Q&A: Cosmology

Q:
This is a great new discovery of gas in the IGM. Is there going to be a new estimate of the average density of the IGM now? I think it is a lot denser than current theory allows.

A:
The density varies from place to place, but the average seems to be coming out in the predicted range, namely 10 to 100 hydrogen nuclei per cubic meter, with a small percentage of heavier elements mixed in.