The Arya Samaj is open to all human beings irrespective of caste, religion, creed, nationality, race, gender or sexual orientation unlike the casteist Hindu smritis which have no basis in the Vedas or shrutis and are obsolete manmade structures..
The Arya as per the Dharmic religious philosophies means the noble one or who does noble deeds.
' Arya is not a race; Arya means a noble-minded person. The word Arya is often confused with a race. In the beginning, western historians propounded this theory of the Aryan race. That developed into Hitler's Aryan superiority. And when Hitler died, the Aryan race theory also died ! But the word Arya is used in sanskrit always for the noble-minded person. Take any sanskrit drama. The person will address another character as 'My dear Arya,noble-minded person'. And Buddha spoke of his teachings as Arya-satyani, Noble Truths. Noble is the word for Arya there. The four Noble truths, Arya Satyani. So, the word Arya was used by Buddha, as also by earlier Vedic literature. And this word, Arya is, therefore, a very great word in Sanskrit. Be an Aryan means, be noble-minded. Don't be petty, don't be small. 'Swami Ranganathananda, commentary of the Bhagavad gita ( Volume 1,Chapter 2.88)
You can see that the greatest vedic philosophers like Gaudapada, Adi Shankaracharya, RAmanuja and Madhava emerged from south India which gave the vedic philosophies of Advaita, Vishistadvaita and Dvaita respectively.
Adi Shankacharya consolidated the Advaitan doctrine and established centers of Advaita in north, south, east ,west and central India in the seventh century A.D, defeating all other religious scholars and their philosophical doctrines in debate.