Nothing to do with MiB

The Kaye Effect

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Present in shear-thinning fluids — when pouring it into a reservoir, a jet of fluid will occasionally emerge.

There’s an especially neat part at the end where the fluid is used as a light guide.

Pink

‘Superman’ vision penetrates opaque glass

It’s not quite X-ray vision, but a way has been found to transmit simple images through opaque objects using ordinary light – and physicists have used the method to project an image through glass covered in thick paint.

By reverse engineering the scattering process, the team were able to reconstruct an image from the light that had passed through the opaque paint layer. That scattering is complex, but it’s also predictable: the same light wave will always be scattered in the same way.

ArXiv paper.

Is it Getting Crowded in Here?

Initial NIF experiments meet requirements for fusion ignition

The experiments, described in an article in today’s edition of Science Express, the online version of the journal Science, resulted in highly symmetrical compression of simulated fuel capsules – a requirement for NIF to achieve its goal of fusion ignition and energy gain when ignition experiments begin later this year.

The test shots proved NIF’s ability to deliver sufficient energy to the hohlraum to reach the radiation temperatures – more than 3 million degrees Centigrade – needed to create the intense bath of X-rays that compress the fuel capsule. When NIF scientists extrapolate the results of the initial experiments to higher-energy shots on full-sized hohlraums, “we feel we will be able to create the necessary hohlraum conditions to drive an implosion to ignition,” said Jeff Atherton, director of NIF experiments.

Of Cranks and Crackpots and Sealing Wax

How I found glaring errors in Einstein’s calculations

Or rather, I have not, but I know lots of people who have. For some time now, I have been an avid reader and collector of webpages created by crackpot physicists, those marginal self-styled scientists whose foundational, generally revolutionary work is sadly ignored by most established scientists. These are the great heroes, at least in their own eyes, of alternative science. In pre-Internet ages, these people routinely sent sheaves of notes and articles to established physicists and mathematicians, warning them that the papers contained proofs of Goldbach’s conjecture or Fermat’s theorem, or revolutionary models of gravitation and the atom. Scientists would just as routinely consign all this brilliant stuff to the wastepaper basket.

But then a miracle happened – CERN and DARPA created the Internet… and crackpots now all have their webpages! The whole world can benefit from exposure to alternative science.

Some interesting observations, including “The crackpot theory is based on textbooks,” i.e. crackpots tend to focus only on the “big examples” given in textbooks (e.g. Michelson-Morley for relativity)

As I said, crackpots are all committed to the principles of sound science – and they have done their homework. So where did it all go wrong? The textbook problem is in my view the crucial clue. Crackpots devote entire sites to discussing the Michelson-Morley experiment. To most physicists, such discussions are largely irrelevant, as these classic experiments were only the first ones in a long series of tests that showed the complete agreement between observations and predictions from special relativity. Also, the crackpots are generally not aware that every day, in thousands of labs all over the world, people are performing experiments that require special relativity, and that these experiments turn out all right because relativistic principles are included in people’s computations.

One thing this treatise ignores is the slice of psychoceramics that have no math skillz whatsoever. These are invariably in the “my theory is intuitive” crowd, and they post lots of pretty pictures about their helical, or möbius, or toroidal electrons, and how everything is really one particle — all you have to do is put another “twist” in the loop, or take it away, and you’ve got a proton or a photon. These are often folks who want to explain what energy is, or mass is, or some other metaphysical theme, rather than how things behave in nature, which is what scientists are after.

Update: in addition to Ian’s link in the comments, Bee just wrote something up on Backreaction. Division by Zero

Smoke but no Mirrors

Optical Trapping and the Momentum of Light

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The explanation talks about the wave-particle duality, but I think that’s a distraction. This is a dipole force phenomenon; the beam’s intensity is greatest at the center, and where the focal point occurs, as shown in the drawing at the end of the post. This gives rise to a gradient in the electric field. If you put a dielectric particle in this region, it will feel a force in the direction of the field maximum, or toward the highest intensity of light.

Say Hello to my Little Friend

My new sofa with recliner capability. It was delivered last week, in time for the playoff games this past weekend.

sofa

I did love my old sofa, but after 20 years of putting up with me the springs and frame were shot.

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