41:50 a small mistake, and prior to this a slightly misleading explanation of how thermal conditions in the sun's center (T=14 mln K) allow thermonuclear fusion of protons. I'll start with that. Coulomb repulsion barrier of 2 protons can be easily computed, thermal energy too (it is ~kT). Thermal energy is ~100 times too low to overcome the electrostatic potential. For a brief while in 1920s this was a major conundrum. Why the sun shines, and why it (thankfully) shines so inefficiently, releasing much less heat per second from 1 kg than a car battery, was figured out thanks to the idea of quantum tunneling by Georgiij Gamow, at the time quite fresh out of St. Petersburg university. (The reader may find it either amusing or terrifying that Gamow's authobiography "My world line" starts with a story of his grandfather, Novorossia priest and later Metropolit of Odessa cathedral, miraculously surviving an explosion of a British naval artillery shell in Sevastopol in 1855; in 2024 it is likewise is done with British long-range rockets Storm-shadow). If Omega * r = const., i.e. Period ~ r, as the lecturer says, and a star (R~0.7e6 km, P ~ 1 day) contracts until it reaches P~ 0.01 s, then the radius must shrink by a factor (1day)/0.01s = 0.8e7, i.e. the new radius must r = R/0.8e7 ~ 0.7e6 km /0.8e7 ~ 90 m. This is wrong by two orders of magnitude, and such a small stellar-mass object would be a black hole not a neutron star. I'll let the readers discover the error in this derivation. Have fun. A nice lecture overall. Pawel Artymowicz, UofT

Пока у нас преподают такие вот "преполы" можно просто говорить на все "бог так решил" ... Виртуальные фотоны .. четы Мляяяя несёшь 🤦🏼‍♀️ увольте его нахер

Как доступно ! О таких умозрительных вещах, как виртуальные фотоны! Браво!

Заряд электрона чей берем поТомсону?