When trying to import some files into my Mathematica notebook, I wanted to use ToString to specify the file path. Consider the following MWE, where we export some expression to the directory of the notebook, and immediately import it back: In:= Export]<>"output.txt", 2020]; import1 = Import]<>"output.txt"] Out= "2020" This works ....
What opposes a smooth motion of a rubber eraser on a glass surface?
A metal block smoothly moves on a glass surface. But a rubber eraser doesn't move very smoothly on a glass surface. In each of the cases, the surfaces are smooth at the macroscopic scale. If the latter is due to friction at the molecular level, how come a metal block ....
Seeking very regular $\mathbb Q$-acyclic complexes
This question was raised from a project with Nati Linial and Yuval Peled We are seeking a $3$-dimensional simplicial complex $K$ on $12$ vertices with the following properties a) $K$ has a complete $2$-dimensional skeleton (namely, every triple of vertices form a 2-face of $K$) and it has $165$ $3$-simplices. ....
Berry–Esseen bound for operator norm of matrix averages
Is there a Berry–Esseen bound for operator norm of an average of independent random matrices? Suppose $A_1, \dotsc, A_n$ are independent matrices with $\mathbb{E} = I$ (the identity matrix). Is there a Berry–Esseen bound for properly normalized $\lVert\overline{A} - I\rVert_\text{op}$? ....
How familiar should I be with research topics of a potential PhD supervisor?
I'm about to finish my master's degree in physics (theoretical physics). I'm applying for several professors in Europe. I want to do my PhD in another field than my master's thesis, but both fields are theoretical and to some extend related. But, I didn't take some relevant courses on this ....
Update an application on the click of a Button
I am finishing my first program in Wolfram Mathematica 10 and if I have almost completed is essentially thanks to this valuable forum soon where I will try to help too. Basically, now I have this problem: to make work a routine I used Button]. Unfortunately, in this program you ....
Definition of Lagrange nodes in Gmsh
When gmsh uses higher-order tetrahedral elements, there is an underlying Lagrange basis used to specify the map from reference space to the element. I'm trying to load a gmsh mesh of 3rd degree tetrahedral elements, but I can't seem to find any precise documentation on the location of the nodes ....
Negative Magnus effect?
Supposedly, the Magnus effect, which is responsible for the curve of a curveball, and is the reason that tennis players hit their ground strokes with topspin, only acts above a critical Reynolds number ($\mathrm{Re}=Ud/\nu$, where $U$ is the velocity, $d$ is the diameter, and $\nu$ is the kinematic viscosity) of ....
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. ....
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 ....
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