• battery life:
    • 2023-04: on-browser streaming + light browsing on Ubuntu 22.10: about 2h45. Too low! Gotta try buying a new battery.
  • 2022-01-04 updated firmward after noticing that ubuntu 21.10 does not wake up from suspend seemed to happen every time when not connected to external power. dmidecode diff excerpt:
     BIOS Information
            Vendor: LENOVO
    -       Version: N1UET40W (1.14 )
    -       Release Date: 09/28/2017
    +       Version: N1UET71W (1.45 )
    +       Release Date: 07/18/2018
    used the "Ubuntu Software" GUI as mentioned at: support.lenovo.com/gb/en/solutions/ht510810-how-to-do-software-updates-linux. Kudos for making this accessible to newbs.
    After doing that, another update became available to: 0.1.56, clicked it and was much faster than the previous one, and didn't auto reboot. After manual reboot, dmidecode diffed again:
     BIOS Information
            Vendor: LENOVO
    -       Version: N1UET71W (1.45 )
    -       Release Date: 07/18/2018
    +       Version: N1UET82W (1.56 )
    +       Release Date: 08/12/2021
    plus a bunch of other lines.
  • 2021-06-05 upgraded to Ubuntu 21.04 with a clean install from an ISO. Selected
    • "Minimal installation"
    • "Erase disk and install Ubuntu". Notably, this erased the Microsoft Windows that came with the computer and was never used not even once
    • "Erase disk ans use ZFS"
    • Encrypt the new Ubuntu installation for security
    After this, the GUI felt fast, who would have thought that erasing a bunch of stuff would make the system faster!
    lsblk contains:
    zd0               230:0    0   500M  0 disk
    └─keystore-rpool  253:0    0   484M  0 crypt /run/keystore/rpool
    nvme0n1           259:0    0 476.9G  0 disk
    ├─nvme0n1p1       259:1    0   512M  0 part  /boot/efi
    ├─nvme0n1p2       259:2    0     2G  0 part
    │ └─cryptoswap    253:1    0     2G  0 crypt
    ├─nvme0n1p3       259:3    0     2G  0 part
    └─nvme0n1p4       259:4    0 472.4G  0 part
    and lsblk -f:
    zd0               crypto_LUKS 2
    └─keystore-rpool  ext4        1.0   keystore-rpool
    nvme0n1
    ├─nvme0n1p1       vfat        FAT32
    ├─nvme0n1p2       crypto_LUKS 2
    │ └─cryptoswap
    ├─nvme0n1p3       zfs_member  5000  bpool
    └─nvme0n1p4       zfs_member  5000  rpoo
    Then:
    grep '[rb]pool' /proc/mounts
    contains:
    rpool/ROOT/ubuntu_uvs1fq / zfs rw,relatime,xattr,posixacl 0 0
    rpool/USERDATA/ciro_czngbg /home/ciro zfs rw,relatime,xattr,posixacl 0 0
    rpool/USERDATA/root_czngbg /root zfs rw,relatime,xattr,posixacl 0 0
    rpool/ROOT/ubuntu_uvs1fq/srv /srv zfs rw,relatime,xattr,posixacl 0 0
    rpool/ROOT/ubuntu_uvs1fq/usr/local /usr/local zfs rw,relatime,xattr,posixacl 0 0
    rpool/ROOT/ubuntu_uvs1fq/var/games /var/games zfs rw,relatime,xattr,posixacl 0 0
    rpool/ROOT/ubuntu_uvs1fq/var/log /var/log zfs rw,relatime,xattr,posixacl 0 0
    rpool/ROOT/ubuntu_uvs1fq/var/lib /var/lib zfs rw,relatime,xattr,posixacl 0 0
    rpool/ROOT/ubuntu_uvs1fq/var/mail /var/mail zfs rw,relatime,xattr,posixacl 0 0
    rpool/ROOT/ubuntu_uvs1fq/var/snap /var/snap zfs rw,relatime,xattr,posixacl 0 0
    rpool/ROOT/ubuntu_uvs1fq/var/www /var/www zfs rw,relatime,xattr,posixacl 0 0
    rpool/ROOT/ubuntu_uvs1fq/var/spool /var/spool zfs rw,relatime,xattr,posixacl 0 0
    rpool/ROOT/ubuntu_uvs1fq/var/lib/AccountsService /var/lib/AccountsService zfs rw,relatime,xattr,posixacl 0 0
    rpool/ROOT/ubuntu_uvs1fq/var/lib/NetworkManager /var/lib/NetworkManager zfs rw,relatime,xattr,posixacl 0 0
    rpool/ROOT/ubuntu_uvs1fq/var/lib/apt /var/lib/apt zfs rw,relatime,xattr,posixacl 0 0
    rpool/ROOT/ubuntu_uvs1fq/var/lib/dpkg /var/lib/dpkg zfs rw,relatime,xattr,posixacl 0 0
    bpool/BOOT/ubuntu_uvs1fq /boot zfs rw,nodev,relatime,xattr,posixacl 0 0
    which gives an idea of how the above map to mountpoints.
    Had two GUI freezes since installation, a fixed images shows no matter what I do, possibly graphics only, but impossible to tell (next time I'll try SSH access). No Nvidia drivers installed yet.
2020-06-06: dropped some lemon juice on the bottom left of touchpad. Bottom left button not working anymore... I'm an idiot. There are many other alternatives, but very aggravating, I'll replace it for sure. Can't find the exact replacement part or any videos showing its replacement online easliy, dang. For the T430: www.youtube.com/watch?v=F3lzV9uXRjU Asked at: forums.lenovo.com/t5/ThinkPad-P-and-W-Series-Mobile-Workstations/P51-left-bottom-button-below-trackpad-mouse-left-click-stopped-working-possible-to-replace/m-p/5019903 Also I could not access it because you need to remove the HDD first: www.youtube.com/watch?v=5Klawxc7T_Y and I can't pull it out even with considerable force, unlike in the video... And OMG, those button caps are impossible to re-install once removed!!! Then when I put the whole thing back together, the upper buttons were not working anymore. FUUUUUUUUCK. When first opening I pulled on it without properly removing the cap and it came off, but it didn't look broken in any way and I put it back in. Keyboard works thank God, so right black connector is fine, left white one oppears to be the one for upper keys and trackpoint, both of which stopped working. The hardware manual confirms that they are both part of the same device, so basically a mouse :-) TODO can it be bought separately from te keyboard? Doesn't look like it, photo of keyboard part includes those buttons. The manual also confirms that the bottom buttons are one device with the trackpad "trackpad with buttons", thus forming the second entire mouse.
2019-04-17: popup asking about "ThinkPad P51 Management Engine Update" from from 182.29.3287 to 184.60.3561, said yes.
Ubuntu 17.10 setup after buying it:
Battery life shown by Ubuntu battery app after installation:
  • before NVIDIA driver setup: 8h
  • after: 6.5h
Continuum mechanics is a branch of mechanics that deals with the behavior of materials modeled as continuous mass rather than as discrete particles. It provides a framework for understanding how materials deform and respond to forces when they are subjected to stress, temperature changes, or other influences.
Hypatia of Alexandria was a renowned mathematician, astronomer, and philosopher who lived during the late 4th and early 5th centuries CE. She is often celebrated as one of the first female scientists in history and a symbol of intellectual pursuit in a time of cultural and religious upheaval. Her life and legacy have inspired various cultural depictions in literature, art, film, and other media.
The term "essentially unique" is often used in various contexts, such as mathematics, philosophy, and other fields, to describe an object, solution, or concept that is unique in a certain essential way, even if it is not unique in every possible way. In mathematics, for instance, an "essentially unique" solution refers to a solution that may not be the only one in a strict sense but is the one that matters for the given problem or context.
Hypercomplex numbers extend the concept of complex numbers to higher dimensions. While complex numbers can be represented in the form \( a + bi \), where \( a \) and \( b \) are real numbers and \( i \) is the imaginary unit satisfying \( i^2 = -1 \), hypercomplex numbers involve additional dimensions and may introduce multiple imaginary units.

Pinned article: Introduction to the OurBigBook Project

Welcome to the OurBigBook Project! Our goal is to create the perfect publishing platform for STEM subjects, and get university-level students to write the best free STEM tutorials ever.
Everyone is welcome to create an account and play with the site: ourbigbook.com/go/register. We belive that students themselves can write amazing tutorials, but teachers are welcome too. You can write about anything you want, it doesn't have to be STEM or even educational. Silly test content is very welcome and you won't be penalized in any way. Just keep it legal!
We have two killer features:
  1. topics: topics group articles by different users with the same title, e.g. here is the topic for the "Fundamental Theorem of Calculus" ourbigbook.com/go/topic/fundamental-theorem-of-calculus
    Articles of different users are sorted by upvote within each article page. This feature is a bit like:
    • a Wikipedia where each user can have their own version of each article
    • a Q&A website like Stack Overflow, where multiple people can give their views on a given topic, and the best ones are sorted by upvote. Except you don't need to wait for someone to ask first, and any topic goes, no matter how narrow or broad
    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/derivative
  2. 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.
    Figure 2.
    You can publish local OurBigBook lightweight markup files to either https://OurBigBook.com or as a static website
    .
    Figure 3.
    Visual Studio Code extension installation
    .
    Figure 4.
    Visual Studio Code extension tree navigation
    .
    Figure 5.
    Web editor
    . You can also edit articles on the Web editor without installing anything locally.
    Video 3.
    Edit locally and publish demo
    . Source. This shows editing OurBigBook Markup and publishing it using the Visual Studio Code extension.
    Video 4.
    OurBigBook Visual Studio Code extension editing and navigation demo
    . Source.
  3. https://raw.githubusercontent.com/ourbigbook/ourbigbook-media/master/feature/x/hilbert-space-arrow.png
  4. Infinitely deep tables of contents:
    Figure 6.
    Dynamic article tree with infinitely deep table of contents
    .
    Descendant pages can also show up as toplevel e.g.: ourbigbook.com/cirosantilli/chordate-subclade
All our software is open source and hosted at: github.com/ourbigbook/ourbigbook
Further documentation can be found at: docs.ourbigbook.com
Feel free to reach our to us for any help or suggestions: docs.ourbigbook.com/#contact