462 subscribers
478 photos
23 videos
36 files
941 links
Download Telegram
Forwarded from Авва
Молодой математик, выросший в Донецке и Киеве, учившийся и живший в Москве, покончил сегодня жизнь самоубийством после неудачной попытки покинуть территорию РФ. Это его прощальное письмо.

https://t.me/const_poems/101
🙏1
Forwarded from Life's Too Short
Yulia's Dream – безкоштовна науково-дослідницька програма з математики для обдарованих школярів (9-11 класів) з України🇺🇦

Програма присвячена пам’яті Юлії Здановської, 21-річної української студентки-математика, переможниці Європейської олімпіади з математики 2017 року, яка загинула від російської ракети у рідному місті Харкові.

Yulia's Dream – це ініціатива в рамках PRIMES – Програми досліджень у галузі математики, техніки та природничих наук для старшокласників Масачусетського технологічного інституту. За цією програмою учні збиратимуться онлайн раз на тиждень у невеликих групах, щоб вивчати розширені математичні теми за межами шкільної програми або працювати над математичними дослідницькими проєктами під керівництвом академічних наставників із числа аспірантів факультету математики Масачусетського технологічного інституту та спеціалістів з математики. Інструкція буде доступна українською, англійською та російською мовами.

Деталі 👉🏻math.mit.edu/research/highschool/primes/YuliasDream.php

MIT Department of Mathematics
Forwarded from Axis of Ordinary
"The Church-Turing thesis was born after Kleene got dosed with laughing gas!

Nobody knew how to use the lambda-calculus to define the "predecessor" function, which subtracts 1 from any natural number except 0, which it leaves alone. At the dentist, Kleene saw how to do it."

Source: https://twitter.com/johncarlosbaez/status/1505962963747758080
Forwarded from gerontion
Hearing is a fundamental sense of many animals, including all mammals, birds, some reptiles, amphibians, fish, and arthropods. The auditory organs of these animals are extremely diverse in anatomy after hundreds of millions of years of evolution, yet all are made up of cellular tissue and are morphologically part of the bodies of animals. Here, we show that hearing in the orb-weaving spider Larinioides sclopetarius is not constrained by the organism’s body but is extended through outsourcing hearing to its extended phenotype, the proteinaceous, self-manufactured orb web. We find that the wispy, wheel-shaped orb web acts as a hyperacute acoustic antenna to capture the sound-induced air particle movements that approach the maximum physical efficiency better than the acoustic responsivity of all previously known eardrums. By sensing the motion of web threads, the spider remotely detects and localizes the source of an incoming airborne acoustic wave, such as those emitted by approaching prey or predators. By outsourcing its acoustic sensors to its web, the spider is released from body size constraints and permits the araneid spider to increase its sound-sensitive surface area enormously, up to 10,000 times greater than the spider itself. The spider also enables the flexibility to functionally adjust and regularly regenerate its external "eardrum" according to its needs. The outsourcing and supersizing of auditory function in spiders provides unique features for studying extended and regenerative sensing and designing novel acoustic flow detectors for precise fluid dynamic measurement and manipulation.

https://www.pnas.org/doi/10.1073/pnas.2122789119
tag yourself
🔥4
Forwarded from Цуберок 🇺🇦 #УкрТґ
кажуть, що звичайна формула кінетичної енергії — лише наближення, яке працює при низьких швидкостях
Language of fungi derived from their electrical spiking activity

Abstract:

Fungi exhibit oscillations of extracellular electrical potential recorded via differential electrodes inserted into a substrate colonized by mycelium or directly into sporocarps. We analysed electrical activity of ghost fungi (Omphalotus nidiformis), Enoki fungi (Flammulina velutipes), split gill fungi (Schizophyllum commune) and caterpillar fungi (Cordyceps militaris). The spiking characteristics are species specific: a spike duration varies from 1 to 21 h and an amplitude from 0.03 to 2.1 mV. We found that spikes are often clustered into trains. Assuming that spikes of electrical activity are used by fungi to communicate and process information in mycelium networks, we group spikes into words and provide a linguistic and information complexity analysis of the fungal spiking activity. We demonstrate that distributions of fungal word lengths match that of human languages. We also construct algorithmic and Liz-Zempel complexity hierarchies of fungal sentences and show that species S. commune generate the most complex sentences.

https://royalsocietypublishing.org/doi/10.1098/rsos.211926
👍2