How Special Relativity Makes Magnets Work on HackerTube: recommended by 7 Hacker News commenters across 7 separate months, 2014–2024.
explainer · evergreen
Veritasium explains magnetism as a consequence of special relativity. Length contraction of moving charges makes a current in a wire attract or repel a nearby moving charge.
HN commenters recommend it as a short, clear explanation of why moving charges create magnetic fields.
“if you are curious why a moving charge creates a magnetic field watch this Veritasium video”
8 Hacker News comments link this video. Each one links back to its thread.
I think what GP meant is that (from one viewpoint) magnetism is an emergent property of the electric field and relativity. Here is a simple explanation: ▶ this video
in “NASA Discovers a Long-Sought Global Electric Field on Earth” · View on HN
Sort of, electricity and magnetism are two sides of the same coin, electromagnetism, so it's waves in the electromagnetic field with the wire acting as a wave guide. (as far as I understand) Veritasium has a video that goes over this. It was pretty controversial at release but it gives a good overview. [link] And why magnets work due to relativity ▶ this video
in “Why does current flow the opposite way from the electrons?” · View on HN
Wow, this is the first time I have understood why nothing can go faster than the speed of light and why time dilation is a thing. A very easy to read article, give it a try. Also if you are curious why a moving charge creates a magnetic field watch this Veritasium video: ▶ this video
in “Why can’t I go faster than the speed of light?” · View on HN
Magnetism is a side effect of special relativity: moving charges have length contraction (depending on frame of reference) which makes them appear more/less dense and therefore an attractive/repulsive force. Veritasium on YouTube made a much better explanation: ▶ this video
in “Bohr–van Leeuwen theorem – magnetism in solids is a quantum mechanical effect” · View on HN
Here's a video explainer: ▶ this video Magnetism affects moving charges, but not stationary charges. A magnetic field in your reference frame is really just an electric field in the moving charge's reference frame.
in “Why is Maxwell's theory so hard to understand? (2007) [pdf]” · View on HN
That's right. Here is a pretty good video explaining magnetism as a relativistic effect of electrostatics - ▶ this video
in “Ultimate Electronics” · View on HN
Here some modern explanation of the phenomena: (I love the way they explain it) "How Special Relativity Makes Magnets Work" ▶ this video .
in “How Magnets Produce Electricity (1954) [video]” · View on HN
Another fun fact: Magnetic fields are a consequence of relativity and length contraction of electric fields. [link] This video also talks about it: ▶ this video
in “Is Aluminum Magnetic? (2013)” · View on HN