In an instant, everyone had stayed at home for more than a month because of the epidemic. During this period, the glorious days when the great physicist Newton escaped the plague at home spread widely. So what did Newton do during this time? After my investigation, I have compiled such an article, so that people who are bored at home can learn more about Newton's situation at home. Maybe it will also greatly encourage you who are interested in physics, and also make great results. ~
Life at Trinity College
On June 3, 1661, Newton entered Trinity College, Cambridge's most famous college, as a publicly funded student (must work to earn money). Trinity College's courses mostly reflect Aristotleism in the fourth century, and Cambridge University at that time was not a knowledge center, which also caused Newton to ignore the standard courses taught at the university and have time and opportunities to read and think Various other issues are spent almost all of my spare time reading the works of contemporary philosophers.
During his studies, Newton used notes to record his readings and some of his thoughts on them, and some of them were entitled "Quaestiones quaedam Philosophicae", from which we can find that he had no doubt about Galileo, Thomas Hobbs (British politician, philosopher), Henry Moore (British philosopher, ethicist, theologian), Robert Boyle, Plato, and Aristotle are among the books written. The one that most interested Newton was Descartes—though Descartes' theory was not in the scope of the course at the time.
Interestingly, Newton's interest in philosophy soon turned to physics (though there was no definition of the subject at the time), and he soon discovered something that almost all previous philosophy did not cover, which was in his Notes on Descartes—especially those on Descartes' optical theory. Newton was deeply fascinated by light and vision, and he carried out many experiments one after another. Disregarding these experiments may make him lose sight (such as staring at the sun for as long as possible).
Around the end of 1663, Newton began to study mathematics-a course that was rarely taught in school. In 1664, he purchased a variety of cutting-edge books, including Francis van Schutten (Dutch mathematician), Descartes and Wallis (British mathematician, physicist) in geometry, algebra, and infinite series Work. During this time, Newton learned most of the mathematics knowledge at that time through self-study, and was very interested in pure mathematics and how to apply mathematics to life. During this time, Newton also left a famous saying that passed on to future generations:
"Plato is my friend, Aristotle is my friend, but my greatest friend is truth ."
However, at that time Newton had to solve an important problem, that is, if he wished to continue his studies, he must obtain a longer-term scholarship at Cambridge University-but in the previous three years, he was not in the regular course Outstanding. Fortunately, Newton eventually won a scholarship in April 1664 (this may be with the help of his patron Humphrey Babinton or the new Lucas mathematics professor Isaac Barrow) Which enabled him to study for another four years. The scholarship also allowed Newton a degree of financial freedom, and he became more obsessed with research, often not sleeping all night or eating during the day. In less than a year, however, he had to leave Cambridge—because of the Great Plague in England in 1665.
Woolthorpe Study Life
Newton left the school in the early summer of 1665. He returned to school in March 1666, but left in June due to the plague. He did not return until April 1667. During the two-year college suspension, Newton returned to his mother's home in Woolthorpe in the countryside. Fifty years later, he looks back on these years, and after explaining his work during this time, he adds:
"All of this happened during the two-year plague of 1665-66. During that time, I was in the heyday of my creative career and paid more attention to mathematics and philosophy than ever before. "
This record comes from Newton's "annus mirabilis."
Of course, this can also be regarded as a natural result of Newton's efforts. Woolthorpe's leisure environment allows Newton more freedom to pursue the work he wants to do. The obvious point is that during this period, Newton laid a lot of foundation for his future work, and even some work was not published until 30 years later. These efforts can be boiled down to three areas:
: Calculus-studying the mathematics of change is vital to understanding the world around us;
:gravity;
: Optics and Light Behavior.
In mathematical research, Newton listed 22 problems he wanted to study and divided them into five categories. He first studied the tangent (differential) of the curve and the integral of the curve. Through these "new analyses," he calculated the area enclosed by the hyperbola, and finally came up with a way to find the area enclosed by almost all known algebraic curves at the time. In the fall of 1665, he extended these ideas to see the area swept by the solution curve as the area swept by a moving point. He used the term "fluxionals" to describe the increase in area in this method, which marked the advent of modern calculus. And in it, he has regarded "speed" as a kind of flux, and defined it as an offset within an infinitesimal time interval.
He then discovered the relationship between integrals and differentials, and discovered the generalized binomial theorem in the process of summing several series—this was his first major discovery. In the same year, he also received a bachelor's degree.
In 1666, Newton reviewed these mathematical problems twice, and summarized the results of these studies into three papers: one written on November 13, 1665, entitled "to find ye velocities of objects bodys by ye lines the describe ", the remaining two were published in 1666, the previous one was entitled" To resolve problems by motion these following proposition are sufficient ", and finally An article containing a complete description of his calculus theory was written in October 1666.
Mathematics is not the only subject studied by Newton. In fact, he spends most of his time on issues of mechanics and optics.
In mechanical sciences, Descartes deals with collisions by analyzing the effects of internal forces (called "forces of object motion") on moving objects, while Newton advocates that "external forces acting on objects and changes in object motion have causality Relationship. At the same time, he realized that the momentum of two objects separated from each other remained unchanged, even if they collided with each other-this later became the principle of conservation of momentum. From this, Newton seems to have found the second law of motion. At this point, however, he was perplexed by the more complex problem of circular motion, and eventually Newton agreed with Descartes's view: that moving objects always strive to retreat from the middle-this obviously accords with Descartes's theory of moving objects. Has the inherent "centrifugal force" idea. Newton calculated the centrifugal force of a circularly moving object with a radius r and velocity v as F = mv ^ 2 / r-which reminded him of Galileo's "Dialogue Concerning the Two Chief World Systems). He used his results to show that the rotation of the earth does not throw objects into the air because gravity (measured by the speed at which objects fall) is greater than the centrifugal force generated by the rotation of the earth. He then continued to prove that if Kepler's third law is assumed to be correct (R is proportional to 2/3 of T), then this means that the centrifugal force (that is, gravity) must have a square power of F proportional to R One of the forms. Once again, he seems to be very close to discovering the law of gravity, but our idea underestimates the leap required to derive from a single result to the entire dynamic system-before Newton can formulate universal laws of kinematics, Several major advances must be made-so the law of gravity was not proposed until 30 years later.
Similarly, during Woolthorpe's days, Newton continued to try to study what he called "celebrated phaenomena of colours" (this was also one of the earliest beginnings of spectroscopy experiments), partly because of Robert Huke published "Micrographia" in 1665. Hook put forward a theory: the color is a mixture of light and dark, and the light is generated by "pulses". His color scale ranges from vivid red (considered to be pure white light with the least darkness added) To dark blue (considered to be completely obscured by darkness, the last step before being completely dark). Newton realized that this was not the case-when viewed from a distance, white paper with black characters on it did not show color, but was mixed with black and white, showing gray.
At the time, many researchers were experimenting with color using prisms, and their main idea was that prisms somehow colored white light, such as light from the sun. In these experiments, Descartes, Hook, and Boyle placed the screen close to the prism and saw the light passing through the prism appear as a mixture of multiple colors. In a study upstairs at the Woolthorpe house, Newton conducted an experiment: a light beam came in through a window, advanced 22 feet, passed through a prism, and projected a spectrum on a distant wall. White light is divided into different colors, and each color is bent by a different amount by the prism. He then used this system to carry out many experiments, the most critical of which he called the "Experimentum Crucis" experiment: placing a screen with a small slit on the way of the spectrum so that there was only one color Light (such as blue) passes through to illuminate the wall, and then he places a second prism on the path of blue light. The pure blue light has not changed, proving that the prism has not changed the color, so a critical Important conclusion: white light consists only of different colors mixed together, and prisms can only separate these colors. He recombined the different colors of light through three prisms to obtain white light, confirming this view.
None of the above can explain the color of the solid. Newton's efforts in this direction were less successful, because he mistakenly believed that all of these colors were caused by reflections-if an object looked blue, it was because it preferentially reflected blue light. Newton also studied a peculiar phenomenon discovered by Hooker, that if a curved glass is brought into contact with a flat glass sheet, a very thin ring will be seen around the contact point, which is also the "pulse" theory advocated by Hooker The main reason. Newton quantified the size of these rings (now called "Newton's rings") and knew the curvature of the curved glass to extract the length of the pulse, but he believed that these "pulses" were in the particulate medium that constituted the light Some kind of vibration disturbance, not really light, as Hook assumed. From here we can also see Newton's firm belief that light is made up of particles.
Follow-up: Return to Cambridge
After that, the plague ended, Newton returned to Cambridge in 1667, and his career began to flourish-he was elected as a junior researcher at Trinity College, a year later in 1668, and received a master's degree and was elected as a senior researcher. In 1669, the original Lucas mathematics professor Sack Barlow resigned, and Newton was appointed as a substitute, starting his brilliant discovery career ... Until 1689, Newton almost stayed at Cambridge University, doing many fields Known achievements in later generations ...
How's it been, after reading Newton's story, have you been greatly encouraged? If so, hurry up and learn at home! Maybe the next Newton is you