Recent content by jvangael

Thanks All, but the thing I am looking for are problems with solutions. Not for the Schwarz & Schwarz book per se, but just in general for relativity. I have enough theory to read, but there's no substitute for problem solving. So if any of you have pointers to problem+solutions, let me know...

Hi, I am currently trying to learn some relativity. I am using the book by Schwartz & Schwartz to get some idea of Flat Space Time and the mathematics behind it, I hope to move on to general relativity in the future. My question: I am trying to solve some excercises but I have a hard time...

Hi, The answer is no. What you are talking about are hidden variables. Bell showed that no hidden variable theory can explain all quantum phenomena (Bell particularly meant entanglement here). Jurgen

Hi Blip, So when Bob performs a measurement Alice does not gain any information on her state nor can she tell whether Bob made his measurement. TBut, Bob can conclude in which state Alice's qubit will be in when she measures. After Alice and Bob's measurements are performed on their...

I know for example in one of the first experiments performed to test the Bell inequalities, Alain Aspect used a phenomenon which is called Atomic Radiative Cascades to create entangled photons. The basic idea was to excite a certain atom (Calcium?) to an excited state. Most atoms fall back in a...

Thanks sliboy, It will take me a while to go through them but I sure am interested in some of these results. Thanks, Jurgen

Hi Slyboy, Isn't there a possibility that some relation between entanglement measures and Bell inequalities is possible? Look at section 4.3.4 (4.1.8 in old edition) in Chapter 4 of Preskill's notes. A state \alpha |00> + \beta |11> can violate the CHSH equalities. The amount of violation is...

Hi All, I just came across a paragraph in a little book called "Entanglement" by Amir Aczel. In it it said that Wayne Myrvold proved that it is undecidable whether two states are entangled or not. Does anyone have any knowledge or references to his ideas? Thanks, Jurgen

Hi All, Let me explain some things I learned lately on entanglement measures. First of all, there is entanglement for pure states and entanglement for mixed states. A pure state is unentangled if it can be written as a productstate. A mixed state is unentangled if it can be written as a...

Hi, AFAIK there is no one measure of entanglement. There are different measures which apply well in different situations. I found this article "PRL 78, 12, 2275-2279: Quantifying Entanglement" interesting. Here the authors define a sort of scheme which good entanglement measures should obey...

It depends. Are you interested in core Quantum Computing or are you interested in the foundation of physics? The multiverse idea is interesting but has no practical applications in Quantum Computing; it is more a topic in the realm of philosophy and the interpretation of quantum mechanics. If...

Exactly. TO calculate it easily, for each component of the superposition and for every qubit in each component you apply the hadamard transform. Then you get this (rather large) sum. You then just add all the same components together. Jurgen

My Guess: if there is a ring of people in boats in the - water surrounding the island - then you just leave the island on the opposite side of where the ring is. Unless you meanth ofcourse that the ring of people surround the island like the wall does? Jurgen

Deutch problem Hi Marlon, I think you are mistaken here. There is no entanglement involved in detuch's algorithm. The start states for the algorithm are unentangled and the end state is: ((-1)^{f(0)}|0> + (-1)^{f(1)}|1>)(|0>-|1>) So there is no entanglement involved here. Grover and...

I can't go through all the details but try figuring out for yourself what a Hadamard gate does to all the basis states. Than sum up what you need for the state after an oracly query and apply basic linear algebra. I believe Nielsen & Chuang has a really good overview of the Linear Algebra...