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[Video] Missiles barrage hits Tel Aviv in c/worldnews@lemmy.ml
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Direct Air Capture vs Thermodynamics (Cool Worlds) [25:12] (piped.video)
 

Video Description:

Direct Air Capture (DAC) has been getting more and more attention over the last few years. Could we avert climate change by pulling carbon dioxide out of the atmosphere? Could we not just stop, but actually reverse the damage done? Unfortunately, most don't fully appreciate just quite how much CO2 we've emitted and the outrageous scale of the problem facing us. Today, we apply the fundamental principles of thermodynamics to question whether this is even feasible.

Written & presented by Prof. David Kipping. Edited by Jorge Casas. Fact checking by Alexandra Masegian.

Channel Description:

Space, astronomy, exoplanets, astroengineering and the search for extraterrestrial life & intelligence.

The Cool Worlds Lab, based at the Department of Astronomy, Columbia University, is a team of astronomers seeking to discover and understand alien worlds, particularly those where temperatures are cool enough for life, led by Professor David Kipping.

CHAPTERS (and key bits)

  • 0:00 Climate Change: Some CC is needed just to maintain a level.
  • 2:44 Removal Requirements: We released 37 Gt of CO2 in 2022.
  • 3:38 Possible Solutions: Trees are good for 4 years, then no space.
  • 5:03 Introducing DAC: IPCC estimates 20 Gt/yr @ 2050 required.
  • 5:43 Climate Anxiety: This video is sponsored by betterhelp.
  • 7:12 DAC Principles: Currently 19 DAC plants remove 10'000 tCO2/yr, or 0.000003% of global emissions.
  • 8:14 Scalability: Why this video focuses on physics, not economics
  • 9:29 Thermodynamics: Why DAC is a fight against entropy, introducing Gibbs. Lower limit: 120 kWh/tCO2
  • 12:08 Progressive DAC: Starting in 2025, remove how much and how fast?
  • 13:32 RCPs: Why 2.6 is discarded, why 4.5 is chosen (with an outlook on 8.5)
  • 15:09 Simulations: For 450 ppm, we need to scrub 20 GtCO2 in 2050. For 350, almost 80 Gt.
  • 17:03 Energy Requirements: 450 ppm requires 5% of global electricity. 350: 15%.
  • 19:34 Efficiency: Above numbers assumed 100% efficiency. Current estimate 5%, measured 8%.
  • 21:21 Conclusions: It's tough to do, but just possible. Easiest way: Stop emitting.
  • 24:35 Outro and credits
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An Explanation of Boltzmann Brains (Kurzgesagt – In a Nutshell) [10:15] (piped.video)
 

Absolutely everything you think about yourself and the universe could be an illusion. As far as you know, you are real and exist in a universe that was born 14 billion years ago and that gave rise to galaxies, stars, the Earth, and finally you. Except, maybe not.

Other explanations for Boltzmann Brains did not require an 'inside-out black hole', for example https://en.wikipedia.org/wiki/Boltzmann_brain, so this inclusion came as a surprise to me. Not sure if it's necessary.

What baffles me about the theory: If it's true, and reality is (mostly, statistically speaking) imagined ... the physical reality could be anything. It could be very different from the reality we live in. But we created our models of the universe in this one reality we know, and the theory of Boltzmann Brains emerged from that.

So based on these physical models we arrive at the idea of BBs. But if this idea is true, the physical reality could be completely different.

Or what do you think?

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NASA's Plan to Build A Telescope on the Moon | Real Engineering [15:05] (piped.video)
 

cross-posted from: https://lemm.ee/post/8135104

Honorable mention: The video was posted to https://lemmy.world/c/mealtimevideos 4 days ago: https://lemmy.world/post/4942489. I did not want to use the YouTube link as the primary link, hence reposting instead of cross-posting.

Further reading about the Lunar Crater Radio Telescope (LCRT):

They want to build the telescope on the far side of the Moon, to shield it from terrestrial (man-made) radiation. Is this premise in peril by other Moon missions? For example, do NASA or other space agencies have plans to build other bases on the far side of the moon, which could emit radiowaves which affect the LCRT?

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The Insane Ways Traffic Engineers Try to Make Streets "Safe" For Walking (CityNerd) (piped.video)
 

RRFBs. HAWK signals. Do any of these devices actually do what they're supposed to do, and how do traffic engineers decide when and where to install them?

As a European, much of this was mind-boggling to me. While I believe all of this is real, I still found myself wondering throughout the video: Is this actually the norm in the US, or are these some cherry-picked bad examples? It felt for me like a whole other level of systemic hostility.

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AES: How to Design Secure Encryption (Spanning Tree) (piped.video)
 

cross-posted from: https://lemm.ee/post/5467810

In 1997, a contest began to develop a new encryption algorithm to become the Advanced Encryption Standard. After years of debate, one algorithm was chosen as the AES. But how does AES work? And what makes for a secure encryption algorithm?

Spanning Tree is an educational video series about computer science and mathematics. See more at https://spanningtree.me

To be notified when a new video is released, sign up for the Spanning Tree mailing list at https://spanningtree.substack.com/

Spanning Tree is created by Brian Yu. https://brianyu.me/

Email me at brian@spanningtree.me to suggest a future topic.

  • 0:00 The Contest
  • 1:02 Encryption
  • 3:57 Confusion and Diffusion
  • 5:44 Block Cipher
  • 6:55 KeyExpansion
  • 7:34 AddRoundKey
  • 8:14 Substitution Cipher
  • 8:55 SubBytes
  • 11:30 MixColumns
  • 12:53 ShiftRows
  • 13:21 The Algorithm

Aug 22, 2023

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The beauty of collective intelligence, explained by a developmental biologist | Michael Levin (Big Think) (piped.video)
submitted 3 years ago by to c/psychology@lemmy.ml
comment fedilink
 

cross-posted from: https://lemm.ee/post/5320372

The strange science experiment that blew a worm’s head off… and blew our minds.

This interview is an episode from /channel/UCz7Gx6wLCiPw3F-AmXUvH8w, our publication about ideas that inspire a life well-lived, created with the /channel/UCMJ6QeJUbCUuhOSYZadF7sA.

Michael Levin, a developmental biologist at Tufts University, challenges conventional notions of intelligence, arguing that it is inherently collective rather than individual.

Levin explains that we are collections of cells, with each cell possessing competencies developed from their evolution from unicellular organisms. This forms a multi-scale competency architecture, where each level, from cells to tissues to organs, is solving problems within their unique spaces.

Levin emphasizes that properly recognizing intelligence, which spans different scales of existence, is vital for understanding life's complexities. And this perspective suggests a radical shift in understanding ourselves and the world around us, acknowledging the cognitive abilities present at every level of our existence.

Read the video transcript ► https://bigthink.com/the-well/intelligence-can-cells-think/?utm_source=youtube&utm_medium=video&utm_campaign=youtube_description

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Every Construction Machine Explained in 15 Minutes (Practical Engineering) (piped.video)
 

cross-posted from: https://lemm.ee/post/4411464

A very quick overview of nearly every machine you'll see on a construction site.

It takes a lot of big tools to build the roads, dams, sewage lift stations, and every other part of the constructed environment. To me, there’s almost nothing more fun than watching something get built, and that’s made all the better when you know what all those machines do.

The video admits in the end that the title is clickbait ("Every"). There are too many to be exhaustive.