Wenn ChatGPT das Mathe-Paper schreibt 😅 (eigentlich gar kein lustiges Paper: www.ams.org/journals/not...)

Hours of daylight throughout the year in the Northern Hemisphere.

The entirety of Roy Kerr's paper solving the Einstein equations for a spinning black hole in case anyone wondered what it looks like. In terms of impact per line this paper has to be one of the all-time top 10.

I just got word that the faculty senate of my university is now dissolved and no longer exists, in compliance with the new Texas law. Yikes! I thought my university would somehow find a loophole, or an exemption, but it's official. It's a sad day for shared governance and checks and balances.

Along these lines, I googled my own book to find reviews and the AI Overview caught my eye. Literally half of what it said about my book is not in my book at all. If it gets it so wrong for a subject I know about, it's probably getting it so wrong on everything!

Oh cool! A video that I helped make is now up to 10 million views.

I made this chart for a class I teach, showing various electric charge setups. I think that it shows the pattern well. An arbitrary charge configuration can be represented as a combination of these, and often the higher-order multipoles can be approximated to be zero. #ITeachPhysics

There are various meiosis errors that can occur. In the error shown here, since Turner syn. girls rarely survive to birth, there is a greater chance of giving birth to a boy. When you take all errors into account and average, it's unlikely that the girl-boy ration at birth will be exactly 50%-50%.

It bugs me when people call it AI "hallucinations," because this puts the focus on the AI as if it is an innocent victim of a medical condition. The real problem is that people using the AI are fed false info. Better terms would therefore be: • AI lies • AI fabrications • AI invented falsehoods

Fresnel lenses are fun to play with if you ever get a chance. As shown in the picture, a Fresnel lens is made by dividing it into sections and removing unneeded material from each section, leading to a thin lens. You get a lens which seems unusually powerful for its size. #ITeachPhysics

A good friend of mine learned this the hard way and ended up in the hospital after taking herbal pills containing licorice root for several weeks (supposedly as an energy booster). Herbal pills aren't automatically safe just because they are marketed as natural!

Excessive consumption of genuine licorice (that hasn't been deglycyrrhizinated) causes dangerously high blood pressure and related problems because of a well-understood cascade of processes in the body. It can be found in licorice candy and herbal supplements that contain licorice root.

Saying that air is an electrical insulator oversimplifies the matter. Even at low voltages, air can indeed carry an electrical current, but you don't see it and the current is weak. This is why statically charged objects eventually end up uncharged. Their charge flows out into the air #ITeachPhysics

To be clear, this does not mean that everyone on this list was native German, Austrian, or Italian. Rather, before Hitler, Germany was the center of mass of physics research. The top minds from around the world came to Germany to get an education and do research, but then had to flee.

I've been reading about the history of physics and have been amazed by how many contributors to physics fled Nazi Germany, Nazi Austria, and Fascist Italy. I had fun making this table to get all the info into one place. #ITeachPhysics

I've been reading about the history of physics and have been amazed by how many contributors to physics fled Nazi Germany, Nazi Austria, and Fascist Italy. I had fun making this table to get all the info into one place. #ITeachPhysics

Years ago I worked as a scientist with a Top Secret security clearance at a national intelligence research lab. I can tell you that sharing highly classified information over a non-secure commercial phone app does not happen by accident. To do this, you have to go out of your way and... 1/2

Years ago I worked as a scientist with a Top Secret security clearance at a national intelligence research lab. I can tell you that sharing highly classified information over a non-secure commercial phone app does not happen by accident. To do this, you have to go out of your way and... 1/2

When you look at a transparent object, in some sense you are not looking directly at the object itself! Rather, you're looking at images of the background and surrounding objects after having been distorted by refracting through and reflecting off of the object.

It's now up to 7 million views.

This turned out better than I expected. Happy Pi Day!

Cool! I provided scientific consulting for this YouTube video (my name is in the credits), and it already has over three million views, a day after being released. It's a tricky concept to explain, but I tried my best to steer the writers in the right direction. www.youtube.com/watch?v=qJZ1...

Although the rigorous mixing of gases that occurs in the atmosphere below 90 km makes the atmosphere mostly homogeneous, so that its composition is independent of height, the gases do partially separate out according to mass above 90 km, as caused by gravity.

A redshift means a shift to lower frequencies, even if some frequencies are lower than red. A blue shift means a shift to higher frequencies even if some frequencies are higher than blue. But what about a violetshift? This phrase isn't used, but if it was, it'd mean the same thing as blueshift.

Every process that releases energy from a system involves the conversion of mass to the released energy. It's not just nuclear reactions. This fact is fundamental to the way that mass and energy behave. But this fact isn't useful outside of physics 'cause the changes in mass are tiny. #ITeachPhysics

team, is there anything more cursed than writing the date for a greek themed movie using roman numerals in american date order?

Human vision uses 20+ visual cues to see depth despite capturing 2D images on the retinas. One of these is the texture gradient cue, shown on the right. I was careful to make it so that no other depth cues are present (except a bit of recess shading). The left image is without this cue present.

1 in 5 US adults have experienced mental illness in the last twelve months. I'll bet he has no idea that many productive people around him who seem normal are dealing with or have dealt with mental illness recently.

Using the Laplace equation, you can solve analytically for the electric field strength near a statically charged conical tip or pit. I've plotted the results here. The field is very strong very close to a very sharp tip. This is why lightning rods are spikes. #ITeachPhysics

Using the Laplace equation, you can solve analytically for the electric field strength near a statically charged conical tip or pit. I've plotted the results here. The field is very strong very close to a very sharp tip. This is why lightning rods are spikes. #ITeachPhysics

When looking at a sphere, less than half of the sphere is within view. The closer you are, the less of it that you can see. This is why you need lots of satellites to provide full coverage to the earth.

The spikes you see coming out of stars in telescopic images mostly arise from the diffraction of light as it flows past the support arms that hold the secondary mirror in place. Diffraction is well understood, so which kind of support arms leads to which pattern is predictable. (I made this pic)

In real life, the planets of our solar system never literally line up along a single line in space, as shown in diagrams like the one below. The planets travel in tree-dimensional space along orbits that are not all perfectly aligned.

Some people get scared away from taking medications because of a long list of potential side effects on the packaging or documents, but *everything* has potential side effects, even drinking water. A risk-benefit analysis done with medical professionals is the best way to decide about taking meds.

This is a beautiful. I love lucky imaging in astronomy. It's the kind of approach that seems so simple and effective (in principle) that when you hear about it for the first time, you wonder why you hadn't already thought of it or already heard about it.

I recently switched to always using DuckDuckGo for web searches instead of Google Search, for boycott reasons, and I pleasantly discovered that DuckDuckGo doesn't force feed you AI junk as the first item. That's reason enough to make the switch!

💫🎉 Behind every successful ESA space mission, there's a woman. Behind the ESA & NASA Solar Orbiter mission, there are more than a hundred of them! Join us in celebrating them today, on international day of women and girls in science! #WomenInScience #WomenInSTEM 🔭🧪 www.esa.int/ESA_Multimed...

#NASAWebb’s sunshield plays a vital role in protecting the telescope from light from the Sun, Earth, and Moon, which could overheat the mirror and its scientific instruments. Credit: NASA, ESA, CSA, STScI. 🔭 🧪

During evaporation of water, there are water molecules from the air hitting and sticking to the surface and becoming liquid, in addition to water molecules from the liquid shooting off into the air. The evaporation rate therefore depends on the air's relative humidity.

"Infrared radiation" does not mean the same things as "thermal radiation." Infrared radiation is any radiation with a wavelength between mircowave and visible light, regardless of how it's created, while thermal radiation is any radiation created by thermal emission, regardless of wavelength.

"Infrared radiation" does not mean the same things as "thermal radiation." Infrared radiation is any radiation with a wavelength between mircowave and visible light, regardless of how it's created, while thermal radiation is any radiation created by thermal emission, regardless of wavelength.