Thomas Jech
Thomas J. Jech (Czech: Tomáš Jech, pronounced [ˈtɔmaːʃ ˈjɛx]; born January 29, 1944 in Prague) is a mathematician specializing in set theory who was at Penn State for more than 25 years.
He was educated at Charles University (his adviser was Petr Vopěnka) and is now at the Institute of Mathematics of the Academy of Sciences of the Czech Republic.
Jech's research also includes mathematical logic, algebra, analysis, topology and measure theory.
Jech gave the first published proof of the consistency of the existence of a Suslin line. With Karel Prikry, he introduced the notion of precipitous ideal. He gave several models where AC failed, for example one with ω1measurable. The concept of a Jech–Kunen tree is named after him and Kenneth Kunen.
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