4 ms·i guess he has never heard of a stable isotope.by baremetal 5y agoi guess he has never heard of a stable isotope.d_tr 5y agoStable isotopes decay but at much slower rates. Even protons decay.addaon 5y agoWhile neutrons do decay in the standard model (half life on the order of 10 minutes, observed), protons do not decay in the standard model, nor has proton decay ever been observed -- and folks have looked.