An unhurried sense of time is in itself a form of wealth. ~Bonnie Friedman
1814 – Julius Robert von Mayer, German physician and physicist is born.
Julius Robert von Mayer was a German physician and physicist and one of the founders of thermodynamics. He is best known for enunciating in 1841 one of the original statements of the conservation of energy or what is now known as one of the first versions of the first law of thermodynamics, namely that “energy can be neither created nor destroyed”. In 1842, Mayer described the vital chemical process now referred to as oxidation as the primary source of energy for any living creature. His achievements were overlooked and priority for the discovery of the mechanical equivalent of heat was attributed to James Joule in the following year. He also proposed that plants convert light into chemical energy.
1844 – Karl Benz, German engineer and businessman, founded Mercedes-Benz is born.
Karl Friedrich Benz was a German engine designer and car engineer, generally regarded as the inventor of the first automobile powered by an internal combustion engine, and together with Bertha Benz, pioneering founder of the automobile manufacturer Mercedes-Benz. Other German contemporaries, Gottlieb Daimler and Wilhelm Maybach working as partners, also worked on similar types of inventions, without knowledge of the work of the other, but Benz received a patent for his work first, and, subsequently patented all the processes that made the internal combustion engine feasible for use in an automobile. In 1879, his first engine patent was granted to him, and in 1886, Benz was granted a patent for his first automobile.
1915 – Albert Einstein presents the field equations of general relativity to the Prussian Academy of Sciences.
General relativity is a theory of gravitation that was developed by Albert Einstein between 1907 and 1915. According to general relativity, the observed gravitational effect between masses results from their warping of spacetime.
By the beginning of the 20th century, Newton’s law of universal gravitation had been accepted for more than two hundred years as a valid description of the gravitational force between masses. In Newton’s model, gravity is the result of an attractive force between massive objects. Although even Newton was troubled by the unknown nature of that force, the basic framework was extremely successful at describing motion.
Experiments and observations show that Einstein’s description of gravitation accounts for several effects that are unexplained by Newton’s law, such as minute anomalies in the orbits of Mercury and other planets. General relativity also predicts novel effects of gravity, such as gravitational waves, gravitational lensing and an effect of gravity on time known as gravitational time dilation. Many of these predictions have been confirmed by experiment, while others are the subject of ongoing research. For example, although there is indirect evidence for gravitational waves, direct evidence of their existence is still being sought by several teams of scientists in experiments such as the LIGO and GEO 600 projects.
General relativity has developed into an essential tool in modern astrophysics. It provides the foundation for the current understanding of black holes, regions of space where the gravitational effect is so strong that even light cannot escape. Their strong gravity is thought to be responsible for the intense radiation emitted by certain types of astronomical objects (such as active galactic nuclei or microquasars). General relativity is also part of the framework of the standard Big Bang model of cosmology.
Although general relativity is not the only relativistic theory of gravity, it is the simplest such theory that is consistent with the experimental data. Nevertheless, a number of open questions remain, the most fundamental of which is how general relativity can be reconciled with the laws of quantum physics to produce a complete and self-consistent theory of quantum gravity.
1947 – Red Scare: The “Hollywood Ten” are blacklisted by Hollywood movie studios.
The Hollywood blacklist—as the broader entertainment industry blacklist is generally known—was the mid-20th-century practice of denying employment to screenwriters, actors, directors, musicians, and other U.S. entertainment professionals because of their suspected political beliefs or associations. Artists were barred from work on the basis of their alleged membership in or sympathy with the American Communist Party, involvement in progressive political causes that enforcers of the blacklist associated with communism, and refusal to assist investigations into Communist Party activities. Even during the period of its strictest enforcement, the late 1940s through the late 1950s, the blacklist was rarely made explicit or verifiable, but it directly damaged the careers of scores of individuals working in the film industry.
The first systematic Hollywood blacklist was instituted on November 25, 1947, the day after ten writers and directors were cited for contempt of Congress for refusing to testify to the House Committee on Un-American Activities. A group of studio executives, acting under the aegis of the Motion Picture Association of America, fired the artists—the so-called Hollywood Ten—and made what has become known as the Waldorf Statement.
Back in 2012 Adafruit got their 200,000th order! Today, Adafruit is at 600,000 and counting!
Today is a big milestone for Adafruit, we just passed our 200,000th order (2012-11-25 05:17:12). Stephan from Germany is the 200,000th order – We’ve given him his order for free and a $200 gift certificate. This was his first order at Adafruit for some Raspberry Pi related products, he was pleasantly surprised by the news 🙂
Thank you everyone for supporting Adafruit all these years, we’re looking forward to serving you for the next 200,000 orders and beyond.
This day last year we started taking Bitcoin as a payment method!
Greetings programs! Adafruit is pleased to offer BitCoin as a payment method for Adafruit purchases. We soft-launched over the weekend and had tons of happy customers, we’re using BitPay as our payment processor. BitPay is an electronic payment processing system for the bitcoin currency. BitPay enables online merchants to accept bitcoins, as a form of payment like payments from Visa, Mastercard, Amex, Google Wallet and Paypal.
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