state. It took thousands of scientists working for hundreds of years for us to arrive at this picture, and yet the lack of viable alternatives isn’t a flaw, but a feature of how successful the Big Bang truly is. (C. FAUCHER-GIGUÈRE, A. LIDZ, AND L. HERNQUIST, SCIENCE 319, 5859 (47))

A suite of new discoveries in the early 20th century revolutionized our view of the Universe. In 1923, Edwin Hubble measured individual stars in spiral nebulae, measuring their variable periods and their observed brightness. Thanks to the work of Henrietta Leavitt in formulating…