Quad magnetism
From Tardis Wiki, the free Doctor Who reference
Quad magnetism was, according to the Fifth Doctor, "the only force known to shield anti-matter." It was created when a Q star burnt out. Omega once took advantage of quad magnetism, hiding behind it in the area of space known as the Arc of Infinity. When the Doctor and Nyssa passed through the area, the TARDIS sensors detected quad magnetism. (TV: Arc of Infinity)
