Experiment Definition and 1000 Threads

Consider a box whose walls are mirrors. Suppose we trap a bunch (yes, it's vague) of photons inside the box. They will not escape, or assume that a major part of them will not escape the box. Now suppose we have a way of decreasing the size of the box at our will, but possibly obeying the laws...

What would happen if a youngs double slit experiment is done with different slit sizes? I get the feeling that the intensity might never be zero as the waves might never cancel out completely. Am I right? How should I analyse the Intensity? Would I have to do something like what is done while...

I have a misunderstanding about the beam splitter in this experiment High fidelity entanglement swapping with fully independent sources Rainer Kaltenbaek, Robert Prevedel, Markus Aspelmeyer,Anton Zeilinger http://arxiv.org/pdf/0809.3991.pdf Part of the diagram is reproduced here Two photons...

Homework Statement I experimented with standing waves on an oscillating string, and I was asked to calculate the absolute error of µ (linear mass per unit length). I don't know how to calculate it, so please help me. I loaded 100g, 200g and 300g on the string. Below are tabulated data of the...

Homework Statement So I've spent many hours on here and deep deeeeeep in my textbooks trying to learn things...that pertain to the Egg drop experiment I am almost done with everything I need but I was wondering. I've read that it takes approximately 25 Newtons of force to break an...

In Principle of equivalence, we indroduce to the theoram by a lift experiment, my question is why the lift is fully closed one, why the observer in lift forbidden to observe out side world

Homework Statement a) Explain why a pattern of bright and dark fringes visible on a screen when a light is shone through a double slit. b) Upon using Thomas Young's double-slit experiment to obtain measurements, the following data were obtained. use this data to determine the wavelength of...

1. The problem statement, all variables and given/known da Homework Equations Interference minima is asinΘ=nλ/2 where n=1,3,5,7... [/B]The Attempt at a Solution Putting ab/(2sqrt(b^2/4+d^2))=λ/2 for first order minima And solving for d I get (b/2)*sqrt((2a/λ)^2-1) in which only the 2 factor...

Morning mates, I've peformed Galileo's experiment with inclined planes, using a ramp of 88cm (divided in 4 parts of 22cm), inclined by a height on the right-edge of 4cm. I've measured the following, 1/4 of the ramp (22cm): 1.75s (error of 0.1s) 1/2 of the ramp (44cm): 2.70s (error of 0.1s) 3/4...

In Michelson Morley experiment we use a moving mirror to reflect light and then we find out that light moves with c regardless of the speed of the mirror. My question is why do we need a theory to replace the galilian composition of velocities?i mean this can be explained by saying that...

I want a book that explains everything about Michelson Morley experiment. The one that says light moves with c regardless of the speed of the source and also the one that says light appeared to move with C for all observers.

I'm doing the experiment for a project using a setup as so: https://imgur.com/a/7vfg2 In the derivation of the formula I used the amplitude of the oscillation on the ruler of the laser, basically taking it as the arclength of the arc drawn by the laser spot as the bar rotates inside the...

Hello everyone. I want to ask some questions about dcqe experiments results which are bugging my mind. It is so hard to find reliable sources in my native language so I'm here. Also sorry for my scuffed english. Assuming we all know the famous experiment setup, I am directly passing to the...

Hoping to get some help on a stability analysis of this setup...

I have previously posted Preserving local realism in the EPR experiment . I have since given up on simulating local realism since I now understand it is impossible. However I have not given up on causality. Attached is code that simulates the EPR experiment and gives the same result as what...

Suppose we have a particle, let's say an electron, in a box of size D. And we add another one next to it at some distance L center to center. How do we solve for the wavefunctions of the electron. Can it be solved in normal QM or do we need QFT. Thanks.

Homework Statement Ok so in my lab we have been given a set-up as shown below Minus the horse shoe dector on the right hand side. During this set-up up we need to find the point where the balance point and centre of gravity are equal (as I understand) here is exactly what my script say...

I have some serious issues trying to understand the idea of the spin in the context of the Stern-Gerlach experiment and would appreciate some assistance! Assuming that a homogenous magnetic field ##B## in the "North-wards" ##z##-direction, assume that there is a magnetic dipole moment ##\mu##...

So as we know at the bottom of the ocean we have water cooled to 0-4 degrees celsius which is very dense and also compressed due to the pressure. Imagine we lower a few kilometres long pipe to the bottom of the ocean (it's made of material that is strong enough to sustain pressure). It's closed...

Hi there, I'm looking for some interesting activities regarding nuclear physics in high school. I already have: - building a cloud chamber with dry ice or peltier modules - simulating radioactive decay with dice - simulating Rutherford's experiment hitting with glass marbles a hidden target...

Hello, I have found a YT video which shows some kind of experiment. You see a wooden toothpick suspended on a spider's web single thread and covered by a jar. Then a you see a man who holds a few plastic straws in his hand. He closes them to the toothpick and it slowly moves (which is seen if...

Hey, I'm trying to adapt the Bragg condition for the David-Germer experiment, so I can then use their experimental results to show that the measured wavelength is compatible to the wavelength theorized by De Broglie. However I'm having issue with the calculation, any help would be much...

Homework Statement Homework EquationsThe Attempt at a Solution Time period of a simple pendulum is given by 2π√(L/g) . By uniform mass distribution , I am assuming density of mass of bob to be constant . I don't understand how time period depends on the mass of the bob of a simple pendulum .

Hello, Disclaimer: I have read other posts and understand it is important to reference ‘sources’ and that popular science articles / videos can be a source of annoyance. However, I am struggling to: A. Find an answer to my question, and/or B. Understand if my question is even valid. I hope...

Hi, I have two questions concerning the double slit experiment in the scenario where we fire one photon at a time and it interacts with itself to create an interference pattern over time: - Does the photon actually interact with itself or with the photons fired before/after it? - What happens...

In the 2 slit experiment , what would be the result if we put a dedector on both slits? would we get an interference patern?

Homework Statement I'm trying to figure out the setup of an experiment I have to complete. The experiment calls for a rubber band to be secured by rods on the sides, and for a clothespin to be attached to the rubber band. I have to figure out how far back the clothespin needs to be pulled down...

I have two questions about the following type of scenario: We have a laser sending photons through the usual double slit apparatus giving us the usual interference pattern, except that now we introduce some physical matter (that are not photons) that the photons will interact with before going...

I can't read the tons of posts and replies about one-way light speed in this forum. I was criticised once for sustaining light speed should be equal in both outward and return trips and Einstein's method of syncing clocks as the only reasonable one. Then I studied some scientific articles gently...

I realize the 2-slit experiment is discussed at the beginning of countless QM books and YouTube videos. I have read the excellent exposition in the first chapter of Feynman & Hibbs, and appreciate that (using Feynman & Hibbs language): A. any determination of which among various alternative...

What is wrong with the idea that the spooky correlation in the EPR experiment is simply the result of the initial difference in rotation between the two polarizers in this experiment? So if you rotate one of the polarizers relative to the other polarizer, that initial act of rotation is what...

The Particle Data Group keeps a running, subject matter organized summary of the state of the art experimental results for the experimentally measured properties of hadrons and measurements of fundamental physical constants that is updated at least annually. Is there any comparable group that...

Homework Statement I am having a issue with calulating my errors for this particular experiment the reason I will detail below. I have also print sceend in the section of my lab report to show the experimental setup etc. Lab Script So in the lab during the experiment the tesla meter...

Homework Statement Calculate the charge on each oil drop and determine the elementary charge on an electron given the following: Voltage (Attached) d (Distance between two charged plates) = 0.10m m (Of the droplet) = 1.57x10^-15 kg g = 9.8 kgm/s^2 Homework Equations q = mg*d / ΔV The Attempt...

Hi, I arrived at a paradox today which I cannot explain myself. I was watching some physics videos on youtube and among them some were about lenz law and faraday disc workings. Now I know and understand the classical examples of why there is current generated when the magnet moves together with...

Hi everyone! Sorry for my bad English! I read old posts in this forum, googled it and still can't figure out one thing: What other explanation could there be, other than a random event in the future determined if the photon behaved as a particle or wave in the first detector? Thanks a lot! I...

Certainly a wooden ball and a stone fall with the same velocity. Would a balloon of cold air fall with the same velocity as a balloon of hot air? As a corollary, why does hot air rise over cold air? If you claim that cold air is denser, then the same argument fails when you compare a wooden...

Hi, I'm trying to understand in a simple, non-mathematical way the basic concept underlying why a particular, very recent experiment turned out the way it did. The experiment, by Serra and Lutz entitled 'Reversing the thermodynamic arrow of time using quantum correlations', demonstrated an...

On the following link https://physics.stackexchange.com/questions/183961/modified-double-slit-experiment-two-electron-sources-instead-of-two-slits there is a discussion of the modification of double-slit experiments where two electrons sources are put in place of the slits. The conclusion is -...

Hi! So it's new for me to do physics lab that way and my teacher is asking us to define the independant, dependant and controlled variables of every lab we're doing. I'm not quite sure what they refer to... For example, in a moment of inertia lab (see picture), I am asked this question. The...

Background The chart above, via Lubos Motl's blog which is standard in any textbook talking about supersymmetry, illustrates the running of the the inverse of the Standard Model (SM) and Minimal Supersymmetric Model (MSSM) coupling constants with energy scale for the electromagnetic force...

It's written in Kubo's textbook: I tried getting (2) from (1), but I get something different, I get: ##T\partial V / \partial T - V = TR/p+TRB+RT^2dB/dT-RT/p-RTB = RT^2dB/dT##, how to resolve this conundrum? Thanks.

Hi, I'm confused a little about the gold foil experiment. I tried to put myself in Geiger's shoes, the author of the experiment. I'm firing alpha particles at a gold film, given that the plum pudding model is the pinnacle of human understanding of the atom, meaning I believe matter is made of...

Is the object of an experiment a variable?

The article https://en.wikipedia.org/wiki/Malament%E2%80%93Hogarth_spacetime, the possibility of a space with a "worldline λ and an event p such that all events along λ are a finite interval in the past of p, but the proper time along λ is infinite" is discussed, and the suggestion is made that...

Hello, we are Maylis, Clara and Hélèna. We are students from a french high school in a class of «première scientific» (french equivalent of 11th grade) This year we have to be marked on Science more precisely on Physics. As a subjet we choose «the roundness of the earth: how Science is used to...

So I am doing the charge to mass experiment and determining the relationship between: 1. accelerating voltage and radius formed by the electron beam 2. magnetic field strength and radius formed by electron beam Theoretically I should obtain an equation of the form: r = (1/B) *sqrt(2mV/e) where...

Hi everyone! Sorry for the bad english. I'm a psychologist from Brazil, so I don't know much of physics nor English. I'm having a hard time understanding his setting. In a very simple way, he made two entangled photons, each went to a polarization analyzer, that was set to random positions...

I'm currently carrying out an experiment with Fraunhofer diffraction. It involves shining a laser beam through neural density filters, a lens and a diffraction grating, to create a diffraction pattern which is then picked up with a CCD camera, to find the intensity of the maximal peaks. However...

I've always struggled with circuits and never got a firm handle (hence the very basic questions...please bear with me). What I understand of Lenard's Experiment: Light hits the emitter plate and some electrons fly off. ...lol yeah that's about it. Here is one major confusion that I have: Not...