Big bang artistic concept

The Big Bang is the scientific theory describing the origin of the universe about 13.8 billion years ago from an extremely dense and hot state.

About this subject

The Big Bang was not an explosion in space, but the expansion of spacetime itself. The theory is based on observations of the universe's expansion, discovered by Edwin Hubble in the 1920s, showing that galaxies are moving away from each other. Another crucial piece of evidence is the cosmic microwave background radiation, detected in 1965 by Penzias and Wilson, which is the afterglow of the universe's hot early state.

The term "Big Bang" was coined by Fred Hoyle in 1949 during a radio broadcast, originally as a derogatory name, but it stuck. The standard Big Bang model explains the abundance of light elements like hydrogen and helium, and is complemented by cosmic inflation, a rapid expansion in the first moments.

Artistic depictions of the Big Bang are common in popular culture, often showing a bright explosion. In science, the earliest moments are opaque to light, and computer simulations attempt to recreate conditions of unimaginable temperatures and densities. The study of the Big Bang continues with telescopes like James Webb, which observes distant galaxies to understand the evolution of the cosmos.

Frequently Asked Questions

What is the Big Bang?

It is the scientific theory explaining the origin of the universe from an extremely hot and dense state about 13.8 billion years ago, followed by expansion and cooling.

What are the main pieces of evidence for the Big Bang?

Key evidence includes the expansion of the universe (Hubble's law), the cosmic microwave background radiation, and the primordial abundance of light elements such as hydrogen and helium.

Why is it called the Big Bang?

The name was popularized by astronomer Fred Hoyle, who used it critically during a radio broadcast in 1949. Despite its derogatory intent, the term became standard.