Scientists who research the cosmos have a favourite philosophy known as the “mediocrity principle,” which argues that Earth, the sun, and the Milky Way galaxy aren’t particularly unique in comparison to the rest of the universe.
New research from CU Boulder also adds another evidence to the case for mediocrity by demonstrating that galaxies are, on average, at rest in relation to the early cosmos. This new cosmological result was recently published in The Astrophysical Journal Letters by Jeremy Darling, an astrophysics professor at CU Boulder.
“What this research shows us is that we have a strange motion, but that strange motion is consistent with everything we know about the universe, nothing unusual going on here,” Darling explained. “Neither as a galaxy nor as observers, we are unique.”
What Did The Researcher Found?
Researchers found the cosmic microwave background about 35 years ago, which is electromagnetic radiation left behind from the Big Bang’s origin. The cosmic microwave background seems warmer in our direction of motion and cooler in the opposite direction.
Scientists can deduce that the sun and the Earth circling it, is travelling in a specific direction and at a specific pace based on the glow of the early universe. Our inferred velocity is a fraction of a percent of the speed of light, which is minuscule but not zero, according to researchers.
How Can Scientists Verify This Inference?
Scientists can independently verify this inference by counting or adding the brightness of galaxies visible from Earth. They can do so because of Albert Einstein’s special relativity theory, published in 1905, which explains how speed affects time and space.
What Does The Theory Of Relativity States?
A person on Earth looking out into the universe in one direction, the same direction that the sun and the Earth are moving, should observe brighter, bluer, and more concentrated galaxies in this application. Similarly, looking in the opposite direction should reveal galaxies that are darker, redder, and farther apart.
What Happened When The Scientists Tried To Count The Galaxies?
However, when scientists attempted to count galaxies in recent years, a challenging task they came up with figures that imply the sun is travelling faster than originally thought, contradicting orthodox cosmology.
“Counting galaxies throughout the entire sky is difficult—you’re usually restricted to a hemisphere or less,” Darling added, “Then there’s the matter of our own galaxy interfering. As you approach our galaxy, it includes dust, which allows you to see fewer galaxies and makes them appear dimmer.”
Darling was intrigued and confused by this cosmological puzzle, so he started to dig deeper into it.
He was also aware of two new surveys, the Very Large Array Sky Survey (VLASS) in New Mexico and the Rapid Australian Square Kilometer Array Pathfinder Continuum Survey (RACS) in Australia, both of which could aid in galaxy counting accuracy and give light on the velocity conundrum.
Darling discovered that the number of galaxies and their brightness were in perfect agreement with the velocity astronomers had previously predicted from the cosmic microwave background when he evaluated the surveys.
He explained, “We find a bright direction and a faint direction—we find a direction with more galaxies and a direction with fewer galaxies.” “The main distinction is that it has the appropriate speed and aligns with the early cosmos from the cosmic microwave background. Our cosmology is in good shape.”
This is because Darling’s conclusions differ from previous findings, his paper will almost certainly trigger a slew of follow-up investigations to either validate or refuse his findings.
Significance Of These Findings
The findings are a good real-world example of Einstein’s special relativity theory, and they show how academics are still putting the theory into practice, more than 100 years after the great physicist first presented it.
Darling remarked, “I love the concept that this basic principle that Einstein told us about so long ago is something you can see.”
“It’s a strange and esoteric phenomenon, but if you go out and count galaxies, you can see this lovely effect. It’s not as strange or obscure as you would believe.”