BUILT FOR THE LONG TERM. With a legacy that began in 1860, Guardian has successfully weathered many market cycles. Our clients rely on us to be here when they and their loved ones need us. Our recognition of that requirement has shaped the firm throughout the years, enabling Guardian to prosper and grow.
Radon is a colorless, odorless, radioactive gas. It forms naturally from the decay (breaking down) of radioactive elements, such as uranium, which are found in different amounts in soil and rock throughout the world. Radon gas in the soil and rock can move into the air and into underground water and surface water. Radon is present outdoors and indoors.
Set theory is subdivided into three main areas. Naive set theory is the original set theory developed by mathematicians at the end of the 19th century. Axiomatic set theory is a rigorous axiomatic theory developed in response to the discovery of serious flaws (such as Russell's paradox) in naive set theory.