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Understand and explain amazingly every single Nobel Prize in physics, chemistry and biology. Since in particular the Nobel Foundation is unable to do that for any at all, especially of the key old ones, e.g. www.nobelprize.org/prizes/physics/1965/summary/. Hopeless.
To be fair, those in theoretical physics at least basically come down to reading a bunch of books. But perhaps anything slightly more experimental could have
77K. Low enough for "high temperature superconductors" such as yttrium barium copper oxide, but for "low temperature superconductors", you need to go much lower, typically with liquid helium, which is likely much more expensive. TODO by how much?
Where Do You Get Liquid Nitrogen? by The King of Random (2016)
Source. He just goes to a medical gases shop in a local industrial estate and buys 20L for 95 dollars and brings it back on his own Dewar marked 35LD.Making Liquid Nitrogen From Scratch! by Veritasium (2019)
Source. "From scratch" is perhaps a bit clickbaity, but I'll take it.Sets both a Dirichlet boundary condition and a Neumann boundary condition for a single part of the boundary.
Can be used for hyperbolic partial differential equations.
We understand intuitively that this imposes stricter requirements on solutions, which makes it easier to guarantee uniqueness, but also harder to have existence. TODO intuitively why hyperbolic need this extra level of restriction.
Linear combination of a Dirichlet boundary condition and Neumann boundary condition at each point of the boundary.
Examples:
- In this case, the normal derivative at the boundary is proportional to the difference between the temperature of the boundary and the fixed temperature of the external environment.The result as time tends to infinity is that the temperature of the plaque tends to that of the environment.
In the context of wave-like equations, an open-boundary condition is one that "lets the wave go through without reflection".
This condition is very useful when we want to simulate infinite domains with a numerical method. Ciro Santilli wants to do this all the time when trying to come up with demos for his physics writings.
Here are some resources that cover such boundary conditions:
- www.asc.tuwien.ac.at/~arnold/pdf/graz/graz.pdf lots of slides
- hplgit.github.io/wavebc/doc/pub/._wavebc_cyborg002.html mentions them and gives a 1D formula. It mentions that things get complicated in 2D and 3D TODO why.The other page: hplgit.github.io/wavebc/doc/pub/._wavebc_cyborg003.html shows solution demos.
Multiple boundary conditions for different parts of the boundary.
Pinned article: Introduction to the OurBigBook Project
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