Differential equations with singularities

Click For Summary
SUMMARY

The discussion focuses on solving coupled differential equations with singularities, specifically the equations involving functions f(r) and g(r). The user concludes that an analytical solution is not feasible, even when the coupling parameter a is set to zero, necessitating a numerical approach. They attempted to use MATLAB's bvp4c function but encountered limitations due to the singularities of second kind present in the equations. The user seeks assistance in reformulating the equations for use with MATLAB's ode45 function.

PREREQUISITES
  • Understanding of coupled differential equations
  • Familiarity with MATLAB, specifically the bvp4c and ode45 functions
  • Knowledge of singularities in differential equations
  • Basic numerical methods for solving differential equations
NEXT STEPS
  • Research numerical methods for handling singularities in differential equations
  • Learn how to reformulate equations for MATLAB's ode45 function
  • Explore alternative MATLAB functions for boundary value problems
  • Study the implications of coupling parameters in differential equations
USEFUL FOR

Mathematicians, physicists, and engineers dealing with complex differential equations, particularly those with singularities, as well as advanced MATLAB users seeking numerical solutions.

kosmonautilus
Messages
2
Reaction score
0
I have to solve the following coupled differential equations

d^2f(r)/dr^2+1/r*df(r)/dr+(2-2*f(r)^2-2*a*g(r)^2-l_1^2/r^2)*f(r)=0

d^2g(r)/dr^2+1/r*dg(r)/dr+(2-2*g(r)^2-2*a*f(r)^2-l_2^2/r^2)*g(r)=0,

where a is the coupling. I think that it is not possible to solve it analytically (even in case a==0), so i have to do it numerically. I tried it with matlab, but bvp4c can not solve equations with singularities of second kind. Can somebody help me? (I'm a advanced user of matlab)
 
Physics news on Phys.org
Thank you, but for ode45 I need the 4 equations in the form dydx=... To obtain this, I have to divide by r^2 again and I have the same problem with the singularities
dy(1)=y(2)
r^2*dy(2)= r*y(2)+...
 

Similar threads

  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 3 ·
Replies
3
Views
1K
  • · Replies 19 ·
Replies
19
Views
3K
  • · Replies 3 ·
Replies
3
Views
4K
  • · Replies 2 ·
Replies
2
Views
3K
  • · Replies 3 ·
Replies
3
Views
3K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 1 ·
Replies
1
Views
3K
  • · Replies 3 ·
Replies
3
Views
2K