Strange Definition and 588 Threads

:smile::smile::smile::smile:Have you ever observe in night a source ( spherical) emitting light in strange fashion. If not then observe today. I saw that it was more towards the corner making plus sign or cross sign which can be seen through our eyes . Is there is something which is attracting...

I have seen it the claimed that the Einstein-Hilbert action can be written in terms of a tetrad ##e_{\mu} \, ^a## as \begin{align} S &= \int d^n x \, e R(e_{\mu} \, ^a, \omega_{\mu a} \, ^b (e)) \\ &= \int d^n x \, e (T_{ca} \, ^a T^{cb} \, _{b} - \frac{1}{2} T_{ab \ c} T^{ac \ b} -...

Hi, I really hope someone here can help. I'm a nurse and not in the computer field (so I might be doing something dumb). We have a really old fortran system that we keep old history on. I'm trying to move the program onto a new computer. Its been a mission to do, but I've got through most...

This is probably the weirdest chemical reaction you'll ever see.

I have a strange problem. I am an active member of AudioKarma forum. 3 weeks ago, all of a sudden, the site is very slow in responding, when I try to navigate in the site, I get kick back to the main page instead of going into the thread I click. It's very slow, also, uploading failed or very...

It's early evening here (Ireland). The Sun is definitely set, and there is a bright half Moon. However there are no stars or planets visible at all, anywhere in the sky. There is no cloud, at least nothing substantial, the Moon is perfectly bright, no sign of cloud in that part. There are low...

Homework Statement Solving an exercise I found myself with this problem: the solution ##c## needs to verify both ##\sum_{k=1}^c n\lambda^k\frac{e^{n\lambda}}{k!}\leq \alpha## and ##1-\sum_{k=1}^{c+1} n\lambda^k\frac{e^{n\lambda}}{k!}\geq \alpha##. Can an equation like this be solved for c...

What is going on? Anyone else think all of this is very strange (Existence, The Universe, Everything) I mean what the hell is going on why are we here and why are we so dominant over other species on this earth? It's as if we are playing a video game and have cheat codes. Also a lot of video...

https://arstechnica.com/the-multiverse/2017/07/read-some-seriously-strange-time-travel-stories-from-sci-fis-modern-masters/

I have analysed some roulette spins with sony vegas in order to get the time for each turn of the ball. It is supposed that if the time that takes for the ball to complete a turn is higher, it means that its velocity is faster and thus the time at which it will fall off from the rim will be...

Hi. For a state of nitrogen in which temperature is higher than the critical temperature the state is presented on a different curve. I do not remember any curve for superheated region. Source: Introduction to Engineering Thermodynamics by Sonntag/Borgnakke. Thank you.

Hello Forum, I've gone about graphing the below equation by inserting values in for y and then solving for x: y(x-1)=x2-1 For instance, I say y=3 and then solve: 3(x-1)=x2-1 3x-3=x2-1 3x=x2-1+3 3x=x2+2 0=x2-3x+2 0=(x-1)(x-2) Thus x = 1 and 2 and so I plot co-ordinates (1,3)...

When I enter my usual sites, click somewhere on them strange advertisments are making themselves appear, opening a new window of the browser. How can I determine what program or add-on causing this problem? Thank you.

Hi When I was writting my thesis I found in an article, published in International Journal of Heat and Mass Transfer, an unit of mass flow rate G - kg/(m^2*s). Isn´t it wrong? I think that the unit of mass flow rate is kg/s. Would you mind helping me to figure it out? Thanks.

I encountered this in http://calcchat.com/book/Calculus-10e/8/4/7/ How come the above expression equals the below? What I know it should be 4 ln(x/(4+sqrt(16-x^2))) which means the -1 becomes the power of that thing inside ln. Please help me. I really don't get it.

Hello and I would like to thank you for your space in this website I'm from Greece and i have exams in next days I need some help with an exercise that I can not solve! There is a probability density function with the following type : P(Y=y/X=x)=f(y,x)= {n \choose y}* {x}^{y} *...

So at 5:20 it is explained that many of the quarks are converted to strange quarks and this is a away of going around the pauli exlusion principle inside of a quark star. So does this mean it's like a Bose Einstien Condensate? The Bose Einstein Condensate is very cold though.

This question is regarding classical black holes. So inside the event horizon, spacetime behaves strangely. Space is now one dimensional and only in the forward direction(that is, into the singularity) and time of events is preceived as forward and backwards since light from a source comes...

I wonder what would the angular momentum vector look like for these gears. As it rotates, there is no clear direction on where the angular momentum vector is pointing. This object is symmetric. Here's the video about these.

could anyone explain me how is it possible to charge your phone wireless, like this video link?

I want to be a quantum physicist as a career because i absolutely love the mystery behind certain principles in quantum physics. Especially things like the quantum eraser experiment. I am wondering if there is a reason that quantum mechanics has very weird principles that seem to defy logic...

Hi I am a new member, I felt compelled to find a forum to talk about what i have been watching in the night sky. I have been watching the sky most evening now for the last couple of weeks, since one Saturday evening around 12pm I noticed what at first sight looked like a plane siting in the...

How many have watched the marvel movie Doctor Strange here? Can you consider the shifting buildings as what happens when the branches in Many Worlds occur or perceivable by the movie sorcerers? It explains the powers of Doctor Strange is tapped from Many Worlds.

A little complicated and interesting story, I will get down to the point: I need a number of substances that cause skin rashes/skin redness or overall has a bad reaction to human skin. This is all for research purposes for natural skin products me and a group of friends are developing.

Homework Statement 7. A boy drags his 60.0-N sled at constant speed up a 15.0° hill. He does so by pulling with a 25.0-N force on a rope attached to the sled. If the rope is inclined at 35.0° to the horizontal, (a) What is the coefficient of kinetic friction between sled and snow? (b) At the...

I was looking for a derivation of E=(2kλ)/r for an infinite line of charge. I understood that you need to use Gauss's Law and a cylinder around the line. When looked it up, I found this: http://www.vizitsolutions.com/portfolio/gausslaw/lineCharge.html He starts out with ∫E⋅dA=4πq. I have never...

Hi everyone, I'm trying to study reflection on the rear side of an optical device. I wrote a transfer-matrix code in MATLAB to compute the reflectance. I checked my code by comparing some basic cases with other kind of optical simulations (FTDT with Lumerical). When the incident medium is Air...

In a thought experiment, there is a spin-0 source emitting particles. (I suppose you already know what is that experiment.) Two observers in opposite sides along the same axis measure opposite spin components. If one observer measure, say, spin up, then the second observer will certainly measure...

Homework Statement I'm trying to write a program to calculate Newtons of impact force from a fall given the weight, general size, shape, and density of an object. I want to take air resistance into account. I also want to take the density of the thing the object falls on into account. I am...

I live about 1/4 mile from the Interstate Highway. I am far enough away the traffic can not be heard until the sun is very low on the horizon. Every even for about 1 hour when the sun is very low it sounds like the interstate traffic is in my back yard. It is so loud it is just like standing...

Hi ladies and gents! I'm new to the physics community and completely useless in the subject area, however I am extremely interested in physics. After turning off the television just now I noticed something odd. There is a big mirror behind the bed, and the television is on the wall in front...

SO fun story, I'm working on a client server dealio! The flow of operations should be: Server listens on port 9999 Client connects to port 9999 Server tells Client to connect to new port # (to allow for more connections) Server launches a thread and listens on new port # Client disconnects...

1. Imagine a big river with water flowing constant velocity , assume there is a whirlpool at center as shown in the figure. 2. Because of the magnus force the whirlpool should move towards left or right towards river bank depending on the spin, but it does't happens it just stays fine in its...

First of all i will post a picture of it ... you can find it ... somewhere sorry this is my first post :I I photographed our television with the flash on in order to recreate a strange patter i saw when looking at the suns reflection in the screen.(with my eyes it's not just the camera) You can...

I read and loved the comic as a kid. Can't wait for this one on the big screen. The only thing better would be to get my Dr. Strange comic collection back that my mom tossed while I was in the Navy.:H:cry:

Hi, So I was just vacuum cleaning the carpet in my room , I have wooden floor and the overall air is rather dry and warm.Normally I get static electricity buildup when vacuuming because the small dust particles that go through the cleaners pipe build up charge on the plastic pipe , I assume...

Homework Statement The problem asks for a single triple integral (the integrand may be a sum but there must be a single definition for the bounds of the integral) representing the volume (in the first octant) of the shell defined by a sphere of radius 2 centered around the origin and a sphere...

I'm watching Susskind's Classical Mech. YouTube lecture series and am really confused about something he's doing where otherwise I've followed everything up until this point without a problem. In Lecture 3 he's dealing with the Euler-Lagrange equation applied to minimizing the distance between...

I was waiting in a old courthouse hallway with alternating white marble and black granite tiles, when I noticed some interesting spirals etched on several of the black granite tiles. No cameras so no picture but I can describe it fairly simply, I think, since I have basic understanding of the...

I was offered an Ostrich meal but i could not bring my self to order it, yet when abroad i ate several things with no idea what they were:eek:

I'm writing a piece of fiction that, if my understanding of the subject is correct, will include a bit of chemistry knowledge. (In explaining my question, I'm going to spell out some obvious things. I'm terrible at math, and hence even worse at chemistry) For example: Atomic weight is...

My phone adapter makes a screeching sound when switched on, but not too loud to be audible to everybody. I know there are eddies within the transformer, but other adapters do not seem to be noisy. What is that?

ok so I was creating a connection today and used a 5 v led on a 1.5 v battery. Battery was in a case from radioshack and had insulated leads, full of twisted micro wire. Since there was no way to crimp it or strip the wire without me ruining the twists, I just bundled it to some non twisted wire...

Homework Statement *This is not my whole problem, I am only stuck on how to interpret one part of the question. Put simply, I want to find the expression for the density of energy levels in a given energy band per unit volume (in some crystal structure). Say I have an infinitesimal interval of...

Homework Statement I need to find the Fourier series for f(x)=|x|^3. Homework Equations f(x)=|x|^3 A_n=\frac{2}{L}\int_{0}^{L}|x|^3cos{\frac{n\pi x}{L}}dx \int_{0}^{L}x|x|sin{\frac{n\pi x}{L}}dx The Attempt at a Solution Since it is an even function I know that it will be a cosine series and...

I ran across this integral while reading Ashcroft and Mermin's solid state physics book... ∫Θ(f - f(t) )dt = t_max - t_min Where Θ is the heaviside step function and the integral runs from 0 to infinity. Does anyone have any idea how this integral makes sense?

A dc brushed motor with a commutator, the stator isn't fixed to anything and is left freely on a desk for example, now apllying power the rotor starts to turn, if I take the rotor and hold it with hand the stator now starts to turn around , I assume this happens because the stator poles and...

Hello, In my understanding, decay of quarks should give leptons of the same generation as the quark has, like in a basic way, neutron decaying into proton and an electron. Because of this I have trouble understanding why the strange quark turns directy into up quark, an electron and an electron...

Hi! I have just performed some experiments with my phones accelerometer, and plotted the acceleration as a function of time from the raw data. The experiments I did was: jumping down from a chair jumping from the floor and up let the device fall toward a bed When I analyze the graphs, I think...

I have a question about a seemingly illogical and strange aspect of multiplication and unit conversion that I have never noticed until now. It concerns the issue of finding the area of a square/rectangle when the length and width are expressed as decimals/fractions. Ordinarily, when you find...