sir.how to get the ultimate knowledge i.e brahman is only reality ??
the same you refer as "gyana".is it possible to get it while living in world??i.e without renouncing
Whatever you see around you is Brahman. It is very simple to realize. Right from the grain of sand in your shoes to Andromeda galaxy, everything is Brahman. It is clearly stated in our upanishads - 'Sarve Khalvidam Brahma' (Sarve Khalu Idam Brahmam - All things here Brahman). That is the ultimate reality. I think you mentioned about your science background, so it should be easy for you to understand. Everything that you see is made up of energy, since atoms are energy (E=mc squared). We ourselves are nothing else but Brahman. That is why Chhandogya upanishad said 'Tat twam asi' (that is what you are). Now what is this energy, how does it arises out of 'nothing', how does it disappear again into 'nothing', are things that are not known today. That is why our books said 'Brahman is unknowable'. I do not think to know this and realize this (knowing and realizing are two different things, the second thing is like putting what you know into action) any renouncing is required. With best regards,