アイテム詳細

要旨

The Lorentzian spacetime metric is refined to an area metric which naturally emerges as a generalized geometry in quantum string and gauge theory. Employing the area metric curvature scalar, the Einstein-Hilbert gravitational action is reinterpreted as dynamics for an area metric. The area metric cosmology of the radiation-dominated early universe does not depart from general relativity, enabling successful nucleosynthesis. But intriguingly, without the need for dark energy or fine-tuning, area metric cosmology explains the observed small acceleration of the late universe.