Why can't you collimate incoherent light as well as a laser? Updated 2025-06-17 +Created 1970-01-01
You could put an LED in a cavity with a thin long hole but then, most rays, which are not aligned with the hole, will just bounce inside forever producing heat.
So you would have a very hot device, and very little efficiency on the light output. This heat might also behave like a black-body radiation source, so you would not have a single frequency.
The beauty of lasers is the laser cavity (two parallel mirrors around the medium) selects parallel motion preferentially, see e.g.: youtu.be/_JOchLyNO_w?t=832 from Video "How Lasers Work by Scientized (2017)"
Sometimes, these are more than just mechanics, but also have deeper life analogues. The title of Zen and the Art of Motorcycle Maintenance comes to mind. Sometimes they are just mechanics.
With more philosophical metaphors:
- when your bike breaks, that provides an unique opportunity to learn how to fix it: try to fix your own bike before taking it to the shop
- if the wind is blowing against you on the way out, it will likely blow behind you on the way back. But remember that the other way around also applies.
- always take one extra clothing layer than what you think you will need in your back pocket or sport bag, especially when time is changing fast in Sprint and Autumn. The weather on the road outside of town can change very quickly!
- if you took a turn, and it feels wrong, stop to check the map, and possibly backtrack to safety. When it feels wrong, it usually is a bad idea, e.g. roads where cars are too fast/too many. But if you take a wrong turn and it feels right, then follow it without fear and see what it leads to!
- don't carry a speedometer on your bike. Analysis can be done afterwards on Strava. The only measurement that matters is "how awesome am I feeling right now?". Live in the moment instead of checking your speedometer every 10 seconds.
- cycle when you body calls it out of addiction, not out a goal that you've made up that must be reached
With less philosophical metaphors:
- learn how much water and food you need to take for a trip. Otherwise, you will bonk at some time, when you least expect, it happens very suddenly.And then you better hope to God that you can find a food shop nearby. Luckily this was the case for Ciro's first and only bonk so far.And besides bonking all out, being tired and hungry makes you make stupid decision, especially where traffic is involved!Food is safety. Light is safety. Time is safety. Calm is safety. Chocolate bars and candy cannot count as lunch food, only delay lunch. A sandwich with ham cheese and salad is food. A bag of M&M's with a can of soda can bring you back from the dead.When you are not in familiar grounds, take twice as much as you think you might possibly ever need. Hofstadter's law.You will also learn that, surprise surprise, carbohydrates that you ate one or two days before a ride stay stored in your liver and muscles, and also greatly affect how quickly you will bonk, thus the concept of carbohydrate loading.
- correct saddle hight is fundamental, your legs must be almost fully stretched at the bottom position
- it is impossible to reach the correct tire pressure with (cheap?) hand pumps, their only purpose is to fill up a flat tire so you can get home after a long ride. But a track pump.
- clean and lube your chain. The speed benefit is instantaneous and mind blowing. It also greatly improves gear shifting.This also prevents the chain from rusting, because the lube takes up the place where water would stay, and the muck makes it harder for water to evaporate.This is the most common bike maintenance mistake you see on the streets: people with that high pitched overly dry chain noise.
- when a piece on your bike breaks and has no clear name written on it, you can try to identify it Google images
- the more you watch YouTube maintenance videos without haste, the more you end up learn random new stuff that unexpectedly saves you later
- if you took a turn, and it feels wrong, stop to check the map, and possibly backtrack to safety. When it feels wrong, it usually is a bad idea, e.g. roads where cars are too fast/too many
- public place with lots of people are bicycle parking Hell, because due to anonymity and the large number of distractions, it becomes exponentially more likely that someone will fuck you bike somehow, e.g. by dropping it on the ground. Always search a bit for a reasonable place to park, and avoid overcrowded parking spaces at all costs.
- gear change matters
- when you get on your bike to start riding, start riding slowly and gradually switch up pedal forces and gears. Things may have shifted in a weird position as it gets kicked around in parking. Ciro managed to bend his derailleur like that!
- spin to win, AKA learn to user your gears
- it is not shameful to ride on your lower gears on a hill. You can actually go surprisingly fast with them, and conserve energy for later. Learn when to use each gear ratio.
- learn to identify your suppliers:
- www.wiggle.co.uk/: in Europe, this is best place to buy clothing from, and also good for some bike parts. It is the most organized website, and contains non-generic shit which Amazon is full of.For bike parts Amazon is also worth looking into however. Bike parts a bit different from clothing because you have to make sure that stuff fits, so you hopefully know exactly the part name before before buying it, and therefore website organization is not as crucial.Wiggle is however guilty of shameless: discounts that happen more often than not
- always take your lights off the bike into your bag when you park, anywhere, and for any amount of time, even if a quick stop. Drug addicts are everywhere, always ready love to steal and resell them.
- sometimes you do something stupid like going into a really muddy path, and it is really fun, because you've never been there in your life. But then your bike gets really dirty, and your feet are wet and freezing, and you promise yourself you will never do something that stupid again. But then you do it again in a different location, because it was too much fun. Once more unto the breach just comes to Ciro's mind every such time. Embrace this.
Examples under vhdl.
Run all examples, which have assertions in them:
cd vhdl
./runFiles:
- Examples
- Basic
- vhdl/hello_world_tb.vhdl: hello world
- vhdl/min_tb.vhdl: min
- vhdl/assert_tb.vhdl: assert
- Lexer
- vhdl/comments_tb.vhdl: comments
- vhdl/case_insensitive_tb.vhdl: case insensitive
- vhdl/whitespace_tb.vhdl: whitespace
- vhdl/literals_tb.vhdl: literals
- Flow control
- vhdl/procedure_tb.vhdl: procedure
- vhdl/function_tb.vhdl: function
- vhdl/operators_tb.vhdl: operators
- Types
- vhdl/integer_types_tb.vhdl: integer types
- vhdl/array_tb.vhdl: array
- vhdl/record_tb.vhdl.bak: record. TODO fails with "GHDL Bug occurred" on GHDL 1.0.0
- vhdl/generic_tb.vhdl: generic
- vhdl/package_test_tb.vhdl: Packages
- vhdl/standard_package_tb.vhdl: standard package
- textio
* vhdl/write_tb.vhdl: write
* vhdl/read_tb.vhdl: read - vhdl/std_logic_tb.vhdl: std_logic
- vhdl/stop_delta_tb.vhdl:
--stop-delta
- Basic
- Applications
- Combinatoric
- vhdl/adder.vhdl: adder
- vhdl/sqrt8_tb.vhdl: sqrt8
- Sequential
- vhdl/clock_tb.vhdl: clock
- vhdl/counter.vhdl: counter
- Combinatoric
- Helpers
* vhdl/template_tb.vhdl: template
Gilberto is definitely the most psychedelic/tribal one of the The Holy Trinity of popular Brazilian music, though he also has a boyish quality to his soul.
He is also perhaps the one that impresses Ciro Santilli the most, at times he can't help but feel:
OMG how the hell did he come up with that?!
By GitHub around Black Lives Matter, due to a possible ludicrous relationship with slavery of black people:
For the love of God, the word "master" is much more general than black slavery. If you are going to ban it, you might as well ban the word "evil".
Amazing talk by Richard Feynman that describes his experiences at Los Alamos National Laboratory while developing the first nuclear weapons.
Transcript: calteches.library.caltech.edu/34/3/FeynmanLosAlamos.htm Also included full text into Surely You're Joking, Mr. Feynman.
- www.youtube.com/watch?v=uY-u1qyRM5w&t=2881s describes the computing aspects. Particularly interesting is the quote about how they used the typist secretary pool to emulate the IBM machines and debug their programs before the machines had arrived. This is exactly analogous to what is done in 2020 in the semiconductor industry, where slower models are used to estimate how future algorithms will run in future hardware.
Accounts:
- twitter.com/lukedashjr on Twitter. Status as of January 2024:This dude doesn't fuck around. Or perhaps he only fucks around. Either way.
father of 10 children
- www.linkedin.com/in/lukedashjr/ on LinkedIn
- bitcointalk.org/index.php?action=profile;u=3318 on bitcointalk.org
- www.reddit.com/user/luke-jr/
- github.com/sponsors/luke-jr
- freenode username:
luke-jr, mentioned e.g. at bitcointalk.org/index.php?topic=38007.0 from Section "Prayer wars"
Author of the prayer side of the Prayer wars.
Creator of Eligius pool Bitcoin mining pool.
According to LinkedIn he studied at the Benedictine College in Kansas.
TODO is his real birthname "Luke Dash Jr."?
Apparently he had his coins stolen in January 2023, then worth $3.5m: blog.cryptostars.is/luke-dashjr-an-original-bitcoin-developer-loses-all-his-btc-88421c395ce5p...
The bad:
- Clunky UI
- circuit diagram doesn't show any state??
April 2024: merged with some fraud protection thing, is it sill a Wiki? Unclear, seem sto have lost that aspect: twitter.com/judegomila/status/1783028847983956430
techcrunch.com/2019/04/30/golden-launch/Exactly! Deletionism on Wikipedia is so sad, and especially for companies. In particular e.g. Ciro Santilli tried to create a page for PsiQuantum, and it got reverted... and now golden has one of the largest Google hits for it: golden.com/wiki/PsiQuantum-PBDGXRA
Quote 1.
Golden wiki vs Deletionism on Wikipedia
. To state the obvious: Wikipedia is an incredibly useful website, but Gomila pointed out that notable companies and technologies like SV Angel, Benchling, Lisk and Urbit don’t currently have entries. Part of the problem is what he called Wikipedia’s “arbitrary notability threshold,” where pages are deleted for not being notable enough. (This is also what happened years ago to the Wikipedia page about yours truly — which I swear I didn’t write myself.)
TODO how do they do moderation?
As of April 2024Asked at: twitter.com/cirosantilli/status/1777250258235302233 Their last tweets were from August 2023, so maybe they just silently shutdown? Their name is too generic and hard to search for efficiently...
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They do have knowledge graph built-in which is cool.
Looking at the energy level of the Schrödinger equation solution for the hydrogen atom, you would guess that for multi-electron atoms that only the principal quantum number would matter, azimuthal quantum number getting filled randomly.
However, orbitals energies for large atoms don't increase in energy like those of hydrogen due to electron-electron interactions.
In particular, the following would not be naively expected:
This rule is only an approximation, there exist exceptions to the Madelung energy ordering rule.
His combination of politically incorrect dirt talk with amazing quirky decks captures Ciro's imagination.
Anonymous no face-reveal.
The videos are heavily edited with all pauses cut out, which makes them very quick to watch and saves viewer time.
Modern focused, with some occasional newer formats mixed in.
When Wizards publishes several useless sets in a row without a single modern playable card, he's just forced into Standard.
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