Recent content by natugnaro

I get it now. Thanks for your answers !

I still don't get it, let's say that N=2, then : ((1-pi)+pi)^N = ((1-pi)+pi)^2 =(1-pi)^2+2pi(1-pi)+pi^2=1 and for N=2 general expression becomes : P(Bi=n)= 2!/(ni!(2-ni)!) pi^ni (1-pi)^(2-ni) what sholud I compare here and find out that it sums up to 1 ?

Ok, a different approach then. I'll first try to solve the simplified problem, let's say there is no player C, and the rest of the problem is the same. After a player A has received 10 cards there are 22 cards left. From these 22 cards, 10 go to player B, the rest goes to the Skat. The...

Two jacks can be distributed between Skat S, player B and player C. Therefore, there are 6 possible options: S(11),B(0),C(0) {two jacks on Skat, player B and C don't have jacks, etc...} S(1),B(1),C(0) S(0),B(11),C(0) S(0),B(1),C(1) S(0),B(0),C(11) S(1),B(0),C(1) this is my sample space, and...

I could expand it by a binomial theorem but I would always arrive at ((1-pi)+pi)^N=1 for any N, why is this expansion important ?

Homework Statement A deck of 32 Skat cards of the four colors clubs, spades, hearts, diamonds in each case ace, king, queen, jack, ten, nine, eight, seven is randomly distributed among three players A, B, C, each player receiving 10 cards and the remaining to cards go to the so-called Skat...

then the generalization to n cases wolud be: P(Bi=n)= N!/(ni!(N-ni)!) pi^ni (1-pi)^(N-ni) ?

I can choose two balls from N in (\stackrel{N}{2}) = N!/(2!(N-2)!) ways, so for two balls it would be : P(Bi=2)= N!/(2!(N-2)!) pi^2 (1-pi)^(N-2) ?

sorry for superscripts/subscripts, yes I meant pi and ni, I have just copy/pasted the problem. Anyway I think that lanedance understood the problem. then for two balls in the ith box (other balls elsewhere but not in ith box): P(Bi=2)=N pi^2 (1-pi)^(N-2) for three balls in the ith box...

Homework Statement Given M boxes as well as N similar (distinguishable) balls. Each single ball is assigned to box i with probability pi, where i = 1...M. All N balls are distributed independently among the M boxes, where as many as desired balls fit into each box. How large is the...

one more thing, what are some applications of density matrices in practice ? (I mean in experimental physics)

Eigenvalues of my matrix are l1=(1-a)/2 and l2=(1+a)/2, 1) trace nonnegative (=sum of eigenvalues) this reduces to (1-a)/2 + (1+a)/2 which gives 1>=0, this condition is met. 2) determinant nonnegative (=product of eigenvalues) (1-a)/2*(1+a)/2>=0 gives a is in the range -1 to 1 (-1 and...

ok, thanks. As an example let's say I have a matrix 1/2((1 ,a),(a,1)) of single spin 1/2 particle at rest. Then for this matrix to be a density matrix conditions (from Ballentine 2.10,2.11,2.12) give me that a=0, and for this matrix to be a pure state matrix condition \rho^{2}=\rho gives...

What are the conditions for some matrix to be a density matrix ? I know of these conditions: 1.) \rho=\rho^{2} 2.) Tr(\rho)=1 (for pure state) Is this all ?

Hi I have fitted Gaussian function to some data in matlab. Now MATLAB gives me this: General model Gauss1: f(x) = a1*exp(-((x-b1)/c1)^2) Coefficients (with 95% confidence bounds): a1 = 2633 (2628, 2637) b1 = 1824 (1824, 1824) c1 =...