The difference between the Heat and Diffusion equation ?

[thepioneerm]

the difference between the Heat and Diffusion equation ?!

Please:

What is the difference between the Heat and Diffusion equation ?!

thank you.​

 

[HallsofIvy]

There is no difference. They are just different names, referring to different applications, for the same type of equation: more formally, a parabolic PDE.

 

[thepioneerm]

There is no difference. They are just different names, referring to different applications, for the same type of equation: more formally, a parabolic PDE.

thank you very much

but I mean the difference case of the coefficient k of the second derivative of u with respect to x

If k > 0 ....

If k < 0 .... ​