How to remove a singularity

*To*: mathgroup at smc.vnet.net*Subject*: [mg130520] How to remove a singularity*From*: William Duhe <williamduhe at hotmail.com>*Date*: Thu, 18 Apr 2013 05:34:35 -0400 (EDT)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com*Delivered-to*: l-mathgroup@wolfram.com*Delivered-to*: mathgroup-newout@smc.vnet.net*Delivered-to*: mathgroup-newsend@smc.vnet.net

Bellow I have a differential equation which hits a singularity at low values of t. What I want to do is somehow utilize the WhenEvent command in order to replace the last factor of the equation (2/t a'[t]) with 0 at low values of t in order to avoid getting errors. Is there a way to do this? Here is an example of the equation and how I attempted to use the Whenevent Command. q = NDSolve[{a''[t] == 1/2 a[t]^2 + 1/6 a[t]^6 - 1/4 a[t]^4 - 2/t a'[t], a[0] == 1, a'[0] == 0, WhenEvent[t < .1, a'[t] -> 0]}, a, {t, 0, 1}]; any help would be appreciated!

**Follow-Ups**:**Re: How to remove a singularity***From:*"Ralph and Dominique Crenshaw" <raldom@verizon.net>