Why do Indian women apply vermilion on the forehead and on their head at the partition ot the hair after marriage?

   
                         Why do Indian women apply vermilion on the forehead and on their head at the partition of hair after marrige ?

          It is pointed out in the Puranas that no ritual like worship of the deity, sacrifice  or others can be performed without this. Vermilion is considered to be very auspicious by Indians and thus used for various purposes on special occasions like wedding and festivals.
Vermilion is not just used by womenfolk of India. Even men, boys , girls and little children apply a dot of this powder kept in the temples in India when they visit a temple or attend  some religious function. However, for married Indian woman, it is almost compulsory to apply kumkum ( vermilion)  on the forehead and in the parting of their hair every day. Vermilion is applied with index finger or ring finger. It is applied in between the eye brows.
Traditional authentic kumkum or vermilion of India is made by grinding the dried turmeric to a powder. A few drops of lime are added to this yellow powder, which changes its hue to a bright red. Turmeric is the best source of cleansing of skin and the Ayurveda recognizes its therapeutic utility. Hence this red color purifies skin,and a natural binder of all mental faculties.
The spot between the eyebrows is called ' Agya chakra' and is very significant in the spiritual field. It is the centre of all the activities of the body. The sage Yajnavalkya considers this place of Shiva's eye as sacred. This is also known as the ' Third eye '. Application of vermilion at this spot gives coolness and peace. It helps to maintain the balance of hormones like Serotonin and Beta endorphin which destroys stress. Mind becomes pure and leads to good works. Self-confidence gets boosted up.
Vermilion holds a great degree of significance for especially married women. Applying vermilion by women on the head is an indication that the lady is married. It creates reverence for her in the society. In addition, it adds to her beauty. During the marriage ceremony the groom applies sindoor on the forehead and his bride's hair for the first time. From that day onwards, Indian women apply vermilion on their forehead and the parting of hair at the head for the long life of their husband. It is also one of the sixteen adornments specified for married women.
Liberation while living is considered in Indian life to be the highest experience , a fusion of the individual with the universal. The purpose is to search for the whole truth within, so that one may realize one's inner self, unfolding the basic reality of the universe. The individual consciousness, called Kundalini Shakti exists in latent form, not in every human being but in every atom of the universe. The object is to awaken or arouse the feminine energy Kundalini and cause it to unite with Shiva, the pure consciousness pervading the whole universe. This is done through recitation of mantras and meditation
.The Kundalini or feminine energy is the vast potential of psychic energy, the body's most powerful thermal current. Even music and dance can arouse the Kundalini's dormant force and direct it to higher planes, until its perfect unfolding and our conscious awareness of its presence within us is realized. In fact any fine art, if practiced with dedication and enjoyed properly, the joy arising  from that is considered akin to Bliss from realization of the Supreme. This Kundalini lies at the of the spine. When she is aroused, she ascends above to the crown of the head to unite with Shiva, the pure consciousness, whose manifest energy she is, through the psychic centers, the chakras that lie along the axis of the spine as conscious potentials. All the chakras are repositories of psychic energy and they govern the whole condition of being. The chakras are supposed to be six starting from the base of the spine as Muladhara, Svadhishthana, Manipura, Anahata, Vishuddha, Ajna ( between the eye brows ). Sahasrara, the seventh, the transcendent chakra, is situated four fingers' breadth above
the top of the head.
The Sahasrara chakra is said to be the region of Shiva, the Pure Consciousness, while Muladhara is the seat of Shakti, whose form here is Kundalini. Through meditation and certain prescribed discipline the Kundalini Shakti rises through the psychic centers until it reaches its full flowering that is fusion with the Absolute in Sahasrara as Kulakundalini generating Bliss Comsciousness ( ananda )
from the union of Shiva Shakti

The two spots connected with the vermilion are Ajna chakra and Sahasrara.
Ajna chakra - Two currents of psychic energy flow through Ida and Pingala from the base of the Spine, spiralling in opposite directions around the Sushumna meet the Sushumna channel in the region of Ajna chakra ( between the eye brows ). This is called third eye. It controls the various states of concentration realized through meditation and commands one's whole personality . This chakra is associated with various cognitive faculties of the mind. Both mental images and abstract ideas are experienced at this level.Its deity is Paramashiva, as in the Sahasrara, he is represented in this chakra in the form of a bindu ( dot ), symbolizing the inseparable Shiva-Shakti, the cosmic unity whose self-luminous consciousness is all pervading, all -unifying.
Sahasrara meaning ' thousand ' is ' The Lotus of the thousand petals ' located four finger breadths above the crown of the head. Also called Brahmarandhra, it is the meeting place of Kundalini Shakti and Shiva.
It is the center of quintessential consciousness where integration of all polarities is experienced and the Bliss is experienced and this is represented in the form of a bindu. Here the Kundalini merges with Shiva in the midst of eternal Bliss and nectar.
In Ajna chakra, there is still the experience of a self apparently different from the Supreme but in Sahasrara, it is not different. There is no object, no God, there is nothing but the Supreme. There is no
Experience because it is one, it is without a second.
According to Indian tradition, marriage is the eternal union of female and male energy. It is apt that the bridegroom applies vermilion on the bride's forehead between the eye brows and on the parting of hair on her head during the marriage ceremony. It is symbolic. In women, application of vermilion on the forehead protects her from hypnotism and mesmerism by others as this spot is very sensitive, thus her loyalty to her husband is safeguarded.
The spot on the parting of her hair is the point where Shiva resides. This point is more delicate in women than in men. Vermilion protects her from evil  and skin problems.
Application of sindoor on the forehead and in the partition of hair cools both the spots. The young girl assumes the role of a wife, daughter-in -law, sister- in - law and mother after the marriage. Vermilion not only adds charm to her personality but reminds her and gives her mental coolness to carry out the new responsibilities cheerfully.