Sal

Sal, 20 days ago

I can download the app and test a few things tomorrow. Maybe when the server is rebooted it logs users out for some reason. I am not sure.

Do you have accounts in other servers that do not get disconnected?

Sal, 29 days ago (edited 22 days ago)

Awesome! The one with the sustained source loop is my favorite:

https://mander.xyz/pictrs/image/684c5215-1be3-4537-8100-11c33a374656.png

Also, the one that shoots out flames paints a picture similar to how a synchrotron behaves, shooting out X-rays into the beamlines as the electron bunches move around.

https://mander.xyz/pictrs/image/b7870ecb-bd83-4506-a303-0ac20bc61ecd.png

https://mander.xyz/pictrs/image/897baadc-dddc-4759-89ae-d58ba42873df.png

Upon looking into it closer, the synchrotron is a bit of a mixture of those two concepts - the source loop (booster ring) that is fed by the linear accelerator, and then the larger loop (storage room) that feeds X-rays the beamlines. Of course, many details differ, but still it is interesting to notice the similarities !

Sal, 1 month ago

Very nice article! Thanks :D

Sal, 2 months ago

The error I see is a “bad image format” response from the PlantNet API. I zoomed in, took a screenshot, and re-uploaded it to imgur and it worked.

From the FAQ: " The ideal image size is 800 pixels for the small side, or otherwise 1280 pixels for the large side. "

This image is 259x194, so I think that is why it is rejected.

Sal, 2 months ago

If the timing is right, I would bring a mushroom grow bag with mushrooms sprouting.

If not… probably my radiacode gamma spectrometer and some of my radioactive items. Maybe a clock with radium painted dials and a piece of trinitite. I think that there are many different points of discussion that can be of interest to a broad audience (radioactivity, spectroscopy, electronics, US labor law story of the radium girls, nuclear explosions, background radiation… etc). As a bonus I can bring a UV flash light and show the radium fluorescence. Adults love UV flash lights.

Sal, 2 months ago (edited 1 month ago)

I think that they are referring to Paxillus involotus

It is quite an interesting mushroom. It was considered “safe to eat” for a long time, but it contains an antigen that a human’s immune system can learn to attack.

The antigen is still of unknown structure but it stimulates the formation of IgG antibodies in the blood serum.

I once looked into whether this immune response builds up over many exposures, or if it is a random event that has a probability of happening for each exposure. I don’t remember finding a convincing answer… If it is a random event, then mushroom could be considered a “Russian roulette” mushroom that will usually provide a nice meal, but, if unlucky, you may experience the following:

Poisoning symptoms are rapid in onset, consisting initially of vomiting, diarrhea, abdominal pain, and associated decreased blood volume. Shortly after these initial symptoms appear, hemolysis develops, resulting in reduced urine output, hemoglobin in the urine or outright absence of urine formation, and anemia. Hemolysis may lead to numerous complications including acute kidney injury, shock, acute respiratory failure, and disseminated intravascular coagulation. These complications can cause significant morbidity with fatalities having been reported.

I agree with you that this is probably unrelated to the “generally similar to humans” comment. I feel like this fantasy is a combination of the above fact mixed in with the fact that the Fungi belong to the Opisthokonts, which places them closer to animals than plants, and so they share some interesting cellular characteristics with us. This places them closer to animals than plants, but “generally similar to humans” is perhaps a bit of a stretch ^_^

But, it is just a meme about a guy being hyped about mushrooms. Hopefully people don’t expect memes to be super accurate 😁

Sal, 2 months ago

Oh wow, this would be great. I set up my XMPP server with Prosody because that seemed like the most straight forward choice. But now I wonder whether it is worth to reconsider and look into Ejabberd.

Sal, 2 months ago

Thanks! I’ll have a look

Sal, 1 month ago (edited 1 month ago)

If carbon dioxide (CO2) simply absorbed energy, including sunlight, without re-emitting it, it could lead to cooling at the Earth’s surface. This is because the absorbed energy would not be radiated back to the surface, resulting in a net loss of energy from the Earth-atmosphere system.

Hmm, I don’t follow the argument. If the CO2 and other atmospheric molecules were unable to re-emit the light, they would need to dissipate the excess energy via non-radiative processes. So the main transfer of energy to the surroundings would be via collisions with other molecules. The density of molecules is greater as you approach the surface, and the density in space is very very low. So there are many more molecules to collide with that move the energy in the direction of the surface, and there is no easy pathway to get the heat out of the earth, other than hot molecules diffusing into space.

So, unless there is an important hole in my reasoning, removing the radiative pathway would ultimately result in a hotter earth because a larger percentage of the energy of light is trapped.

I think that the main problem in your comment is that it does not account for what happens to the energy that is absorbed. This energy does not disappear - you need to account for it.

Sal, 1 month ago

Ah, I see what you mean.

The experiment showed that the CO2 gas was an efficient absorber of some form of radiant energy that came from the sun. We now know that this energy is infrared radiation. This radiation is emitted by hot bodies, and the sun emits a lot of it.

But yes, you are correct in that her experiment was not about the greenhouse effect itself - which includes more complicated interactions such as the reflection and emission of IR from the earth’s surface. But, still, the absorption of IR by CO2 is a very important component. And her observations - using the sun as the source of the infrared - is also a very relevant observation. This is because:

• Infrared light can carry heat energy from one hot body to another
• A large amount of the heat transfer from the sun to the earth comes in the form of infrared light
• CO2, which is present in the atmosphere in a significant amount, is a strong absorber of infrared light

So I don’t think her work is irrelevant. It is very relevant. But I do think that the title “Scientists understood physics of climate change” is stretched because this experiment by itself is not enough to describe all of the complexity of the green house effect and climate change.