Hello, I have two questions I wish to ask concerning Decoherence and entanglement: 1. I am certainly no expert on quantum mechanics, and while I was reading I stumbled upon the concept of decoherence. I understand the idea, but I have a few questions concerning it: 1. theoretically, if the environment "slows down," similar to entering a state of low energy, can a particle that is entangled still produce interferences? 2. Assuming that a system is always changing in some way, does interference completely cancel out? 3. Do particle interferences arise faster than the speed of light (assuming the entangled system is not dissipative)? I also have a few questions concerning entanglement: 1. Is entanglement permanent within a system? 2. Is everything in the universe entangled? 3. If the above is true, then why are there are so much differences between the states of all systems? 4. How and which properties are usually correlated? 5. Is there "anti-entanglement"? Thanks for all who answer my quick questions.