Einstein notation for partial derivatives by
Ciro Santilli 35 Updated 2025-04-24 +Created 1970-01-01
The Einstein summation convention works will with partial derivatives and it is widely used in particle physics.
In particular, the divergence and the Laplacian can be succinctly expressed in this notation:
In order to express partial derivatives, we must use what Ciro Santilli calls the "partial index partial derivative notation", which refers to variables with indices such as , , , , and instead of the usual letters , and .
Disk encryption password handover plausible deniability by
Ciro Santilli 35 Updated 2025-04-24 +Created 1970-01-01
Can the last disk access times be checked via forensic methods?
The matrix ring of degree n is the set of all n-by-n square matrices together with the usual vector space and matrix multiplication operations.
Mitochondria have DNA because they need to be controlled individually by
Ciro Santilli 35 Updated 2025-04-24 +Created 1970-01-01
Argued at Power, Sex, Suicide by Nick Lane (2006) page 212.
Basically, energy supply has to be modulated rather quickly, because we spend a lot sometimes, and very little other times.
Even not turning it off quickly enough is a problem, as it starts to generate free radicals which fuck you up.
If control came from the nucleus, it has no way to address different mitochondria. But it might be that only one of the mitochondria needs the change. If the nucleus tells all mitochondria to stop producing when only one is full, the others are going to say: "nope, I'm not full, continue producing!" and the one that need to stop will have its signal overridden by the others.
E.g. thinking about the electric potential alone, you could set the zero anywhere, and everything would remain be the same.
The Lorentz gauge is just one such choice. It is however a very popular one, because it is also manifestly Lorentz invariant.
For an example with context, have a look at E. Coli K-12 MG1655 and the second protein of the genome, e. Coli K-12 MG1655 gene thrA.
Used for example:
- by Monero to hide the input of a transaction
- anonymous electronic voting
Pinned article: ourbigbook/introduction-to-the-ourbigbook-project
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This feature makes it possible for readers to find better explanations of any topic created by other writers. And it allows writers to create an explanation in a place that readers might actually find it.Figure 1. Screenshot of the "Derivative" topic page. View it live at: ourbigbook.com/go/topic/derivativeVideo 2. OurBigBook Web topics demo. Source. - local editing: you can store all your personal knowledge base content locally in a plaintext markup format that can be edited locally and published either:This way you can be sure that even if OurBigBook.com were to go down one day (which we have no plans to do as it is quite cheap to host!), your content will still be perfectly readable as a static site.
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