So, the short answer is yes. A useful model, at a certain scale. How can that be? The cosmos is full of stuff. Vast collections of stars, planets, rocks, dust, gas. Chunked over vast distances. Not what our everyday experience considers fluid stuff. Well, in physics and engineering, fluid dynamics embraces what typically are referred… Continue reading The cosmos is like a fluid?
So, what are axions? I’ve noticed more articles lately about axions. Why all the fuss, eh? • Wiki The axion is a hypothetical elementary particle postulated by the Peccei–Quinn theory in 1977 to resolve the strong CP problem [violation of the combined symmetries of charge conjugation and parity] in quantum chromodynamics (QCD). If axions exist… Continue reading What are axions – real or not?
In quantum physics, mathematically discontinuous changes – or jumps – between quantum states are popularly referred to as quantum leaps (remember the TV series). As to whether quantum leaps are instantaneous (zero time) or not – as well as random (without any harbinger) – is an open question in physics. This article below recaps additional… Continue reading Are quantum jumps instantaneous?
[“What’s changed in the last ~50 years” series] As noted elsewhere, this blog is sort of a personal journey, a way to explore topics in physics, and milestones and achievements in the field. Advances in quantum physics. Open areas of research. Unresolved questions. And, in particular, the theme of what’s changed in the last ~50… Continue reading Is supersymmetry dead?
NASA’s outreach efforts over the decades have touted the benefits of space science in our (macroscopic) everyday lives. Technology. How about quantum physics? A recent YouTube video by Sabine Hossenfelder (below) is a useful start in answering the question: How does our “big and warm” everyday experience evince quantum effects? (from transcript) … the weird… Continue reading Connecting everyday experience with quantum effects
This Quanta Magazine article (below) is a helpful visual recap of whether the cosmos is “flat” or not. Does the cosmic landscape of stars and galaxies extend / expand in all directions like an endless piece of paper? Or another “flat” geometry – “by cutting a chunk out of Euclidean space and gluing it together.”… Continue reading Does the universe have a shape?
An article from Quanta Magazine (below) recaps the history of space-time symmetries in physics and how those symmetries have, in a sense, been simplified: Galilean (Newtonian) static, separate space and time. Relativistic “flat” space-time – Minkowski / Poincaré / Einstein. de Sitter spherical space-time: “… in the same way that the finite speed of light… Continue reading Universal symmetries – what really is broken?
This post was inspired by Don Lincoln’s YouTube video “Subatomic Stories: Is the Planck length really the smallest?” In his Q&A (where he responds to questions from prior videos), he notes a caveat about the law of conservation of energy. Energy may not be conserved … because space-time can change. He offers some links for… Continue reading When conservation of energy goes out the window?
E = mc² The Holy Grail of modern physics is a so-called theory of everything, a unified field theory, a theory which unifies all known “forces.” That is, unifies all the fundamental interactions of nature. The three “quantum” interactions (electromagnetism, weak, strong) and gravitation. A conventional sequence of theories depicts final unification as occurring at… Continue reading Making matter from light – ultra energies and unification of forces
Paraphrasing: Just a note before you go,A vision to be learnedTraveling near the speed of lightIt’s easy to get … Imagining how things would look when traveling near the speed of light is an interesting exercise. Using a freeware video game developed by MIT Game Lab (2012), this visualization (below) by The Action Lab is… Continue reading Sightseeing near the speed of light – realistic simulation
