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Posts posted by Dubbelosix


I agree, things like me and you only appear solid, because when objects tend to push together, electrostatic interactions push back. Gives things solidity on our level, but is really a composite system of much more complicated decohered systems owing their existence to entanglement and properties like the zeno effect in which evolution of wave functions do not happen.
Though a misnomer, I do believe in wave particle duality, I prefer to call it, wave particle complimentarity.
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4 minutes ago, Mordred said:
Take a waveform. A long sinusiodal wave has no determinant length.
A spike or excitation restores to ground state in a finite region. Thats your pointlike Compton wavelength where the pointlike property becomes meaningless beyond.
Mordred, the world is not just a construction of waves?
And a string is cited as a spatiallyextended object?
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4 minutes ago, Strange said:
https://www.fnal.gov/pub/today/archive/archive_2013/today130215_NutshellReadMore.html
so that’s all the elementary particles (including quarks, neutrinos and photons)
Different theory. And there is no evidence strings exist.
I am not a stringy person anyway, that wasn't my point. And whether or not its a different theory, it still matters, because it uses a rescaling principle to explain why point like interactions occur.
Yes I know people say this. But isn't this going off topic a bit. the question in this thread really should be about whether a nucleus rotates. No one disputes here a nucleus is composite and has real internal dynamics. My opinions about fundamental particles are pointless here.
Though, clearly the matter of real rotations for the nucleus has been pertinent to history since the literature indicates that a nonspherical nucleus can only do this. Which occurs frequently in nature as well.
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But it is still spatially extended. It is not a pointlike particle.
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In fact, I'll just leave you to give me a list, because I think quarks can be ruled out (they always form composite systems). Not sure really about the treatment of other fundamental particles, the Neutrino for instance is a strange object.
Just now, Mordred said:size isn't a particle property
Then how come strings are allowed to exist? Why do we make these assumptions and hold on to them concerning particles?
And why is it ignored in this discussion, that pointlike particles are directly related to the divergence problems, why doesn't that upset people like it troubles me?
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A top quark is certainly not pointlike, mind you they consist of composite systems anyway (you never find a free quark) and so can have a centre of mass. I am of course excluding massless radiation in this. What particles did you have in mind?
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7 minutes ago, swansont said:
Spin is not classical.
How many times are we going to go around on this?
There are two types of spin, classical and intrinsic. It's you who isn't getting it, the electron is the only pointlike particle because we cannot measure internal degree's of freedom and so of course, has an intrinsic spin. But this cannot be haphazardly applied to all particle systems, like you are doing.
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5 minutes ago, swansont said:
Saying it can rotate is not the same as saying the spin is associated with rotational KE.
It sure does.
Anything that classical rotates, requires energy.
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44 minutes ago, J.C.MacSwell said:
I am certainly far from anything close to expert on this, but it was my understanding that quantum spins were intrinsic. You seem to be saying that anything that is capable of having classic spin cannot have intrinsic (quantum to me, interchangeably) spin. Is that what you are saying or claiming? Is it accepted as correct?
What I am saying is that intrinsic spin was a concept that was deemed necessary for point like systems. To think that this idea intrinsic spin should be modelled to all systems, even though they may have internal degree's of freedom, is an unfounded assumption. There is evidence the nucleus rotates from the rotational bands as suggested by that poster and so would possess a rotational kinetic energy, simply from the classical equations that describe this property.
Of course, rotational bands are more complicated objects than your standard definition in classical mechanics, however, in much the same way as classical physics, I expect there to be corrections to the kinetic energy formula for much the same reason.
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I haven't provided you a direct example, simply because I haven't found the right kind of material yet. But by the Poincare space translations, there is no need for a system with a radius to possess such a thing as an ''intrinsic spin.'' This seems to be something that is being completely ignored, intrinsic spin was a property given to the electron because attempts to measure a radius have failed.
A poster in the link I gave you however, could give an example, albeit, it was verbal.
Let me find it, we'll go through it.
So he says
''If you're talking about a single particle, the rest mass is defined to be the total energy when the particle is at rest  there is no way to separately discuss contributions to this energy. Furthermore, "spin" does not represent a degree of freedom  there is no motion associated with it, and hence no kinetic energy.
Some compound particles on the other hand have genuine rotational degrees of freedom. A deformed (nonspherical) nucleus can rotate, and may therefore possess rotational bands: excited states with increasing angular momentum, and associated rotational kinetic energy.''
Reference https://www.physicsforums.com/threads/doesspinhaverotationalkineticenergy.540443/0 
Whereas I think the issue is problematic for pointlike systems. Our models can't seem to handle them as they natural create divergence problems.
One solution was to suggest field theory provided an answer by electron shielding of the particle, but study of the electron shape casts some doubt on this.
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It may take some time, but I'll write something up.
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Yes. Ok.
Maybe we should create a thread on this topic, gather as much evidence as we can for this argument. It's a good topic, I just wish it had started on better terms.
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If you mean there is a difference between something being pointlike and being a point in reality, fair enough, but there should be some things made clear about objects that act like they are point like interactions. Just because something tends to act like a pointlike object, does not tend to mean in physics it is. Classical physics already predicted early on that particle interactions would be pointlike in nature. I forget the mathematical details now, but this is true.
String theory of course, is about extended objects in space but are rescaled to interact like pointlike objects. ... Ok I just took a look at your link, what is it you mean Mordred about this point? The main question was actually about a nucleus and whether it has a rotational kinetic energy. I explained it can and will have if the nucleus is not perfectly spherical.
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5 minutes ago, Mordred said:
I don't see any trap he asked a valid question. Particles are not spinning balls the angular momentum term
That's a very big assumption you are making here, you are generalizing one rule for pointlike systems to objects in space which are clearly not pointlike.
Do you know why points cannot spin? It's because they have to rotate 720 degrees just to get back to their original orientation. Clearly, when you have a system which is not pointlike, there is no need to assume ''instinsic spin'' in fact, spin is a nonproblem for those kinds of objects. Atoms really do spin. You can't generalize a rule for pointlike fermions to all classes of particles and extended objects in spacetime.
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12 minutes ago, Mordred said:
Prove both myself and Swansont wrong. It should be a trivial matter if your correct
For me it always was a nontrivial matter with electrons But then Swansont knew that anyway because he has enough guile to mention it as a type of academic trap.
3 minutes ago, Strange said:I think swansont's position as a moderators is irrelevant. He is arguing from his position as a working physicist.
His position as a moderator means something to me. Second, if he is arguing as a ''working physicist,'' good for him. This kind of appeal of authority still doesn't make him right.
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Sorry, I didn't mean anything against you Mordred. You weren't exactly part of this discussion till now.
I don't change my opinions on Swansont. Sorry if it causes offence, I've felt pretty offended by the constant hounding of a moderator.
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What's the lower bound on the photon mass again, its some ridiculous ten to the minus power of something. I do not recall now.
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Previous experts?
Name them. No one here is an expert in my opinion. And I think you will find the evidence I provided is overwhelmingly in my favour, I find your behaviour, strange concerning this.
Your question was ''show me how the electron had a spin.'' I explained this was a red herring. You then went on to talk about protons, and other objects which are not pointlike.
Intrinsic spin was suggested to be required because a point cannot rotate classically. The electron is the only pointlike particle in existence, as far as we can tell. Atoms do rotate classically, and the nucleus rotates classically  there is no need for intrinsic processes, that's just woo woo.
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Still trying to decode the equation suggested by Arun and Sivaram. It turns out there is some history of the combining of the heat equation with Ricci flow.
[math]\frac{\partial T}{\partial t} = \nabla^2 T + R T[/math]Where [math]R[/math] is the Ricci scalar. So as we can see the curvature acts like the Laplacian.
http://www.sciencedirect.com/science/article/pii/S0001870811002763
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Just found this, seems strongly related and interesting https://phys.org/news/201408space.html
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The Ricci flow is
[math]\frac{\partial p}{\partial t} = \Delta p[/math]
which is analogous to the heat equation
[math]\frac{\partial u}{\partial t} = \Delta u[/math]
The reason why this approach may be fruitful becomes clear from a passage in wiki
''The reader may object that the heat equation is of course a linear partial differential equation—where is the promised nonlinearity in the p.d.e. defining the Ricci flow?
The answer is that nonlinearity enters because the LaplaceBeltrami operator depends upon the same function p which we used to define the metric. But notice that the flat Euclidean plane is given by taking . So if is small in magnitude, we can consider it to define small deviations from the geometry of a flat plane, and if we retain only first order terms in computing the exponential, the Ricci flow on our twodimensional almost flat Riemannian manifold becomes the usual two dimensional heat equation.''
Note then, it has the possibility to describe deviations in the flat geometry of Euclidean flat space.
It seems then their notation of [math]R[/math] may just be another notation to denote a ''Ricci Flow.''
A more interesting form of the Ricci flow does exist using the Ricci curvature
[math]\frac{d}{dt}g_{ij} = 2R_{ij}[/math]http://mathworld.wolfram.com/RicciFlow.html
The actual definition they have chosen is confusing because technically speaking the diffusion equation should have a factor of [math]\rho c[/math] attached to the LHS, which would allow you to construct the thermal diffusion [math]\alpha[/math]
[math]\rho c_p \frac{\partial T}{\partial t} = \kappa \nabla^2 T[/math]
Such as
[math] \frac{\partial T}{\partial t} = \alpha \nabla^2 T[/math]
[math]\alpha = \frac{\kappa}{\rho c_p}[/math]
This last equation is equivalent to the volumetric heat [math]\dot{Q}_V[/math].
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Summary of Investigations into Curves and Accelerations
In our case, we have already noticed before that these ''curves'' are equivalent to accelerations at infinitessimal regions. We linked those curvature dynamics to the temperature in the following way:[math]K_BT = \frac{1}{2}(\frac{ds^{\mu}}{d\tau} \cdot \frac{ds^{\mu}}{d\tau}) \equiv\ \frac{1}{2}<\dot{\psi}\dot{\psi}>[/math]
For the special case of [math]m = 1[/math]. We'll also set the Boltzmann constant to natural units for simplicity in the future.
It was noted, that the term [math]\frac{ds^{\mu}}{d\tau} \cdot \frac{ds^{\mu}}{d\tau}[/math] is nothing but the square of the metric curve. This too, was a squared metric definition [math]<\dot{\psi}\dot{\psi}>[/math].
The latter expression was encountered in our investigation of possible curvature in the Hilbert space:
[math]\sqrt{<\dot{\psi}\dot{\psi}>} = \int \int\ W(q,p)^2 \sqrt{<\psi\Gamma^2\psi>}\ dqdp \geq \frac{1}{ \pi \hbar}\sqrt{<\psiH^2\psi>}[/math]
Where we make use of the Wigner function. What's interesting is that it is often an unfounded assumption by many that the Hilbert space needs to be flat, or that there is any credible argument against a single system exerting their own curvatures on spacetime (since it is not illegal that particles can couple to their own gravitational fields, see the NewtonSchrodinger equation as an example), or that even infinitessimal regions need to be flat. A good example are the minimum distance candidates, like the Bure Metric, or the FubiniStudy metric.
The geodesic length was
[math]\psi_0  \psi_1 = \sqrt{2  2\cos \theta} = 2 sin\frac{\alpha}{2}[/math]
In which you can calculate the angle
[math]\cos \alpha = \frac{<\psi_0\psi_1> + <\psi_1\psi_0>}{2}[/math]
In which an inequality holds
[math]\cos \alpha \leq <\psi_0\psi_1>[/math]
and so that the length of the curve on some unit sphere was
[math]\arccos <\psi_0\psi_1>[/math]
and once again
[math]\frac{ds}{dt} \equiv \sqrt{<\dot{\psi}\dot{\psi}>}[/math]
We also constructed the MandelstamTamm inequalities, in a strong inequality between the functions:
[math]<\psi(0)\psi(t)>^2 \geq \cos^2\ \int \int (W(q,p)<\Gamma^2>  <\psi\Gamma^2\psi> )\Delta t\ dqdp \geq \cos^2(\frac{[<H>  <\psiH\psi> ]\Delta t}{\pi \hbar}) = \cos^2(\frac{\Delta H \Delta t}{\hbar})[/math]
for [math]0 < t < \frac{\pi \hbar}{2 \Delta H}[/math]. And is similar to a collapse time equation for the survival probabilities of the geometry of the system. Note also, we ended up constructing a theory of the acceleration which looked a lot like a gravitational version of the Schrodinger equation and was akin to talking to covariant derivative on some curve on a metric which took the form
[math]\nabla_n\dot{\psi}>\ = \frac{c^4}{8 \pi G} \int \int\ W(q,p)^2\ (\frac{d}{dx^n}\Gamma^{ij} + \Gamma^{i}_{n\rho} \Gamma^{\rho j} + \Gamma^{j}_{n \rho}\Gamma^{\rho}_{i})\psi>\ dqdp \geq \int\ \frac{1}{\hbar}(\frac{d}{dx^n}T^{ij} + \Gamma^{i}_{n\rho} T^{\rho j} + \Gamma^{j}_{n \rho}T^{\rho}_{i})dV\psi>[/math]
Do Particles Experience Curvature at Infinitesimal Regions?
Yes, I believe they can experience small curvatures  in fact, I want to bring our attention to Sakharov and his metric elasticity [math]\kappa = 8 \pi G[/math] and is probably related to the idea of the string tension [math]\frac{8 \pi G}{c^2}[/math] in which we have the elasticity related the gravitational permeability [math]\mu_0[/math] weighted by a factor of the speed of light squared [math]\frac{\mu_0}{c^2}[/math]  it implies that all interactions causing gravity by their contributions to the energymomentum tensor curve space with the same elasticity coefficient, which K. Arun has suggested may imply a microscopic origin for [math]G[/math]. Certainly, [math]P^{4}[/math] propagators can be entirely described by their space time curvatures (see references), and Nobel Prize Winner A. Salam has suggested his own version of ''strong gravity'' which involves a cosmological and particle scale value for [math]G[/math].
What threw me off in my initial investigations was a continued assumption I was reading on the internet suggesting infinitesimally small spaces are only flat. This seems though to be an assumption at best.
It is even suggested by some authors that even a fluctuation should exert a curvature in the vacuum! So long as the stress energy tensor is not zero, then all volumentric forms of energy exert deformations on the surrounding gemetry.
The energy associated to the heat [math]Q[/math] is often represented by the enthalpy
[math]\Delta Q = \Delta H = H_0  H[/math]
And the heat capacity is featured in the following equation in which measures how much energy is required to raise the temperature of a system
[math]\Delta H = c_p m \Delta T = c_p m(T_0  T)[/math]
and becomes the volumetric measure of the change of enthalpy if
[math]\Delta \mathbf{H} = c_p \rho \Delta T = c_p \rho(T_0  T)[/math]
Which is a form more encountered on the internet. The rate of flow of heat (as from Fourier's law) per unit area through some surface is proportional to the negative teperature gradient[math]\frac{\Delta Q}{\Delta t} = \kappa S \frac{\Delta T}{\mathbf{x}} = \kappa S \nabla T[/math]
In which [math]\mathbf{x}[/math] is a measure of thickness of the medium in which [math]\frac{\Delta T}{\mathbf{x}}[/math] is the temperature gradient [math]\nabla T[/math] and is always negative since heat flows one way (flows from the higher to lower temperatures always). [math]S[/math] is the shape operator.
Let's quickly compare these equations to one suggested by Arun et el. The metric elasticity can be understood in terms of the conductivity which is further related to the temperature in the following way:
[math]\Delta T = \kappa(r^2_0  r^2)[/math]
This is suggested as a direct solution to the heat gradient equation
[math]\frac{\partial R}{\partial t} = \kappa \nabla^2 R[/math]
They suggested that curvature flows, in the sense of a Ricci flow and [math]\kappa[/math] will play the role of the conductivity. I am still attempting to decode these equations as they did not define their variables very well  my initial opinion is that their form of equation is very similar to the separation of variables solution for the heat equation. If the second equation is the standard gradient equation for heat flow then we can compare it with the differential form of the heat equation,
[math]\frac{\partial T(x,t)}{\partial t} = \kappa \nabla^2 T(x,t)[/math]
This would suggest Arun and Sivaram have used a notation [math]R[/math] for the temperature which is... pretty irregular. Moreover, when they come to their proposed gravitational analogue of the equation in terms of the metric elasticity, they denote a small [math]r[/math] and so is confusing whether they are supposed to denote the same variable. You can get a similar equation through a process of the separation of variables, but is still unclear to me and since they have not properly denoted their variables, it will remain unclear until the lightbulb above my head sparks up.
Either way, this is a very good place to start an investigation on temperature and accelerations.
Ref.
https://arxiv.org/ftp/arxiv/papers/1205/1205.4624.pdfSalam, Abdus; Sivaram, C. (1 January 1993). "Strong Gravity Approach to QCD and Confinement".
https://www.unimuenster.de/Physik.TP/archive/fileadmin/lehre/NumMethoden/WS0910/ScriptPDE/Heat.pdf
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1 hour ago, Strange said:
Maybe. In fact, almost certainly. But we don’t yet have any theory that explains why collapse will stop, or what will happen instead.
This isn't exactly true there are a number of models which present theories which stop full collapse to singularities. They have been the focus of investigation for a long time now.
One such model is the Planck star, in which quantum gravitational corrections act like a negative pressure capable of even being the final stage of a collapse.
On 01/12/2017 at 8:16 PM, beecee said:Yeah good point.In that case it may actually act to increase angular momentum. Complicated? That is certainly an understatement!
Yet getting into this complicated scenario, could/should the angular momentum of the BH, act to prevent total compulsory collapse to the quantum/Planck level?
Possible.
One such treatment states that the angular momentum actually varies in size. If the angular momentum increases as size decreases there are centrifugal forces to take into consideration.There may need to be additional factors, but the centrifugal force (the apparent force you feel in a spinning frame) has been suggested by Michio Kaku as a proposed mechanism for keeping wormholes open.
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Kinetic energy of a nucleus
in Speculations
Posted
The wave particle duality as seen in the double slit experiment shows that the particle is not always a wave, so this idea that waves is all there is means nothing to me, sorry.
It's been suggested I am not posting mainstream science and I have contacted through the appropriate channels. Strange how I am being accused of being outside mainstream when I am posting quotes from other places which support this idea that rotation is a real property so long as there are internal degree's of freedom  by the way, I already said this had gone off topic when we started discussing ''my opinions'' on particles, yet I am shafted in the open even though I was somewhat baited into those discussions by Swansont. My original reply here stays, a nucleus can rotate and will have a rotational kinetic energy, anything that classical rotates, uses energy.