0
votes
0answers
5 views

How does one go about designing a substrate heater for PVD? I need to design one that can go till 1000 C in Oxygen.

Can I just use a Kanthal wire and make a pattern on a ceramic base? Wouldn't such an exposed element get shorted when I use substrates like Silicon? But wouldn't a layer of ceramic on top of the ...
0
votes
0answers
5 views

Relationship between electrons (leptons) and quarks

I assert the following is true: Either: electrons are made up of (two) quarks Or: Quarks are made up of some kind of smaller particles, which also make up electrons. I think this must be the case ...
0
votes
0answers
3 views

Propagation error for a third grade equation

I am trying to find the value for the roots$\pm$error for a set of experimental data. The function that fit the best is $$\epsilon(t)=a+bt+ct^2+dt^3.$$ Which is the best way to calculate the roots ...
0
votes
0answers
5 views

How is a change in capacitance detected in a touch-screen?

So the screen has lines of conductors horizontally and vertically, seperated by a dielectric, and thus forming a grid of capacitators where the ones in one "row" are in parallell on the one side, and ...
0
votes
0answers
3 views

Wormhole Construction & ~ “Jump Conditions”

Throughout the literature Wormholes are typically constructed by "Minkowski" or "Schwarzschild Surgery" (see e.g. Visser, Lorentzian Wormholes...), i.e. under quite simple and/or highly symmetric ...
0
votes
1answer
6 views

Calculate responsivity of a pyroelectric detector

I try to calculate the responsivity of a pyroelectric detector. My calculation is based on this equation: $R_{v} = \alpha \tau_{F} \frac{p}{c^{'}_{P}d_{P}}R_{G/fb}\frac{\omega ...
0
votes
0answers
5 views

Fierz identity for chiral fermions

First of all I define the convention I use. The matrices $\bar{\sigma}^\mu$ I will use are $\{ Id, \sigma^i \}$ where $\sigma^i$ are the Pauli matrices and $Id$ is the 2x2 identity matrix. I will use ...
1
vote
0answers
6 views

Spinning top fixed point

I have seen many explanations about the movement of a spinning top. The explanations were in a varied level, from basic newtonian mechanics to Lagrangian formalism. But I do not understand why some ...
1
vote
2answers
11 views

quantum field theory peskin textbook page 212

the Peskin's textbook chapter 7 Radiative Corrections: some formal developments (page 212 second paragraph), he describes two-point function and choose these states to be eigenstates of the full ...
0
votes
0answers
4 views

Is nanoparticle a Bose einstein Condensate

I was reading about nanopartilces(NPs) and their properties. At several places I have read that NPs act as coherent body. I wonder if the Nps can be treated as Bose Einstein condensate (BEC) as ...
-1
votes
0answers
9 views

What is the speed of transferring of energy in an inelastic solid?

Assuming that there is an inelastic, very low mass, very long, solid rod which is 150 million km long. This distance requires approximately 8.333 minutes for light to travel. If I apply a force at one ...
0
votes
0answers
15 views

Why is the frame dragging effect trillions times as strong around a spinning superconducter?

It´s a bit of a forgotten experiment, but why measured Tajmar and his team a frame dragging effect in the surrounding space of a spinning niobium superconductor, that was even measurable in the lab? ...
0
votes
1answer
17 views

Why is $\sqrt{v_1+v_2+\ldots} =246$ GeV in multi-Higgs models?

Where does the condition come from that in models with several electroweak breaking doublets the square root of the squared sum of the VEVs should yield $246$ GeV?
-1
votes
1answer
15 views

What is the electric field at the midpoint of the hypotenuse of a triangle?

Given, AB = BC = a and Charges at A, B and C are +q, +2q and +q respectively. Found this problem in a textbook. I did it this way : Charges at A and C will have no effect at this point since ...
0
votes
0answers
10 views

How much of fusion energy is positron-electron annihilation?

Stellar fusion involves protons becoming neutrons, which means ejecting a positron. Positrons annihilate electrons. This must deliver some energy in stellar fusion. But how much of the energy from ...
0
votes
0answers
19 views

How do things accelerate if every time they accelerate they get accelerated in the opposite direction?

Let's say that I have a book infront of me. I push it and it accelerates. According to Newton's third law I would have experienced the same force. But if I experience the same force in the opposite ...
5
votes
1answer
25 views

In quantum optics if you measure the energy of a thermal state does it collapse to a Fock state (Photon number state)?

As I understand it a thermal state is a state of light such that the light is in a superposition of many Fock states (Photon number states) with the probability of the light being found in a ...
0
votes
2answers
26 views
0
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0answers
7 views

The radiation intensity considering dipole, quadrupole and magnetic dipole parts

In page 204 and page 205 of the book "The Classical Theory of Fields" written by Landau and Lifshitz, there is this sentence In averaging the square of the magnetic field, all the cross-products ...
0
votes
0answers
7 views

The density parameter consistency relations in cosmology?

Hopefully this is an easy one. I've been asked to derive something using something referred to as the density parameter consistency relations. I'm not to sure what these are referring to exactly? ...
2
votes
2answers
31 views

Do quark charges repel one another?

Positive electrical charges repel other positive charges, and negatives repel negatives. But does that happen for quarks, too? I never saw mention of it, but if so, that would mean the up quarks in a ...
1
vote
0answers
19 views

Numerically integrate equations of motion with noise

Consider the equations of motion $$\begin{cases} \dot{x}(t) & = v(t) \\ \dot{v}(t) & = -\frac{\lambda}{m} v(t) + \frac{1}{m}F^{c}(x(t)) = a(x(t), v(t)) \end{cases},$$ where $x$ is the ...
-2
votes
0answers
17 views

There is a hollow object where will the charges reside? Inside the balloon or on the surface of it? [duplicate]

There is a hollow object (for example an inflated balloon.it is charged. where will the charges reside? Inside the balloon or on the surface of it?
0
votes
0answers
7 views

Convert Stokes vector to Jones Vector

I have a similar question to Converting Stokes Parameters to Jones Vector I want to convert data from a polarimeter that is given in (x,y,z) on the Poincare sphere into a Jones vector. Is it ...
-2
votes
0answers
33 views

Is this correct? [on hold]

Yes, these are hands. No, i'm not good at drawing If the muscles of one hand are pushing with $100N$ and the other with $200N$, at the contact, due to Newton's third law, the force acting on both ...
2
votes
1answer
27 views

Can a symmetry breaking VEV lie far above the “symmetry breaking scale?”

The scale where some symmetry gets broken can be computed using the renormalization group equations for the gauge couplings. If there is only one Higgs VEV responsible for some breaking, can this VEV ...
0
votes
0answers
27 views

Hurricane Emily

I need some help with my homework problem. In 1993 the radius of Hurricane Emily was about $350$ km. The wind speed near the center ("eye") of the hurricane, whose radius was about 30 km, reached ...
0
votes
0answers
28 views

The wavelength of EMR reaching an orbiting ship at .99 c

In this answer John Rennie says that, if a ship is orbiting the Earth at .99 c: .. observer on the Earth sees time moving slowly for the astronaut, while the astronaut sees time moving fast for ...
1
vote
0answers
18 views

Rainbow Black Hole

In the photon sphere of a black hole the photons are being trapped in orbit, pulled in and trajectories changed. Should we see color of the entire spectrum in the photon sphere? That a black hole ...
0
votes
1answer
26 views

Magnetic force on a charged particle doesn't affect total energy

So there's this sentence in a book I am reading. It states "When a charged particle is placed within a magnetic field, despite the magnetic force acting on the particle, there will be no change in the ...
1
vote
0answers
12 views

What are the Higgs masses for $SU(2) \times U(1)$ goes to $U(1)$ symmetry breaking with a complex triplet?

Consider an $SU(2)\times U(1)_Y\rightarrow U(1)_{EM}$ theory that is broken via a complex triplet with hypercharge 2. The potential is of the form \begin{align} V(\Phi) = -m^2\Phi^\dagger\Phi + ...
0
votes
0answers
18 views

Why can an electric chargeless Z-particle decay in three photons?

The Z-particle that is supposed to convey the weak force has no electrical charge. So how is it possible the particle can decay in three photons. Because the weak and e.m. force are more or less ...
0
votes
1answer
25 views

Principle of capacitor

It is said that second conductor reduces the potential of fist conductor and hence increases charge taking ability of first conductor My confusion... As per my limited knowledge it is electric ...
0
votes
0answers
17 views

thermodynamics tables

Steam is heated from 10 kPa and 50°C to 550 kPa and 500°C. Calculate the change in entropy: 1) If the steam is not considered an ideal gas 2) Discuss if it is appropriate to consider steam an ideal ...
0
votes
0answers
12 views

Contact Angle In Capillary

One Professor recently told me that in an insufficient length capillary, the contact angle doesn't change, its an inherent property which does not change. If the edges of capillary are extremely sharp ...
0
votes
1answer
9 views

Conservation of $C$-Parity and $P$-parity

Under what situations are $C$-Parity $C=(-1)^{L+S}$ and/or $P$-parity $P=-(-1)^L$ conserved? ( $L$ here is the relative angular momentum and S is the total intrinsic spin). It would make sense that ...
5
votes
3answers
643 views

Advantages of Lagrangian Mechanics over Newtonian Mechanics

Here, I'm going to pose a very serious list of doubts I have on Lagrangian Mechanics. Can we learn Lagrangian Mechanics without studying Newtonian Mechanics? Does Lagrangian help in solving problems ...
2
votes
1answer
38 views

Why does it matter which way I put a battery into an electronic device?

If I take a battery, some wire, and a light bulb and hook them all in a circuit that would create a current and light the bulb. If I turned the battery around so the terminals were switched then I ...
2
votes
1answer
39 views

How to understand the idea of functional renormalization group?

I have been looking at how to use the functional RG method in many-body systems, but I don't quiet get the idea of it, it look different from Wilson's RG approach (eg. why shall we integrate out the ...
0
votes
0answers
11 views

Does the irradience on a surface change as the length scale of the surface patch approaches the wavelength of the incident light? [on hold]

Imagine an ideal, square, surface patch with sides of length l and area a that is a perfect absorber. Imagine this patch is being illuminated by a monochromatic plane wave. The irradient power on ...
1
vote
1answer
30 views

What do different frequencies in astrophysics data file mean?

I have a data file, with the first part looking like this. ...
0
votes
0answers
32 views

What would happen if a black hole merged with a white hole of the same size?

I learned about white holes a while back, this was the first question that came to mind.
0
votes
0answers
66 views

Could renormalization cutoffs be adjusted to explain absolutely any physical observation?

It seems like absolutely any observation can be expalined mathematically with no change to quantum theory except particular adjustments to renormalization cutoffs. Is this true? Example: Let there ...
-2
votes
0answers
18 views

Tsunami Modelling

In the coastal zone and seas, having relative small scales (up to 1000 km), the model of plane Earth with no rotation is applied $$ \frac{\partial M}{\partial t}+\frac{\partial M^2}{\partial ...
0
votes
1answer
20 views

Heisenberg Representation of Quantum Computers explain observable transformations

The Heisenberg Representation of Quantum Computers (Daniel Gottesman) http://arxiv.org/abs/quant-ph/9807006 Suppose we have a quantum computer in the state $|\psi\rangle$, and we apply the ...
0
votes
0answers
30 views

Is there a substitute for point particles other than strings?

In the Standard Model, QFT makes use of point particles. But are there models of elementary particles that are not pointlike? And I don´t mean the objects in string theory/M-theory.
0
votes
0answers
15 views

Topics to learn, or books to be read for understanding physics goals of LHCb, and how LHCb detectors work

I would like to understand the physics behind the LHC experiment. I have some basic knowledge of modern physics, but have no knowledge of mesons, bosons, their decays and so on. I would like to know ...
0
votes
0answers
27 views

Photon Propagator in QFT

Please forgive my temporary split-brain, but I'm a little thrown off by something when considering units at the moment. In QED (depending on the guage), the photon propogator is written as ...
0
votes
1answer
83 views

Breaking Newton's 3rd Law?

I am having trouble explaining how the following experiment actually works, but it does.? Place a neodymium magnet on a piece of Styrofoam and a test tube of water next to it on the same piece of ...
0
votes
0answers
15 views

non linear friction tsunami modelling [duplicate]

Deriving the following equation $$ \frac{∂u}{∂t}+u\frac{∂u}{∂x}+g\frac{∂η}{∂x}=\frac{−k}{2h(x)}u|u| $$ $$ \frac{∂η}{∂t}+\frac{∂[(h(x)+η)u}{∂x}=0 $$ equation (13) at ...

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