Questions tagged [conventions]
A convention is a set of agreed, stipulated, or generally accepted norms. It typically helps common efficiency or understanding but is not required, as opposed to a strict standard or protocol.
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Normalization Factor and Sign of Exponential Term in Fourier Transform [closed]
I have two questions regarding the Fourier transform:
Normalization factor: Some texts use no normalization factor in the definition of the Fourier transform, while others use $1/\sqrt2\pi$. What is ...
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How Can there be a Gravitational Potential when there is NO Gravitational Field? [closed]
How does it make any logic that there exist a potential when there is no net field
for example when we have a Hollow Sphere with mass we can find out the the gravitational *potential inside the sphere ...
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How to avoid symbol confusion when discussing both wavelengths and eigenvalues? [closed]
I'm about to start writing a larger assignment where I need to describe both wavelengths and eigenvalues. Traditionally, both of these are represented by $\lambda$, which can be confusing.
Do you have ...
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What's the difference? $\nabla_\mu e_\nu=\Gamma_{\mu \nu}^\rho e_\rho~\text{ and }~\partial_\mu e_\nu=\Gamma_{\mu \nu}^\rho e_\rho~?$
What's the difference? $$\nabla_\mu e_\nu=\Gamma_{\mu \nu}^\rho e_\rho~\text{ and }~\partial_\mu e_\nu=\Gamma_{\mu \nu}^\rho e_\rho~?$$
In John Dirk Walecka's book 'Introduction to General Relativity',...
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Why is work done by force $+mgh$ in the situation of throwing something up?
If there is a particle at point A(at rest) and a force moves it to point B(Above point A vertically)(final velocity = 0 at this point), the work done by gravity is $-mgh$. This I understand as the ...
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Significant figures when product is more by a factor of 10
A rectangular plate has a length of 21.3 cm and a width of 9.8 cm. Calculate the area of the plate.
A straightforward question, which you multiply and arrive at 208.74 cm2. Taking significant figures ...
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$CP$-transformation for fermionic bilinears
I am trying to derive the transformation of the fermionic bilinear $\bar{\psi}\psi$ under $CP$ transformation.
I know that $P$ acts as:
$$\psi(t, \vec{x}) \xrightarrow{P} \gamma^0 \psi(t, -\vec{x})$$
...
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Equation for real/complex $\phi^4$ theory
On wikipedia (see this link), the Lagrangians of the $\phi^4$ equation for real AND complex scalar fields are given. One may derive the Klein-Gordon equation by inserting into the Euler-Lagrange-...
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Why did we choose Coulomb's constant $k$ as $9\cdot10^9 \rm Nm^2/C^2$ while define unit of charge instead of any other number?
I understand that while defining charge, Coulomb had to choose any arbitrary value of $k$ to describe unit of charge. But, why did we chose $9\cdot10^9 \rm Nm^2/C^2$ as the value of $k$, but not any ...
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