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 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 Thomas: 4 hours ago

Math

A variant of Turán–Kubilius inequality

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 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 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 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 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 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 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 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 Olivia: 4 hours ago