What happens when your magnetic compass starts spinning in the wilderness? Meet William Austin Burt, who took that as a cue to invent something new.
Special thanks to the Marquette Regional History Center for access to their library and solar compass exhibit!
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The Vikings were renowned navigators at a time before magnetic compasses were invented. So how’d they manage it? Their secret may have been these pretty-pointed crystals of calcite called Iceland spar, and this month’s SciShow Rocks Box subscribers will get to try this out for themselves!
‘Polycycle Illumination’ is a collection of tabletop lamps that reflect how a jellyfish pulsates and swims through the water.
Polyethylene is the most common plastic in the world. Used for food packaging, grocery bags, detergent bottles, and so much more, the often single-use items are ubiquitous in our daily lives.
For computational designer Xuanhao Li, polyethylene became a fruitful source for envisioning a new way to repurpose the omnipresent material.
While working as a textile developer, Li noticed that the plastic films lining boxes and wrapping textiles during transit were often thrown in the trash. He began to collect the material and experiment with its properties, particularly its transparency, malleability, and smooth texture, as it passed through a heat-press machine. “The aim was to fuse polyethylene films into sheets that balanced rigidity and flexibility while achieving a hazy translucency for lampshades,” he tells Colossal. “No material is inherently unattractive or cheap.”
When Li watched a documentary about sea turtles that mistook plastic bags for jellyfish, the explorations found their form. “The haunting imagery of drifting plastic and its tragic impact on marine life deeply moved me,” the designer shares. He also visited the Georgia Aquarium in Atlanta to observe the live animals and their bulbous bodies.
After developing the material, Li created digital motifs that imitated both a knitted structure and the jellyfish form, which he cut using a CNC machine. He adds:
I attached tentacles with varying widths, following rhythmic patterns that abstractly echo the textures of jellyfish tissue…For the top portion of the jellyfish, I employed a smooth, overlapping layering technique, which mimicked the delicate, rounded bell of the jellyfish. For the base, I used an opposing technique, where the pieces were knitted with the edges facing each other, resulting in a ridged texture that evoked the intricate, flowing form of jellyfish tentacles.
Resulting is Polycycle Illumination, an elegant collection of tabletop lamps. Standing at different heights, the designs together reflect the changes in shape as a jellyfish pulsates and swims through the water. Li hopes the series functions as both a functional object and a call to reduce plastic waste that threatens marine life. […]
We finally did the walking visit of the Cathedral I have always promised you guys. It’s hard to capture the unique beauty of this place. Please don’t watch this seeking information other than just two people hanging out and admiring the structures.
How to lead a happier, healthier and longer life. Check out our sponsor: https://betterhelp.com/veritasium to get matched with a professional therapist who will listen and help.
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A huge thanks to Prof. Robert Waldinger for all his help with this video.
To learn more about what makes for a good life, visit: https://the-good-life-book.com/ and • Robert Waldinger: What makes a good l…
A special thanks to Prof. Julianne Holt-Lunstad for her expert advice on the importance of social connections and the detrimental effects of loneliness and social isolation.
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Additional Videos:
Family Reacts to Winning CA$1 Million Lotto, NowThisNews via YouTube – https://ve42.co/CA1Lottery
Surgeon General discusses health risks of loneliness and steps to help connect with others, PBS NewsHour via YouTube – https://ve42.co/PBS-SG
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References:
Waldinger, R., & Schulz, M. (2023). The Good Life: Lessons from the World’s Longest Scientific Study of Happiness. Simon and Schuster.
Lindqvist et al. (2020). Long-run effects of lottery wealth on psychological well-being. The Review of Economic Studies. – https://ve42.co/Lindqvist2020
Wen et al. (2011). Minimum amount of physical activity for reduced mortality and extended life expectancy: a prospective cohort study. The lancet. – https://ve42.co/Wen2011
Nocon et al. (2008). Association of physical activity with all-cause and cardiovascular mortality: a systematic review and meta-analysis. European Journal of Preventive Cardiology. – https://ve42.co/Nocon2008
Blondell et al. (2014). Does physical activity prevent cognitive decline and dementia?: A systematic review and meta-analysis of longitudinal studies. BMC public health. – https://ve42.co/Blondell2014
Office of the Surgeon General. (2023). Our Epidemic of Loneliness and Isolation: The US Surgeon General’s Advisory on the Healing Effects of Social Connection and Community. – https://ve42.co/LonelinessEpidemic
Holt-Lunstad et al. (2010). Social relationships and mortality risk: a meta-analytic review. PLoS medicine. – https://ve42.co/Holt-Lunstad2010
Valtorta et al. (2016). Loneliness and social isolation as risk factors for coronary heart disease and stroke: systematic review and meta-analysis of longitudinal observational studies. Heart. – https://ve42.co/Valtorta2016
Shovestul et al. (2020). Risk factors for loneliness: The high relative importance of age versus other factors. PloS one. – https://ve42.co/Shovestul2020
Donovan et al. (2017). Loneliness, depression and cognitive function in older US adults. International journal of geriatric psychiatry. – https://ve42.co/Donovan2017
Lara et al. (2019). Does loneliness contribute to mild cognitive impairment and dementia? A systematic review and meta-analysis of longitudinal studies. Ageing research reviews. – https://ve42.co/Lara2019
Holt-Lunstad et al. (2015). Loneliness and social isolation as risk factors for mortality: a meta-analytic review. Perspectives on psychological science. – https://ve42.co/Holt-Lunstad2015
McIntyre et al. (2015). Compulsive Internet use and relations between social connectedness, and introversion. Computers in Human Behavior. – https://ve42.co/McIntyre2015
Kahneman & Deaton. (2010). High income improves evaluation of life but not emotional well-being. Proceedings of the national academy of sciences. – https://ve42.co/Kahneman2010
Killingsworth. (2021). Experienced well-being rises with income, even above $75,000 per year. Proceedings of the National Academy of Sciences. – https://ve42.co/Killingsworth2021
Killingsworth et al. (2023). Income and emotional well-being: A conflict resolved. Proceedings of the National Academy of Sciences. – https://ve42.co/Killingsworth2023
Photo: Ikiwaner (via Wikimedia Commons, GNU Free Documentation License)
Of the entire animal kingdom, perhaps elephants most mirror the human grieving process.
Many animals have been proven to express some form of grief. From Tanzania, Jane Goodall once recorded a young chimpanzee that died of grief following the death of his mother only weeks earlier. One study followed a beluga whale that carried her deceased calf for almost a full week, while another found lemurs giving “lost” calls in the presence of a killed family member. Out of all these, however, perhaps elephants resemble a human’s mourning patterns most closely.
Elephants are often considered one of the world’s smartest animals, so it naturally follows that they also experience such complex emotions and sensations as grief. They have been documented stroking the bones of the deceased, guarding carcasses, burying dead calves, and even crying. Though ignoring the remains or bones of other species, elephants almost always react to those of their own.
One poignant example of this is the death of Eleanor, the matriarch of a Kenyan elephant family called the First Ladies. Researchers noted that she was bruised, dragging her trunk along the ground, and, soon after, she collapsed. Grace, a matriarch from another family, then approached Eleanor, attempting to nudge her back on her feet. Eleanor once again thudded to the ground, and Grace became incredibly agitated, vocalizing, pushing, and refusing to leave her.
When Eleanor died the next day, another female named Maui attended to the body, rocking over and prodding at it. For a whole week, elephants from five different families visited Eleanor’s corpse.
Another account details how a researcher once hid a speaker in a thicket. The device played a recording of an elephant who had recently passed, which caused its family members to call out in distress. In vain, they attempted to search for the dead elephant, and its daughter called for days afterward. The experiment was never repeated by the researcher again. […]
24 Dec 2024
The inscribed square/rectangle problem, solved using Möbius strips and Klein bottles.
Playlist with more neat proofs: • Puzzles with beautiful solutions
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The on-screen argument for why all closed non-orientable surfaces must intersect themselves in 3d is a slight variation on one I heard from Dan Asimov.
Timestamps:
0:00 – Inscribed squares
1:00 – Preface to the second edition
3:04 – The main surface
10:47 – The secret surface
16:45 – Klein bottles
22:38 – Why are squares harder?
25:10 – What is topology?
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