Hi, i'm stuck on my homework.. and this particle physics and cosmology chapter is killing me :yuck: a question asks me to discuss the following conservation laws: energy, linear momentum, angular momentum, electric charge (ok so far) AND bayron number, lepton number and strangeness. are all of these laws based on fundamental properties of nature? Explain. Now i do get the laws of conservation of bayron, lepton and strangeness... but what do they mean exactly by fundamental properties? Thanks.