Hello, I am learning very, very basic quantum from the internet, and I have a question about the reason why dineutrons cannot exist. I know that the standard answer is that they aren't bound, but I don't understand why they are not, whereas a proton-electron system is. Here is the context in which this question occurred: http://www.vias.org/physics/bk6_04_04.html Is the strong nuclear attraction insufficient to provide bounds for the wavefunction of the neutrons? Why is this the case, when electrostatic interactions are enough for other wave-particle bounds? Can two similar particles with mass just not bound one another? Why is it that adding a proton makes a bound state possible? As I'm sure everyone can tell by now, I am a bit confused, so please go easy on me :] Thank you very much for your help.