It is harder to measure the impact of nonprofits than of for-profits, since you can't just look at their bank balances.
This is one fundamental difficulty of nonprofit work, how to prove that you deserve the investments and not someone else.
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
Liquid nitrogen by Ciro Santilli 40 Updated 2025-07-16
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?
Video 1.
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.
Video 2.
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.
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.
Examples:
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:
Multiple boundary conditions for different parts of the boundary.

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