FluidSynth Updated +Created
Supports only very basic effects it seems: chorus effect and reverberation. The main way to add instruments to it is via SoundFont files.
General linear group Updated +Created
Invertible matrices. Or if you think a bit more generally, an invertible linear map.
When the field is not given, it defaults to the real numbers.
Non-invertible are excluded "because" otherwise it would not form a group (every element must have an inverse). This is therefore the largest possible group under matrix multiplication, other matrix multiplication groups being subgroups of it.
Greenberger-Horne-Zeilinger state Updated +Created
Group extension problem Updated +Created
Besides the understandable Wikipedia definition, Video "Simple Groups - Abstract Algebra by Socratica (2018)" gives an understandable one:
Given a finite group and a simple group , find all groups such that is a normal subgroup of and .
In particular, this is hard because you can't just take the direct product of groups to retrieve the original group: Section "Relationship between the quotient group and direct products".
Group of American universities Updated +Created
Group of Lie type Updated +Created
In the classification of finite simple groups, groups of Lie type are a set of infinite families of simple lie groups. These are the other infinite families besides te cyclic groups and alternating groups.
A decent list at: en.wikipedia.org/wiki/List_of_finite_simple_groups, en.wikipedia.org/wiki/Group_of_Lie_type is just too unclear. The groups of Lie type can be subdivided into:
The first in this family discovered were a subset of the Chevalley groups by Galois: , so it might be a good first one to try and understand what it looks like.
TODO understand intuitively why they are called of Lie type. Their names , seem to correspond to the members of the classification of simple Lie groups which are also named like that.
But they are of course related to Lie groups, and as suggested at Video "Yang-Mills 1 by David Metzler (2011)" part 2, the continuity actually simplifies things.
Maxwell's equations in curved spacetime Updated +Created
Rho Updated +Created
This one is a little confusing: the upper case looks exactly like a letter P, but as the name suggests, it actually corresponds to the letter R. The letter P corresponds to pi instead.
ANN model Updated +Created
Classification of closed surfaces Updated +Created
So simple!! You can either:
A handle cancels out a Möbius strip, so adding one of each does not lead to a new object.
You can glue a Mobius strip into a single hole in dimension larger than 3! And it gives you a Klein bottle!
Intuitively speaking, they can be sees as the smooth surfaces in N-dimensional space (called an embedding), such that deforming them is allowed. 4-dimensions is enough to embed cover all the cases: 3 is not enough because of the Klein bottle and family.
Grinding for software interviews Updated +Created
If your kids are about to starve, fine, do it.
But otherwise, Ciro Santilli will not, ever, spend his time drilling programmer competition problems to join a company, life is too short for that.
Life is too short for that. Companies must either notice that you can make amazing open source software projects or contributions, and hire you for that, or they must fuck off.
Companies must either notice that you can make amazing projects or contributions, and hire you for that, or they must fuck off.
Guqin Updated +Created
Figure 2.
11th century painting of a guqin recital
. Source.
Figure 3.
Stringless guqin fan painting by Feng Chaoran (1943)
Stolen traight from www.silkqin.com/10ideo.htm on silkqin.com:
Wind in the pines and a babbling brook are nature's melody. A qin was brought along, but there is no need to play it
The The Gateless Barrier vibe and Chinese naturalism is just awesome.
Software reverse engineering tool Updated +Created
Unit and system tests Updated +Created
Antimicrobial Updated +Created
Bilinear map Updated +Created
Linear map of two variables.
More formally, given 3 vector spaces X, Y, Z over a single field, a bilinear map is a function from:
that is linear on the first two arguments from X and Y, i.e.:
Note that the definition only makes sense if all three vector spaces are over the same field, because linearity can mix up each of them.
The most important example by far is the dot product from , which is more specifically also a symmetric bilinear form.
Dwarf Fortress Updated +Created
Made by a single dude. As SsethTzeentach puts it, this is the greatest autism project ever made.

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