Recent content by Dali

This is not only difficult (as pointed out by @russ_watters), but impossible. Noice cancelling technology relies on a microphone to continually monitor the incoming noice or signal, so an inverted signal can be created to cancel it. Since your ringing is not a real incoming audio wave, no device...

Hi Hazel! You have already gotten great answers, and seem to start to get a grip on the QM formalism of superpositions! The question "why" anything occurs though is always a tricky slope with no definite answer... If you ask why A is true and someone says it is because of B, you just then...

Yes. I should have been clearer that alt (1) is the interpretation people get into when NOT taking relativity into account. It will always clash with some measurements in reality. That is the (wrong) interpretation that people use when concluding "faster-than-light" in these cases... (Edit...

I think this is a good example of the gist the OP really was asking for. In this case it seems obvious that the crew/persons on the rocket (or whatever vessel this might be!) manages to travel much faster than light as seen from within their own rocket. Depending on whether the crew where aware...

As many pointed out, it is of course a down to a definition of choice. But it is also easy to get an intuitive understanding of why so many systems in nature are well-described by harmonic sinusoidal oscillations - it is simply down to the fact that all oscillations are around some equilibrium...

This is a common, and understandable, confusion most people have when hearing about quantum superpositions. When people hear about Schrödingers cat for example, it is not at all clear why, or if, there is any difference between just not knowing and being "in a superposition". The difference...

I think this in an excellent question, and agree it is kind of hard to answer without going into the full details of a specific quantum algorithm. I will try however to formulate my understanding of what I guess is the key question here - more precisely how does a quantum computer utilize...

You keep missing out on some of the complexity here. There are TWO basic assumptions that go into the derivation of Bell's inequality; hidden variables (Objectivity), and separation of variables in the correlation function, corresponding to the assumption that the measurements are independent...

Actually, you can say more. They are correlated in a specific way that would have been impossible if the two measurements were independent of each other. That is the assumption of separating variables in the derivation of Bell's inequality that is violated here. And not violated for correlated...

That is what I tried to say in simpler words. I agree the wording "affecting the wavefuntion of the other" is too simplified for a two-particle state. But clearly a measurement of one of the particles affects the whole two-state wavefunction (that the other particle is a part of). And the fact...

Before going into the details, let's get the basics right: Not really. Many popular explanations mix up entanglement with plain correlation. It is true that all entangled pairs of particle are correlated, but not the other way around, i.e. all correlated pairs are not entangled. Entanglement is...

Actually, I do remember reading a preprint a long time ago that proposed a test that would do just that. The idea is pretty weird, but maybe interesting from a philosophical point of view... The setup was that you connect a gun to a detector in such a way that it has a 50% chance of firing...

whiteboard1 - It's a little different in different setups, there are several EPR/Bell-type setups. A common setup is an entangled pair of spin-half particles in a singlet state. In that case one knows that the sum of the two particles spin is zero. So if one measures the spin of one of the...

I agree. To my knowledge this is the only definition that the scientific community agrees on. Just as space is defined as "what we measure with meter-rods". This is how Einstein defined time and space, and it is precisely this "time" and "space" that relativity says anything about. For...

Superconductivity is a many-body quantum mechanical effect, and can not be understood in terms of semi-classical pictures. The reason a superconductor has zero resistance is because the groundstate of the many-body system of interacting electrons has a finite energy gap to its first possible...