For three decades, scientists have been puzzled by “dark energy”, a mysterious force driving the accelerating expansion of the universe. Despite its significance in cosmology, dark energy remains an enigma, with no direct evidence to support its existence.
The concept of dark energy was born from observations of nearby supernovae and ancient galaxies. The observation that these distant galaxies are receding from us faster than those closer to us won a Nobel prize. However, the lack of a satisfactory explanation for this phenomenon has persisted.
A new theory, dubbed “Timescape”, offers an alternative explanation for dark energy. According to the Timescape idea, our understanding of the universe’s expansion is based on a flawed assumption: that the universe behaves isotropically, or uniformly in all directions. The measure of this expansion, known as the Hubble Constant, yields two different values depending on how it’s measured.
The James Webb Space Telescope was expected to resolve this tension, but instead, it has exacerbated the issue. The Timescape idea argues that our observation of an expanding universe is actually an illusion created by gravity in certain regions, rather than a genuine expansion.
This concept challenges the traditional understanding of cosmology, suggesting that clocks run slower in areas with enhanced gravity and appear to be expanding faster in voids. Recent data may support this alternative explanation, potentially rendering dark energy unnecessary.
The legacy of Albert Einstein’s work also comes into play here. His theory of General Relativity introduced the “Cosmological Constant”, which was later revived as a possible explanation for dark energy. If the Timescape theory is correct, it would replace the Cosmological Constant with Einstein’s own General Relativity, raising questions about whether the answer was always there.
Source: https://www.dailykos.com/stories/2024/12/27/2293949/-14-Billion-Years-of-Lies-is-Dark-Energy-about-to-be-Solved