Mastodawn

Les capsules du prof Lutz Jul 30, 2024

#collapse ? It's not your fault. The wrong choices were made 10 millennia ago...

“Agriculture led to settlements, then possessions, surplus, armies to protect (and raid) surplus, property rights, patriarchy and monotheism, division of labor, hierarchy, classes, and subjugation of animals and humans. Many negative ecological impacts also accompanied agriculture such as deforestation, soil erosion, salt accumulation, desertification, among others.”

https://dothemath.ucsd.edu/2024/07/mm-9-recipe-for-disaster/

#DoTheMaths

MM #9: Recipe for Disaster | Do the Math

Show thread

💡𝚂𝗆𝖺𝗋𝗍𝗆𝖺𝗇 𝙰𝗉𝗉𝗌📱Nov 20, 2023

1/7
Last week for #MathsMonday we showed that Terms are separated by any operators, not just + and -, contrary to the impression one might get from this #Maths textbook. This week we'll again #DoTheMaths but on binary and unary #Math operators, and deduce for ourselves the #Mathematics properties of them. As far as I'm aware, they don't have a name, so I'm gonna call them TorAnds - the group of an operator and associated operand(s) 🙂

First note what the textbook says about an invisible + ...

Show thread

💡𝚂𝗆𝖺𝗋𝗍𝗆𝖺𝗇 𝙰𝗉𝗉𝗌📱Nov 13, 2023

3/5
Now let's look at where a textbook has been (perhaps unintentionally) misleading. It says "Terms are separated by + and - signs", which MAY lead one to think (and I've seen this claimed) that Terms are NOT separated by multiply and divide, only plus and minus. Indeed, above that it says "A Term is a collection of numbers, letters, and brackets, all multiplied/divided together" which further gives that impression. But is that even true? Well, let's #DoTheMaths 🙂 ...

Green💚🌻Molly Apr 22, 2023

This is why @TheGreenParty has been arguing for Universal Credit to be increased by £40 per week

RT to tell Sunak to #DoTheMaths
RT @jrf_uk: 🧮 We've done our #maths & it doesn't add up!

The current basic rate of #UniversalCredit falls £35 *per week* short of the actual cost of essentials like food, utilities & vital household goods

👉Join us in calling on the Govt to guarantee #OurEssentials https://t.co/W96obGGWaB

🐦🔗: https://n.respublicae.eu/GreenPartyMolly/status/1648222635799576578

Guarantee our essentials - The Trussell Trust

We’re calling on the UK Government to make sure the basic rate of Universal Credit at least covers life’s essentials.

The Trussell Trust

Doc Edward Morbius ⭕Sep 29, 2021

Solar Power: Abundant or not?

So, yes, "as much raw incident sunlight falls on the Earth in 1 hour as all of humanity uses in 1 year."

Sounds like a lot. About a 7,000-times surplus.

But when you start doing the maths, it turns out that 1) the amount of usable sunlight is far, far lower (about 100 -- 200x present human energy usage) and 2) baked-in assumptions of human energy consumption growth based just on population growth and a modest levelling-up for the global poor chews up about 1/5 of that surplus.

More depressing truth/reality here:

https://joindiaspora.com/posts/f9899b600300013a2eb4002590d8e506

And no, the message isn't that renewables aren't realistic. It's that our expectations aren't.

#energy #solar #solarPower #DoTheMaths #population #affluence #renewables #limits #LimitsToGrowth

Switching to Renewables: How much energy is available?

Switching to Renewables: How much energy is available? A reasonably good explainer on the potential for powering humanity on solar power: It's interesting and better information than I'd feared, though it still omits a lot, mostly in terms of baked-in assumptions of energ consumpion increases from future wealth and population increases. An apparently-large solar energy surplus rapidly diminishes within just the next century. https://www.youtube.com/watch?v=IZEaYjo4ZJU Basic facts: Global energy consumption is about 400 quadrillion BTU (quad), or 10,000 million tonnes of oil equivalent (mtoe), or 115 petawatt hours (PWh -- 115 million GWh) equivalent. Those are units, and they're big. The important thing is to look at the total amounts and what they translate to on a per-person basis. US consumption is about 100 quad, / 2,500 mtoe. Total incident raw solar power is about 7,000 times human energy use. That's what "as much solar energy falls on the entire Earth in 1 hours as huma...