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According to Planck and Einstein, E = hf. Where does your "n" come from? An electron moving at constant velocity does not emit emr.
The formula E = n * h * f comes from the concept of quantization of energy, a cornerstone of quantum mechanics.Here's the breakdown: * Planck's Hypothesis: In 1900, Max Planck proposed that energy is not emitted or absorbed continuously, but rather in discrete packets called quanta. These quanta of energy are now known as photons. * Planck's Constant: To describe this quantization, Planck introduced a fundamental constant, 'h', now known as Planck's constant. It has a value of approximately 6.626 x 10^-34 joule-seconds (J⋅s). * Energy of a Single Photon: Planck hypothesized that the energy (E) of a single photon is directly proportional to its frequency (f). Mathematically, this relationship is expressed as: * E = h * f * Multiple Photons: If you have 'n' number of photons, the total energy (E) would be: * E = n * h * fIn simpler terms:Imagine light as a stream of tiny energy packets. Each packet's energy is determined by its frequency (how fast it oscillates). Planck's constant (h) is a conversion factor that relates the frequency of the light to the energy of each packet.Key Points: * This equation revolutionized our understanding of light and laid the foundation for quantum mechanics. * It has numerous applications, from explaining the photoelectric effect to understanding the behavior of atoms and molecules.
* Multiple Photons: If you have 'n' number of photons, the total energy (E) would be: * E = n * h * f
Quote from: hamdani yusuf on 22/01/2025 12:10:13 * Multiple Photons: If you have 'n' number of photons, the total energy (E) would be: * E = n * h * fOnly if they all have the same energy. Misleading crap from Gemini as usual.
An electron moving at constant velocity does not emit emr.
Indeed there is. But as the electrons are moving very slowly, you'd have a job to detect it.
What's the frequency ?
Quote from: hamdani yusuf on 17/02/2025 07:37:03What's the frequency ?E = hf. You can work out the change in kinetic energy for yourself, knowing the drift speed of the electrons.
It is often said that quantum mechanics was discovered when classical physics predicted a curve that disagreed violently with the experiment, a phenomenon called U.V Catastrophe. Unfortunately, the story is a myth- closer to fairytale than truth. The real journey of Max Planck is a little messier but also a lot more interesting. In this video, we will explore the hidden story behind early quantum mechanics.
Planck's approach to Blackbody Radiation was to analyze the entropy as a function of energy. To make both high-frequency and low-frequency data consistent with the Second Law of Thermodynamics, he included an additional "guess" term proportional to the frequency (hf); this results in Planck's Law which is strictly classical. Planck's subsequent application of Boltzmann's Statistical Mechanics to justify his guess then led to his revolutionary conclusion that the material of the walls emit and absorb radiation in discrete quanta. A paper titled "Planck?s Route to the Black Body Radiation Formula and Quantization" by Michael Fowler (7/25/2008) gives a nice discussion. "Theoretical Concepts in Physics: An Alternative View of Theoretical Reasoning in Physics" (1984) by Malcolm S. Longair contains more details.The full story illustrates Planck's physical insight and tenacity in approaching a problem; it's very inspiring.
Quantum mechanics ? the crown jewel of modern science and an infinite inspiration of technology.While names like Max Planck and Albert Einstein are often hailed as their founders, the true beginning started with a challenge by German physicist Gustav Kirchhoff. Unfortunately, this part of the history is seldom mentioned in the discussions of quantum mechanics.What followed was a relentless pursuit by some of the greatest minds in history ? Stefan, Boltzmann, Wien, Rayleigh? and finally, Planck.This video is dedicated to this fascinating hidden history, which eventually led to the birth of quantum mechanics by Planck and Einstein Timeline: 0:00 - 0:39 Intro0:40 - 1:13 Kirchhoff's work on Spectroscopy1:14 - 2:06 Short bio of Kirchhoff2:07 - 2:42 What was Kirchhoff's challenge?2:43 - 4:39 Absorption of radiation 4:40 - 5:00 Emission of radiation5:01 - 5:53 Striking conclusion by Kirchhoff5:54 - 10:25 Description of Kirchhoff's challenge10:26 - 10:45 Tyndall's experiment10:46 - 11:31 Stefan-Boltzmann result11:32 - 11:50 Wien's radiation formula11:51- 15:16 Enter Max Planck15:17- 15:53 Chronology
This video is about the biggest lie people are told about the double slit experiment: that electrons are particles when they're observed, but waves when they're not. The truth is much more interesting. Paper about the single photon at a time version of the experiment:https://pubs.aip.org/aapt/ajp/article/84/9/671/1057864/Video-recording-true-single-photon-double-slit
electrons are particles when they're observed, but waves when they're not.
I solved the Schrodinger equation numerically to avoid the most complicated step of solving the differential equation but surprisingly, it taught me an important lesson.
Nice. I always find it very helpful to see a problem worked through when it shows not just the correct paths to the solution, but also the wrong paths, and why things do not work. Another key point you may want to address is the need for complex numbers. Maybe one day you can explain entanglement computationally!?
This took me back to my Master's thesis which I did over forty years agodoing numerical solutions to Schr?dinger's Equationbut I didn't have access to a personal computerI had to write programmes in Fortran IVand submit them to a queue for processing.I never had the graphics so it is interestingto see what a simple example looks like.I am thinking - having found my thesis recentlyfirst write it in LaTeX and rewrite the programmesso I can see what I was writing about.My original thesis was typed by a secretary and I handwrote the equations and graphs LOL
Mathematica 14 has the SchrodingerPDEComponent function that makes setting up these systems pretty easy. The documentation for this function has many examples including particle-in-a-box, harmonic oscillator, double-slit, and Aharonov-Bohm.
This video shows the proper intuition for the famous teaching of quantum mechanics: Heisenberg's uncertainty principle.
Heisenberg didn't use Schroedinger's wave function. Heisenberg used noncommutative quantum algebra that his teacher, Born, realized was matrices math. Pascual Jordan developed the matrices math for Heisenberg.Yes, but the Fourier duality is equivalent with the fundamental commutation relation. It was Weyl who derived the wave mechanical uncertainty principle, i.e., the Heisenberg-Weyl inequality.
I don't understand why other channels don't explain this fact. They make it seem as though uncertainty is some uniquely weird quantity. Thank you for clarifying.I still wonder where the motivation for multiplying the standard deviations of position and momentum comes from. The only thing I can think of is that it is useful to find the correlation of position and momentum. If I remember correctly, the product of the standard deviation of the two random variables is part of the equation.
The sin waves is also a bit misleading, the complex function is more like the component sum of a sin wave and its dervative. Innterms of a magnitude of a vector at any point in particular in x for instance. You can do real functions instead by squaring a sum of derivatives and magnitudes of a real position function. For a sin function as the wavefunction for position space, take the amplitude of the function, and the amplitude of its derivative function, and ad them like components of a vector, then square the magnitude, and that's basically the same as a complex function [sinx , cosx].
04:29 - This uncertainty is the try to replace physics by statistics.
Almost 125 years ago, Planck presented a paper to the German Physical Society that launched quantum mechanics. But, how did he come up with such a weird concept? Textbooks say classical physics predicted an energy curve that flat-out contradicted experiment, and Planck heroically patched it with quanta. Unfortunately, that's not the whole truth. In this video, we unravel the real story of Planck's route to quantum.
Best video I hav e watched all year. So many lessons to learn for today's scientists from this slice of history by unveiling the context and underlying motivations. The fact that young people these days question textbooks, go back to the original sources, and then go through the effort to disseminate what they learned, gives me so much hope that we will soon break through decades of stagnation in science.
A paper titled "Planck?s Route to the Black Body Radiation Formula and Quantization" by Michael Fowler (7/25/2008) gives a nice discussion. (You can find this online.) "Theoretical Concepts in Physics: An Alternative View of Theoretical Reasoning in Physics" (1984) by Malcolm S. Longair contains more details in "Case Study 5". I bought my copy of Longair when it was new, and I was a lot newer. The full story illustrates Planck's physical insight and tenacity in approaching a problem; it's very inspiring.You produced an excellent presentation!
Planck's "second theory," also known as his "theory of quantum emission," proposed that while the emission of radiation is quantized (occurs in discrete packets or quanta), its absorption is continuous, following classical physics. This differed from his initial theory where both emission and absorption were treated as quantized processes. This distinction was seen by some as a less radical departure from classical physics. Here's a more detailed breakdown:Planck's Initial Theory (1900):In his initial theory, Planck proposed that energy is exchanged in discrete packets called quanta, which are proportional to the frequency of the radiation. This explained the blackbody radiation spectrum and resolved the ultraviolet catastrophe. Planck's Second Theory (1911):In his second theory, Planck modified his approach, suggesting that only the emission of radiation is quantized. He proposed that the emission of energy quanta follows a probabilistic law of electrodynamics, while the absorption of radiation occurs continuously, in accordance with classical theory. Motivation:This modification was partly motivated by the desire to reconcile his quantum ideas with classical physics, as some physicists found his initial theory to be too radical. Zero-Point Energy:Planck's second theory also introduced the concept of zero-point energy, which is the minimum energy that a quantum mechanical system can possess even at absolute zero temperature. Legacy:While Planck's second theory was eventually abandoned by most physicists by the 1920s, the concept of zero-point energy remained and became a fundamental part of quantum mechanics. In essence, Planck's second theory attempted to find a middle ground between classical and quantum physics by quantizing emission but not absorption.