In Śrīmad-Bhāgavatam there is a great deal of information given about the Vaikuṇṭha planetary systems, which are beyond the material universe. Similarly, a great deal of inconceivable information is given in the Caitanya-caritāmṛta. Any attempt to arrive at this information through experimental knowledge will fail. The knowledge simply has to be accepted. According to the Vedic method, śabda, or transcendental sound, is regarded as evidence. Sound is very important in Vedic understanding, for, if it is pure, it is accepted as authoritative. Even in the material world we accept a great deal of information sent thousands of miles by telephone or radio. In this way we also accept sound as evidence in our daily lives. Although we cannot see the informant, we accept his information as valid on the basis of sound. Sound vibration, then, is very important in the transmission of Vedic knowledge.
The Vedas inform us that beyond this cosmic manifestation there are extensive planets in the spiritual sky. This material manifestation is regarded as only a small portion of the total creation. The material manifestation includes not only this universe but innumerable others as well, but all the material universes combined constitute only one fourth of the total creation. The remaining three fourths is situated in the spiritual sky. In that sky innumerable planets float, and these are called Vaikuṇṭhalokas. In every Vaikuṇṭhaloka, Nārāyaṇa presides with His four expansions: Saṅkarṣaṇa, Pradyumna, Aniruddha and Vāsudeva. This Saṅkarṣaṇa, states Kṛṣṇadāsa Kavirāja in the eighth verse of the Caitanya-caritāmṛta, is Lord Nityānanda.