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Mordred

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Everything posted by Mordred

  1. Ah I like my avatar. Suits the evil son of King Arthur. (Mordred) but lost in thought. If that costs me potential rep points so be it lol
  2. Yes but part of the problem you were having was the radiated mass. In order to calculate the radiated mass you must calculate the total mass of the BINARY SYSTEM. Each wave emits a portion of that total mass. In other words every wave emits a %. So after each wave is emitted you must recalculate the total mass to calculate the emitted mass of the next wave. Which isn't as easy as it sounds as you need to account for kinetic as well as potential energy of the binary system. This is why you see an increase in amplitude of the waveform page 11 The change in frequency is due to chirp frequency including the ringdown phase http://www.physics.usu.edu/Wheeler/GenRel2013/Notes/GravitationalWaves.pdf I hope you understand that now.
  3. Still lol strain occurs every cycle of a frequency. Ringdown is a measure of frequency changes. That was why I was confused by your use of the polarity formula Which is handy to visualize a single wave. But frequency involves multiple waves. So does ringdown
  4. I still think you were using the wrong equation for the ringdown phase. But here you decide. http://www.google.ca/url?q=http://arxiv.org/pdf/1506.00560&sa=U&ved=0ahUKEwjt-JTCtuzLAhVH42MKHb36DhsQFggcMAM&usg=AFQjCNFB0NtD0cy_mhjGnaTAh2RDLNKdIg See equation 6 Which is the equation to model the ringdown waveform. Note the similarities to the chirp formulas page 10 and 11? http://www.physics.usu.edu/Wheeler/GenRel2013/Notes/GravitationalWaves.pdf But I guess I don't know what I'm talking about
  5. You keep trying to model the cosmological constant via blackholes. Your attempts with Hawking radiation won't work either. The reason being is Hawking radiation only occurs when the blackbody temperature of the Universe is lower than the blackbody temperature of the blackhole. you would need blackholes smaller than the mass of the moon for this to occur with the BLACKBODY temperature today of the Universe. At the time of surface of last scattering that small blackhole would grow not evaporate. https://en.m.wikipedia.org/wiki/Hawking_radiation
  6. No geodesics are rather tricky to derive but the related formulas are here. https://en.m.wikipedia.org/wiki/Geodesics_in_general_relativity Should be noted there is often more than 1 geodesic. Photons follow null geodesics.
  7. That's not what the Pauli exclusion principle states.
  8. There is so many mistakes in this last post I don't Even know where to start. Quite frankly in your case any reply I can give you would fall on deaf ears. Your blinded by your imagination, and lack of willingness to learn. Any ways should you choose to learn correctly the links I provided this thread is a good start
  9. I think the equation that may suit best on energy/density to curvature relations may be better seen here. [latex]R_{ab}-\frac{1}{2}Rg_{ab}=8\pi GT_{ab}[/latex] [latex]R_{ab}[/latex] is the ricci tensor,[latex] g_{ab}[/latex] is the curved by the presence of energy via the stress tensor [latex]T_{ab}[/latex]. G is the gravitational constant. R is the ricci scalar. Conceptually this equation means curvature=energy... Equation 1.1 the curvature equals energy statement is footnote 1.2. http://www.google.ca/url?q=http://www.physics.usyd.edu.au/~luke/research/masters-geodesics.pdf&sa=U&ved=0ahUKEwj25uq8qOzLAhVM4WMKHWm4Ca0QFggRMAA&usg=AFQjCNEr4WEHhcvoL-LVhqBLVIcgBRFdkQ Now as I understand the Schwartzchild metric it assumes the background vacuum =0. However I don't believe it states the curvature has zero energy/density. Without going into energy being a property lets avoid gravitons and use gravitational field energy. (Of course we could get into Komar,Bondi and ADM mass but I don't we really need to.) As it would be off the OP topic https://en.m.wikipedia.org/wiki/Mass_in_general_relativity
  10. Yeah I've had this argument before on physicsforum. The problem I've always had with the Schwartzchild child metric is the assumption of Euclidean flat being of zero energy density. At no point in the universe is there a zero energy/density. There is always the presence of some non zero field, for example the Higgs field itself. The term vacuum doesn't mean zero energy/density. Thankfully we can set the background metric as zero even if the background metric is a positive energy/density.
  11. Here is the stress/energy tensor relations to the energy density and pressure. [latex]T^{\mu\nu}=(\rho+p)U^{\mu}U^{\nu}+p\eta^{\mu\nu}[/latex] what this equation means is that as the gravitational potential increases So does the energy/mass density
  12. Even the cosmological constant has positive energy density Carrock. A void region in space away from all sources of gravitational energy has an average energy density of 7.52 *10 ^-10 joules/ m^3. You can calculate that value via the critical density formula Which correlates to roughly 5 protons per m^3. The average energy density of the interstellar medium within galaxies being a higher energy density. On average 15 times higher. As you approach a massive object the average energy/density increases via the stress/energy tensor
  13. Gravity doesn't get out the event horizon. The information of the mass of the singularity is in the gravitational field at the event horizon. Not in,
  14. If we're agreed on this part we don't need the reference
  15. Ah ok I was thinking ringdown in regard to chirp frequency. Though that would be more a ring up lol
  16. No drop this "when the event horizons touches." Gravity waves occur when there is changes in acceleration of the two Blackholes. The event horizons do not need to touch to emit gravity waves. Strain occurs in every wave. Ringdown is the number of waves and frequency of the collection of waves. It is a different formula than the strain formulas.
  17. No we're telling you that you can't draw accurate conclusions from pop media articles
  18. I didn't claim all blackholes have accretion disks Carrock. However any positive energy/density region still has mass. You don't have to read the entire reference just look at equation 43. Or section 3 of that reference. Why do you think the stress energy tensor includes [latex]\rho[/latex] Which is energy or mass density. https://en.m.wikipedia.org/wiki/Stress%E2%80%93energy_tensor
  19. Gravity doesn't get out of the event horizon. The gravitational mass information is stored at the event horizon. Kind of a difficult concept to grasp Without the math here is a simple explanation. http://physics.stackexchange.com/questions/937/how-does-gravity-escape-a-black-hole Essentially the gravitational field resides at the event horizon.
  20. Speed of light and speed of gravity are both invariant. The speed of the singularity won't change either the speed of light or gravity.
  21. Have you ever looked at the Einstein field equations? Your basing your arguments on pop media articles. You will always get the wrong impressions from these sources. For example we can never see inflation. No matter how far back we look. The mean free path of light prior to the CMB is too short. So we will never need to worry about redshift for this period. Not until we can measure the Cosmic neutrino background.
  22. You don't simplify a math formula with no math. That's just a handwave The evolution of matter and radiation over time is detailed in this equation. [latex]H_z=H_o\sqrt{\Omega_m(1+z)^3+\Omega_{rad}(1+z)^4+\Omega_{\Lambda}}[/latex] One can calculate the rate of expansion per Mpc via this equation at any function of redshift. [latex]\Omega[/latex] is a dimensionless density parameter This isn't the acceleration equations itself but you can calculate the rate of expansion in any point in the past compared to the rate of expansion today with this formula. The acceleration equation is given as [latex]\frac{\ddot{a}}{a}=-\frac{4\pi G\rho}{3c^2}(\rho c^2+3p)[/latex] This leads to [latex]H^2=\frac{\dot{a}}{a}=\frac{8\pi G\rho}{3c^2}-\frac{kc^2p}{R_c^2a^2}[/latex] a is the scale factor, p is pressure, G is the gravitational constant. [latex]\rho[/latex] is the energy or mass density. K is the curvature constant. c is the speed of light. This equation is 100% GR compatible
  23. Oh I see your still ignoring the acceleration equations. This correlates the rate of expansion with energy density and pressure. So again your lack of understanding is getting in the way
  24. Regardless though nothing can ever exit the event horizons of either BH. There is no spacetime path for mass to escape the event horizons in a BH merger. Even if those EH's are warped. The mass radiated via gravity waves must originate from Outside the event horizons.
  25. I'm asking what your referring to as ringdown. Strain and chirp frequency ringdown are two different aspects. Strain occurs every cycle but the chirp frequency determines the number of cycles and frequency rate of those cycles.
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