Big Bang confirmed again, this time by the Universe's first atoms (Synopsis)

"In the current cosmological model, only the three lightest elements were created in the first few minutes after the Big Bang; all other elements were produced later in stars." -Fumagalli, O'Meara and Prochaska, 2011

When it was first conceived, the idea of the Big Bang was spectacular for the fact that it made three incredibly distinct predictions, ranging from the largest scales down to the smallest. As we looked from million to billions of light years away, we should find that the Universe expands at a rate that changes depending on what’s in it; there should be a leftover, uniform glow in all directions; and the first atoms, before stars formed, should exist in a very particular abundance.

The abundances of helium, deuterium, helium-3 and lithium-7 are highly dependent on only one parameter, the baryon-to-photon ratio, if the Big Bang theory is correct. Image credit: NASA, WMAP Science Team and Gary Steigman.

These ratios were notoriously difficult to observe, because it required a serendipitous alignment of an ultra-distant light source behind a pristine cloud of gas that never formed stars. And yet, here in the 21st century, we’ve actually found multiple systems that have those exact properties! One can calculate the expected abundances from Big Bang nucleosynthesis, and the measurements are finally getting good enough to compare the results with the predictions. The agreement is beyond spectacular!

An ultra-distant quasar will encounter gas clouds on the light's journey to Earth, allowing us to measure all sorts of parameters, including absorption abundances. Image credit: Ed Janssen, ESO.

The Universe’s first atoms, forged just four minutes into the Universe but observed billions of years later, confirm the Big Bang yet again.

More like this

"We don't understand how a single star forms, yet we want to understand how 10 billion stars form." -Carlos Frenck When we look out into the distant Universe, we're also looking back into the Universe's past. The farther away an object is, the longer it's taken its light to travel from it to our…
"The discovery of deuterium and the marked differences in the physical and chemical properties of hydrogen and deuterium, together with an efficient method for the separation of these isotopes, have opened an interesting field of research in several of the major branches of science." -Harold Urey…
"It took less than an hour to make the atoms, a few hundred million years to make the stars and planets, but five billion years to make man!" -George Gamow Earlier today, a video (from last month) was released where one of the members of the US House of Representative -- a member who sits on the…
"I see a lot of new faces. But, you know the old saying, 'out with the old, in with the nucleus.'" -The Simpsons Looking around the Universe today, there's no doubt that there's plenty of hydrogen and helium around; after all, it's the nuclear fusion of hydrogen into helium that powers the vast…