General · Language

QFT – How many fields are there?

[“Building a ‘verse” series] Ever since I started reading about Quantum Field Theory (QFT), I was interested in how physicists talk about fields. And the multiplicity of fields. And how quantum fields compare to classical fields. So, as I’ve written elsewhere, the basic notion is that every matter particle is an excitation (or localized vibration)… Continue reading QFT – How many fields are there?

General · Language

Atomic tweezers — levitated optomechanics

[Topic placeholder] I’ve been following articles for awhile about micron, nanometer, and atomic level confinement and manipulation. The development of “optical tweezers” facilitated exploration of biological particles with sizes in the micrometer and nanometer range such as viruses and bacteria and subcellular components. Optical traps also facilitated exploring properties of trapped individual molecules and atoms.… Continue reading Atomic tweezers — levitated optomechanics

Language · Media

Ergosphere – what?

Regarding recent posts about black holes, here’s another YouTube video by The Science Asylum on the topic (published February 16, 2019): “Black Holes can SPIN?!?” I’ve previously highlighted The Science Asylum as a science communicator. This latest video is an interesting overview of black holes: non-spinning vs. spinning, the math vs. reality inside and outside… Continue reading Ergosphere – what?

General · Language · Media

Cosmological fact and fiction

In the last few months, I’ve been struck by how many articles have been published in the popular media and science news about black holes and the Big Bang. Mainstream physics and science communications (like phys.org, quantamagazine.org, etc) lately seem to be discussing more and more “mind blowing” geometries of the universe (or multiverse, eh).… Continue reading Cosmological fact and fiction

General · Language

A photon’s frame of spacetime — no rest for the massless

I’ve thought about this question for years. A FAQ. Imagine you’re traveling at the speed of light. Well, physics says that’s impossible. Mass’ gotcha. So, what can travel at the speed of light? Photons (not just the visible ones). So, imagine … does a photon “experience” space and time? Some weeks ago I recall reading… Continue reading A photon’s frame of spacetime — no rest for the massless

General · Language · Media · Site

Imaging a light pulse?

Reference: The 2018-2019 Watson Lecture Series, Caltech, Beckman Auditorium World’s Deepest-Penetration and Fastest Optical Cameras by Lihong Wang Wednesday, November 28, 2018, 8:00 PM – 9:30 PM Lihong Wang will discuss the development of photoacoustic tomography, which allows scientists to peer deep into biological tissue. He will also talk about his lab’s development of compressed ultrafast… Continue reading Imaging a light pulse?

Diagram · General · Language · Media

Communicating what physics says — Domain of Science YouTube channel

Today’s post is somewhat different than usual. I’m highlighting a YouTube channel. Communicating science to a general audience has a long history. The bibliography for my physics blog contains some books by authors to this purpose. Modern physics has many great stories, and the just plain strangeness of quantum physics lends itself to great storytelling.… Continue reading Communicating what physics says — Domain of Science YouTube channel

General · Language · Media

Acceleration causes gravity, gravity causes acceleration

As I’ve written elsewhere,  I sometimes think that generations of scientists raised in space might help advance physics, having lived in a world dominated by inertia (rather than friction). Especially in regard to a visceral understanding of microgravity. Like characters in the TV series The Expanse. So, this Space.com article (June 18, 2018) “Relativity: The… Continue reading Acceleration causes gravity, gravity causes acceleration

General · Language · Media

Multiverse paradox — potpourri of universes

I’ve been following this topic for years. Just some notes before I post something more complete — prompted by Stephen Hawking’s final research paper, much in the news. Multiverse: infinite or countable verses? • Prof Stephen Hawking’s multiverse finale (May 2, 2018), BBC News, includes a video. The study was submitted to the Journal of High-Energy… Continue reading Multiverse paradox — potpourri of universes