Aerofoil Section & Sitar Javari

An aerofoil section uses Bernoulli's Principle to generate lift by creating a difference in air pressure between the top & bottom surfaces of the aerofoil due to the curved surface (camber). Newton's third law of motion also acts as a complementary explanation for the lift generation.

The Angle of Attack is the acute angle between the chord line of an aerofoil & the vector representing the incoming airflow. Increasing the angle increases the lift, but beyond 15° to 20°, there will be an aerodynamic stall.

As crucial as the angle of attack mentioned above, is the angle at which the sitar string leaves the bridge. This, known as "Javari", defines the sound produced by the sitar. The front of the bridge is meticulously filed to a rounded shape (in fact, parabolic as defined by the equation X=Y squared), just like the rounded front edge of the aerofoil section adapted for the wings of an aircraft.

As the rounded front of the aerofoil section is important for developing optimum lift for the aircraft, so is the parabolic rounding of the bridge (javari) to an accuracy of a tenth of a milimeter, crucial for the typical sound of the sitar.

Medical & Spiritual Terminology

In Medical terminology, there are three types of drugs:

1.⁠ ⁠Prophylactic, which prevent the occurence of the disease, for example, vaccines.

2.⁠ ⁠Palliative, which alleviate the symptoms, without actually curing the disease. These are usually prescribed for patients with terminal diseases.

3.⁠ ⁠Therapeutic, which can actually cure the disease.

In Hinduism, the world & family life is sometimes viewed as a terrible disease. "Samsara sagare ghore" says Radha Stuti, a devotional text. In early & medieval Christianity also the world was viewed as "A Vale of Tears." In John Bunyan's "The Pilgrim's Progress", Christian flees from "The City of Destruction", a metaphor for worldly life.

However, most have hankering for worldly life but not for the irksome parts of it. The temple runs, religious rituals & pilgrimages are believed to cater to these. These are similar to the palliative drugs which relieve some sufferings but do nothing to cure the underlying worldliness.

For those who have lost the attraction of this world, spiritual practices are recommended to get the grace of God. These are like the therapeutical drugs which actually try to cure the disease of worldliness.

Those who successfully pass the test of non-attachment to sensory objects, can be compared to those who have imbibed prophylactic drug which protects them from ever getting the virus of worldliness. The Hindus attain Mukti (liberation from the cycle of birth & death), the Buddhists "Nibbana" (Nirvana) & the Christians Salvation (The Celestial City in "The Pilgrim's Progress").

Miracles in Christianity & Hinduism

Catholics believe in miracles. In fact one of the criteria for canonisation (declaring a person to be a Saint) is a verifiable miracle. However, C. S. Lewis (Narnia) in his book on miracles, argues that Incarnation of God (as Christ) is the central miracle. As an Anglican, he chooses to be silent on the miracles attributed to later human saints.

Hinduism recognises ten divine incarnations & also accepts miracles are possible for others also. For example, by doing yogic practices, Ashtasiddhis are believed to be obtained. These are:

1. Anima (reducing one's size)
2. ⁠Mahima (increasing one's size)
3. ⁠Garima (becoming heavier)
4. ⁠Laghima (becoming lighter, levitate)
5. ⁠Prapti (materialise objects)
6. ⁠Prakamya (fulfill any desire)
7. ⁠Ishitva (control of nature)
8. ⁠Vasitva (control of others' mind)

Some or all of these powers may also accrue to those performing spiritual practices to attain liberation (Moksha). However, they are advised not to use them, as, in that case, their spiritual journey will be impeded.