A concept proposed by scientists in 1998 to explain the accelerated expansion of the universe, dark energy seems like a metaphor for a phenomenon still unknown to science.
In fact, physicists needed to include a new component in their equations to explain the acceleration of the universe, as calculations based on the theory of general relativity did not match what they observed in the cosmos. In this sense, dark energy comes in as a provisional substitute to explain the energy needed to drive all this acceleration.
Recently, a team of physicists and astronomers from the University of Canterbury, in Christchurch, New Zealand, questioned the traditional view of the expansion of the universe. In a published study in Monthly Notices of the Royal Astronomical Society: Lettersthey used spectroscopic data on the changing brightness of supernovae over time.
The new method showed strong evidence that “the Universe is expanding in a more varied and ‘disorganized’ way” according to a press release.
What is dark energy?
Standard model of current cosmology, the so-called Lambda-CDM (English initials for cold dark matter) proposes a universe where dark energy — represented by the Greek letter “Λ” — is responsible for accelerating the expansion of the universe.
In this model, galaxies are connected by a kind of invisible web of dark matter, “made of heavy particles that do not interact with anything”, but whose presence is observed through gravity.
Within this hypothetical scenario, dark energy, which represents almost 70% of the cosmos, is the explanation for the acceleration observed in supernova explosions, which appear further away than they should, if the Universe were not expanding.
Today the current model of the expansion of the universe is being challenged by new evidence, such as the residual glow of the Big Bang (cosmic background radiation), in which the early Universe is at odds with the current expansion.
Furthermore, recent data obtained by the Dark Energy Spectral Instrument (DESI) suggests that the ΛCDM model, which adopts a constant dark energy, does not adapt to new dynamics where it evolves over time.
How does the new Timescape model work?
The evidence uncovered in the current study supports the Timescape model, something like the “temporal landscape” of cosmic expansion in Portuguese. The new proposal does not depend on dark energy, as differences in the stretching of light are not attributed to an acceleration of the universe, but rather the way we calibrate time and distance.
The new model proposes that, according to Einstein’s theory, gravity slows down time. Thus, a perfect theoretical clock in empty space would run faster than it does inside a galaxy. Inside the Milky Way, for example, this clock would be about 35% slower (due to gravity) than in large cosmic voids, the authors say, where billions of years would have passed more quickly relative to Earth.
For the study leader, David Wiltshire, “dark energy is a misidentification of variations in the kinetic energy of expansion, which is not uniform in a Universe as irregular as the one we actually inhabit.” In this sense, says the professor, the research offered solid data and arguments about the way in which the cosmos is expanding and the mysteries involved in this process.
And he promises: “With new data, the greatest mystery in the Universe could be solved by the end of the decade.”
This content was originally published in Dark energy is not pushing the Universe away, because it does not exist, says study on the CNN Brasil website.
Source: CNN Brasil
Charles Grill is a tech-savvy writer with over 3 years of experience in the field. He writes on a variety of technology-related topics and has a strong focus on the latest advancements in the industry. He is connected with several online news websites and is currently contributing to a technology-focused platform.
