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Mordred

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Everything posted by Mordred

  1. Unfortunately I read far too many misconceptions of string theory being applied on the other forum that I cannot see any accuracy of string theory being applied. Though you at least had a decent understanding of the involved symmetry groups. ie the [math]E_8[/math] group as one example.
  2. Building models of advanced physics without understanding basic physics would be like building a house without a foundation.
  3. Thats where the mathematical precision comes into play. Once you define a state under math it becomes trivial to apply it to different theories. One can readily apply every equation I posted in this thread to QFT, Loop quantum gravity and even string theory etc or simply describe the above under a classical approximation. No it wouldn't require a Ph.D but one can easily think it would. There is nothing preventing someone learning physics and even self teaching with the correct diligence. (here is a little secret, the most complex models derive from the simplest). Would it surprise you that every equation I posted can be broken down to its basic kinematic components taught in grade school? Ie scalar and vector quantities
  4. Any representation including images can be described via math. The question becomes how to properly do so. Start with breaking your images to a coordinate basis. Then attempt to break said image into vectors. Finally look for symmetry and assymetry relations to organize said vectors. I wish I could recall a particular theory that literally breaks any picture one can take and describe it under math. Its not strictly physics but the mathematics can be related to physics. The problem I found reading your post on the other thread was the lack of proper descriptives via proper terminology. You tend to try to apply a scattering of random theories, some of which have little to do with one another. Its actually a struggle to figure out where to start to help you advance your ideas to proper physics descriptives. Unfortunately as Vmedvil started this post as the OP the priority I applied is more to his posts than yours. This is to prevent thread hijacking. I suggest starting a seperate thread under Speculation so I can properly focus on your particular ideas. One other rule to follow, never reply to a thread with personal models. Always answer via mainstream physics.
  5. I always have to spend time on your posts lol. They are precise enough to warrent the proper time to reply
  6. One thing I truly appreciate about your threads Dubbelsix is you spent literally dozens of posts simply to accurately describe the length of a vector. One of the most vital aspects of group theory. You then applied that under a precise coordinate basis. A vast majority of your posts literally applied to a complete tensor closure. Unfortunately not many understood the Dirac notation. You then specified at every post including your own site that you are toy modelling. Not once have I ever seen you state this is the way it is. Yet you always maintained proper mathematical rigor in every examination you performed. The bonus is you much like me can pick up any professional peer review topic and understand it correctly via understanding the mathematics and not the written descriptives or images. That is the true advantage learning vector calculus and differential geometry provides... Like I said every equation has a precise mathematical proof that must be properly understood before trying to manipulate it. After 25 years of intensive study of physics. One becomes amazed on just how interconnected various theories are
  7. OK lets do some math to show some details first lets describe how the Bose Einstein works in a heuristic manner ie a more familiar examiniation [latex]DU=pdV[/latex]. First take the first law of thermodynamics. [latex]dU=dW=dQ[/latex] U is internal energy W =work. As we dont need heat transfer Q we write this as [latex]DW=Fdr=pdV[/latex] Which leads to [latex]dU=-pdV.[/latex]. Which is the first law of thermodynamics for an ideal gas. [latex]U=\rho V[/latex] [latex]\dot{U}=\dot{\rho}V+{\rho}\dot{V}=-p\dot{V}[/latex] [latex]V\propto r^3[/latex] [latex]\frac{\dot{V}}{V}=3\frac{\dot{r}}{r}[/latex] Which leads to [latex]\dot{\rho}=-3(\rho+p)\frac{\dot{r}}{r}[/latex] We will use the last formula for both radiation and matter. Assuming density of matter [latex]\rho=\frac{M}{\frac{4}{3}\pi r^3}[/latex] [latex]\rho=\frac{dp}{dr}\dot{r}=-3\rho \frac{\dot{r}}{r}[/latex] Using the above equation the pressure due to matter gives an Eos of Pressure=0. Which makes sense as matter doesn't exert a lot of kinetic energy/momentum. For radiation we will need some further formulas. Visualize a wavelength as a vibration on a string. [latex]L=\frac{N\lambda}{2}[/latex] As we're dealing with relativistic particles [latex]c=f\lambda=f\frac{2L}{N}[/latex] substitute [latex]f=\frac{n}{2L}c[/latex] into Plancks formula [latex]U=\hbar w=hf[/latex] [latex]U=\frac{Nhc}{2}\frac{1}{L}\propto V^{-\frac{1}{3}}[/latex] Using [latex]dU=-pdV[/latex] using [latex]p=-\frac{dU}{dV}=\frac{1}{3}\frac{U}{V}[/latex] As well as [latex]\rho=\frac{U}{V}[/latex] leads to [latex]p=1/3\rho[/latex] for ultra relativistic radiation. Those are examples of how the first law of thermodynamics fit within the equations of state. There is more intensive formulas involved. In particular the Bose-Einstein statistics and Fermi-Dirac statistics. You can fit that into the previous post where I detailed those statistics. This shoulld better help you understand that portion. Now lets supply some details on GR in particular the Newton limit Central potential and Newton limit In the presence of matter or when matter is not too distant physical distances between two points change. For example an approximately static distribution of matter in region D. Can be replaced by the equivalent mass [latex]M=\int_Dd^3x\rho(\overrightarrow{x})[/latex] concentrated at a point [latex]\overrightarrow{x}_0=M^{-1}\int_Dd^3x\overrightarrow{x}\rho(\overrightarrow{x})[/latex] Which we can choose to be at the origin [latex]\overrightarrow{x}=\overrightarrow{0}[/latex] Sources outside region D the following Newton potential at [latex]\overrightarrow{x}[/latex] [latex]\phi_N(\overrightarrow{x})=-G_N\frac{M}{r}[/latex] Where [latex] G_n=6.673*10^{-11}m^3/KG s^2[/latex] and [latex]r\equiv||\overrightarrow{x}||[/latex] According to Einsteins theory the physical distance of objects in the gravitational field of this mass distribution is described by the line element. [latex]ds^2=c^2(1+\frac{2\phi_N}{c^2})-\frac{dr^2}{1+2\phi_N/c^2}-r^2d\Omega^2[/latex] Where [latex]d\Omega^2=d\theta^2+sin^2(\theta)d\varphi^2[/latex] denotes the volume element of a 2d sphere [latex]\theta\in(0,\pi)[/latex] and [latex]\varphi\in(0,\pi)[/latex] are the two angles fully covering the sphere. The general relativistic form is. [latex]ds^2=g_{\mu\nu}(x)dx^\mu x^\nu[/latex] By comparing the last two equations we can find the static mass distribution in spherical coordinates. [latex](r,\theta\varphi)[/latex] [latex]G_{\mu\nu}=\begin{pmatrix}1+2\phi_N/c^2&0&0&0\\0&-(1+2\phi_N/c^2)^{-1}&0&0\\0&0&-r^2&0\\0&0&0&-r^2sin^2(\theta)\end{pmatrix}[/latex] Now that we have defined our static multi particle field. Our next step is to define the geodesic to include the principle of equivalence. Followed by General Covariance. Ok so now the Principle of Equivalence. You can google that term for more detail but in the same format as above [latex]m_i=m_g...m_i\frac{d^2\overrightarrow{x}}{dt^2}=m_g\overrightarrow{g}[/latex] [latex]\overrightarrow{g}-\bigtriangledown\phi_N[/latex] Denotes the gravitational field above. Now General Covariance. Which use the ds^2 line elements above and the Einstein tensor it follows that the line element above is invariant under general coordinate transformation(diffeomorphism) [latex]x\mu\rightarrow\tilde{x}^\mu(x)[/latex] Provided ds^2 is invariant [latex]ds^2=d\tilde{s}^2[/latex] an infinitesimal coordinate transformation [latex]d\tilde{x}^\mu=\frac{\partial\tilde{x}^\mu}{\partial x^\alpha}dx^\alpha[/latex] With the line element invariance [latex]\tilde{g}_{\mu\nu}(\tilde{x})=\frac{\partial\tilde{x}^\mu \partial\tilde{x}^\nu}{\partial x^\alpha\partial x^\beta} g_{\alpha\beta}x[/latex] The inverse of the metric tensor transforms as[latex]\tilde{g}^{\mu\nu}(\tilde{x})=\frac{\partial\tilde{x}^\mu \partial\tilde{x}^\nu}{\partial x^\alpha\partial x^\beta} g^{\alpha\beta}x[/latex] In GR one introduces the notion of covariant vectors [latex]A_\mu[/latex] and contravariant [latex]A^\mu[/latex] which is related as [latex]A_\mu=G_{\mu\nu} A^\nu[/latex] conversely the inverse is [latex]A^\mu=G^{\mu\nu} A_\nu[/latex] the metric tensor can be defined as [latex]g^{\mu\rho}g_{\rho\nu}=\delta^\mu_\mu[/latex] where [latex]\delta^\mu_nu[/latex]=diag(1,1,1,1) which denotes the Kronecker delta. Finally we can start to look at geodesics. Let us consider a free falling observer. O who erects a special coordinate system such that particles move along trajectories [latex]\xi^\mu=\xi^\mu (t)=(\xi^0,x^i)[/latex] Specified by a non accelerated motion. Described as [latex]\frac{d^2\xi^\mu}{ds^2}[/latex] Where the line element ds=cdt such that [latex]ds^2=c^2dt^2=\eta_{\mu\nu}d\xi^\mu d\xi^\nu[/latex] Now assume that the motion of O changes in such a way that it can be described by a coordinate transformation. [latex]d\xi^\mu=\frac{\partial\xi^\mu}{\partial x^\alpha}dx^\alpha, x^\mu=(ct,x^0)[/latex] This and the previous non accelerated equation imply that the observer O, will percieve an accelerated motion of particles governed by the Geodesic equation. [latex]\frac{d^2x^\mu}{ds^2}+\Gamma^\mu_{\alpha\beta}(x)\frac{dx^\alpha}{ds}\frac{dx^\beta}{ds}=0[/latex] Where the new line element is given by [latex]ds^2=g_{\mu\nu}(x)dx^\mu dx^\nu[/latex] and [latex] g_{\mu\nu}=\frac{\partial\xi^\alpha}{\partial\xi x^\mu}\frac{\partial\xi^\beta}{\partial x^\nu}\eta_{\alpha\beta}[/latex] and [latex]\Gamma^\mu_{\alpha\beta}=\frac{\partial x^\mu}{\partial\eta^\nu}\frac{\partial^2\xi^\nu}{\partial x^\alpha\partial x^\beta}[/latex] Denote the metric tensor and the affine Levi-Civita connection respectively. now as the topic of Higg's came up lets supply some details on this. Higg's field details that will make understanding the Higg's itself simpler. Keep in mind I am using Lewis Ryder "Introductory to General Relativity" for this. You may find more recent articles with slightly different metrics. (PS this will take me some time to type in and latex)First we need to notice that there is actually 4 field quanta in electro-weak theory. [latex]\gamma, W^-, W^+, and, Z^o.[/latex] notice the second and third is an antiparticle pair. Now the problem is we need a mechanism to give the neutrinos mass without giving photons mass. This is where the Higg's mechanism steps in. To start with Peter Higg's looked at superconductivity. The defining characteristic of conductivity is that at a temperature below a critical temperature [latex]T_c[/latex] some metals lose all electrical resistance. Resistance literally becomes zero, not merely very small. [latex](E=Rj) =j=\sigma E[/latex] where [latex]\sigma[/latex] is the conductivity. A metal in conductivity state then exhibits a persistant current even in no field:[latex]j=\not=0[/latex] when E=0. The key to understanding superconductivity is to describe the current as supercurrent [latex]j_s[/latex]. But unlike the equation above to realize this is proportional not to E but to the vector potential A. [latex]j_s=-k^2A[/latex] with a negative proportionality. This is the London equation. The relevant property we however are seeking is the Meissner effect, which is a phenomena that the magnetic flux is expelled from superconductors. Higg's then showed that suitably transformed into a relativistic theory, this is the equivalent to showing the photon has mass. (just not rest mass lol) The reasoning goes as follows. First the London equation explains the Meissner effect, for taking the curl of Amperes equation[latex]\nabla*BB=j[/latex] gives [latex]\nabla(\nabla^2B=\nabla*j[/latex] noting that [latex]\nabla*B=0[/latex] (no magnetic monopoles) gives [latex]\nabla^2B=k^2B[/latex] which is equal to [latex]\nabla^2A=k^2A[/latex] In one dimension the solution to this is [latex]B(x)=B(0)exp(-kx)[/latex] which describes the Meissner effect-the magnetic field is exponentially damped inside the superconductor, only penetrating to a depth of order 1/k. This however is still non relativistic. To make it relativistic [latex]\nabla^2[/latex] is replaced by the Klein_Gordon operator [latex]\Box[/latex] and A by the four vector [latex]A^\mu=(\phi,A)[/latex] giving [latex](\frac{1}{c^2}\frac{\partial^2}{\partial t^2}+\frac{\partial^2}{\partial x^2}+\frac{\partial^2}{\partial y^2}+\frac{\partial^2}{\partial x^2})A^\mu=k^2A^\mu[/latex] the vector potential is a field but we are currently interested in the photon, the quantum of the field. so we make the transition to quantum theory by the usual description. [latex]\frac{\partial}{\partial t}\mapsto-\frac{i}{\hbar}E, \frac{\partial}{\partial}{\partial x}\mapsto\frac{i}{\hbar p_x}....[/latex]etc giving the quantum of the field [latex]A^\mu[/latex], [latex]E^2-p^2c^2=k^2c^2\hbar^2[/latex] where E is the total, including rest energy of the field quantum an p isits momentum comparison to [latex]E^2-p^2c^2=m^2c^4[/latex] implies that the mass of the quantum in a superconductor is [latex]m_\gamma=\frac{k\hbar}{c}[/latex] the photon behaves as a massive particle in a superconductor. This is the import of the Meissner effect. Now we need to make a further connection to the Bardeen-Cooper_Schreiffer (BCS theory) of superconductivity which is a microscopic theory that accounts for superconductivity by positing a scalar field [latex]\phi[/latex] (spin zero for scalar fields). Which describes a Cooper pair of electrons, the pairing is in momentu space rather than coordinate space. You can correlate the many particle wave function of Cooper pairing with the above. I'm trying to save time here lol and this is already getting lengthy. The main difference between a superconductor and the Higg's field is that the Higg's field is all pervasive unlike (unlike BCS which is inside a superconductor) The Higg's field through treatment gives rise to the mass of the above neutrinos in the same manner but not to photons. In point of detail the Higg's field can be treated as 4 separate fields one for each of the above. latex]\gamma, W^-, W^+, and, Z^o.[/latex] Now the Higg's potential when [latex]t<t_c[/latex] has a maximum at [latex]\phi=0[/latex] and two minima at [latex]\phi=\pm A[/latex] when[latex] t>t_c][/latex] there is only a minimal at [latex]\phi=0[/latex] THIS is the Mexican hat potential. [latex]V \phi=\frac{m^2}{2}\phi^2+\frac{\lambda}{4}\phi^4[/latex] where [latex]\phi^4[/latex] is the quartic self interaction.. The extremal values of [latex]V\phi[/latex], given by [latex]\partial V/\partial \phi=0[/latex] becomes[latex]\phi=0,\pm\sqrt{\frac{-m^2}{\lambda}}=0,\pm a[/latex]when there is no field [latex]\phi=0[/latex], the energy is not a mimimal but at a maximal, further more the lowest energy is a state in which the field does not vanish and is also two fold degenerate. I hope that helps better understand the Higg's field and how it came about ie was derived in the first place. Section 10.10 Lewis Ryder "Introduction to General Relativity".. Scalar field Dynamics here we need to couple the scalar field to gravitation. [latex]\frac{1}{2}\dot{\phi}^2+\frac{1}{2}(\triangledown\phi^2)+V(\phi)[/latex] and the dynamics can be described by two equations. ::Friedmann equations [latex]H^2+\frac{k}{a^2}=\frac{8\pi}{3M^2_P}(\frac{1}{2}(\dot{\phi})^2+V(\phi)[/latex] and the Klein Gordon equation obeys the scalar fields [latex]\ddot{\phi}+3H\dot{\phi}+\acute{V}(\phi)=0[/latex] if the [latex]\phi_a[/latex] is large we have [latex](\triangledown \phi_a^2)<<V(\phi_2)[/latex] the speed of expansion [latex]H=\frac{\dot{a}}{a}[/latex] is dominated by the potential [latex]V(\phi_a)[/latex] in equation[latex]H^2+\frac{k}{a^2}=\frac{8\pi}{3M^2_P}(\frac{1}{2}(\dot{\phi})^2+V(\phi)[/latex] the advantage of Higg's inflation is that inflation is readily modelled using just the standard model of particles. We do not need k-Fields, inflatons, curvatons, Quintessence or any other quasi particle or field. Secondly we can model inflation as a symmetry phase transistion which is extremely important as we tie inflation with the electro-weak symmetry breaking itself. Higg's inflation. Higg's field. Is a complex scalar field [latex]SU(2)_w[/latex] doublet. [latex]\phi=(\begin{matrix}\phi_1 & \phi_2 \\ \phi_3& \phi_4 \end{matrix})[/latex] the vector bosons (guage bosons) interact with the four real components [latex]\phi_i[/latex] of the [latex]SU(2)_{w^-}[/latex] symmetric field [latex]\phi[/latex] false vacuum corresponds to [latex]\phi=0 or \phi_1=\phi_2=\phi_3=\phi_4=0[/latex] the true vacuum corresponds to [latex]\phi_1=\phi_2,,,\phi_3^2=\phi_4^2=constant>0[/latex] assign V on the Y axis, [latex]\phi_3[/latex] on the x axis, [latex]\phi_4[/latex] on a 45 degree between the x and Z axis. when you have conditions [latex]\phi_4=0,\phi_3>0[/latex] then the rotational symmetry is spontaneously broken. The Higg's boson becomes massive as well as the vector bosons W+,W-Z and photons the two neutral fields [latex]B^0 and W^0[/latex] form the linear combinations [latex]\gamma=B^0 cos\theta_w+W^0sin\theta_w[/latex] [latex]Z^0=-B^0sin\theta_w+W^0cos\theta_w[/latex] where Z becomes massive. whee as our ordinary photon [latex]\gamma[/latex] remains massless as the photon does not interact with the electro-weak Higg's field. It is electro-weak neutral. The electroweak symmetry is given by [latex]SU(2)_w\otimes U(1)_{b-L}[/latex] as time decreases the vacuum expectation value [latex]\theta_0[/latex] decreases. (expansion in reverse) the true minimal of the potential is [latex] \phi=0[/latex] this occurs above the critical temperature [latex]T_c=\frac{2\mu}{\sqrt{\lambda}}[/latex] at this point the field interactions take on in essence superconductivity properties. Now isn't that far more precise than images??? Every formula in physics has a mathematical proof, every definition has a mathematical precision. This is only a very miniscule portion of developing an effective GUT>>> We haven't even touched on [math]SO(10)\otimes SO(5)\otimes SO(3)\otimes SO(2)\otimes U(1)[/math] Do you actually believe your images compares to the mathematical precision involved in symmetry breaking via the SO(10)??? How does one make a single prediction with nothing more than images? How can you possibly determine all possible paths involved in a two particle interaction let alone a multi particle system?
  8. this will be better if I work up some FRW solutions to see the above but will have to do this tomorrow. It will help understand how the EoS applies to the fluid equations via the FRW metric.
  9. Yes correct you would have at some point needed it. man I hate reading equations in this format let me go thru this tomorrow its late atm and I'm starting to not think clearly
  10. function of the momentum ie momentum as a function
  11. Ok this gets a bit complex. Think of particles as field excitations. Under QFT the operators correspond to the field itself as being the operator. Now particle production always occur in pairs to maintain the conservation laws applicable to the Eightfold Wayen. Conservation of charge, lepton number, parity, flavor,color,parity etc. Ordinarily these pairs would annihilate however they get separated via expansion depending on their momentum and rate of expansion in essence. Now unfortunately we encounter an assymetry in this in that for some unknown reason the number density of matter vs antimatter don't stay balanced. Which is good as the universe wouldn't exist without this assymmetry. This is one of the unsolved problems called leptogenesis and baryogenesis. Afiak the best viable solution involves the Higg's field but this work is still under scutiny. Its actually where my current studies is focusing on The Higg's field involvement in the FRW metric though I have run into a few problems. Mainly lack of applicable observational data lol though that is coming in gradually via CERN etc. The main problem is the seesaw mechanism itself
  12. Forgot to add particles are always created in pairs matter/antimatter. Expansion separates those pairs allowing the decoupling from equilibrium.
  13. If you apply the above to each particle species to each corresponding equation of state derived using the above and using the Bose-Einstein/Fermi_Dirac statistics and can maintain a homogenous and isotropic state under rotation as the volume increases then yes. However keep in mind the article I posted on the upper boundary limits I posted earlier which applies the above. If you go through that arxiv link you will see that it also applies these statistics under rotation inclusive to the FRW fluid equations.
  14. Start with a box volume [math]V=L^3[/math] with periodic boundary conditions. Apply the Schrodinger equation to give the energy and momentum eugenstates. where the possible momentum values are [math]\vec{p}=\frac{h}{L}(n_1\hat{x}+n_2\hat{y}+n_3\hat{z})[/math] [math](n_i=0,\pm1,\pm2...)[/math] the state density in momentum space ie number of states [math]\Delta p_x,\Delta P_y\Delta p_z[/math] is thus [math]\frac{L^3}{h^3}=\frac{V}{h^3}[/math] and the state density in phase space is [math](\vec{x},\vec{p})[/math] is [math]\frac{1}{h^3}[/math] if the particle has g internal degrees of freedom (eg spin) the density of states is [math]\frac{g}{h^3}=\frac{g}{(2\pi)^2}[/math] [math](\hbar=\frac{h}{2\pi}=1)[/math] this is true even in the relativistic case. The particle energy if given by [math]E(\vec{p})=\sqrt{p^2+m^2}[/math] where [math]p=|\vec{p}|[/math] don't confuse this with pressure. There is two classifications of particles Bosons and fermions. In thermodynamic equilibrium the distribution function is given by the following equation [math]f(\vec{p}=\frac{1}{e^{(E-\mu)/T}\pm1}[/math] where the + is the bosons and - for the fermions. If f<1 f gives the probability that a state is occupied. (Paulis exclusion principle). The equilibrium distribution function has two distinct parameters T the temperature and the chemical potential [math]\mu[/math] The temperature is related to the energy density of the system ad the chemical potential is related to the number density (n) of particles in the system. The particle density in phase space is the density of states times their occupation number [math]\frac{g}{(2\pi)^3}f(\vec{p}[/math] we get the particle density in (ordinary space) by integrating over the momentum space to arrive at the following quantities. number density [math] n=\frac{g}{(2\pi)^3}[/math] energy density [math]\rho=\frac{g}{2\pi^3}\int E(\vec{p}f(\vec{p})d^3p[/math] pressure [math]p=\frac{g}{(2\pi)^3}\int\frac{|\vec{p}|^2}{3E}f(\vec{p}d^3p[/math] now particles can be in kinetic equilibrium, thermal equilibrium and chemical equilibrium. see the uwe jen weise article I linked earlier to cover how the above applies to nucleosynthesis
  15. Ok lets do this the correct way. Lets start with particles in a box in terms of thermal equilibrium. This will take me a bit to latex in so bear with me
  16. Every definition under physics is mathematically precise.
  17. Out of the box ideas are absolutely useless unless you can them up with the correct mathematics. This is physics not guess work and unsupported conjectures based on personal ideas. Drawings are not compliant to the mathematical rigor required as per the link on the other forum.
  18. No a spinning object by definition in anistropic and inhomogeneous you won't get a uniform temperature distribution. So how thermal equilibrium would work under the Godel type metrics gets rather complex. One of the most common problems with posters trying to model build toy universes is skipping numerous key lessons one would get via training at a university. One of the most common areas of study most don't understand is how thermodynamics relate to expansion rates and thermal decoupling.
  19. No that's not how thermal dynamic equilibrium works. Not in Cosmology applicaions. https://en.m.wikipedia.org/wiki/Decoupling_(cosmology) There is a very distinct relation between the particle species involved and when they decouple in relationship to rates of expansion.
  20. Well lets properly define this and avoid the confusion. I have a good reference for you to read http://www.wiese.itp.unibe.ch/lectures/universe.pdf :" Particle Physics of the Early universe" by Uwe-Jens Wiese Thermodynamics, Big bang Nucleosynthesis. See chapters 3 and 4 covering the Bose-Einstein and Fermi-Dirac statistics
  21. Why would it depend on the objects mass and not its density to thermodynamic relations via the equations of state and thermal equilibrium of particle species?
  22. Lol not exactly a scientific definition. How big ? how small? how do you define this boundary ? What is the point where curvature becomes measurable? ie where light paths convergence/divergence begins to be potentially measurable ? Lets use the example at 10^{43} seconds where the observable universe is contracted to roughly the radius of a grapefruit. Does curvature matter? this is a state that can be accurately described strictly by its temperature. All particles are in thermal equilibrium. Yet once electroweak symmetry breaking occurs you get rapid inflation.
  23. Where would you find this operator in the hydrodynamic equations pertianing to an adiabatic fluid expansion ? (adiabatic meaning no net inflow/outflow of heat). The FRW fluid equations is derived using an adiabatic and isentopic fluid. Ok let me dig up the peer review upper boundary to a rotating universe. I had posted this to one of Dubblesix threads when he first proposd his idea here. Here is the arxiv on the upper bound. https://arxiv.org/abs/0902.4575 Models of a rotating universe have been studied widely since G{\"o}del \cite{1}, who showed an example that is consistent with General Relativity (GR). By now, the possibility of a rotating universe has been discussed comprehensively in the framework of some types of Bianchi's models, such as Type V, VII and IX \cite{2,3}, and different approaches have been proposed to constrain the rotation. Recent discoveries of some non-Gaussian properties of the Cosmic Microwave Background Anisotropies (CMBA) \cite{nG1,nG2,nG3,nG4,nG5,nG6,nG7}, such as the suppression of the quadrupole and the alignment of some multipoles draw attention to some Bianchi models with rotation \cite{bi1,bi2}. However, cosmological data, such as those of the CMBA, strongly prefer a homogeneous and isotropic model. Therefore, it is of interest to discuss the rotation of the universe as a perturbation of the Robertson-Walker metric, to constrain the rotating speed by cosmological data and to discuss whether it could be the origin of the non-Gaussian properties of the CMBA mentioned above. Here, we derive the general form of the metric (up to 2nd-order perturbations) which is compatible with the rotation perturbation in a flat Λ-CDM universe. By comparing the 2nd-order Sachs-Wolfe effect \cite{4,5,6,7,8} due to rotation with the CMBA data, we constrain the angular speed of the rotation to be less than 10−9 rad yr−1 at the last scattering surface. This provides the first constraint on the shear-free rotation of a ΛCDM universe.
  24. Um please clarify that, when would it leave spacetime? Remember a Schwartzchild radius is derived from an observer in the same reference frame as the background metric (fundamental observer) a different observer will see a different EH. One has to watch out for artifacts of a metric this is where changing to tortoise coordinates etc come on handy
  25. Which in turn would affect lightpath null geodesics in terms of curvature. Lol another cross post. There is an upper bound to universe rotation required to maintain a homogenous and isotropic expansion
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