New studies raise questions on fundamental theories about the universe

“At some point, you have to start saying the universe has another wrinkle in it, in the cosmological model [that] could also potentially explain this,” Riess said.

NGC 4394, a barred spiral galaxy situated about 55 million light-years from Earth (photo credit: NASA)
NGC 4394, a barred spiral galaxy situated about 55 million light-years from Earth
(photo credit: NASA)
Multiple new studies about the universe may indicate that our current framework for explaining how the universe works needs some serious adjusting, according to Scientific American.
In one recent series of studies, the first-ever galaxies void of dark matter were discovered, a phenomena which should be impossible according to the currently accepted theory of dark matter which posits that this hypothetical substance is everywhere.
Another issue arose when experiments found discrepancies with the current accepted framework of how the universe expands, which states that the universe expands at a constant rate known as the Hubble constant (Ho).
In recent years, studies found that the universe is expanding more quickly than it was when it was checked by the European Space Agency’s Planck satellite, between 2009 and 2013.
A recent study conducted by Nobel laureate Adam Riess with the Hubble telescope, reduced the uncertainty concerning the faster rate of expansion to just 1.3%, meaning that the different measurements are most likely not a fluke, according to Scientific American. This means that the expansion of the universe may not occur at a constant rate.
"This is not just two experiments disagreeing," Riess explained in a NASA press release. "We are measuring something fundamentally different.
"One is a measurement of how fast the universe is expanding today, as we see it. The other is a prediction based on the physics of the early universe and on measurements of how fast it ought to be expanding.
If these values don't agree, there becomes a very strong likelihood that we're missing something in the cosmological model that connects the two eras."
Riess' findings could indicate that the physics of the early universe was different or that the standard model currently used by physicists needs to be adjusted.
“At some point, you have to start saying the universe has another wrinkle in it, in the cosmological model—in the composition of the universe or in some feature of dark matter or dark energy—[that] could also potentially explain this,” Riess said. “You have to give that some serious consideration.”
These discrepancies, while opening thrilling paths for new research, may also upset our fundamental understanding of the universe based on the accepted frameworks in modern day physics.
Most observations of the universe occur experimentally and indirectly and provide results through theoretical predictions and parameters based around the currently accepted model, Bjørn Ekeberg, a philosopher of science and author of Metaphysical Experiments, explained in Scientific American. Any observation is done within the framework, limiting where and what is observed.
Modern day physics started out with Newton's principles, which worked well for our solar system, but didn't work for much outside of it. Einstein's theories helped create a better model for more of the universe, and the big bang paradigm pretty much stretched the model to the entire universe.
The big bang theory came into play as Edwin Hubble's observation that the universe is expanding created issues with an assumption in the theory of general relativity, which stated that the universe is static in both space and time. Physicists attempted to change this central assumption of the model to say instead that the universe is the same in all spatial directions but variant in time. Big bang theory discusses a possible hypothetical premise for resolving issues with general relativity, not the big bang itself.
Multiple theories and additions have been added to the big bang theory since then. To explain galaxies, which didn't conform to general relativity, dark matter was posited as a possible solution. When supernova measurements of accelerating galaxies didn't fit with the framework, a new theory of dark energy was posited to fix the discrepancy.
"For lack of a clear alternative, it is in a sense stuck with the paradigm," Ekeberg wrote. "It seems more pragmatic to add new theoretical floors than to rethink the fundamentals."
"Contrary to the scientific ideal of getting progressively closer to the truth, it looks rather like cosmology, to borrow a term from technology studies, has become path-dependent: over-determined by the implications of its past inventions," Ekeberg stated.