Discussion Overview
The discussion revolves around the amount of dark energy in the observable universe at different times, exploring theoretical formulations and implications based on current understanding in cosmology. Participants examine the relationship between dark energy and the scale factor over time.
Discussion Character
- Exploratory, Technical explanation, Debate/contested
Main Points Raised
- One participant proposes a formula for dark energy as being inversely proportional to the cube of the scale factor, suggesting that dark energy would be about one-fourth of its current amount 6 billion years ago.
- Another participant argues that the total amount of dark energy is not a useful quantity in General Relativity, emphasizing that density is a more relevant measure, which may be constant over time.
- A third participant points out that the radius of the observable universe does not scale directly with the scale factor and corrects the scale factor value mentioned by the first participant, indicating that it should correspond to a past time rather than a future time.
- This participant also estimates that the total vacuum energy in the observable universe would be about one-eighth of today's value if density is assumed constant.
- A later reply acknowledges a misunderstanding regarding the scale factor term, indicating a learning process in the discussion.
Areas of Agreement / Disagreement
Participants express differing views on the usefulness of measuring total dark energy versus density, and there is no consensus on the proposed formula or the implications of scale factor adjustments.
Contextual Notes
There are unresolved assumptions regarding the definitions of energy and density in the context of General Relativity, as well as the implications of scale factor changes over time.