Diagram Definition and 1000 Threads

Trying to solve for the loop contribution when renormalizing a one loop ##\frac{\lambda}{4!}\phi^4## diagram with two external lines in ##d=4## dimensions. After writing down the Feynman rule I see that: $$\frac{(-i\lambda)}{2}\int d^4q \frac{i}{q^2-m_{\phi}^2+i\epsilon} $$ But I see no way to...

I have tried to draw a simplified diagram depicting the original Michelson experiment. I am only looking at the paths from the beam splitter to the mirrors at the end of the arms and back, Below, you can see the following: A space-time diagram with two space axes (x andy) and one time axis...

I'm trying to understand Newton's third law in the context of collisions. Assume that one body has mass M kg and is traveling in the positive x direction with acceleration A m/s^2. Assume that the second body has mass m kg and is traveling in the negative x direction with acceleration a m/s^2...

If you have γ+γ→γ+γ what would the Feynman diagram look like (time-ordering implied). I think it will be a square with four photons on each vertex but is this all there is to it or am I missing something?

So, to obtain the motion equations I initially plotted the free-body diagram (see picture). Then I’ve tried to get equations, but I’m not sure, do I have done it rightl. I will be gratefull if someone could help me.

Part of a project I am working on (part #3…see description below) is asking us to find the internal loads (shear and moment) and draw the corresponding shear/moment diagrams of the control arm shown below. It’s a little tricky to me, because all of the members associated with these type of...

Let's say you are riding a bike very fast, and then you sharply turn into a slide (where the bike is sliding perfectly sideways). I'm trying to calculate the angle that the bike would be leaning at, but I'm having trouble creating the free body diagram. Right now I have the normal force and...

Judging from FBD of the shelf, the answer will be either (B) or (D) because there should be horizontal force to the left to balance the horizontal force to the right by F, and by considering the torque, I think the answer will be (B) But I am confused about the direction of the normal contact...

Hey! 😊 One box contains ten production parts, four of which have a production error. Three parts are removed from the box one after the other without putting them back. We consider the following events : A : the first production part that is removed is OK B : the second production part that...

hi guys i need help changing the schematic diagram of this circuit to British Standards (BS 3939) i know that resistors are represented by boxes, but not sure about the transistors or Vcc and GND.

So I’m a high school physics teacher and I came up with the question above. However I haven’t given it to my students because I’m not sure what the answer would be. There is a force holding the gum up, and that force must balance the force of gravity. I’d probably call that an applied force, so...

I drew the Minkowski diagram, but I'm not sure if this is correct. From what I drew the angle between x and ct ##\approx 0## then the event is "inside" the light ray and will eventually reach A.

Hi, I'm struggling to find out how to create a phasor diagram. I have attached a photo of the question any help would be greatly appreciated. This is what I have attempted so far. It's question 2b I am really struggling with. I'm not looking for the answers just looking for some direction...

hi, can anyone please give me the list of measurement we can do ON Feynman diagram? Like , branching ratio, cross-section etc

While learning about Special Relativity I learned that we use the Transformation matrix to alter the space .This matrix differs for Contravariant and Covariant vectors.Why does it happen?,Why one kind of matrix (Jacobian) for basis vectors and other kind(Inverse Jacobian) for gradient...

I’m planning to write a 2D Minkowsky spacetime diagram generator tool. At this point, I am looking for help reviewing the specification. I am not looking for help with the implemenation. To be clear, I’ve written a complete specification, but it would be a waste if it was missing features that...

Hi guys, I'm wasting much time on this problem but still can't manage to get to a solution; I'll attach my attempt below. I started with drawing the FBD of the beam "sectioned" at point C, in order to find an expression for the internal shear force at that point and then equal that to zero...

I've seen both types of diagrams when drawing covalent dot and cross diagrams. And some students that I teach said that the electrons should be on the circles. But I do know that this is actually showing the electron overlap and electron field and in reality electrons are not in circular orbits...

I have a question regarding a homework exercise. My professor asked me to find the radial force in the free body diagram in the image included. There is a weight Fz from above and it is assumed that it is countered by the vertical component of both the Ff (friction force) and the Fn (normal...

Picture from the question Options: Option (B) is wrong because the both reaction forces have to be slanted since they are resultant of normal force and frictional force. I think option (C) is wrong because taking the point where the two rods meet as point P and comparing the torque produced...

Trolley should have zero acceleration.

It is my second "energy state diagram problem" and I would want to know if I am thinking correctly. First I have done some function analysis to get a glimpse of the plot: - no roots but ##\lim\limits_{x\to-\infty}U(x)=\lim\limits_{x\to+\infty}U(x)=0## - y interception: ##U(0)=-U_0## - even...

I'm reading a book called "Reality is not what it seems: the journey to quantum gravity" by Carlo Rovelli and I'm struggling to understand this diagram that is part of the chapter about special relativity. https://i.stack.imgur.com/JgBDJ.jpg Before this image Rovelli writes: "It's not...

I am wondering if the phase diagram of Carbon has been explored at very large electric fields. Can one make any theoretical guesses ? In specific I am interested in Pressure Vs Electric field and Electric field vs Temperature at fixed temperature and pressure respectively.

This is the problem, I managed to solve it, i just want to check if there is an alternative approach. Find my solution below; ##\vec x= -\vec a-\vec b-\vec y## ##\vec y= -\vec d+\vec c-\vec b## therefore, ##\vec x= -\vec a-\vec b+\vec d-\vec c+\vec b## ##\vec x= -\vec a+\vec d-\vec c##

Hi all., Just hoping to get a better fundamental insight into a few things. If we start with this: http://hyperphysics.phy-astr.gsu.edu/hbase/Kinetic/vappre.html so we have a closed container at a given temperature, then we can find it's saturation pressure. All good so far. In the following...

Please help me understand why this is a concept that has not been studied? The laser sail is really the only info I can find in this area using a laser from a fixed source. Using liquid nitrogen to cool the mirrors and reflecting lasers off of them for propulsion. I'm a Doctor of Pharmaceutical...

I am interested on how Feynman diagram is formed from a differential equation model of particle interaction wherein the incoming particles are not bound (e.g., separated neutron, proton and electron) and one or more of the outgoing particles are bound (e.g., hydrogen atom). However, I had never...

Answer: I know that when water evaporates, it absorbs heat, that's why the process is endothermic. I don't understand why the water would be cooled and some ice would form, when the water is supposed to evaporate. What causes some water to be separately cooled instead of evaporated? Thanks.

So I have been looking and trying different thing to synthesize rain noise like this: https://mynoise.net/NoiseMachines/campingRainNoiseGenerator.php but I cannot get it. and the graph that this sound makes did not help at all: can some make a block diagram of how to do this?

Writing about Engines and just muddled up diagrams and confused now. Which PV diagrams is for Compression Ignition and which one for Compression Ignition. I think one on left is CI and right SI. Cheers

The term for the electromagnetic interaction of a Fermion is ##g \bar{\Psi} \gamma_\mu \Psi A^\mu##, where ##g## is a dimensionless coupling constant, ##\Psi## is the wave function of the Fermion, ##\gamma## are the gamma matrices and ##A## is the electromagnetic field. One can quite simply see...

This is not really homework assigned to me but I wasn't sure where to post this. I'm trying to work through the book "Quantum Field Theory for Gifted Amateurs" by Tom Lancaster. I'm doing the questions on Chapter 19 to understand how to draw Feynman diagrams and work out their amplitude. One of...

I can only view each carbon individually so I don't see why the representations under incorrect is incorrect.

So all we have to do is find the current and power distribution in the steady state circuit. Create a phasor diagram. I don't exactly know how to tell it in english, but i think there is a thing I called c. & p. paths.

https://scipost.org/SciPostPhysLectNotes.10/pdf "Space expands behind the warp bubble and contracts in front of it, thus pushing the bubble forward at velocity v. The ship, which is at rest inside the bubble, moves along with the bubble at an arbitrarily large global velocity." If the ship...

this user will only use this function when something extraordinary situation, and that's how I stated it in the use case diagram. Is it a bad method of stating this way?

Can anyone help me with a kinematic analysis for the mechanism attached below? I need the outline of the mechanism, its notes and the necessary formulas to find out the transmission ratio and the rest of the values.

Step 1: I first started by reducing the inside of the block diagram of picture "bd" (the portion with G1 and the negative feedback G2) I obtained G1/[1 + G1G2] I'll call this term "F" Step 2: Then I'm left with two terms feeding into a summing point: F - G3 I'll call this term "K" I can...

My understanding of the n-correlation function is \begin{equation*} \langle \phi(x_1) \phi(x_2) ... \phi(x_n)\rangle = i \Delta_F (x_1-x_2-...-x_n) \end{equation*} Where ##\Delta_F## is known as the Feynman propagator (in Mathematics is better known as Green's function). Let us analyze...

Here's the diagram of the circuit: And here's the solution I found on a site on Google: I tried to follow through the solution given, but can't understand how it is applying current division rule to find current in QA and QB, and subtracting current values to find the current in AB is still...

Hi, Could you please help me with the queries below? Question 1: Do you think that the free-body diagram for M1 correct? It looks fine except that, I think, the arrow for M_{1}\frac{d^{2}}{dt^{2}}x_{1} should point downward. Question 2: Similarly, I think that the free-body diagram for M2 is...

The propagation speed of the wave is C/sqrt(9) = up if the length of the transmission line is 2m then every 10ns it will pass through the middle of the transmission line. But the switch in the circuit is opened after 5ns so after the current wave bounces off of the Load for the first time it...

Hi Im a bit confused with the example Can somebody explain and show to me how they got the bending moment calculations for the diagram in the attached. i understand it up to there. I started course late and can't ask for help. Thanks

Hello, i can't understand how does the author found this expression relating ##x_{c}## and v. I already tried by a lot of geometrical ways, knowing that the tangent of the angle between the dotted line and the x-axis should be v, but the results are illogical. Could you help me? I am start to...

Can we draw a Cooper pair in a band diagram? I know that Cooper pairs have very small energy (because they obey the Bose-Einstein statistics) but I was wondering if we could somehow plot in a band diagram and if yes how?

i saw this question on the internet. The people responding were of the opinion that the length##xy=1##, but no working...first of all is the answer ##1## correct? i am trying to find the steps to solution, i have managed to find an angle ##57.27^0## by cosine rule, i tend to think that i need...

If we were to use three-dimensional spheres to represent sets, could a 3D Venn diagram be constructed that could not be drawn as a normal 2D Venn diagram without changing the relationships between the sets?

I post the working in the attached file

Renormalization talk by Sean Carroll, "but then I could construct from that the following diagram with four lines in it": In previous talks he explained about diagrams and told interaction can be represented by many (even infinite) number of diagrams, "in" line can be changed to antiparticle...