Unfurling an entire life of failed artistic ambitions in the span of a two-hour film, Chaitanya Tamhane’s remarkable sophomore feature “The Disciple” is decidedly leisurely in its approach. Executive produced by Alfonso Cuarón, Tamhane’s film centralizes the world of Hindustani classical music, in which singers perform an improvised raga, modulating their voices depending on the singer’s emotional state. This highly technical musical form, perhaps most famously popularized in America by Ravi Shankar, serves as the backdrop to the ambitious struggles of Sharad Nerulkar (Aditya Modak), a musical protégé who may not be as talented as he believes he is. “The Disciple” distills the all-consuming nature of an artistic calling, while questioning the relationship between innate talent and hard work. Sharad, on the surface, may seem as talented as the other young performers he competes against, but even his monk-like commitment to learning the form may not be enough for a musical genre that is primarily judged based on micro-changes of pitch and intonation.