Ajativada

Ajātivāda is the fundamental philosophical doctrine of the Advaita Vedanta philosopher Gaudapada. According to Gaudapada, the Absolute is not subject to birth, change and death. The Absolute is aja, the unborn eternal. The empirical world of appearances is considered unreal, and not absolutely existent.

Gaudapada's perspective is based on the Mandukya Upanishad, applying the philosophical concept of "ajāta" to the inquiry of Brahman, showing that Brahman wholly transcends the conventional understanding of being and becoming. The concept is also found in Madhyamaka Buddhism, as the theory of nonorigination.

Ajātivāda:

Taken together "ajātivāda" means "the Doctrine of no-origination" or non-creation.

The concept of "ajāta" was borrowed by Gaudapada from Madhyamika Buddhism, which uses the term "anutpāda":

Taken together "anutpāda" means "having no origin", "not coming into existence", "not taking effect", "non-production".

"Ajātivāda" is the fundamental philosophical doctrine of Gaudapada. According to Gaudapada, the Absolute is not subject to birth, change and death. The Absolute is aja, the unborn eternal. The empirical world of appearances is considered Maya (unreal as it is transitory), and not absolutely existent.

Gaudapada borrowed the concept of "ajāta" from Nagajurna's Madhyamaka philosophy. The Buddhist tradition usually uses the term "anutpāda" for the absence of an origin or śūnyatā.

But Gaudapada's perspective is quite different from Nagarjuna. Gaudapada's perspective is based on the Mandukya Upanishad. In the Mandukya Karika, Gaudapada's commentary on the Mandukya Upanishad, Gaudapada sets forth his perspective. According to Gaudapada, Brahman cannot undergo alteration, so the phenomenal world cannot arise independently from Brahman. If the world cannot arise, yet is an empirical fact, than the world has to be an unreal (transitory) appearance of Brahman. And if the phenomenal world is a transitory appearance, then there is no real origination or destruction, only apparent origination or destruction. From the level of ultimate truth (paramārthatā) the phenomenal world is māyā, "illusion", apparently existing but ultimately not real.

...
Wikipedia