Quantum physics Definition and 717 Threads

Quantum Mechanics of Particles and Wave Fields by Arthur March... Does anyone know of the author? I think I found an error in this book. :(

Homework Statement Find the wave packet Ψ(x, t) if φ(k) = A for k0 − ∆k ≤ k ≤ k0 + ∆k and φ(k) = 0 for all other k. The system’s dispersion relation is ω = vk, where v is a constant. What is the wave packet’s width? Homework Equations [/B] I solved for Ψ(x, t): $$\Psi(x,t) =...

Homework Statement Does the n = 2 state of a quantum harmonic oscillator violate the Heisenberg Uncertainty Principle? Homework Equations $$\sigma_x\sigma_p = \frac{\hbar}{2}$$ The Attempt at a Solution [/B] I worked out the solution for the second state of the harmonic oscillator...

I'm currently in my first QM course and we have griffiths as our textbook. Although Griffiths is a great read I'm having trouble really conceptualizing QM ideas. We've only covered infinite potential well and wave packets as of now. Are there any additional resources or textbooks in which they...

Or does ontological probability exist? I was reading an article that came up in my google searches ( https://breakingthefreewillillusion.com/ontic-probability-doesnt-exist/ ) ignore the free will philosophy stuff. But the author makes the claim that ontological probability simply does not...

I am particularly wondering about zircon, element 40. I notice that its isotopes decay by either electron emission positron emission or electron capture, and I was curious to know whether this is established experimentally or if quantum physics is able to predict which isotopes will decay via...

I see this has been already discussed but the old threads are closed. EPR before EPR: a 1930 Einstein-Bohr thought experiment revisited "In this example, Einstein presents a paradox in QM suggesting that QM is inconsistent, while Bohr attempts to save consistency of QM by combining QM with the...

The question relates to the deterministic views of people like Descartes or Pierre de Laplace, the infamous "an omniscient intelligence who could know precisely the position and momentum of every single particle in the universe would be able to predict the future with total accuracy, past...

Greg Bernhardt submitted a new PF Insights post Interview with Astrophysicist: Adam Becker Continue reading the Original PF Insights Post.

I'm not asking about the math here, I'm interested in the wording physicists use in QP / QM / QFT. I'm frequently confused, when I'm reading threads here. They often start completely underdetermined and often also just wrong from a mathematical point of view, but seemingly, physicists know what...

can we find causality in quantum mechanic like the classical physics ?

Is it possible that the speed of light exists because we cannot move faster than our particles? I.e. the speed of electrons that create the electromagnetic force that hold matter together.

Hello, I am 12 years old in 6th grade and love physics and Quantum Physics, I would love an explanation of Quantum Physics and Topological Quantum Matter.

Hi at all, I've the following question: How the fondamental particles (electrons, protons) are seen as matter waves, what shape and size should be these waves? They are wave-packets?

I have an interview lined up with UC Berkeley's Adam Becker. http://freelanceastro.com/ I am looking for a few "foundations of quantum physics" questions for him. Now is the chance to get that question answered!

How quantum physics is understood? I am wondering what the heck is quantum physics. I love physics in that classical way in high school, but seeing the equations of quantum physics there is fear in my mind . Is it possible for me to understand each and every concept and derive equationas I...

Hi, I am new to the Pilot Wave theory. In my understanding this theory gives a hope for reconstruction of the realism. But I have several maybe naif questions. What is the wavelength of the pilot wave? Is it the same as deBroglie wavelength formula? Very often people use the walking droplets...

Some books argue that typical coordinate transformations such as space translations and rotations are represented in quantum mechanics by unitary operators because the Wigner's theorem. However I do not find any clear proof of this. For instance, suppose 1D for the sake of simplicity, by...

Hi everyone, I just have some confusion regarding Planck's and Einstein's equation. The following is an explanation of the photoelectric effect using Einsteins theory: Light is composed of photons. Each photon has energy hf and mass hf/c^2. When ultraviolet photons are brought to rest by zinc...

Hi, I have an assignment to derive the two following expressions: R(J)-P(J)=2B'(2J+1) R(J-1)-P(J+1)=2B''(2J+1) where Bis the rotational constant and prime ' stands for upper level and bis '' for lower level. Bv=Be-α(v+1/2) using the selection rules (I guess in this case ΔJ=±1) and...

I am doing a GT project for elementary school. The questions I have to ask are not too complicated, and I only have 2 questions. I know that during the teleportation of a particle the scientists are using quantum entanglement, but how do the scientists actually entangle the particles, and how...

Anyone read the book Advanced Quantum Physics by Hans Paar ? Is this somewhat analogous to Sakurai's advanced quantum mechanics? If anyone used it, can youcomment on what you used it for (e.g. was it a bridge between QM and QFT)? I happened to see this book on amazon and from the excerpt, it...

Hi, I was looking for a quantum physics phenomenon including in quantum field theory where the solutions of a related phase-plane system (i.e. the harmonic oscillator) have a spiral sink in the phase portrait? The harmonic oscillator has saddle points in the phase-portrait, given its eigenvalue...

i want an article or video that i can start with at the journy of understanding the basics of quantum physics and quantum mechanics i don't want a book because in my country i would not find this types of books every where it's unique to find them thanks

First, I must say I'm in no way a physicist, I barely understand the basics of quantum physics. And what I will talk about is mostly philosophical anyway. I don't believe myself that "we are in a simulation", it's just food for thoughts. As the title says, it's about 2 quantum things that struck...

I am trying to learn all about Quantum Physics on my own but I am struggling to find credible sources of information. As you are probably aware the internet is filled with misconceptions, crackpot science and weird stuff about spirituality (at least that's what I find when I try and research...

I don't have much of a background in quantum physics so be patient with my questions please. Basically I want to know how does entanglement actually work? Is information being transferred faster than we can detect it or is there some invisible link between particles that causes the phenomenon we...

Hi All, I am brand new here, still trying to navigate the website so please forgive me if this is not the appropriate space for the following. I missed the recent topic, "How do you understand EPR & Bell's Theorem? " No new threads permitted now but I would like to express a summary view as my...

I've read Arnold Neumaier's excellent Insight article on virtual particles, but I'm very confused about one thing: Observable particles are considered to be on-shell, and as 'asymptotic states' at time +- infinity. Now, in a scattering experiment, I may produce a new particle, which will travel...

What are the very good books for practicing variety of and a lot of problems covering every concepts (analytical ,mathematically interpreted and intuitive )related to the topic .Books can be of physics or applied physics bcoz I have seen a book on applied mechanics like Housner-houdson .

Is it possible to create a ‘Transverse Field Ising Spin’-compatible Super Hamiltonian? I want to apply the Super Hamiltonian to this paper: https://arxiv.org/abs/1612.05695

Hello! Recently I found this article: http://quantum-journal.org/papers/q-2017-07-14-13/pdf/ Being familiar with some basis of quantum formalism, I, nevertheless, experienced several difficulties with understanding of the theorem described in this paper. I would really appreciate if someone...

Relative to the observer, objects shorten when approaching the speed of light exponentially. Does this rule also apply to the wave function? Does this rule also apply to massless particles like Photons? Or am I just simply forgetting something?

Homework Statement construct ψ(x,t)^(2) where ψ(x,t) = 1/5(3ψ_0(x)e^(-iE_0t/ħ)+4ψ_1(x)e^(-iE_1t/ħ). I know we square it but we have to find E_0 and E_1 and put it in. Homework Equations E_n = (ħ^(2)k_n^(2))/2m = (n^(2)π^(2)ħ^(2))/2ma^(2) The Attempt at a Solution E_0 = 0 and E_(1) =...

As far as I know there are Mesons (quark-Antiquark pair) and Baryons (three quarks). But are there Hadrons which contain more than 3 Quarks?

Hey there! My name is Karol and I am 16 years old. I joined the Physics Forums because I have many questions and ideas on how the universe might work. I am interested in General Relativity and Quantum Physics and I often attempt to unify both (finding the world formula :D ). My dreams are to...

I learned that for nuclear fusion to take place, particles must overcome the electrostatic field but what exactly is it? And how is it created/formed?

The first light atomic nucleus with a second face Physicist found the first light atomic nucleus in a lab that had too little resources. http://sciencefeeds.weebly.com/journal/the-first-light-atomic-nucleus-with-a-second-face

Homework Statement [/B] I'm trying to solve the following problem. (a) was easy but I am stuck at (b). Homework Equations [/B] Since we are told that the Hamiltonian is conserved, and the answer is in terms of the uncertainty of H, I assume I have to use the conservation of uncertainty...

I am a UK A levels ( high school) graduate and on my gap year I want to learn quantum physics on my own and I really want to understand it properly. What are the best resources and approach to learn it should I watch Feynman lecture series or any playlist in YouTube? Are there any books for high...

Hello I have a bunch of issues with the various interpretations of quantum physics. I'd like to dig into it but most textbooks on the topic just throw in your face a bunch of equations and tell you "that's the way it works" Intead, I'm looking for a detailed history of the experiments that led...

Hello all. I am trying to determine what is the effect of having photons that are distinguishable undergoing a quantum interference process. To do that, I try to generalize the Hong-Ou-Mandel effect, and try to determine what are the terms that appear as a function of the product of the creation...

Is classical physics more than just the quantum physics of a large number of particles and quanta? Thanks for your thoughts.

Hello, I've a following question: Is necessary know well func. analysis, and all its theorems to handle well quantum physics...?

I'd like to be a quantum physicist in the future, so I'd like to do quantum properly, but there are so many books out there, and it's a bit hard to choose. I've already completed 1 year of undergraduate physics, so I think I know enough classical mechanics. I've also covered calculus...

Hello mates. I was doing some research about Rydberg atoms, and I came up with this question: what's the energy of an electron in n energy level in an atom which is NOT hydrogen-like, that is, an atom with more than 1 electron? How can we calculate it? What if the electron we are studying is in...

What does mainstream quantum physics currently say about consciousness?

What are some unanswered questions of quantum physics?

As a 14 year old, my access to resources is limited to what I can find on my phone or occasionally in the library. With this consideration, can anyone recommend some good online resource for learning quantum physics and nuclear physics. I already have the background knowledge, I understand...

Hello folks. This thread is open for discussion among those who want to explore the similarities between the experiential principles found in art and physics.