The Geometry of Causality
Why Hacker News recommends it
Used as a go-to reference for relativity arguments, such as spacetime intervals being the same for all observers, and as a suggested follow-up for physics fans.
What it is
PBS Space Time explains how spacetime geometry and light cones determine the order of events and what can cause what. It visualizes causality in special relativity.
Recommended by 2 HN commenters across 2 different months, 2017 to 2022.
What Hacker News said
Recommends neom · 2017-02 · on “Theories about a link between the human mind and quantum physics”
I spend pretty much every weekend watching (super dyslexic) hours and hours of "stuff" about quantum, form quantum biology to physics to astro, here are some good ones around humans and the universe. Some may not seem totally relevant but give foundational knowledge, suggest watching in order: - [LINK] - [this video] - [LINK] - [LINK] - [LINK] - [LINK] - [LINK] - [LINK]
Recommends shagie · 2022-08 · on ““I survived the TCP transition” (2013)”
As an aside, the PBS space time video The Speed of Light is NOT About Light : [LINK] As an aside to the aside - as I rewatch it I quickly notice how young he looks (and then note the date is 2015 on there - one of the early ones and the production is less refined). You may also like The Geometry of Causality [this video]
Cites Rainymood · 2017-02 · on “Theories about a link between the human mind and quantum physics”
Good post, I made it a bit more legible Are Space and Time An Illusion? | Space Time | PBS Digital Studios [LINK] The Geometry of Causality | Space Time [this video] The Quantum Experiment that Broke Reality | Space Time | PBS Digital Studios [LINK] Quantum Biology: An Introduction [LINK] Quantum Biology: The Hidden Nature of Nature [LINK] Consciousness: Explored and Explained [LINK] The Mind After Midnight: Where Do You Go When You Go to Sleep? [LINK] Rebooting the Cosmos: Is the Universe the Ultimate Computer? [LINK]
Cites stcredzero · 2018-12 · on ““Diagram of All Space and Time” by Carl Sagan (1960s?)”
PBS Space Time on the same subject: [this video] Minute Physics SpaceTime Globe (The best tool for understanding relativity I've ever seen.) [LINK]
Cites stcredzero · 2018-12 · on “Discovered: The Most-Distant Solar System Object Ever Observed”
But why do intelligent people want to believe that any such coherent stories can actually be told in real life? We all know it's impossible. Even basic questions such as "How old are you" become unanswerable. Really intelligent informed people know the relative scales involved. So if all of Star Wars were re-imagined to occur using reasonable tech within the several cubic light years around Alpha Centauri, no speeds where severe relativistic time dilation effects are necessary for normal transportation. "How old are you" is readily answerable +/- a month for just about everyone, even most spacefarers. Heck, even the prequel trilogy makes more sense. (As Plinkett puts it, why are people on th
Cites stcredzero · 2018-12 · on “Discovered: The Most-Distant Solar System Object Ever Observed”
> If there's anything the universe is, it's Eventually Consistent. Please disregard this inconsistency guff! The Universe isn't Eventually Consistent. It's simply consistent. What's really going on, is that some programmers don't understand relativity. Relativity doesn't actually say that everyone gets their own reality. There is a consistent consensual reality. Spacetime intervals are consistent between all observers. The time ordering of events changes depending on the observer's POV and relative motion, but there is an underlying consistent reality that's the same for everybody. [LINK] [this video] The "Spacetime Globe" by Minute Physics is the most helpful thing I've seen, flat out, for under