Ever since @JesseJenkins and colleagues work on a zero carbon US and this work by @DrChrisClack and colleagues on incorporating DER, I've been having the following set of thoughts about how to reduce the risk of failure in a US clean energy buildout. Bottom line is much more DER.

Today, we are bringing other exciting results involving black holes and AI. We released a new paper:

"Black Hole Weather Forecasting with Deep Learning: A Pilot Study"

Work by Roberta Duarte (@import_robs), Rodrigo Nemmen (@nemmen) and João Paulo Navarro (from @NVIDIABrasil).

The authors used deep learning to simulate the dynamics of gas accreting onto a black hole, i.e., black hole weather forecasting.

They trained the model (U-Net) with frames from numerical solutions of the hydrodynamical equations.

Numerical simulations are time-consuming. A simple simulation can take as long as 7 days to finish. If we go with more complex simulations, this time may increase.

We want to investigate if deep learning can be a new method to simulate accurately in less time!

In the paper, they discussed two examples:

1- The model simulating only one system after learning only from this system
2- The model simulating an unseen system after training with several systems with different initial conditions

In the first example, they trained the model with a single system and analyzed how the model simulates by iterative predictions.

The result is that the model can simulate up to 8e4 gravitational time accurately with a speed-up of 30000x faster!

In a number of Sunday papers:
Scientific advisers said it was “hard to see” when the restrictions would end as new variants continued to emerge, delivering a potentially devastating blow to the travel industry. The prime minister said that after progress with vaccinations...

...”what we don’t want to see is all that work undone by the arrival of a new variant that is vaccine-busting”.
The idea is planted in people’s mind that this virus is mutating in such a way as to evade prior immunity. This is completely unfounded, certainly as regards immunity..

...gained naturally, after repelling the virus (which well around 99.9% of the population do, fewer, obviously in the very elderly & already ill, more in those younger & well). It’s important to appreciate that upon infection, the human immune system cuts up an infectious...

...agent into short pieces. Each of these short pieces of protein are presented to other cells in the immune system, like an identity parade. Our cells have a truly astonishing range of abilities to recognise different protein structures, and there will be some which recognise...

...each of the pieces of the invader. The cells which recognise a piece are instructed to multiply selectively so that, after a few days to a couple of weeks, our bodies contain large numbers of virus piece specific cells. These have a range of functions. Some make antibodies...

Did you know that all the nuclear bombs we exploded in the '40s-50s-60s have permanently contaminated all the steel the world has produced since then? All steel in the world is divided into two categories: pre-1945 non-contaminated steel, and post-1945 contaminated steel.

How?

Nuclear bombs (including the tests) create a lot of radioisotopes that are not found in nature. For example Cobalt-60 (a radioactive version of Cobalt-59). And since the 1945 Trinity test, these have all dispersed in the atmosphere.

What does this have to do with steel?

The process of manufacturing steel uses atmospheric air (or atmospheric oxygen). Some of the radioisotopes like Cobalt-60 get pulled in too, and as a result, any steel produced after 1945 has embedded in it some of these radioisotopes, sitting there emitting gamma rays.

Why do we care about traces of radioisotopes in steel? When making Geiger counters, or medical devices to check for radioactive contamination, or astronomical instruments, the emissions from the contaminated steel would interfere with the measurements.

So we need pre-1945 steel

Pre-1945 non-contaminated steel is called "low background steel". And when we need it, where do we get it from?

We go, find pre-World-War-II sunken shipwrecks, and then salvage the steel (and lead) from those to build our instruments which need heavy radiation shielding.