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The mediocre teacher tells. The good teacher explains. The superior teacher demonstrates. The great teacher inspires. ’ A teacher has the power to transform souls and touch someone’s life in a positive way. It is one of the noblest of professions that deal with life-changing and destiny-altering powers. The teacher has the present as raw material on which she will finally carve and design the future … the children. It’s an ever evolving yet challenging and lifelong learning environment of which we are an integral part. Teaching is a chance to touch someone’s life in a positive way. Teachers are the pillars of society for they educate and mould the future citizens of a country. Teaching, like any other activity, emerges from ones inwardness. Motivating and exciting students is the key. Passion for teaching is innate. At the core of caring relationships are positive and high expectations that not only structure and guide behaviours, but also challenge students to perform what they believ...

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Two roads diverged in a wood, and I— I took the one less traveled by, And that has made all the difference. —Robert Frost, 1916 In his poem “The Road Not Taken,” Robert Frost famously wrote about choices. For graduate students in physics, the most familiar road is the academic path, but many other career paths are available to PhD physicists—far more than Frost’s two roads. According to NSF’s Survey of Doctorate Recipients, almost half of the 130 000 PhD physical scientists living and working in the US in 2017 were employed in the private sector, about 40% were employed in academia, and 9% worked in government settings In this article we examine the different career paths of PhD physicists working in private industry, academia, and government, and we describe what physicists in different sectors find rewarding about their chosen careers. In the first-ever 10-year follow-up survey of physics PhD recipients, the Statistical Research Center at the American Institute of Physics (AIP), whic...

Physics is an exploratory science. New experiments in physics change or expand our existing knowledge in one way or another. Let us find out how this has happened in history. 10. Galileo's Tower of Pisa experiment Before Galileo, a majority of people used to follow the teachings of ancient Greek philosopher, Aristotle, who had proclaimed that different weights when dropped from same height experienced different amounts of attraction from the Earth thus falling at different speeds. It is said that in 1589 Galileo climbed atop Tower of Pisa and dropped two objects of different masses in order to debunk Aristotelian belief. In 1971, astronaut David Scott re-created Galileo's famous experiment on the moon by dropping a hammer and a feather simultaneously. 9. Faraday's law of induction A sudden movement of a magnet through a coil produces a reading on the galvanometer meaning that a changing magnetic field can induce an electric current in the coil. This observation was first ma...

The mathematical physicist Freeman Dyson was famed for his visionary ideas that stretched far beyond pure science. Hamish Johnston looks at the life of a scientist who was never afraid to speak his mind The British-born mathematical physicist and public intellectual Freeman Dyson, who died on 28 February 2020 at the age of 96, was one of the most celebrated figures in 20th-century physics. He had spent most of his professional life at the Institute for Advanced Study (IAS) in Princeton, New Jersey, where he was a professor emeritus and remained active until his final few days. Dyson died at a hospital near Princeton, due to complications from a fall, according to his son, the science historian George Dyson. Dyson began his career in the 1940s, making important contributions to the development of quantum electrodynamics (QED) . Early on, however, he broadened his interests to include nuclear reactors, space travel, climate and biology – both on Earth and elsewhere in the cosmos. Dyson a...

Just as physics is not a list of facts about the world, history is not a list of names and dates. It is a way of thinking that can be powerful and illuminating   Some things about physics aren’t well covered in a physics education. Those are the messy, rough edges that make everything difficult: dealing with people, singly or in groups; misunderstandings; rivals and even allies who won’t fall in line. Physicists often do not see such issues as contributing to science itself. But social interactions really do influence what scientists produce. Often physicists learn that lesson the hard way. Instead, they could equip themselves for the actual collaborative world, not the idealized solitary one that has never existed. History can help. An entire academic discipline—history of science—studies the rough edges. We historians of science see ourselves as illustrating the power of stories. How a community tells its history changes the way it thinks about itself. A historical perspective on...

A couple of weeks back I posted an answer to a question from a Twitter follower’s child, who asked “How Strong Is Space?” That was fun, so here’s another kid-question answered, this one from my own eight-year-old who goes by “The Pip” for Internet purposes. The other night, he asked “Why can’t atoms touch each other?” I’m not sure the exact reason why he asked this, but the phrasing suggests it’s related to the observation that there’s almost always some microscopic empty space between things that appear to be touching on a macroscopic scale. Possibly it’s even connected to the “Atoms are mostly empty space” idea that Ethan talked about recently. The short and simple version of the answer is that it’s not really correct to think of atoms as solid objects like little balls that can be forced into physical contact with one another. Most of the “size” of an atom is just the electron cloud that surrounds the nucleus, and that’s not a solid thing— it will shift around in response to electri...

I greatly enjoyed David Kaiser’s How the Hippies Saved Physics (here’s my review from 2011), so when I ran across a mention of this new book with “Quantum” in the title, I immediately sought out a copy. This sort of thing is highly relevant to my interests. Kaiser is a professor at MIT with a joint appointment in both physics and history of science, and as you would expect this collection of essays splits time between those two fields. The book contains a handful of pieces relating to Kaiser’s work in physics, chiefly about a “cosmological” test of quantum physics, using light from distant quasars as a random number generator for a Bell’s Inequality test (I talked briefly about this idea in the context of football in 2015). There are also a larger number of pieces primarily about the historical and social context of physics, mostly in the mid-to-late 20th century. Almost all of these were previously published (I think there’s only one that doesn’t have a “A version of this previously.....

As someone who derives significant income from writing for money, I end up spending a fair bit of time reading writing advice. Not because I'm in need of tips, myself-- after many years of this, I've got a routine that mostly works for me. Rather, I'm looking for good advice to pass on to other people, because I get asked for advice on a regular basis, and I don't really have much of my own to offer. That's how I came to read this advice post from Alyx Dellamonica, making an analogy between figuring out how fiction works and trying to learn about cars from a junkyard. I like the junkyard analogy quite a bit, but along the way she makes a couple of passing mentions to physics that I absolutely hate. Here's the first: With the arts, you not a physics professor laying out a formula, some cut-and-dried procedure for which there is one satisfactory answer. You’re not showing someone how to paint the perfect yellow line down the middle of a strip of road, or fly an ai...

Scattering Amplitude  Spinless Particle  we are dealing with quantum description of scattering.  Elastic Scattering $ \rightarrow $ between two spinless, non-relativistic particles of masses m1 and m2. During the scattering process, the particles interact with one another. If the interaction is time independent, we can describe the two-particle system with stationary states.  \begin{equation}\Psi\left(\vec{r}_{1}, \vec{r}_{2}, t\right)=\psi\left(\vec{r}_{1}, \vec{r}_{2}\right) e^{-i E_{T} t / n}\end{equation}  $ E_T $ is total energy.  \begin{equation}\left[-\frac{\hbar^{2}}{2 m_{1}} \vec{\nabla}_{1}^{2}-\frac{\hbar^{2}}{2 m_{2}} \vec{\nabla}_{2}^{2}+\hat{V}\left(\vec{r}_{1}, \vec{r}_{2}\right)\right] \psi\left(\vec{r}_{1}, \vec{r}_{2}\right)=E_{T} \psi\left(\vec{r}_{1}, \vec{r}_{2}\right) \end{equation}     defining $ ...