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"Overwhelming" Evidence For Magnetic Monopoles

Thorfinn.au sends along big physics news: magnetic monopoles have been detected at low temperatures in "Dirac strings" within a single crystal of Dysprosium Titanate. Two papers are being published today in the journal Science and two more on arXiv.org, as yet unpublished, provide further evidence. "Theoretical work had shown that monopoles probably exist, and they have been measured indirectly. But the Science papers are the first direct experiments to record the monopole's effects on the spin-ice material. The papers use neutrons to detect atoms in the crystal aligned into long daisy chains. These daisy chains tie each north and south monopole together. Known as 'Dirac strings,' the chains, as well as the existence of monopoles, were predicted in the 1930s by the British theoretical physicist Paul Dirac. Heat measurements in one paper also support the monopole argument. The two, as yet unpublished, papers on arXiv add to the evidence. The first provides additional observations, and the second uses a new technique to determine the magnetic charge of each monopole to be 4.6x10-13 joules per tesla metre. All together, the evidence for magnetic monopoles 'is now overwhelming,' says Steve Bramwell, a materials scientist at University College London and author on one of the Science papers and one of the arXiv papers."

2 of 256 comments (clear)

  1. Re:a magnetic monopole is like a one-sided coin: by anarchyboy · · Score: 5, Insightful

    Yea like that electric charge nonsense, you can't have a particle with a single electric charge! that'd be crazy whatever it is will allways have another side with the oposite charge!

  2. Re:lo, you have defeated me by anarchyboy · · Score: 5, Insightful

    I know what magnetism is, I also know what a magnetic monopole is, hell I even know what a dirac string is and what a spin glass is. Honestly your argument about coins made no sense at all.

    I was attempting to point out that electric charge also has field lines but that they do not have two sides like a coin, the entire point of the discovery of a magnetic monopole is that it doesn't have two sides in the way that all the other magnetic dipoles we are used to have.