User mode emulation refers to the ability of certain emulators to emulate userland code running on top of a specific operating system, usually Linux.
For example, QEMU allows you to run a variety of userland ELF programs directly on it, without an underlying Linux kernel running.
User mode emulation is achieved by implementing system calls and special filesystems such as
/dev manually on the emulator one by one.The general tradeoff is that simulation is less acurate as it may lack certain highly advanced kernel functionality you haven't implemented yet. But it is much easier to run executables with it, and you don't have to wait for boot to finish before running, you just run executables directly from the command line.
On one hand, yes, we need knowledge at all levels, and it is fine to start top-to-bottom with an overview.
The problem is, however, that there is a huge knowledge gap between the one liner "this is the truth" and the much more important "this is how we know it, these are the experiments" as mentioned at how to teach and learn physics.
Therefore, if you have that extremely rare knowledge, you should be writing that in addition to the dumbed down version with an open knowledge license. It takes time, but that's what really changes the world.
Ciro Santilli has always felt that there is a huge gap between "the very basic" and "the very advanced", as mentioned at: Section "The missing link between basic and advanced", which existing scientific vulgarization is not doing enough to address. In a sense, filling out this "middle path" is the main goal of OurBigBook.com.
Ciro really enjoyed the description of the "Arindam Kumar Chatterjee" YouTube channel:
Theoretical/mathematical physics at the graduate level and above. This is NOT a popular science channel. Here you find real theoretical physicists doing real theoretical physics. We think it is important for people to get a taste of the real deal, and for aspiring theoretical physicists to see what they are working towards, i.e., to provide the public with something beyond the ubiquitous Michio Kaku and Brian Cox.
One thing must be said however: there seems to be an actual bias against researchers tho try to create vulgarization material: How To Get Tenure at a Major Research University by Sean Carroll (2011), and that is terrible.
There is often more value in a tutorial by a beginner who is trying to fully learn and explain a subject, than by an expert who is trying to "dumb it down" too much.
In "practice" it is likely "useless", because the functions that it can integrate that Riemann can't are just too funky to appear in practice :-)
Its value is much more indirect and subtle, as in "it serves as a solid basis of quantum mechanics" due to the definition of Hilbert spaces.
Here is a more understandable description of the semi-satire that follows: math.stackexchange.com/questions/53969/what-does-formal-mean/3297537#3297537
You start with a very small list of:
- certain arbitrarily chosen initial strings, which mathematicians call "axioms"
- rules of how to obtain new strings from old strings, called "rules of inference" Every transformation rule is very simple, and can be verified by a computer.
Using those rules, you choose a target string that you want to reach, and then try to reach it. Before the target string is reached, mathematicians call it a "conjecture".
Since every step of the proof is very simple and can be verified by a computer automatically, the entire proof can also be automatically verified by a computer very easily.
Finding proofs however is undoubtedly an uncomputable problem.
Most mathematicians can't code or deal with the real world in general however, so they haven't created the obviously necessary: website front-end for a mathematical formal proof system.
The fact that Mathematics happens to be the best way to describe physics and that humans can use physical intuition heuristics to reach the NP-hard proofs of mathematics is one of the great miracles of the universe.
Once we have mathematics formally modelled, one of the coolest results is Gödel's incompleteness theorems, which states that for any reasonable proof system, there are necessarily theorems that cannot be proven neither true nor false starting from any given set of axioms: those theorems are independent from those axioms. Therefore, there are three possible outcomes for any hypothesis: true, false or independent!
Some famous theorems have even been proven to be independent of some famous axioms. One of the most notable is that the Continuum Hypothesis is independent from Zermelo-Fraenkel set theory! Such independence proofs rely on modelling the proof system inside another proof system, and forcing is one of the main techniques used for this.
The landscape of modern Mathematics comic by Abstruse Goose
. Source. This comic shows that Mathematics is one of the most diversified areas of useless human knowledge. There are unlisted articles, also show them or only show them.