"Leonard Parker discovered in the late 1960s that an expanding or contracting Universe would create particles out of a pure vacuum. In effect, the stretching of space jiggles up some of the virtual particles and turns them into real particles.
Would this be the same mechanism that causes the creation of matter during Inflation, or is this referring to a different mechanism? If I understand it correctly, the Inflationary matter creation mechanism requires the presence of a gravitational field in the "stretched" space, but there is no mention of any type of field in the above quote.
A Rotating Wave Theory of the Electron as a Basic Form of Matter