Research Suggests Dark Energy May Have Changed Sign Billions of Years Ago

New research, based on an alternative gravity theory, proposes that dark energy, the force accelerating the universe's expansion, might have transitioned from negative to positive approximately 9.5 billion years ago. This finding, derived from the sign-switching ΛCDM model, could reshape cosmic history understanding and potentially explain the Hubble tension. However, this remains a theoretical possibility requiring further validation against more precise data.