I know the answer to this is most likely "No", and that there have been other threads on this topic before. But recently someone explained a technique for superluminal communication using entanglement and watching for wave form collapse to transmit data. I've always know this not to be possible, but I didn't know how to refute what he was describing. Any insight you folks could give on this particular case would be much appreciated. Note: I'm not a physicist, just a computer guy so please go easy on the math/notation. :) Quick summary: Use the act of measuring or not measuring one entangled particle to cause wave form collapse (or not) in the other entangled particle. Proposed technique: Alice wants to send data to Bob. They already have someone in the middle sending them bursts of entangled particles every second. They are also setup with a double-slit experiment so if neither of them observes which slit the electrons go through they should each see an interference pattern. When Alice starts measuring which slit the electrons are going through it causes waveform collapse and both stop seeing an interference pattern. Alice then turns the measurement apparatus on/off to transmit data to Bob superluminally. I'm pretty sure there's something wrong with this approach but not sure what it is. It does rest on the premise that measuring one entangled particle causes a collapse in the other so that they either both see interference or not. Is this correct? If so, what else could be the problem? For reference I've read this paper, which touched on some of the ideas refuting superluminal communication, but didn't specifically talk about using the technique of observation to cause collapse in the other particle: http://www.hep.yorku.ca/menary/courses/phys2040/misc/foundations.pdf I also looked at the non-communication theorem, which didn't seem to apply directly either since it seemed more concerned with changing something about the particle rather than simply wave form collapse. In this case it seems pretty clear that Bob either sees the interference pattern or not. http://en.wikipedia.org/wiki/No-communication_theorem If you have any other references to point me to that would be great. Thanks!