gzhpcu

2009-Feb-27, 08:37 PM

From the point of view of cosmology, the vacuum appears to have an energy density, which is sometimes called “dark energy” or the “cosmological constant”, responsible for the observed accelerated expansion of the universe. It is estimated to be 10-29 grams per cc (1 proton per cubic foot).

Ordinary matter slows down the expansion, whereas vacuum energy speeds it up.

In the Standard Model of particle physics, all particles are massless, unless they interact with a special field, called the Higgs field. All elementary particles travel at the speed of light. Those with mass, however, are slowed down by the Higgs field which permeates the vacuum. Higgs field is a vacuum field with no source. The Higgs mechanism fills all of space with a field. Unlike the gravitational field, which is strong around the Sun and the centre of the galaxy, the Higgs field would have essentially the same value everywhere. It is estimated that the energy of the Higgs field results in a trillion tons per cubic center. Using that figure in GR, the universe should expand in less than a nanosecond to a billion times its current size

Ugly solution: Quantum Field Theory needs to find another field with negative energy (this is allowed by QFT) to cancel out most of the energy of the Higgs field, leaving exactly 10-29 grams per cc.

Apparently, nobody has a clue as to what this mysterious field is. (Always assuming that a Higgs field really exists. Hopefully, the Large Hadron Collider will be able to resolve the question...)

Ordinary matter slows down the expansion, whereas vacuum energy speeds it up.

In the Standard Model of particle physics, all particles are massless, unless they interact with a special field, called the Higgs field. All elementary particles travel at the speed of light. Those with mass, however, are slowed down by the Higgs field which permeates the vacuum. Higgs field is a vacuum field with no source. The Higgs mechanism fills all of space with a field. Unlike the gravitational field, which is strong around the Sun and the centre of the galaxy, the Higgs field would have essentially the same value everywhere. It is estimated that the energy of the Higgs field results in a trillion tons per cubic center. Using that figure in GR, the universe should expand in less than a nanosecond to a billion times its current size

Ugly solution: Quantum Field Theory needs to find another field with negative energy (this is allowed by QFT) to cancel out most of the energy of the Higgs field, leaving exactly 10-29 grams per cc.

Apparently, nobody has a clue as to what this mysterious field is. (Always assuming that a Higgs field really exists. Hopefully, the Large Hadron Collider will be able to resolve the question...)