Why can't $ε_r<1$ (at low frequencies)?
11081
Can relative permittivity be less than 1?
67588
Why does $|e^{ix}|^2 = 1$?
117419
Why is $e^{x}$ not uniformly continuous on $\mathbb{R}$?
48332
Why does the minimum value of $x^x$ equal $1/e$?
70585
Why does Assuming[x > 0, TrueQ[x > 0]] return False?
23969
Why isn't $nxe^{-nx}$ uniformly convergent for $x \geq 0$?
83778
An incorrect proof by exhaustion
29857
Why is this not a violation of parity invarance for EM
97369
Does the limit of $e^{-1/z^4}$ as $z\to 0$ exist?
92421
Negative frequencies: what is that?
150263
Why can't erf be expressed in terms of elementary functions?
77493
Classic $c_r$-inequality in $l_r$ space: $E(|X+Y|^r)\leq c_r[E(|X|^r)+E(|Y|^r)]$
62605
How to find $\mathbb{E}(X\mid\mathbf{1}_{X<Y})$ where $X,Y$ are i.i.d exponential variables?
40160
asymmetric errors with exponential
115400
Negative phantom inside equations
45025
IID Random Variables that are not constant can't converge almost surely
37453
Mgf of double exponential RV