While Sean Carroll’s latest chat-from-home presentations on his YouTube channel address the “biggest ideas” in the universe, other theoretical physicists explore whether our mind-boggling big universe has sort of a shelf life. A final reservation date, so to speak, at a fantastically socially-distanced restaurant at the end of the universe. Reference: Forbes > “What Will… Continue reading A shelf life for the universe?
So, regarding interaction of matter, there’s a major inversion of perspective between classical physics and quantum field theory (QFT): hallmarked particles which create fields vs. excitations created (and destroyed) in ubiquitous extant fields. As Ethan Siegel said: … in quantum field theory, quantum fields aren’t generated by matter. Instead, what we interpret as “matter” is… Continue reading Equal footing in quantum physics
[Communicating science series] While we’re all doing stay-at-home, theoretical physicist Sean Carroll created a chat-from-home series on his YouTube channel. Usually each informal talk (so not lecture-like organization) has a followup Q&A video. The Biggest Ideas in the Universe is a series of videos where I talk informally about some of the fundamental concepts that… Continue reading Biggest ideas in the universe – Sean Carroll chats concepts
[Communicating science series] This is a concept often espoused by science popularizers over the decades. Even the background for plot vouchers in some sci-fi adventures. An amazing fact: We and everyday objects around us are mostly empty space! So, miniaturize matter. Fantastic Voyage! Honey, I Shrunk the Kids. Downsizing. That’s why superman could walk through… Continue reading Our friend the atom, mostly empty space?
[“Quantum foundations” series] Demons in physics? Well, historically as fanciful ways to explore theories using skilled marvels – an illuminating rather than malevolent context. Pure imagination, not imagineering, eh. Physicist James Clerk Maxwell created a thought experiment in 1867. His idea involved a fantastical “finite being” able to sort molecules of a gas. Rarified acuity… Continue reading Laplace’s demon RIP? – demons of physics
I read more articles this past week about research on the proton. Some refined measurements. Some better insights into topics in quantum theory. Rather than add comments to related posts, I decided that a new post was appropriate. It struck me that the proton, as a composite particle (“particle” in the sense of an excitation… Continue reading Proton soup – a turbulent, dynamically complicated structure
[Communicating science series] [Draft] Communicating science is more important that ever in this era. Elsewhere I’ve posted various visualizations, including Online Video, which convey physics concepts at different levels of difficulty. And I continue to seek better visualizations of quantum field theory, demonstrating the disconnect from our everyday experience while using metaphors which avoid (to… Continue reading Quantum physics myths – communicating science
Imagine a grain of fine beach sand. What’s its size? Classification scales vary, but let’s say less than a tenth (0.1) of a millmeter (mm). A grain of table salt. Same question. Maybe ~0.3 mm. In either grain there are a gazillion molecules. Now imagine something a thousand (1000) times smaller – a micrometer-sized grain.… Continue reading Tiny grains tell a stellar story
Ask people on the street “What are X-rays?” and you’ll likely get a variety of replies. About medical and dental X-rays. Stories about Superman’s X-ray vision. (Why does lead block X-rays?) Invisible particles that allow us to see through stuff. Technical explanations about electromagnetic radiation. So, street surveys typically reveal levels of understanding, which I’ll… Continue reading Levels of understanding – what are X-rays?
[“Quantum foundations” series] A physicist walks into a bar, and asks the bartender, “What time is it?” The bartender is about to reply but then recognizes the customer. “You’re a physicist, correct? So, it’s a trick question.” So, what’s with time? A venerable philosophical question. A foundational question in physics. We have electronic devices, extremely… Continue reading Whence the arrow of time?