Zero Definition and 1000 Threads

I have been attempting to calculate optimal zero for my H&R 30-30. 190g 170g 160g 150g These links are the optimal zeros for my rifle based on each of the four grain weights available to fire thru the rifle. I don't want to have to re-zero my rifle every time I switch between ammo types so I...

Hi people, It's been years I wanted to post this question here. I would like to build a zero knowledge proof that a given chess position contains at least one checkmate. I know that anything provable admits a zero k proof. I know about...

I stumbled over a datasheet of an old pentode where it says, in the english translation: I thought, wow, I am not sure if I wouldn't have written Ug3=0V instead. I am a theoretician in physics but work more as an engineer and teacher. What happens inside of me seems to be the following: The...

I want to ask about the direction in which ##D_v## is zero at point (1, 2, 1) My attempt: $$w_x=yz+\frac{1}{x}$$ $$w_y=xz+\frac{1}{y}$$ $$w_z=xy+\frac{1}{z}$$ At point (1, 2, 1), the ##\nabla w=<3, \frac{3}{2}, 3>## $$D_v w=0$$ $$\nabla w \cdot v=0$$ $$ \begin{pmatrix} 3 \\ \frac{3}{2} \\ 3...

In the context of the mappings of a set S into itself, when S is not number system with a zero, what is the customary definition for "zero mapping"? ( ChatGPT says that its a mapping that maps each element of S to some single element of S , i.e. maps all elements to some constant. )

In another question I posted on here, I asked about a hypothetical roulette wheel with an infinite amount of spaces. Each number has a one-in-infinity chance of being selected, yet each time the wheel is spun, one number wins those odds. My initial question was how this was possible, and I had...

So the confusion here is that division by zero is often said to be undefined. So whereas, the point (0,0) certainly appears in the set of values where x=y, does the point (0,0) appear in the set of values where 1=y/x. Why or why not? In other words are the set of points where x=y the same as...

I keep getting particle lost error even though there were no hole in the lattice. Can someone identify any mistake in my code?

Hi everyone, My plan is defining a surface source on a cylindrical object (cylindrical surface+top end+bottom end) and I am interested in what happens outside the cylindrical body. To avoid distortions of particles starting on the surface, directed inwards and emerging on the other side of the...

A division by zero is a mathematical oddity, , if a computer or calculator etc performs a 1\0 they would crash, the OS prevents the execution, and displays ERROR or UNDEFINED, , , some versions of windows calculator display positive or negative infinity, , try it Any ideas on this ?

I simply just wrote down the definition of ##\Gamma'^a_{bc}##, and inserted the transformations of ##g'^{ad}##, ##g'_{dc,b}##, and the like terms. After some rearranging and cancelling out, $$\Gamma'^a_{bc}=\frac{\partial x'^a}{\partial x^e}\frac{\partial x^f}{\partial x'^b}\frac{\partial...

Can we all agree that electrons still move at absolute zero?

The electric field strength at the center of a uniformly charged disk should be zero according to symmetry of concentric rings about the center, where each ring is contributing to the electric field at the center of the disk. For a thin ring of uniform charge distribution the formula is ##E =...

Can anyone explain to me why grounded means zero electric potential. I confuse what's the relation between infinite ground conducting plane and its electric potential (the method of images). I have a several question: 1. Why the conductor plane must be infinite, while in reality there's no...

For the problem attached, Why is the magnetic Flux not zero through the loop? Many thanks!

If F = 0 then a = 0. When the equation is written in the form F = m*a, it appears ok, that whatever the mass be, LHS and RHS of the equation are equal so no problem. But when the same equation is written in the form m = F/a, then m becomes undefined when F = 0 and a = 0. It occurs to me that...

Hello, so we have two potitions right, if we take ##\theta = 90## as the first position (i.e. both rods are flat) and then the second position at ##\theta = 0##. I totally understand the exercise, not difficult. The only issue I am having is the torsional spring... it says that it is uncoiled...

Relating to Stratus' thread in this forum, I'm trying to figure out initial velocity of a jump in zero g. Lets start in 1g. In one g, a person might be able to jump 1m. From this, using : v^2 = u^2 - 2as, we can calc his initial u as 4.45m/s. Is it a safe assumption that, were an astronaut to...

In chapter 2 of Dodelson’s modern cosmology book, it reads: “Implicit in this discussion will be the notion that the universe is smooth (none of the densities vary in space) and in equilibrium (the consequences of which will be explored in Section 2.3). In succeeding chapters, we will see that...

Are both integral on picture below equal zero? I think both are zero, area of zero section under function must be zero. If M=∞, b=∞ , what is reslut? Logically ∞/∞ will be 1..but...

How can we detect electrical effect of a static point charge at all? I think of a point charge like a sea urchin. With field lines going outwards in all directions (for +ve). So the vector pointing at me directly should be canceled perfectly by the vector going away from me. And so each line...

Theorem: Let ## X ## be a random variable. Then ## \lim_{s \to \infty} P( |X| \geq s ) =0 ## Proof from teacher assistant's notes: We'll show first that ## \lim_{s \to \infty} P( X \geq s ) =0 ## and ## \lim_{s \to \infty} P( X \leq -s ) =0 ##: Let ## (s_n)_{n=1}^\infty ## be a...

I just finished this book. Bravo. Paul Anderson is one of the masters. In this book, he tells the story of a spaceship traveling so close to light speed that it can traverse a galaxy in only a second shipboard perceived time. Of course, space travel and time travel are bountifully explored...

"the christoffel symbols are all zero at the origin of a local inertial frame" Why must it be at the origin? If it is not?Thanks!

Hi everyone I have the solutions for the problem. It makes sense except for one particular step. Why does the dot product of a and b equal zero? I thought this would only be the case if a and b were at right angles to each other. The solutions seem to be a general proof and should work for...

From calculating a few CG-coefficient tables, it occurred to me that when we add two angular mometa ##j_1=l## and ##j_2=1## (with ##l## whole integer), the resulting ##|j=l,m=0\rangle## state always has zero C-G coefficient with ##|j_1=l,j_2=1;m_1=0,m_2=0\rangle## component, i.e., ##\langle...

Greetings, Given an infinite universe or an infinite number of universes? - Regarding the location of an electron around an atom, is there a tiny volume in which finding the electron 100%? Or is there a possibility, no matter how remote, it might be found a meter away or a kilometer away? -...

On one side, if I have any finite value of s = the side of the original triangle of the Koch snowflake iteration, then the perimeter is infinite, so intuitively On the other hand, if I looked at the end result first and considered how it got there, then intuitively (Obviously at n=infinity and...

https://arxiv.org/abs/2207.02472 InAs-Al Hybrid Devices Passing the Topological Gap Protocol "We present measurements and simulations of semiconductor-superconductor heterostructure devices that are consistent with the observation of topological superconductivity and Majorana zero modes."...

I was wondering... imagine a large enclosed space sealed off in intergalactic space, filled with air at normal sea level pressure. I was further wondering with regard to a quadcopter's symmetrical x and y-axis and the fact of the thrust vector always being normal to the plane of the props, that...

I believe what I have to do to solve this problem is find the potential at each end face and then use the super position principle to find the net potential. So my boundary condition v and iv will give the potential at each respective position. Im just a bit confused about my boundary V...

Electric field is 0 in the center of a spherical conductor. At a point P (black dot), I do not understand how the electric field cancels and becomes 0. Electric field is in blue.

Homework Statement:: See attached Relevant Equations:: Ring Theory Trying to go through my undergraduate notes on Ring Theory ( in appreciation to my Professor who opened me up to the beautiful World of Math)...anyways see attached... I need some clarity on the zero divisor. I am aware that...

So for the transmissibility ratio equation, after doing a lot of questions when damping is zero and I have to take the square root of the denominator. Some questions take the positive root (1-r^2) while for other questions the solution takes the negative root (r^2-1). Can someone explain when we...

I'm studying Noether theorem.In the derivation process,I saw a equation:J=1+∂σ(δxσ),where J is the Jacobian,the second σ is superscript...Since δ has the property to commute with differentiation,why is ∂σ(δxσ) not equal to δ(∂σ(xσ))=δ (1+1+1+1) =δ (4) =0?

I'm having an exam soon so i want to make sure. Is the electric field here zero?? cause if i draw gauss surface covering both of them they should cancel out or am i wrong.

Figure shows a locus of the figure axis of a symmetrical top on a unit sphere such that ##\dot{\theta}=\dot{\psi}=0## at the upper bounding circle. Where ##{\theta}## is the polar angle and ##{\psi}## is the azimuthal angle. Suppose the figure axis is at the upper circle, since...

Hi! Given three voltages as follows; Q1 = 1C,Q2 = 1C,Q3 = 2C The distance a is 1m and b = 2m a) Find the values of the forces that are acting on Q2 I did that like this; $$ F_{12} = \frac{Q1*Q2}{4\pi\epsilon r^2} $$ $$ F_{32} = \frac{Q1*Q3}{4\pi\epsilon r^2} $$ The results are ...

Zero spin of Higgs boson? Is it really zero? Where is the spin (intrinsic angular momentum) of the Higgs boson on so small that we quantify it as having zero spin?I am aware of the reduced plank constant. But I we sure there is nothing in between the reduce Planck’s constant and the zero spin of...

I have to find the center manifold of the following system \begin{align} \dot{x}_1&=x_2 \\ \dot{x}_2&=-\frac{1}{2}x_1^2 \end{align} which has a critical point at ##x_0=\begin{bmatrix}0 & 0\end{bmatrix}##. Its linearization at that point is \begin{align} D\mathbf {f}(\mathbf {x_0}) =...

Earlier somebody was telling me about a type of object whose square is zero, and that apparently it has some applications to quantum theory (it wasn't explained very well...). Anyone know what he could have been talking about? And no, it was not "0"... :)

Quote from cern: "Just after the big bang, the Higgs field was zero, but as the universe cooled and the temperature fell below a critical value, the field grew spontaneously so that any particle interacting with it acquired a mass." Can it go back to zero? If anyone has a comment either way...

For a particle moving in a straight line, if the velocity is zero for a time interval, the acceleration is zero at any instant within the time interval. I am told the above statement is true. If I look at the equations v = dx/dt a = dv/dt It looks like if the velocity is zero for a time...

Consider a single atom (or particle) in a vacuum (without electric, magnetic or gravitational field) at near zero kelvin (i.e., no photons or particles striking it). I am curious if it will still have a magnetic dipole? If there still is (which I believe), had this been shown experimentally?

This problem comes from fluid dynamics where Kelvin circulation theorem states, that if density "rho" is a function of only pressure "p", then closed line integral of grad(p) / rho(p) equals zero. It seems so trivial, so that no one ever gives reason for this claim. When trying to solve it...

I made a new version of the falling cat video, with narration. It explains how cats turn around while having zero net angular momentum during the fall:

Does this mean that initially there will be emf induced on the coil at t = 0 s? Initially, at t = 0 s, the coil has not been rotated yet so based on Faraday's Law, there won't be any change in magnetic flux so why the value of emf is not zero at t = 0 s? Thanks

hello. I am trying to calculaty flux in bioshield cell but i get zero (f44, f54) and i can't figure out the reason please help :) txt file is a part of the code

So consider a subject system, a galaxy, with stars in it. This galaxy is passed by another object, the perturber. When the interaction is fast, we call this interaction a high-speed encounter. Now we consider that the interaction is really fast. This means that during the interaction, the...

The MCNP6.2 manual (page 3-37) says: "There are two nj values that can be used in the lattice array that have special meanings. A zero in the level-zero (real world) lattice means that the lattice element does not exist, making it possible, in effect, to specify a non-rectangular array." How...