Recent content by anuradha

Hi all, Anybody pls help me to convert cosmic time to conformal time (numerically)... is there any analytical expression for conformal time, \tau , except d\tau=dt/a(t) ? can we approximate \tau \approx -1/aH ?? pls help... Anuradha

hi all,o:) anybody please give me a physical explanation for the Gauss-Bonnet invariant... What is its significance in cosmology??does it contribute to the late time acceleration of the universe?? is it possible to find the variation of Gauss-bonnet term with respect to any given metric?if...

thank you for your reply. let me make it more clear! see for eg: if the action is S=int{d^4x*(L_d+k*L_d^2)}, where L_d characterises the lagrangian density of the fermionic field and k being some constant(to make correct dimensionality)...by adding L_d^2 , S contains a non-linear term, right...

hi, Do the addition of non-linear terms in action play any significant role in string theory?? if so, what is its significance in string cosmology? --- anuradha