Classical music is art music produced or rooted in the traditions of Western culture, generally considered to have begun in Europe after the fall of the Western Roman Empire in the late 5th century CE and continuing to present day. Classical music refers to Western musical traditions considered to be apart from or a refinement of Western folk music or popular music traditions. The major periods are the medieval (500–1400), Renaissance (1400–1600), Baroque (1600–1750), Classical (1750–1820), Romantic (1800–1910), Modernist (1890–1975) and Postmodern era/Contemporary (1950–present) eras. These periods and their dates are all approximate generalizations and represent gradual stylistic shifts that varied in intensity and prominence throughout the Western world.
The term "classical music" did not appear until the early 19th century, in an attempt to distinctly canonize the period from Johann Sebastian Bach to Ludwig van Beethoven as a golden age. The earliest reference to "classical music" recorded by the Oxford English Dictionary is from about 1829.European art music is largely distinguished from many other non-European classical and some popular musical forms by its system of staff notation, in use since about the 11th century. Catholic monks developed the first forms of modern European musical notation in order to standardize liturgy throughout the worldwide Church. Western staff notation is used by composers to indicate to the performer the pitches and durations for a piece of music. It includes both sacred (religious) and secular music. In contrast to most popular styles that adopted the song (strophic) form or a derivation of this form, classical music has been noted for its development of highly sophisticated forms of instrumental music such as the symphony, concerto, fugue, sonata, and mixed vocal and instrumental styles such as opera, cantata, and mass.
Hello,
I have a fundamental question about why state space control techniques are superior to the classical methods. I l know that you can control a system with multiple inputs and outputs for several states using state space control, however, can't the same thing be done in classical control...
I read in the Britannica Encyclopedia yesterday that Rene Descartes rejected the idea that a water pump works because nature abhors a vacuum, and instead said that it works "by the weight of the water which counterbalances that of the air". I have an idea of the two contrary concepts opposed...
Hello. I am currently reading on electromagnetism in university. However, I feel that I sometimes get lost in the the math in an otherwise excellent book (Field and Wave Electromagnetics by David K. Cheng), so I would like to ask, if somebody knows a good, steady resource for understanding the...
What I understood from Quantum Entanglement (QE), is that measuring the spin of one of two entangled particles in one location gives the spin of the other particle in other location no matter how far is the later. What I can also understand is that the same concept is applicable in the classical...
Hello everyone, I have a little problem with some transformation.
I wonder how i can get that result. Can somebody explain it step by step?
The " ' " means derivative. Thank you for your time ;)
This is a diagram of a pitot-static tube. My question is however not related to its applications but rather, what causes the liquid to rise up the static tube? The static tube is at right angles to the fluid flow. I understand that this is a very basic question but I can't seem to get my head...
A paper published in 'Gravitation and Cosmology', [21, 208 (2015)] and on today's physics ArXiv claims to have found a solution to the Wheeler-DeWitt equation that exactly corresponds to the classical evolution of a Friedmann model with appropriate matter/energy density: Exact Classical...
I just discovered the concept of phonons and the story of Brian Josephson (from reading "Sync" by Steven Strogatz).
What the h...?
So Phonon's are collective excitations of classical stuff made from QM ensembles, excitations made possible by the QM properties of the ensemble members? Are...
Hi all! I was directed (on another thread) to professor Leonard Susskind's first lecture on classical mechanics. I learned a lot from it, however he introduced a "rule" for "acceptable" classical fields/equations that I have a little trouble with. He explains classical mechanics as if you know...
Homework Statement
A string wraps around a uniform cylinder of mass M, which rests on a fixed plane with angle θ. The string passes up over a massless pulley and is connected to a mass m. Assume that the cylinder rolls without slipping on the plane, and that the string is parallel to the plane...
We always consider the accelaration as a constant thing, while calculating the freefall problems. What if we try to calculate the real. I mean taking the accelaration GM/x^2. I tried it but i could not handle that integral(Just graduated from high school). I would be happy if you reply.
Thank you
https://www.osapublishing.org/optica/fulltext.cfm?uri=optica-2-7-611&id=321243
"In our experimental test, we used light whose statistical behavior (field second-order statistics) is indistinguishable from classical, viz., the light from a broadband laser diode operating below threshold. Our...
I have a degree in Electrical Engineering and I want to learn classical mechanics in my free time. I originally planned to just learn out of a textbook, but I saw the university near me has a graduate course in classical mechanics this semester, and I am considering enrolling in the course...
Homework Statement
Consider two objects with masses ##m_1## and ##m_2## exerting forces on each other with magnitude ##F##. If no other net forces act on the objects, they obey the equations of motion
##m_1\ddot r_1=F##, ##m_2\ddot r_2=-F##
Show that the corresponding equations of...
Earnshaw's theorem http://en.wikipedia.org/wiki/Earnshaw's_theorem gives a straightforward reason why we can't have a static equilibrium for a system of point charges. For some time I've been trying to find out if anyone's worked out a similar proof for the impossibility of a dynamic...
So the standard way to introduce scattering classically is through the two body problem for a central force where we move to the centre of mass reference frame and all the dynamics is explained by a one body problem for the separation vector ##r_{12}=r_1-r_2## with a reduced mass ##\mu=\frac{m_1...
According to Maxwell's Equations, the classical vacuum permittivity and permeability have a very important role: They determine the speed of light. But it seems like these two important concepts are not as precisely defined in the quantum world. Are there rigorous analogs of these two...
Hi everyone.
I'm confused with the balance of energy in this situation (I'm comparing the mechanical energy, initially, at rest, at a height = h, and then, at the end, at height = 0). It doesn't seem to be fine, maybe I missed something.
I'd appreciate some help - Everything is in the .jpg...
I was recently reading about quantum computers because I once asked a teacher with more experience in the field "What was the origin of the quantum speedup" with his answer being quantum parallelism, which I kinda understood at that time, but I forgot about it. So, the other day I was thinking...
Dear all,
I'd like to know what is the place/use of complex variables (and complex analysis) in classical mechanics. By the way, is there any?
Thanks for your help. Best regards!
I'm currently collating my own personal notes and would really appreciate some feedback on my description of the relativity of position and velocity in classical mechanics. Here is what I have written
"Position is clearly a relative quantity as two inertial frames S and S' displaced by a...
What is the relation between classical from quantum vs measurement problem. On one hand they seem to be related on the other they seem to be of different nature.
We always see our screens on front of us and not 100 meters away, that we say is classical object although the screen is a quantum...
The QED theories merely state that a photon has spin and momentum. Are there any reasonable mechanistic descriptions, perhaps in terms of variations of E and H beyond the infinite plane wave (which is also not helpful)?
This question is inspired by ephen wilb's https://www.physicsforums.com/threads/quantum-theory-of-others.816818/#post-5130620.
In Bohmian Mechanics, everything is exactly as in classical probability theory. How, from the point of view of BM, does the measurement problem arise? Since the...
I have a question that's been gnawing at me recently. In classical physics, momentum is mass times velocity, which makes sense, take the mass of an object, calculate the velocity and you are left with a vector quantity of momentum.
In quantum physics, we have momentum p=h/λ. This doesn't seem...
Homework Statement
A stopping potential of 0.50 V is required when a phototube is illuminated with monochromatic light of wavelength 600 nm. Monochromatic light of a different wavelength is now shone on the tube, and the stopping potential is measured to be 1.1V. What is the wavelength of this...
Good afternoon all,
A few days ago, I had been reading a book on general relativity and cosmology by Dr. Brian Greene, in which something was written that I found to be very profound. (At least, from the standpoint of my own ignorance on the subject.) I was wondering if any professionals could...
In QM there is no cloning theorem that says "we can't clone or erase quantum state". But in classical macro world we can copy information and erase it.
If we should describe classical information as a very complex quantum state then we shouldn't be able to copy or erase it, right? And obviously...
In the quest of searching what are the basic ingredients of quantum theory that provide exponential speed-up to some quantum algorithms, a basic question that is pursued in the literature is when a quantum circuit (or algorithm) can be classically simulated efficiently. One example is this paper...
Hi there,
I am confusing on the statement that we have classical physics when Planck constant approaching zero. I search the similar topic in Physics Forums and I saw that most of the answers refer to the size effect. It argues that when we measure something in the scale of meter comparing to...
There is only one way to reduce the equations of special relativity (aka Lorentz Transformations) to the equations of Newtonian mechanics (aka Galilean Transformations).
In light of the above, why are there multiple ways to reduce quantum-mechanical equations of motion into classical equations...
Homework Statement
I'm asked to calculate the propability of finding a particle outside the classical limit for a quantum harmonic oscillator in it's ground state
Homework Equations
Ψ0(x) = a*emωx2/2hbar
When a = (mω/πhbar)1/4
The ground state energy E0 =hbar*ω2/2
The Attempt at a Solution
I...
Hello Seniors,
I have done BSc in Physics but couldn't take lectures of Classical Mechanics. I am Almost blind in this subject. Since it's a core course in Physics, so i need your help to understand the basics in this course. If anyone of you have any helping material/notes/slides etc which...
Hello all.
I have almost finished chapter 4 on energy in Taylor's classical mechanics book. But in the last example in this chapter I got confused. Here it is:
"A uniform rigid cylinder of radius R rolls without slipping down a sloping track
as shown in Figure 4.23. Use energy conservation to...
I'm an EE major doing a minor in physics. I have to take a standard intermediate electromagnetism course from the engineering department (which is just a more applied version of the physics department course). To get my minor, I was thinking about getting permission to use this course as a...
Hello, PF,
I'm going to be taking graduate CM next semester and the professor uses Landau's textbook instead of Goldstein, which I take is the usual text. What are the appreciable differences between the books and what kind of math will be needed? I have the basics-complex analysis, linear...
Hi,
Assuming the electron is a sphere of finite extent, the classical electron radius is derived by equating the energy of the electric field with mec2. For the computation of the field energy, we have to assume a charge distribution. Both constant charge density and constant surface density...
Homework Statement
The transition amplitude for the harmonic oscillator may be written as ##\langle x_2, t_2 | x_1, t_1 \rangle = N_{\omega}(T) \exp(i/\hbar S_{cl})##, where ##T=t_2-t_1## and ##S_{cl}## is the classical action. Let the wave function at ##t=0## be ##\psi(x,o) =...
[Mentor's note -- this post does not use the homework template because it was moved here from a non-homework forum.]
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Not sure how the extra velocity quantity appears after deriving both side of the velocity function to get acceleration. Please help.
I have read some parts of the book but noticed some errors that are to much for me to be uncomfortable for the rest of the book. Anyone encountered such problems with the book? Mainly, encountering too many errors? Even the errata in the publisher's site didn't gave sufficient corrections to the...
In many textbooks, the non-commutativity for the canonical pair is considered to lead to the major variaty from classical mechanism(CM) to quantum mechanism(QM), and change the Possion bracket into quantum commutator is a standard procedure called as canonical quantization. But in fact the...
I don't know very much about quantum mechanics, but if I'm correct, the future can not be predicted with certainty according to quantum mechanics. If this is true, how can we have formulas in classical mechanics that do predict the future with certainty?
Is quantum physics closer to the truth than classical physics, or is it just a different way of looking at the same problem? For example, the rules of baseball explain the behavior of baseball players better than the rules of football, and vice versa. The rules of these two sports are not...
Hello all.
I know both books cover some different topics, but for the topics they share, which one do you think is better?
I have checked the first chapters in both books, and, for the time being, I can't decide. So, if anyone of you have used these textbooks, maybe you can give me a piece of...
I seem to have two approaches that I've seen and understand, but I can't quite see how they relate.
1. Write a general time evolving state as a superposition of stationary states multiplied by their exp(-iEt/h) factors, and calculate <x>. We find that <x>=Acos(wt+b) as in classical physics (in...
As seen in the picture, this question is about an object moving in the x-y plane. But I don't get why in equation 8.9 the cross terms vanish? If anyone can help me, that would be really nice.
I would appreciate any help with the following question:
I know that for relativistic field theories, the stress tensor can be obtained from the classical action by differentiating with respect to the metric, as is explained on the wikipedia page...
What is a momentum space,a coordinate space and a configuration space? Are they in classical or quantum mechanics or both? What are their similarities and differences and when,where and how are they used? thank you in advance!
If i have a current of both negative and positive charges(i know that there is also current from only negative and only positive charges,i'm not confused) along an infinite wire of square cross-section,and the we put a homogeneous magnetic field normal to the current,then a Lorentz force acts on...