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http://en.wikipedia.org/wiki/Robert_V._Gentry
Robert V. Gentry (born 1933) is a nuclear physicist and young Earth creationist, known for his claims that radiohalos provide evidence for a young age of the Earth. He is a member of the Seventh-day Adventist Church.
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Critics of Gentry, including Thomas A. Baillieul (Baillieul 2005) and John Brawley (Brawley 1992), have pointed out that Po-218 is a decay product of radon, which as a gas can be given off by a grain of uranium in one part of the rock and migrate to another part of the rock to form a uraniumless halo. Apparently a large number of radon atoms are caught or absorbed at a particular point. This has not been proved experimentally, but is supported by the fact that Gentry's "polonium halos" are found along microscopic cracks in rocks that also contain uranium halos (Wakefield 1988).
Precej zakomplicirana stvar, vendar glede na to, da je geologi ne podpirajo, BS.