Astrophysicists: “The Big Bang is not the beginning of the universe and we have known it for 40 years”
According to astrophysicists, “…the Big Bang is not the beginning of the universe and scientists have known it for almost 40 years…”
To think that the universe and everything in it were born at the time of the Big Bang is “one of the biggest misconceptions in science” according to an astrophysicist and scientific author.
This is an “attractive and beautiful” image that explains much of what we see, but, “unfortunately”, it is also “incorrect”, and scientists “have known for almost 40 years,” argues in an article for Forbes astrophysicist and scientific writer Ethan Siegel, who calls it “one of the greatest misconceptions of the universe”.
A festive portrait of our Milky Way galaxy shows a mishmash of gas, charged particles and several types of dust. Credits: ESA/NASA/JPL-Caltech
According to Siegel, the original idea suggests that the universe emerged from a hot, dense state, and is now expanding and cooling. If we “continue to extrapolate” into the past, the universe would become “warmer, denser, and more compact” until a time when “density and temperature rise to infinite values, where all matter and energy in the universe are concentrated in a single point: a singularity.
It is understood that this singularity—where the laws of physics “break”—is also “the end point,” which represents the origin of space and time, argues the author of the article.
Nevertheless, he continues, there are some puzzles and paradoxes that the Big Bang theory cannot explain. “The Universe does not have different temperatures in different directions, even though an area billions of light-years away in one area never had time (since the Big Bang) to interact with or exchange information with a region billions of light-years in the opposite direction.”
In 1979, American scientist Alan Guth proposed an alternative to the singularity of the Big Bang: the theory of cosmic inflation, which consisted of an early phase of exponential expansion before the Big Bang, and that could solve all these problems.
If the Big Bang was not the start of the universe, what was?
In this cosmic state, quantum fluctuations would continue to exist, and as space expanded, they would spread across the universe, creating regions with slightly higher or slightly below average energy densities,
Siegel says, adding that when this phase of the universe to its end, that energy “would become matter and radiation, creating the hot and dense state synonymous with the Big Bang.”
To test this idea, one had to measure fluctuations in the surplus glow of the Big Bang and find a particular pattern consistent with inflation predictions. In the 1990s, 2000, and then again in t2010, scientists measured those fluctuations in detail and found exactly that.
“The big Big Bang definitely happened but after the cosmic inflation phase. What happened before inflation – or whether inflation was eternal in the past – is still an open issue, but one thing remains certain: the Big Bang is not the beginning of the universe, “concludes the scientist.