Physics

### Do atoms behave like waves?

I've heard someone state that the double slit experiment can also be done with atoms, not just electrons or photons of light. .... Aaron: 4 hours ago

Biology

### Are there examples of animals being sexually attracted to another species more than to their own?

I just thought that from the perspective of a female domestic cat, a male bobcat probably looks like the archetype of a perfect mate. As tall, strong, muscular and mighty as it possibly gets. Clearly preferable to any of these boring male domestics. Has anyone ever done any research on .... Thomas: 4 hours ago

Math

Let $\omega(n)$ the number of distinct prime factors of $n$ (counted without multiplicity). A famous consequence of Turán–Kubilius inequality is $$\sum_{n\leq x}(\omega(n)-\log\log x)^2=O(x\log \log x).$$ However, I am interested in a small variation of the previous result. Indeed, I would like to obtain a similar result to $$.... Sadie: 4 hours ago Math ### Finding the Levy triplet of a Levy process I know the levy triplet of a Poisson process N_t- (0,0,\lambda\delta_{1}(y)) and its characteristic function is \phi_N=exp and also that of the standard \alpha stable subordinator D_t - (\frac{iu\alpha}{\Gamma(1-\alpha)},0,\frac{\alpha}{\Gamma(1-\alpha)}y^{-\alpha-1}dy) and its characteristic function is \phi_{D}(u)=exp My question is how do I find the triplet of (N_t,D_t) where N_t and D_t .... Emma: 4 hours ago Physics ### Expansion of Helmholtz energy To get an expansion of Helmholtz energy of a) an ideal gas b) a Van der waals gas we must integrate \left ( \frac{\delta A }{\delta V} \right )_{T}=-P I saw the solution is : Can you explain why is that? .... Christopher: 4 hours ago Physics ### Uncertainty in parenthesis In a physics text book I read the following:$$e/m=1.758820150(44) ×10^{11} \mathrm{C/kg} $$In this expression, (44) indicates the likely uncertainty in the last two digits, 50. How should I understand this uncertainty? Does it mean \pm 44 on the last two digits? .... Alice: 4 hours ago History ### What was the Nature of Resistance in 1938 Czechoslovakia? I wonder if someone might help me. I'm writing a novel. My protagonist is a dual national (English born, German parents) bio chemist contracted to work for Freiburg University (http://en.wikipedia.org/wiki/University_of_Freiburg) 1938. At the time science is deemed useful only if it is practical and he is ordered to travel regularly .... Gabriella: 4 hours ago Computer Science ### Does the k-th approximate solution of a stationary iteration belong to the k-th Krylov subspace? For an stationary iteration method solving Ax=b as follows:$$ Mx_k = Nx_{k-1}+b,  I have known that when $M = I$, i.e., the Richardson iteration, the k-th solution $x_k = x_{k-1}+r_{k-1}$ is in the k-th Krylov subspace $K_k(A,b)$ with $x_0=0$. So, if we use a Krylov subspace method e.g., .... Harper: 4 hours ago

Physics

### How does one apply Gauss's Law when dealing with two infinite planes?

If you have two parallel planes with one density of 1 C/m^2 and the other with -1 C/m^2 density and you need to find the electric field at a point in the middle, how do you use Gauss's Law? I drew a box enclosing one plane to find the electric .... Nova: 4 hours ago

Physics

### How is the phase of a BEC changing when some particles are being removed?

I have some trouble understanding what happens to the phase of a BEC when some particles are removed. The motivation of the question is the experiment of observing interference between two BECs. In my current picture, a BEC is a state $\Phi(r)e^{i\varphi}$, where $\Phi(r)$ is the N-fold tensorproduct of the .... Olivia: 4 hours ago