Unfortunately, Robert Gentry is best known to me as the man who taught me that creationists will deceive and slander in order to make their point.
In 1995, I was living in Knoxville, TN, and I was regularly debating thelogical issues on the religion forum on CompuServe (remember them?). Some evolutionists came on that forum, and I thought I was prepared for them.
The reason I thought I was prepared for them is that I had just watched a series of 1-hour programs, produced by a creation museum but hosted and narrated by Robert Gentry. Just the week before Gentry had "exposed" scientific conspiracy and dishonesty by telling the story of the discovery of Lucy, the Australopithecus afarensis skeleton, 40% complete, discovered in 1974 by Dr. Donald Johansen.
The problem is, Gentry's story wasn't true! The evolutionists were miffed that "Christians" had been trotting out this piece of slander for 10 years, when a simple reading of Dr. Johanson's book on the discovery of Lucy would have proven it wasn't true.
I was horrified. I am a careful researcher. You may not agree with everything on this site, but it is all well-researched. I acknowledge what I do not know, and I give people the benefit of the doubt—a legal requirement, by the way—before I accuse them of dishonesty. In this case, I violated my own standards out of trust for a "Christian" defending the Bible.
It's a mistake that I shall never repeat. I now examine every creationist accusation and claim that I run across. For ten years now I have found that well over 90% of the "stunning" quotes and facts that creationists "expose" are the results of poor and incomplete research or purposeful dishonesty.
That's no exaggeration.
Robert Gentry just happened to be the one to introduce me to the rampant dishonesty in creationism. He's certainly not unique in that respect.
He is, however, unique in this respect …
Robert Gentry is known for one particular study, on polonium halos. Polonium is a radioctive element that becomes lead as it decays.
Basically, here's what's happened. Gentry found some granite with polonium halos in it. Those look like the picture to the right. These halos are caused by polonium-218 breaking down through a series of steps into lead-206.
For all radioactive materials, we can determine how fast it decays. The speed is measured in half-lives. A half-life is the amount of time that it takes for half of the radiocative material to decay. For Polonium-218, that time is just over 3 minutes.
Gentry argues that this means that the granite went from a molten state to a solid state in less than the time it took all of the Polonium-218 to decay. Since half of it was decaying every 3 minutes, basically all of it would have decayed within half an hour. This is much shorter (to say the least) than the millions of years that science says the granite needed to cool.
There's a more thorough and simple to understand explanation at this creationist site. I also got the polonium halo picture from that site.
This is a problem to established theory on the age of the earth, and it's all the more problematic since Gentry was able to get his work published in the prestigious journal Science, not just once but twice, in 1968 and 1974.
Refutations of Gentry's work have been published. Gentry complains—rightly, it seems to me—that these refutations have not been published in Science, like his was; however, J. Richard Wakefield did publish his refutation in the Journal of Geological Education, also a peer-reviewed journal.
The arguments back and forth are complicated. Not being a geophysicist, I'm not qualified to pass judgment on this argument. For the moment, though, I have to give the upper hand to Robert Gentry for now. Until someone refutes his study in Science or Nature, he has a right to say he's not been answered in 35 years.
Does that make Robert Gentry the holder of the only young earth argument that has strong legs? In my eyes it does.
In the end, though, "extraordinary claims require extraordinary evidence." A very ancient age for the earth is supported by massive amounts of data, including some of the same data Robert Gentry uses! Radioactivity and the half-life of radioactive elements are at the heart of dating methods. Natural structures like the Haymond formation show an advanced age for the earth and make it impossible that the flood created the layers of the earth, as all anti-evolutionists assert. Finally, Gentry's polonium halos don't answer the question of the lineage of humans, the lineage of whales, or any of the other fossils establishing that life evolved over time.
It seems much more likely that there's a mistake in Robert Gentry's interpretation of his halos than that all these other evidences, especially physical ones like the Haymond formation, are being misinterpreted. Especially since an alternative interpretation of Gentry's halos was published in a peer-reviewed journal.
Dr. Robert Gentry is a nuclear physicist who has worked at the Oak Ridge National Laboratory (where the atomic bomb was discovered). He received a masters degree in physics from the University of Florida, and he's been awarded an honorary doctorate from Columbia Union College, a 7th Day Adventist university.
Dr. Gentry has been a 7th Day Adventist since 1959. He has laid low on his creationist position when publishing for Science and Nature, but has otherwise been an outspoken advocate of young earth ideas. He is currently in a legal battle with Los Alamos National Laboratory due to their refusing to accept papers on astronomy that he tried to post to their public message board.