[Draft] [RIP series] So, this recent SciTechDaily article (below) about the “Singularity Problem” caught my attention today. Because it’s a reminder of what the much fictionalized / mythologized notion is really about. The need for a deeper understanding of nature. The representational limits (approximate character) of mathematical models. A theory’s domain of applicability.  As… Continue reading Singularities RIP?
[Draft] If space-time is considered as a kind of material, then what properties make sense? Properties that can be observed, measured. In the context of General relativity, (aggregate) properties related to curvature and rippling. Like elasticity, stiffness. In the context of quantum physics, (discrete) properties related to quanta, energy density, charge, spin, entanglement. Like gradients,… Continue reading How stiff is space-time?
Yes, Virginia, there is a black hole in the center of our Milky Way . What might be expected if you asked, à la a Jay Leno “Jaywalking” segment, some random people this question: “Where’s the nearest black hole?” Well, tallying those that know what a black hole is  … those that know what… Continue reading Yes, Virginia, there is a black hole in the center of our Milky Way
[“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?
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
This Space.com article “Solar Eclipse Science Helps Prove Einstein’s Relativity Theory in Nat Geo’s ‘Genius’” published on May 30, 2017, reminded me of the connection between the study of solar eclipses and Einstein’s theory of general relativity. While the U.S. prepares for the Great American Total Solar Eclipse coming on Aug. 21, National Geographic’s “Genius” recounts… Continue reading Solar eclipse and relativity — there is no Vulcan
One of the major sources of confusion I’ve encountered in reading about modern physics is the discussion of gravity. No surprise, eh. Classical mechanics includes both Newtonian and relativistic mechanics. In Newtonian physics, gravity is an attractive force, which acts at a distance between all objects; and can be represented as a universal gravitational field.… Continue reading GR: Chicken or egg redux