If matter and antimatter are gravitationally repulsive, then it would mean that the virtual particle-antiparticle pairs that exist for a limited time in the quantum vacuum are "gravitational dipoles." That is, each pair forms a system in which the virtual particle has a positive gravitational charge, while the virtual antiparticle has a negative gravitational charge. In this scenario, the quantum vacuum contains many virtual gravitational dipoles, taking the form of a dipolar fluid.
"We can consider our universe as a union of two mutually interacting entities," Hajdukovic said. "The first entity is our `normal' matter (hence we do not assume the existence of dark matter and dark energy), immersed in the second entity, the quantum vacuum, considered as a sea of different kinds of virtual dipoles, including gravitational dipoles."
He goes on to explain that the virtual gravitational dipoles in the quantum vacuum can be gravitationally polarized by the baryonic matter in nearby massive stars and galaxies. When the virtual dipoles align, they produce an additional gravitational field that can combine with the gravitational field produced by stars and galaxies. As such, the gravitationally polarized quantum vacuum could produce the same "speeding up" effect on the rotational curves of galaxies as either hypothetical dark matter or a modified law of gravity.
PayPal-founder Peter Thiel was so inspired by Atlas Shrugged - Ayn Rand's novel about free-market capitalism - that he's trying to make its title a reality.
The Silicon Valley billionaire has funnelled $1.25 million to the Seasteading Institute, an organization that aspires to launch a floating colony into international waters, freeing them and like-minded thinkers to live by Libertarian ideals.
The floating sovereign nations that Thiel imagines would be built on oil-rig-like platforms anchored in areas free of regulation, laws, and moral conventions.
Mr Thiel and his colleagues say their ocean state would have no welfare, looser building codes, no minimum wage, and few restrictions on weapons.
Thiel meanwhile once a crowd at the Seasteading Institute Conference in 2009 that: 'there are quite a lot of people who think it's not possible.
That's a good thing. We don't need to really worry about those people very much, because since they don't think it's possible they won't take us very seriously. And they will not actually try to stop us until it's too late.'
I've changed the embedded Youtube videos to use IFRAME instead of OBJECT, with the side-effect that they are now directly playable on iPhones and iPads (the video will play in Safari rather than tossing you over to the Youtube app).
But... I think the page loads slower now. I'm not sure, though. It's hard to tell, and I don't know how to meter it. Do browsers lose their minds if there are a lot of small iframes?
The page has 19 Facebook "Like" iframes, 19 "Google+" frames, 16 Youtube iframes, and 63 images for the various flyer and gallery thumbnails. That doesn't seem like it should count as "a lot" in this modern world, but maybe it does?