Ciro Santilli @cirosantilli 40

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Python web framework Updated 2025-07-16

virtualenv Updated 2025-07-16

python3 -m pip install --user virtualenv
virtualenv .venv
. .venv/bin/activate
pip install -r requirements.txt

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Electron magnetic moment Updated 2025-07-16

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Problem Book in Quantum Field Theory by Voja Radovanovic (2008) Updated 2025-07-16

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www.springer.com/gp/book/9783540770138

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Quantum Field Theory for The Gifted Amateur by Tom Lancaster (2015) Updated 2025-07-16

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www.amazon.co.uk/Quantum-Field-Theory-Gifted-Amateur/dp/019969933X

People are mostly saying you have to be a more of a genius amateur to read it.

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QuTech Academy Updated 2025-07-16

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One of their learning sites: www.qutube.nl/

The educational/outreach branch of QuTech.

qutechacademy.nl/

www.youtube.com/@QuTechAcademy

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Rack unit Updated 2025-07-16

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Relativistic Quantum Mechanics by Apoorva D Patel (2014) Updated 2025-07-16

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www.youtube.com/playlist?list=PLbMVogVj5nJTDMhThY9xu2Tvg0u1RPuxO

45 1 hour lessons. The Indian traditional music opening is the best.

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Renormalization group Updated 2025-07-16

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ResNet implementation Updated 2025-07-16

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torchvision ResNet
MLperf v2.1 ResNet contains a pre-trained ResNet ONNX at zenodo.org/record/4735647/files/resnet50_v1.onnx for its inference benchmark. We've tested it at: Run MLperf v2.1 ResNet on Imagenette.

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SARS-CoV-2 gene Updated 2025-07-16

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Genes list: www.ncbi.nlm.nih.gov/nuccore/MN908947.3

Some are named after the encoded protein. Others that are not as clean are just orfXXX for open reading frame XXX.

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SQL Updated 2025-07-16

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Up quark Updated 2025-07-16

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Yang-Mills theory Updated 2025-07-16

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Raspberry Pi 1 Updated 2025-07-16

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ResNet variant Updated 2025-07-16

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Saint Peter Updated 2025-07-16

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Brother of andrew the Apostle, called by Jesus in fishers of men. Born Simon, but Jesus renamed him to Peter, thus the weird "Simon called Peter" way he is referred to as in some versions of the Bible.

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Sandy Lerner nude photo Updated 2025-07-16

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She posed naked on horseback for Forbes to promote animal rights in 1997.

A ultra low resolution reproduction of the image can be found at: rohitnair.wordpress.com/2011/12/13/cisco-history-cisco-systems-history-and-trivia-brand-history-and-trivia/

She's kind of lying on top of the horse's back, and you can't see much, just some tastefully light erotica. It's not like she's fucking the horse or anything.

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Sequoia Capital Updated 2025-07-16

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Video 1.

Target Big Markets by Don Valentine (2010)

Source.

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Term symbols for carbon ground state Updated 2025-07-16

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This example covered for example at Video 1. "Term Symbols Example 1 by TMP Chem (2015)".

Carbon has electronic structure 1s2 2s2 2p2.

For term symbols we only care about unfilled layers, because in every filled layer the total z angular momentum is 0, as one electron necessarily cancels out each other:

magnetic quantum number varies from -l to +l, each with z angular momentum $- l ℏ$ to $+ l ℏ$ and so each cancels the other out
spin quantum number is either + or minus half, and so each pair of electron cancels the other out

So in this case, we only care about the 2 electrons in 2p2. Let's list out all possible ways in which the 2p2 electrons can be.

There are 3 p orbitals, with three different magnetic quantum numbers, each representing a different possible z quantum angular momentum.

We are going to distribute 2 electrons with 2 different spins across them. All the possible distributions that don't violate the Pauli exclusion principle are:

m_l  +1  0 -1  m_L  m_S
     u_ u_ __    1    1
     u_ __ u_    0    1
     __ u_ u_   -1    1
     d_ d_ __    1   -1
     d_ __ d_    0   -1
     __ d_ d_   -1   -1
     u_ d_ __    1    0
     d_ u_ __    1    0
     u_ __ d_    0    0
     d_ __ u_    0    0
     __ u_ d_   -1    0
     __ d_ u_   -1    0
     ud __ __    2    0
     __ ud __    0    0
     __ __ ud   -2    0

where:

m_l is $m_{l}$ , the magnetic quantum number of each electron. Remember that this gives a orbital (non-spin) quantum angular momentum of $m_{l} ℏ$ to each such electron
m_L with a capital L is the sum of the $m_{l}$ of each electron
m_S with a capital S is the sum of the spin angular momentum of each electron

For example, on the first line:

m_l  +1  0 -1  m_L  m_S
     u_ u_ __    1    1

we have:

one electron with $m_{l} = + 1$ , and so angular momentum $ℏ$
one electron with $m_{l} = + 0$ , and so angular momentum 0

and so the sum of them has angular momentum

0 + 1ℏ = 1ℏ

. So the value of

m_{L}

is 1, we just omit the

ℏ

TODO now I don't understand the logic behind the next steps... I understand how to mechanically do them, but what do they mean? Can you determine the term symbol for individual microstates at all? Or do you have to group them to get the answer? Since there are multiple choices in some steps, it appears that you can't assign a specific term symbol to an individual microstate. And it has something to do with the Slater determinant. The previous lecture mentions it: www.youtube.com/watch?v=7_8n1TS-8Y0 more precisely youtu.be/7_8n1TS-8Y0?t=2268 about carbon.

youtu.be/DAgEmLWpYjs?t=2675 mentions that

^{3} D

is not allowed because it would imply

L = 2, S = 1

, which would be a state uu __ __ which violates the Pauli exclusion principle, and so was not listed on our list of 15 states.

He then goes for

^{1} D

and mentions:

S = 1 so $m_{S}$ can only be 0
L = 2 (D) so $m_{L}$ ranges in -2, -1, 0, 1, 2

and so that corresponds to states on our list:

ud __ __    2    0
u_ d_ __    1    0
u_ __ d_    0    0
__ u_ d_   -1    0
__ __ ud   -2    0

Note that for some we had a two choices, so we just pick any one of them and tick them off off from the table, which now looks like:

 +1  0 -1  m_L  m_S
 u_ u_ __    1    1
 u_ __ u_    0    1
 __ u_ u_   -1    1
 d_ d_ __    1   -1
 d_ __ d_    0   -1
 __ d_ d_   -1   -1
 d_ u_ __    1    0
 d_ __ u_    0    0
 __ d_ u_   -1    0
 __ ud __    0    0

Then for