[VadeRetro]

That last paragraph:

The only explanation, according to Chaboyer and Krauss, for an accelerating universe is that the energy content of a vacuum is non-zero with a negative pressure, in other words, dark energy. This negative pressure of the vacuum grows in importance as the universe expands and causes the expansion to accelerate.

It has an eerily Barry-Setterfieldian "more energy is periodically pumped into the universe from the vacuum, thus violating conservation of energy" kind of ring. I hate it when the loonies get something to lawyer with.

[forsnax5]

... the energy content of a vacuum is non-zero with a negative pressure ...

This sounds like what most of the crevo threads devolve into...

[PatrickHenry]

... the energy content of a vacuum is non-zero with a negative pressure, in other words, dark energy ...

I donno. More energy is actually more matter/energy, which automatically means more gravity. And if gravity has a minus sign (as it must to cancel out matter/energy and result in a net zero for the universe), then this new dark energy stuff must be generating more gravity, which automatically cancels it out and we'd still have a net energy component of zero for the universe. Makes sense? We need Physicist to come to our aid.

[Williams]

No it's not a looney theory, but if you follow the latest in physics and cosmology, you come to realize they ultimately don't know what the heck they're talking about. For example, as you see in this article, their calculations of the age, density, and expansion rate of the universe don't "add up" and so they are forever looking for dark energy, dark matter, or a "cosmological constant" to make up the difference.

I just finished Stephen Hawkings' "A Brief History Of Time." While he keeps expressing hope that those last pieces of the "big picture" puzzle are just around the corner, you realize the physicists are juggling so many theoretical balls that they are going to crash in a jumble before anyone can pick up the pieces and make sense of it.