More details: Found here A radical new theory regarding the origin of the universe suggests that gravitational waves, tiny ripples in spacetime first predicted by Albert Einstein back in 1915, could have given rise to cosmic matter, eventually spawning galaxies, stars and planets.
The theory aims to do away with a range of speculative and adjustable parameters within the standard Big Bang theory . The fact that these parameters can be so freely modified is challenging, as it means that scientists can't tell if a model of the beginning of the universe truly predicts observations of the modern cosmos, or if it has simply been adapted to fit this picture.
"For decades, cosmologists have been working on a model, the 'inflationary paradigm,' that suggests the universe expanded at an incredible rate, explaining everything we observe today," team leader Ra⁘l Jim⁘nez of the University of Barcelona told Space.com. "The new model suggests that natural quantum oscillations of spacetime itself, gravitational waves , were sufficient to trigger the tiny density differences that ultimately gave rise to galaxies, stars, and planets."
"Too much flexibility in science can be problematic because it makes it difficult to determine whether a model is truly predicting something or simply adapting, a posteriori [after the fact], to observed data."
This de Sitter spacetime would have decayed completely when its near-equilibrium state, when quantum effects became so strong that they caused the universe to become a chaotic quantum system.
This all represents their model, depending on a single energy scale that goes on to account for all predictions of cosmic evolution.
"This was almost 'magical,' since the only free parameter of the de Sitter scale is its energy scale, and due to its complexity and nonlinearity, this turns out to be linked to the observed level of fluctuations," Bertacca said.
"It is precisely the elegance and simplicity of the proposed model, and the absence of free parameters, that are key.
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