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Fighter jet pilot demonstrates centripetal force, a concept that Isaac Newton discovered between 1676 and 1677. However, the concept of centripetal force was not actually discovered in a single event or by a single individual but rather evolved over time through the works of multiple scientists and thinkers. Here...

11,803,442 次观看 • 3 年前 •via X (Twitter)

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The fascinating concept of Non-Newtonian fluids, which transition from a liquid state to a solid-like state when pressure is applied, has a rich history that spans several centuries. The study and understanding of these peculiar fluids have evolved over time, leading to a wide range of practical applications and scientific insights. One of the earliest references to Non-Newtonian behavior in fluids dates back to the 17th century when Sir Isaac Newton formulated the basic principles of fluid mechanics. Newton's laws of fluid motion primarily applied to Newtonian fluids, which exhibit constant viscosity and flow behavior regardless of the applied force or pressure. However, it soon became apparent that not all fluids behaved in this predictable manner. In the mid-19th century, a scientist named Thomas Andrews made significant contributions to the understanding of Non-Newtonian fluids. Andrews conducted groundbreaking experiments with carbon dioxide, revealing that under high pressure, this gas could transform into a liquid. This observation marked one of the earliest instances of pressure-induced phase changes in fluids. The term "Non-Newtonian" itself was coined in the 20th century to describe fluids that did not adhere to Newton's classical laws of fluid dynamics. These fluids exhibited a variety of behaviors, but one of the most intriguing was their ability to solidify or increase in viscosity when subjected to stress or pressure. One of the most famous examples of such behavior is cornstarch mixed with water, which forms a substance known as "oobleck" that becomes more solid when pressure is applied. In the modern era, Non-Newtonian fluids have found applications in various fields, including food science, engineering, and material science. They are used in products like quicksand, body armor, and even in the development of impact-resistant materials. One of the key insights that emerged from the study of Non-Newtonian fluids is the importance of understanding the relationship between stress and strain, as well as the influence of time-dependent properties on their behavior. This knowledge has led to advancements in rheology, the study of flow and deformation in materials, and has practical implications in areas such as industrial processing, medicine, and the design of everyday products.

Historic Vids

2,632,483 次观看 • 2 年前

Meet the Xenobots, they are not machine, they are PROGRAMMABLE biological robots that can REPRODUCE. — The concept of xenobots has been a fascinating topic in the realm of developmental biology, and the latest findings have left me utterly astonished. These microscopic entities have been observed to not only self-assemble into complex forms but also exhibit a level of autonomy and adaptability that challenges our conventional understanding of multicellular organization. The researchers, led by Michael Levin, have successfully demonstrated that embryonic frog cells can spontaneously form into xenobots, which are capable of movement, self-organization, and even communication with one another. These xenobots are not merely passive aggregates of cells but rather dynamic systems that can adapt to their environment and respond to stimuli and be programmed to a degree. What's even more remarkable is that these xenobots have been found to be capable of reproduction. As Eva Jablonka, an evolutionary biologist, noted, "a xenobot may be induced to fragment and form two small ones," which raises the possibility of these entities undergoing a form of evolution. This has significant implications for our understanding of the origins of multicellularity and the evolution of complex life forms. The ability of xenobots to self-organize and adapt to their environment is thought to be mediated by a complex interplay of genetic and environmental factors. Levin suggests that the genome provides a set of rules and tendencies that allow cells to collectively "compute" their own solutions to growth and form, rather than being rigidly determined by a predetermined plan. The potential applications of this research are vast and varied, ranging from regenerative medicine to the development of novel biomaterials to a dystopian nightmare. However, what's most exciting is the prospect of gaining a deeper understanding of the fundamental principles that govern the emergence of complex life forms. As Levin notes, "we need a science of where larger-scale goals come from," and the study of xenobots may provide a key insight into this question. The discovery of xenobots and their remarkable properties has opened up a new frontier in the study of developmental biology and has significant implications for our understanding of the evolution of complex life forms.

Brian Roemmele

50,780 次观看 • 1 年前