In the world of black holes, there are generally three size categories: stellar-mass black holes (about five to 50 times the mass of the sun), supermassive black holes (millions to billions of times the mass of the sun), and intermediate-mass black holes with masses somewhere in between.

While we know that intermediate-mass black holes should exist, little is known about their origins or characteristics—they are considered the rare "missing links" in black hole evolution.

The James Webb Space Telescope's deepest view of a single target yet depicts spinning arcs of light that are galaxies from the universe's distant past, the European Space Agency said Tuesday.

The new image took the world's most powerful telescope more than 120 hours to capture, making it the longest Webb has ever focused on a single target.

For the past decade, scientists have been trying to get to the bottom of what seemed like a major inconsistency in the universe. The universe expands over time, but how fast it's expanding has seemed to differ depending on whether you looked early in the universe's history or the present day. If true, this would have presented a major problem to the gold-standard model that represents our best understanding of the universe.

But thanks to the new James Webb Space Telescope, scientists from the University of Chicago have been able to take new and better data—suggesting there may be no conflict after all.

A team from MIT and the Woods Hole Oceanographic Institution (WHOI) has developed an image-analysis tool that cuts through the ocean's optical effects and generates images of underwater environments that look as if the water had been drained away, revealing an ocean scene's true colors. The team paired the color-correcting tool with a computational model that converts images of a scene into a three-dimensional underwater "world," that can then be explored virtually.

The researchers have dubbed the new tool SeaSplat, in reference to both its underwater application and a method known as 3D Gaussian splatting (3DGS), which takes images of a scene and stitches them together to generate a complete, three-dimensional representation that can be viewed in detail, from any perspective.

For now, the method requires hefty computing resources in the form of a desktop computer that would be too bulky to carry aboard an underwater robot. Still, SeaSplat could work for tethered operations, where a vehicle, tied to a ship, can explore and take images that can be sent up to a ship's computer.

From this paper:

Data points indicate best performers by year of market introduction.

The magnified plot shows progress in cool white LEDs from 1996 to 2020. For comparison, efficacies of best performers in legacy lighting technologies for 2020 are shown as coloured horizontal lines.

Note the logarithmic scale of the vertical axis on the main plot and the linear scale on the magnified plot.

From this article:

most improvements in the energy efficiency of LEDs were driven by research and development efforts. Surprisingly, however, R&D contributed relatively little to reductions in the cost of the devices, which were instead linked to economies of scale and continuous manufacturing process improvements over time.

Although the theory is promising, the duo point out that they have not yet completed its proof. The theory uses a technical procedure known as renormalization, a mathematical way of dealing with infinities that show up in the calculations.

So far Partanen and Tulkki have shown that this works up to a certain point—for so-called 'first order' terms—but they need to make sure the infinities can be eliminated throughout the entire calculation.

"If renormalization doesn't work for higher order terms, you'll get infinite results. So it's vital to show that this renormalization continues to work," explains Tulkki. "We still have to make a complete proof, but we believe it's very likely we'll succeed."

Why is the spring strengthened in the middle?

It doesn't seem to affect the spring's buckling characteristics.

My speculation is that it's to reduce spring noise. That strengthened region at the middle is where the spring will buckle outwards most, resting against the barely visible side rails on the inside of the case. Instead of just one wobbly contact point it now has three rigid ones as a "skate" to reduce the stick-slip noise when opening and retracting the tip. Is this right?

(The pen is a Mitsubishi Uni-Ball Power Tank, pretty much my favorite model.)

Tesla Cybertruck appears to be facing significant sales challenges. After initial hype faded, and over a million reservations turned out to be as real as unicorns, Tesla is now enabling leasing options and free upgrades to move its inventory of the futuristic pickup truck. The company's recent silence on the Cybertruck, even omitting it from their earnings call, speaks volumes about the situation.

Tesla initially projected sales of 500,000 Cybertrucks annually and established production capacity at the Giga Texas for 250,000 units per year. After working through the initial reservation backlog with fewer than 40,000 deliveries, the automaker is now struggling to sell the remaining vehicles.

I thought this was a very insightful video. Anders is often able to discern stark simple truths and their implications without falling into the trap of common misconceptions.

The prediction about what Russia will do on January 20th seems very likely to me.

Anders was one of the very few analysts that predicted Russia was going to invade in the months/weeks before their actual invasion.

Imagine you were reborn as a female queen ant with an expected lifespan of about 15 years (worker ants live about half a queen's timespan), and had the ambition to make the most of your tiny new life. And you got to keep your current intellectual capacity and knowledge.

How much could you achieve as an ant?