Stable Definition and 303 Threads

not asking about neutron stars, where gravity holds neutrons together, rather would the strong force hold individual neutrons together in a solid mass, preventing their decay if one could somehow put them together in a lab?

I am struggling with Hamiltonian formulation of classical mechanics. I think I have grasped the idea of canonical transformations, including the idea of angle-action variables and invariant tori in phase space. Still, few points seem to elude my understanding... Let's talk about a particle...

V = ? m/s V = D/T V = Square root (6.67 * 10^-11)(m)/r

I was wondering if we could have an object made up of only electrons. Normally, that wouldn't be possible because electrons repel each other. However, this repulsion can be overcome using gravity. So my question is, how many electrons would you need to have their gravitational attraction...

Say one was to create an artificial stable isotope of Promethium as it has predicted applicable properties. What would it’s number have to be? I know Promethium-147 is semi-stable.

Hi all , please refer to the picture regarding my working. please correct me if My working is wrong. I am quite confused about the positive and negative sign in equation

As an example specifically, sputtering is used for putting coatings onto razor blades. People are told to not wipe the blade for cleaning. So does the coating have any resistance like in case a user gives a single pull through something like a cork or a styrofoam cup, to remove any accumulated...

Hi, All cosmological models with a non-zero cosmological constant will approach a de Sitter universe in the far future. In theory this can means that the most basic group of particle physics should be the de Sitter rather than Poincaré. Mass is a Casmir operator of the Poincare but not of the...

I wonder if you could help me with both I'm stuck, I know that in order to see if the electrostatic equilibrium is stable or not at the center of the ring , the potential energy has to be minimum there. I was going to use Laplace eq. but it allows neither minimum nor maximum. Then I also...

Summary says it all, I think. If you just want to link me to a bunch of papers, that's fine by me. All I was able to find out on my own is that mouser and digikey have a lot of off-the-shelf voltage references they want to sell me that get about order of ##10^4## SNR at those timescales. SNR...

Homework Statement:: The solution to the KG equation is assumed to take the form$$\Phi = \sum_{l=0}^{\infty} \sum_{m=-l}^{l} \frac{1}{r} \phi_{lm}(t,r) Y_{lm}(\theta, \phi)$$ Relevant Equations:: N/A To first show that $$\left[ \frac{\partial^2}{\partial t^2} - \frac{d^2}{dr_*^2} +...

I need to create a 5 V stable DC supply out of 6 V AC from a transformer. By "stable", I mean that I do not want the ripples in the voltage that one gets from the output of a full-wave bridge rectifier. I have to feed this to two ATmega 8A μCs. I am going to create the following circuit: 6 V...

Just quick question: Could you put space stations (or even other small planets) at any aribitrary orbit or any radius in between Jupiter and Mars? Or, if something attempted to do so, would the orbit be unstable, and the object drift to either Mars or Jupiter? I was reading about Lagrange...

Hey everyone! So I have attempted this Q which is shown below I had a go at all the parts and I think they are right but I'm not so sure on what answer to give for c)iii, I mentioned about the ratio of protons to neutrons but I'm not sure if that is necessary over here? Any help would be...

Hi, I am reading the following paper: Toward Practical Secure Stable Matching: https://encrypto.de/papers/RSSSK17.pdf. According to the paper: and at other place: Somebody please provide me an example for this model i.e reducing from multiparty data into 2-party data. Zulfi.

I was discussing a problem related to Einstein's universe model. As we all know its an unstable equilibrium. So a small fluctuation in the density would result in an either expanding or contracting universe. However, I read that "There are static and stable solutions in Newtonian gravity...

John Maynard Smith: The Evolutionary Stable Strategy.To noted evolutionary biologist John Maynard Smith, life is essentially about information -- how information is stored, passed on, and used by organisms as they live and reproduce. "And evolutionary theory is about how that information got...

If you divide using your imagination a particle into two halfs(or n, n-th parts) you'll notice that cherge tends to expand and mass tends to colapse into singularity.It's more then sure that there are some inner forces from within the particle and they have to be balanced.One way to do it is to...

Refer to Below Images, one and two:(A) and (B) are horizontal rings of iron [refer to image two], copper wire is wound around each ring, as shown in the vertical cross section [image one], to form electromagnets. The two currents run in opposite directions, so as to create opposing magnetic...

I'll give a quick synopsis for any who aren't already aware of the details, so that all may follow the thread if interested. A quark star is also known as a strange star, strange matter star, quark nugget, or neutron star. I avoided the phrase neutron star for a good reason: the core that I'm...

Hi, I have a couple of questions regarding radioactivity.[1] The isotope of strontium, Sr [Z=38, A=90], decays by Beta emisson and forms the radioactive isotope of yitrium, Y [Z=39, A=90].The half-life of Sr [Z=38, A=90] is 17.8 years and the half-life of Y [Z=39, A=90] is 64 hours.Calculate the...

I've read that the phenomenal red area on Jupiter is visible from Earth every time (no rotate as rest of Jupeter's atmosphere). Is this fact?The second question is about its stability. What is the true cause of the stability? This is only stable atmospheric event in whole known universe...Third...

Today I've learned that the number of nucleons in a stable nucleus is always less than 83. Why could't I put 85 neutrons together to form a stable nucleus.Since they only attract each other I don't see why it can't be stable

Why does a hydrogen filled flying airship burst into flames from a spark? Why is helium with its one more extra surrounding subatomic orbiting particle resistant to the spark explosion reaction? Do the two orbiting sub atomic particles around a helium atom make it stable somehow immune to the...

Refer to Below Images, one and two:(A) and (B) are horizontal rings of iron [refer to image two], copper wire is wound around each ring, as shown in the vertical cross section [image one], to form electromagnets. The two currents run in opposite directions, so as to create opposing magnetic...

In Thailand university professors become an unstable job due to a new policy. There's literally zero job security even if you get tenured (become associate ,assistant profs) you'll still get sacked by the authorities if you don't conform to them. Little to No retirement pensions. Some professors...

Is it possible to have a configuration of two classical positive charges and two classical negative charges that will remain fairly stable (or at least metastable), if started off in some well-chosen initial condition? For example, we might want to eliminate radiation by having the electrons...

I tried by taking the derivative of the potential to find the critic points and the I took the second derivative to find which of those points are minimum points. I found that the point is ##x=- a##. I don't understand how to calculate the period, since I haven't seen anything about the harmonic...

Why is Uranium-236 less stable than Uranium-235 and Uranium-238?

Homework Statement A) By examining the effective potential energy find the radius at which a planet with angular momentum L can orbit the sun in a circular orbit with fixed r (I have done this already) B) Show that the orbit is stable in the sense that a small radial nudge will cause only...

Homework Statement y(t) = x(1-5t) Homework Equations noneThe Attempt at a Solution well I've never looked at the stability of a signal which has a time scale and shift. My guess is that it is stable as anything I can provide as input will output a bounded signal. Ex: if x(t) is u(t) then...

I´ve seen it asserted at the general physics forum that melting point of amorphous substance is "always" lower than the "melting point" of corresponding crystal. Also, amorphous solids are often described as metastable against crystallization. Does it necessarily apply to all amorphous solids...

I recently learned that Bismuth is actually radioactive with its longest lived isotope having a half-life of about 20 quintillion years. (For source, see: https://www.nature.com/articles/nature01541) As a very basic question, what determines whether an element/isotope will be radioactive? Is...

Homework Statement [/B] Which is more stable cyclobutane or cycloheptane? Homework Equations [/B] [(n-2)180)]/n = angle The Attempt at a Solution [/B] So the closer the angle is to 109.5 the more stable (except for cyclopentane vs cyclohexane). n = number of carbons [(7-2)180)]/7 = 128.57...

Imagine a steel I-girder lifted by a single wire rope. If the rope is not perfectly centered along the girder length, the girder will rotate about a horizontal latitudinal axis through its centroid. Imagine a girder pair lifted by two wire ropes, with one rope on each side of the girder...

What's the difference between neutral and stable? As an example of H2. Here two H atoms combine and make an H2 molecule. Now two H atoms are neutral as they have the same number of protons and electrons. So the H2 molecule is neutral. on the other hand. Two H atoms combine through a covalent...

Homework Statement A circular hoop of radius R rotates with angular frequency ω about a vertical axis coincident with its diameter. A bead of mass m slides frictionlessly under gravity on the hoop. Let θ be the bead’s angular position relative to the vertical (so that θ = 0 corresponds to the...

Hello Everybody! My name is TanX and I got a figure in my mind while studting concepts related to Vertical Circular Motion. I tried finding a solution to it (i.e) I tried finding the condition for movement of the particle in the figure that had come in my mind... Homework Statement So here is...

I am in the process of writing a lecture out for my Graduate modeling class I teach. I normally don't write lectures out in LaTex or use PDF's because I write on the dry erase board, but if anyone is interested I wouldn't mind spending the time to type out some notes on the topic. The topic...

https://futurism.com/stable-plasma-ring-created-open-air-first-time-ever/

Homework Statement I'm having difficulty knowing how to determine if a given differential equation represents a stable, neutrally stable, or an unstable system. I was given a hint to focus on the homogeneous solution, so is the particular solution not important for determining if the...

Hello, I have been wondering if it is possible to create and store stable ions, is it? Thanks.

i really need help about shunt and series resistances i just want to know if they are constant or variable ? if they are variable what make them increase or decrease?

I was looking at this neat graph of all the isotopes and which ones are stable and how they decay: https://upload.wikimedia.org/wikipedia/commons/thumb/c/c4/Table_isotopes_en.svg/715px-Table_isotopes_en.svg.png The black squares represent stable isotopes, and columns that have no such black...

Does GR allow for photons to be in a stable orbit around a massive body?

Hi there. I was trying to solve the time dependent diffusion equation in only one dimension. I derived a explicit scheme using a finite difference in the time variable. The equation I am trying to solve is: ##\displaystyle \frac{1}{c} \frac{\partial \phi(x,t)}{\partial t} -...

in a universe without the higgs field fermions would be massless in absence of the higgs field, would second and third generation fermions such as muon tau top quarks etc be stable? how to distinguish between a massless electron muon and a tau in a universe without the higgs field, same for...

Homework Statement The controller K(s) = Kp, determine the range of Kp over which the closed loop system is stable. Homework Equations I found the transfer function of system = Y(s)/V(s)=Kp/(1.5s^2 + 2.5s - 1 + Kp) The Attempt at a Solution So i know (1.5s^2 + 2.5s - 1 + Kp) is the...

Hi, I'm not a scientist or engineer,, I'm actually an artist, with severely insufficient knowledge in chemistry . I also don't work for a big company that's funding my project, I'm paying for everything myself. I trying to make a water in oil micro-emulsion at home that does no require any...

Homework Statement [/B] Give examples of fixed points of vector fields and maps that are stable in the linear approximation but are nonlinearly unstable Homework EquationsThe Attempt at a Solution [/B] I was able to find an example in a vector field that, when the Jacobian is found and the...