By the equation E = mc2, it is stated that energy and mass are related . We have
seen the conversion of mass to energy in an atomic bomb and yes, energy can be
converted back to mass. Such a process was first observed by C.D Anderson in 1932 where he discovered the creation of an electron-positron pair from the energy of a gamma ray photon.
'The strength and weakness of physicists is that we believe in what we can measure. And if we can't measure it, then we say it probably doesn't exist. And that closes us off to an enormous amount of phenomena that we may not be able to measure because they only happened once. For example, the Big Bang. ... That's one reason why they scoffed at higher dimensions for so many years. Now we realize that there's no alternative... '