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Mordred

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Everything posted by Mordred

  1. here you can start by learning the real science behind the equations I posted. Site Articles (Articles written by PF and Site members) http://cosmology101.wikidot.com/redshift-and-expansion http://cosmology101.wikidot.com/universe-geometry Misconceptions (Useful articles to answer various Cosmology Misconceptions) http://www.phinds.com/balloonanalogy/ : A thorough write up on the balloon analogy used to describe expansion http://tangentspace.info/docs/horizon.pdf :Inflation and the Cosmological Horizon by Brian Powell http://arxiv.org/abs/1304.4446 :"What we have leaned from Observational Cosmology." -A handy write up on observational cosmology in accordance with the LambdaCDM model. http://arxiv.org/abs/astro-ph/0310808 :"Expanding Confusion: common misconceptions of cosmological horizons and the superluminal expansion of the Universe" Lineweaver and Davies http://www.mso.anu.edu.au/~charley/papers/LineweaverDavisSciAm.pdf:"Misconceptions about the Big bang" also Lineweaver and Davies http://arxiv.org/abs/1002.3966 "why the prejudice against a constant" http://arxiv.org/abs/gr-qc/0508052 "In an expanding universe, what doesn't expand? Richard H. Price, Joseph D. Romano http://arxiv.org/abs/1301.0219 What's in a Name: History and Meanings of the Term "Big Bang" Helge Kragh http://arxiv.org/pdf/hep-ph/0004188v1.pdf :"ASTROPHYSICS AND COSMOLOGY"- A compilation of cosmology by Juan Garcıa-Bellido http://arxiv.org/abs/astro-ph/0409426 An overview of Cosmology Julien Lesgourgues http://arxiv.org/pdf/hep-th/0503203.pdf "Particle Physics and Inflationary Cosmology" by Andrei Linde http://www.wiese.itp.unibe.ch/lectures/universe.pdf:"Particle Physics of the Early universe" by Uwe-Jens Wiese Thermodynamics, Big bang Nucleosynthesis there is two free open source textbooks there enjoy, they also detail the CMB in the later chapters
  2. This is pointless either show some mathematical rigor or I'm recommending this thread gets locked
  3. Einstein knows the importance of dimensional analysis in his equations
  4. The metrics I posted is 100% compatible with GR nice try
  5. start with defining a homogeneous and isotropic fluid. In the FLRW metric This fluid distribution is defined by [latex]d{s^2}=-{c^2}d{t^2}+a{t^2}[d{r^2}+{S,k}{r^2}d\Omega^2][/latex] [latex]S\kappa,r= \begin{cases} R sin(r/R &(k=+1)\\ r &(k=0)\\ R sin(r/R) &(k=-1) \end {cases}[/latex] a is the scale factor which correlates expansion [latex]Proper distance =\frac{\stackrel{.}{a}(t)}{a}[/latex] [latex]H(t)=\frac{\stackrel{.}{a}(t)}{a(t)}[/latex] acceleration equation is [latex]\frac{\ddot{a}}{a}=-\frac{4\pi G\rho}{3c^2}(\rho c^2+3p)[/latex] which leads to [latex]H^2=\frac{\dot{a}}{a}=\frac{8\pi G\rho}{3c^2}-\frac{kc^2p}{R_c^2a^2}[/latex] You can derive the cosmological redshift, temperature pressure etc from these equations
  6. Whats the point if you can't provide the correct mathematical details? You have no idea how many people we get with grandiose unsupported claims.
  7. Maybe I rather successfully make a living of physics, which I do. Your formula I already pointed out in your other thread is mathematically incorrect as it doesn't pass dimensional analysis. You have yet to address that issue
  8. I explore when I see mathematical accuracy not random unsupported claims and misconceptions.
  9. 100% inaccurate. If you reverse expansion to 10^-43 seconds our Observable portion of the universe is roughly the size of an atom. However that is only our observable portion. Not the entire universe, which can be finite or infinite. We simply don't know. All of which is simply described as a hot dense state who's average density decreases as a result of expansion.
  10. Start with the cosmological principle Strange is correct there is no edge. Start studying the actual metrics instead of making claims that make no sense. I can honestly state that in that I have a degree in Cosmology.
  11. yes this is accurate guage bosons are "off shell" and not identical to the full boson particle. A common name is vector guage boson.
  12. try temperature and the thermodynamic ideal gas laws. The measuring stick being the scale factor
  13. OK here is some 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 nitice 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 thee 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 thee 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".. You can see from this that as the field strength changes via the meta stability the mass values will also be influenced.
  14. No the cosmic neutrino background is also predicted by the BB model
  15. two very key questions well done +1 you have detailed part of the heart of the subject.
  16. just following the same logic you see in every paper under block. Take it as you will. Personally growing block or evolving block from my studies of block are more compatible with GR. Its not really a word game to stick with what the model or theory describes even on the philisophical grounds. Choosing a personal viewpoint and describing it with non standard to the model terminology just adds confusion. One of the biggest difficulties with strictly block is determinism. Mathematically this has specific connotations that cannot be ignored. Yes there is mathematical treatments of relativity to maintain determinism but these can get rather convoluted into fibre bundles which AJB mentioned before. lol Think about that for a bit. Then like I said literally google "relativistic presentism pdf". I quarantee you'll hit papers that state presentism as being incompatible with relativity.
  17. by the way careful on Hubbles constant. Its only constant at a given time. It increases greatly in the past. At the time of the CMB its roughly 1000 times greater than today. no problem wife will be at work then lol
  18. Well again we get into the details of false vacuum/true vacuum metastability which this all hinges upon. There is indications on both sides of the fence. Part of the problem is generating the needed energy ranges to fully test the Higg's metastibility and technicolor. If it helps tomorrow I should have time to post some metrics to better understand the Higg's itself. There is a particular good low math example in Ryder Lewis "Introductory to Cosmology" In cosmology terms were not sure if we are in a false vacuum or true vacuum state. There is potential of another symmetry break but like you I find this unlikely as our blackbody temperature is only 2.7 k. However thats a personal opinion not a scientific one.
  19. Yes but sterile neutrinos can have higher mass. Also the Higg's metastability can cause different mass values. The quantity of DM and neutrino predictions is also problematic there are solutions to that but again becomes model specific depending on the mass of the sterile neutrino. No apology needed by the way, it takes specific research into the topic to catch all the variations and to seperate the pop media poor misleading coverage. Most people don't even realize just how many variations there truly is. Even after 5 years study on this particular study I still find variants I've never encountered before. I don't know if you can afford textbooks but one of the best books covering the VeV and what it means is Mukhanov's Physical foundations of Cosmology. He goes into excellent on symmetry breaking. https://www.amazon.com/Physical-Foundations-Cosmology-Viatcheslav-Mukhanov/dp/0521563984 PS thanks for using my callsign lol I prefer that. +1 for catching some key details involved.
  20. To be honest your post is kind of random. Considering the subject matter breaks down to time-reversible symmetry with entropy as the arrow of time. There are quite frankly time reversible processes but As far as I know entropy isn't fully time reversible. At least not on a global universe scale. The low entropy beginning is quite simple to understand. All particles at the stages are in a state of thermal equilibrium. This state can be described simply via its temperature which correlates to photons. Via the Bose-Einstein statistics the entropy of photons (degrees of freedom) including its anti particle is S=2. As more particles decouple the entropy increases. You can find the sequence here. http://arxiv.org/pdf/hep-th/0503203.pdf "Particle Physics and Inflationary Cosmology" by Andrei Linde http://www.wiese.itp.unibe.ch/lectures/universe.pdf:"Particle Physics of the Early universe" by Uwe-Jens Wiese Thermodynamics, Big bang Nucleosynthesis The second article in chapter 3 and 4 is better coverage. One of the details of specifically block is deterministic which amounts to time reversible processes. Though that alone can be a lengthy discussion best left under philosophy. The thing is you mentioned several different models under one post so its difficult to determine the direction of your question. Here is some of the counter arguments for the Block deterministic view. Overall: a lack of predictability in the real universe In summary, the future is not determined till it happens (a) time-dependent equations of state, which can be information driven, (b) quantum uncertainty, which can be amplified to macro scales, and also in practice by © statistics / experimental errors / classical fluctuations, amplified by (d) chaotic dynamics /occurrence of catastrophes. Essentially all realistic models of the universe except for very large scale cosmology are non-deterministic. Sufficient reasons for this are: (i) coarse-graining by its very nature introduces a statistical element; and (ii) quantum processes occur on the small scale, and can be amplified to macro scales, so there is no deterministic microscopic model from which fully predictive classical macroscopic models can always be derived. You can review these here. Which is the source https://www.google.ca/url?sa=t&source=web&rct=j&url=https://arxiv.org/pdf/gr-qc/0605049&ved=0ahUKEwi3hIuamq_QAhUN5WMKHU-HBnQQFggaMAA&usg=AFQjCNHbifo4qFdaYMpt31beTJ-3cIxzSA Personally I don't find the arrow of time well represented by entropy. The term entropy is often too confused. However thats just me I find it an unimportant debate and just stick to time is a measure of rate of change. Without trying to glorify it beyond that. Which we often see on this forum. Wiki covers this a bit but doesn't explain it well. https://en.m.wikipedia.org/wiki/Entropy_(arrow_of_time) The main detail is whether the universe is time symmetric or time assymmetric.
  21. Well the best way to learn the required details is to study how symmetry breaking occurs due to temperature. There is a key term to understand "thermal equilibrium " it is specifically when particles become indistinguishable including via momentum. For example before electroweak symmetry breaking and the Higgs field decoupling the particles you mentioned are fully relativistic and indistinguishable from photons. So the better question is when do particles slow down due to coupling and gain mass.
  22. Will you quit with this "Resident expert" bit. I do have a callsign please use it. I can quarantee research hadn't stopped on sterile neutrinos candidate for dark matter despite that link you posted. I also specified its one possibility. In point of detail here is a 256 page coverage written in Feb 2016. There is some key details you need on the link you provided. I will detail this at the end. http://www.google.ca/url?sa=t&source=web&cd=2&ved=0ahUKEwj62oSPgK_QAhXIjlQKHertC68QFggdMAE&url=https%3A%2F%2Farxiv.org%2Fpdf%2F1602.04816&usg=AFQjCNFWEv0XhB7y8PFxMsgnsWZdQb4JzQ Make your own opinion there is still validity in the possibility. The possibility has not been ruled out yet. By the way the sterile neutrino possibility doesn't require supersymmetry. Although SO (10) MSSM is the strongest support for the sterile neutrino theory. The model is also possible under SO (10) MSM. Though its incredibly difficult to find the minimal symmetric standard model variations. reference 181, 182 of that link. Don't let pop media articles fool you. Study the model itself and make a self informed opinion. We can exchange counter papers all day long and not change each others opinion. For example there is several possible types of sterile Neutrinos. eV scale, KeV scale and MeV scale. The paper I posted discusses all three but supports the KeV scale. The low mass reference in that link you provided is the eV scale specifically. You don't see these details from the pop media literature. Here under the full paper is the specification "light sterile neutrino" which is in the eV mixing range. It doesn't test the keV nor MeV mixing range. Here is the details I included the paper to your link " Resonant oscillations due to matter eects would produce distinctive signatures of sterile neutrinos in the large set of high energy atmospheric neutrino data recorded by the IceCube Neutrino Observatory. The IceCube collaboration has performed searches for sterile neutrinos with m2 between 0:1 and 10 eV^2. " Doesn't copy paste well from the arxiv paper but here is the arxiv covering your link. The test range is detailed in the conclusions. Like I said don't let pop media coverage fool you. That test only shows a less likely hood of sterile neutrinos in 0.1 to 10 eV range. https://arxiv.org/abs/1605.01990 Side note that range is too short lived to be a good DM candidate. The lifetime is too short in this case. Also the eV range would make it relativistic which would be hot dark matter not cold dark matter. The link I provided mentions that detail however as stated it supports the keV range as a DM candidate. Not all papers do, its one of many possible. (just a side note you often see seesaw 1 and seesaw 2 but under SO (10) MSSM I've read papers discussing as high as seesaw VI.) though usually in dissertations.) though that requires finding Higglets
  23. close enough
  24. The CMB surface of last scattering is at a time when the universe is 380,000 years old. Prior to that period we hit an opaque dense region where the mean free path of photons become too short. Too much clutter as atoms haven't formed. This is referred to as the dark ages. Due to this we never see the BB itself. Though we will possibly be able to measure further with neutrinos ( cosmic neutrino background) The density at roughly this time had sufficient hydrogen to form stars in the later stages of last scattering. Provided the temperature has dropped sufficiently to support hydrogen atoms.
  25. Wouldn't a more practical question be "What slows down a particle"? Ie mass=resistance to inertia. What interaction gives the gluons mass? As far as your model idea goes Not enough detail to judge atm
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