Big Bang Theory

Big Bang theory is the leading explanation for how our universe began. According to the theory, the entire universe began as a tiny singularity that went through an explosive expansion 13.8 billion years ago, gradually expanding into the cosmos we see today. Today, astronomers can detect an "echo" from the Big Bang in the cosmic microwave background, a phenomenon that can be detected with radio telescopes. Big Bang Theory is also the name of a popular CBS sitcom about scientists, where several real-life scientists and astronauts have appeared.

Related Topics: Black Holes, Dark Matter, Gravitational Waves, The Theory of Relativity in Space 

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The centers of massive galaxy clusters are super hot (red), while bright structures show diffuse gas from the intergalactic medium shock heating at the boundary between cosmic voids and filaments. 

Physicists Just Created the Most Detailed Simulation of the Universe in History

By Tim Childers published

An international team of scientists has created the most detailed large-scale model of the universe to date, a simulation they call TNG50.

Early data from the Planck collaboration maps the cosmic microwave background across the sky.

The Universe Might Be a Giant Loop

By Rafi Letzter published

Is the universe flat? Maybe not.

This image of the Type 1a supernova remnant 0509-67.5 was made using data from NASA’s Hubble Space Telescope and Chandra X-ray Observatory. Analyses of Type 1a supernovae has led astronomers to conclude that the universe’s expansion is accelerating, driven by a mysterious force called dark energy.

The Cosmological Conundrum of the Expansion Rate of the Universe

By Paul Sutter published

Different measurements of the universe's expansion yield different results. Are we getting something wrong, or do we need brand-new physics to figure it out?

Cosmic-string loops wiggle and oscillate, producing gravitational waves, then slowly shrink as they lose energy until they disappear.

The Mysterious Cosmic Strings

By Paul Sutter published

These weird defects in space-time should be out there, somewhere.

Researchers have found signatures of strontium in the aftermath of a neutron star merger.

We May Finally Know How the Universe's Heavy Elements Formed

By Charles Q. Choi published

For the first time, scientists have detected a newly born heavy element in space, forged in the aftermath of a collision between a pair of dead stars known as neutron stars.

NASA, ESA, and the Hubble Heritage Team (STScI/AURA)-Hubble/Europe Collaboration; Acknowledgment: H. Bond (STScI and Pennsylvania State University)

How the Universe Stopped Making Sense

By Rafi Letzter published

What's going on?

An artist's illustration of the cosmology and exoplanet research honored by the 2019 Nobel Prize in physics, directed toward understanding our place in the universe.

This Year's Nobel Prize in Physics Mixes 2 Research Fields — And Politics

By Meghan Bartels published

The Nobel Prize in physics this year has gone to two very different research threads — and danced around some big societal issues, even as they celebrate distinguished work.

An artist's depiction of the history of the universe.

Nobel Prize in Physics Honors Scientists Who Transformed Our Ideas About the Cosmos

By Jeanna Bryner published

The Nobel Prize in physics has been awarded to three scientists for unraveling the structure and history of the universe and for changing our perspective of Earth’s place in it.

In this Hubble Space Telescope view of the distant quasar RXJ1131-1231, a foreground galaxy smears the image of the background quasar into a bright arc (left) and creates a total of four images — a phenomenon known as gravitational lensing.

Einstein's Gravitational Lenses Could Clear Up Roiling Debate on Expanding Cosmos

By Charles Q. Choi published

Warps in the fabric of space-time can act like magnifying glasses, and that may help solve a cosmic mystery about the rate of the universe's expansion, a new study found.

An image of the Large Magellanic Cloud taken with a ground-based telescope. The inset image was captured by the Hubble Space Telescope, and shows a galaxy cluster teeming with variable Cepheids, a class of stars that flicker regularly. Using this pulsation rate, scientists have calculated the universe's expansion rate, but that number doesn't match with values derived from other cosmic phenomena, such as the echo of the Big Bang known as the cosmic microwave background radiation.

One Number Shows Something Is Fundamentally Wrong with Our Conception of the Universe

By Adam Mann published

Here's what's going on with the discrepancies in cosmic expansion measurements.

During the brief "inflation" period, the newborn universe expanded far faster than the speed of light, growing from a subatomic size to a golf-ball size almost instantaneously.

The Problems with the Cosmic Calendar

By Paul Sutter published

Our lives here on Earth are small and insignificant and inconsequential — but only in a certain frame of reference, and that frame of reference doesn't necessarily apply to cosmic scales.

A look at our expanding universe from the Hubble Space Telescope's Ultra Deep Field.

New Hubble Constant Measurement Stokes Mystery of Universe's Expansion

By Passant Rabie published

Using red giant stars, scientists calculate new universe expansion rate.

Researchers recently found stardust embedded in a meteorite from Antarctica. This tiny grain made up of carbon-rich material (red) and oxygen-rich material (blue) likely formed in a nova explosion.

This Antarctic Meteorite Holds a Tiny Speck of Stardust That's Older Than the Solar System

By Yasemin Saplakoglu published

This speck of primeval stardust may hold clues about the origin of the solar system.

This is a ground-based telescope’s view of the Large Magellanic Cloud, a satellite galaxy of our Milky Way. The inset image, taken by the Hubble Space Telescope, reveals one of many star clusters scattered throughout the dwarf galaxy.

The Universe Is Expanding So Fast We Might Need New Physics to Explain It

By Mike Wall published

The universe is expanding faster than expected, suggesting that astronomers may have to incorporate some new physics into their theories of how the cosmos works.

Particles acting as "standard clocks" would show different patterns of signals based on what happened in the primordial universe (top: Big Bounce; bottom: inflation).

Massive Clock-Like Particles Could Reveal What Happened Before the Big Bang

By Charles Q. Choi published

To see if there was a universe before the Big Bang and understand how the cosmos evolved after it began, researchers suggest looking for the influence of particles that acted like clocks.

An artist's depiction of the SPHEREx mission at work.

NASA Will Launch a New Space Telescope in 2023 to Investigate the Universe

By Meghan Bartels published

Come 2023, NASA will have a new eye tracking the heavens and looking to solve some of the greatest scientific mysteries we know of.

Cosmic vibrations

'Vibrating Universe' Shares Astronomy with Deaf Students

By Meghan Bartels published

What does a star feel like? A team of scientists put astronomy on a vibrating sound stage in order to tackle such questions.

NGC 6752

Hubble Telescope Discovers 'Living Fossil' Galaxy in Our Milky Way's Backyard

By Mike Wall published

The Hubble Space Telescope has discovered a dwarf galaxy in our own cosmic backyard, a mere 30 million light-years from the Milky Way.

Quasar art

Dark Energy Gets Weirder: Mysterious Force May Vary Over Time

By Mike Wall published

Dark energy is even more mysterious than astronomers had thought, a new study suggests.

In "The Citation Negation" episode, Amy and Sheldon are devastated after learning from a Russian paper that Super Asymmetry has already been discovered and disproven.

Did 'The Big Bang Theory' Get the Science Right? A Lesson in Supersymmetry and Economy Class

By Don Lincoln published

Is super asymmetry a thing? And do big physicists really travel economy class?