[Advaita-l] Regarding Padmanabhaswamy

[Kalyan]

Dear Sri Aditya

//So I am wondering if this is the original representation of Narayana/Vishnu and that Ranganatha was conceived later by Ramanujacharya.//

Srirangam temple is much older than Ramanuja. It is mentioned in Tamil Sangam literature. 

Mahabharata also talks of Vishnu sleeping in the ocean on a giant serpent (without any mention of Shiva linga). 

Having said that, there is no such thing as the original representation of Vishnu. In some temples the idol is in a standing posture, in some temples the idol is in a sleeping posture, in some temples the idol is in a sitting posture. It varies from temple to temple.

Regards
Kalyan