Skip to content
  • Categories
  • Recent
  • Tags
  • All Topics
  • Popular
  • World
  • Users
  • Groups
Skins
  • Light
  • Brite
  • Cerulean
  • Cosmo
  • Flatly
  • Journal
  • Litera
  • Lumen
  • Lux
  • Materia
  • Minty
  • Morph
  • Pulse
  • Sandstone
  • Simplex
  • Sketchy
  • Spacelab
  • United
  • Yeti
  • Zephyr
  • Dark
  • Cyborg
  • Darkly
  • Quartz
  • Slate
  • Solar
  • Superhero
  • Vapor

  • Default (No Skin)
  • No Skin
Collapse
Caint logo. It's just text.
John Carlos BaezJ

johncarlosbaez@mathstodon.xyz

@johncarlosbaez@mathstodon.xyz
About
Posts
5
Topics
5
Shares
0
Groups
0
Followers
0
Following
0

View Original

Posts

Recent Best Controversial

  • Good news here in Scotland!
    John Carlos BaezJ John Carlos Baez

    Good news here in Scotland!

    "A grid-scale battery in the Scottish Highlands got a chance to prove its mettle in March when, 11 days after it started up, a massive wood-burning generator in Northern England shut down unexpectedly. Suddenly 1,877 megawatts of supply was missing, causing the 50-hertz frequency of the grid’s alternating current to crash below its 49.8-Hz operating limit in just 8 seconds.

    But the new 200-MW battery station leapt into action within milliseconds, releasing extra power to help arrest the frequency collapse and keep the grid running.

    Conventional fossil-fuel generators have historically helped thwart these kinds of problems. With the inertia of their spinning rotors, their kinetic energy provides a buffer against rapid swings in frequency and voltage. But the response in the Highlands was one of the world’s first examples of a grid-scale battery commissioned to do this kind of grid-stabilizing job.

    Without moving parts, the lithium battery storage site—the largest in Europe and located in Blackhillock, Scotland—simulates inertia using power electronics. And in an innovative twist, the battery site can also provide short-circuit current in response to a fault, just like conventional power generators.

    Four more of these battery sites are under construction in Scotland."

    The article goes on to explain a bit more about how these batteries work and why they're so important for the solar- and wind-powered future. (Amusing that it was unreliable *wood* power needing help this time.)

    https://spectrum.ieee.org/grid-scale-battery-scotland

    Uncategorized

  • If you don't have a subscription to the Wall Street Journal, you can read a free version of this essay here:https://archive.is/ADjdyThis quagmire is getting bigger.
    John Carlos BaezJ John Carlos Baez

    If you don't have a subscription to the Wall Street Journal, you can read a free version of this essay here:

    https://archive.is/ADjdy

    This quagmire is getting bigger. It's another part of what William Gibson recently called the Singularity of Stupid.

    Uncategorized

  • New unicode math symbol just dropped!
    John Carlos BaezJ John Carlos Baez

    New unicode math symbol just dropped!

    It means "equal apart from errors that could be, like, infinite". 🤪

    https://www.johndcook.com/blog/2025/09/10/new-symbols-in-unicode-17/

    Uncategorized

  • Neutrino masses are weird.
    John Carlos BaezJ John Carlos Baez

    Neutrino masses are weird. First we thought neutrinos were massless. Then we thought they had positive mass. Then some evidence pointed to an IMAGINARY mass, which was crazy. That went away as the data got better. Now some people say evidence from cosmology points to a NEGATIVE mass. But I think this is even more crazy.

    You may think Einstein said

    E = mc²

    but actually his theory, special relativity, says

    E² = m²c⁴ + p²c²

    where p is momentum. So you can measure energy and momentum and figure out the SQUARE of mass - not mass itself.

    You might think mass creates gravity, but actually it's energy and momentum that create gravity, and we use the above equation to figure out mass from those.... or really the mass SQUARED.

    If the mass squared is negative, you've got something with imaginary mass, which is called a tachyon. Tachyons are bad - take my word for it.

    But if the mass squared is positive, the mass itself could be positive or negative. And it doesn't really matter which, since in special relativity all that matters is mass squared!

    You might think we can figure out mass just by *weighing* something - that is, using gravity. But in general relativity, gravity interacts with energy and momentum. So those are what matter. We work out mass from the formula above... but actually, it only tells us mass squared.

    Some new experiments in cosmology are somewhat in conflict with each other, in ways that supposedly could be explained by neutrinos with negative mass. But I don't buy it.

    I could be confused. I'll think about it more....

    https://www.sciencenews.org/article/neutrino-mass-phenomenon-cosmology

    Uncategorized

  • It's like something out of science fiction.
    John Carlos BaezJ John Carlos Baez

    It's like something out of science fiction. In China, they've built a 35-meter plexiglass sphere 700 meters underground. It holds 20,000 tonnes of a strange liquid, surrounded by 43,200 photomultiplier tubes that can detect tiny flashes of light. It's deliberately built 50 kilometers from a nuclear reactor. It will start operation soon.

    The goal? To measure some numbers in a 3×3 matrix.

    It's called the Pontecorvo–Maki–Nakagawa–Sakata matrix. Unless we are seriously confused — which is always possible — this matrix controls the behavior of the 3 kinds of neutrinos. Neutrinos of the first kind are produced as a byproduct of nuclear fission. But they can turn into the other kinds as they shoot along. The rate at which they do is in part described by this matrix. (It also depends on the masses of the 3 neutrinos.)

    What's the use of this? Easy: one goal of any prosperous civilization has always been to better understand the universe. It's just a tiny part of the grand scheme. It usually comes well after the goal of eating lots of tasty foods, or watching people run around playing with spheres. But sometimes it has huge effects, and some of us find it very exciting.

    To see more on this amazing device, which should start running this fall, read on....

    (1/3)

    Uncategorized
  • Login

  • Don't have an account? Register

  • Login or register to search.
  • First post
    Last post
0
  • Categories
  • Recent
  • Tags
  • All Topics
  • Popular
  • World
  • Users
  • Groups