Quantum effects in DNA

This is a monograph on geometrical and topological features of DNA which arise in various quantization procedures also arise in quantum field theory. It is observed that the topological properties of a DNA molecule and formulated bending (curvature) and twisting (torsion) in terms of these gauge fields. A significant result of this formalism is that bending and twisting are not independent entities. The formulation of DNA supercoil in terms of an antiferromagnetic spin chain gives rise to the entanglement entropy which induces the entropic potential associated with the free energy per unit length corresponding to the entropy cost of confining a stiff polymer inside a narrow tube. The entanglement entropy effectively represents the thermodynamic entropy and this repulsive entropic potential opposes the elastically driven collapse of a supercoil which can occur at zero temperature. It is shown that denaturation of a DNA molecule corresponds to zero temperature quantum phase transition induced by a quench when the temperature effect is incorporated in the quench time.