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Mordred

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Everything posted by Mordred

  1. Roflmao you are coming a long way since your first post
  2. Basically accurate all forms of influence can be described by geometry Correct
  3. As to the last calculator that's the lightcone calculator for the expansion history of the universe. I helped write the user guide and tutorial. Jorrie is the programmer. It can use the FLRW metric to show any distance measures in Cosmology expansion. As well as plot it in the lightcones and world lines. Starts at CMB forward and can plot 88 billion years into the future.
  4. Distance calculators is no replacement to knowledge. Particularly when you need to adapt a formula
  5. Use the rules on your Schwartzchild image, practice the conversions so you don't need to think about them. Start with the examples on that link. In your other thread I posted a calculus article. There is examples there. Its best to eat the Apple one bite at a time. As far as exact conversions, there is more exacting coordinate systems. Though in the angles they get extremely precise. Degrees minutes seconds for example. To be honest I can't recall a single formula that uses tan
  6. You need to apply the polar to Cartesian conversions I've posted. See the math is fun link the conversion rules will answer your question. ( when do you choose to use sine,sineh cos and Cosh?). See link. Now your getting it.
  7. Linear vectors are more often done in Cartesian. Ie a constant force applied in a vector direction. Look at the metric to describe the flat euclidean plane. Positive x is typically north. - X south +y east -y west A helpful visualization tool Is look at how polar coordinates is used to map locations on the Earth.( Polar coordinates is common in navigation) We could map locations on Earth in Cartesian coordinates but it's more inconvenient to do so. Here is a basic polar to Cartesian coordinate conversion link http://www.mathsisfun.com/polar-cartesian-coordinates.html
  8. The collateral and lateral terms are polar coordinates. Angular momentum is often done in the colateral coordinate for example. X,y,z,t are Cartesian coordinates. I recommend studying the two coordinate systems in detail and look at the conversions between the two. Inertial frames of reference can use either system so knowing how to convert between the two Is an invaluable skill. This will also help you connect the sine and cos rules as they are involved in the conversions. Curvature influences are more often than not use the polar coordinate system. (In some cases one assigns the north direction of influence.).sine waves is a good example. In this case the curve of a sine wave is more convenient in polar coordinate change than doing the coordinate change in Cartesian coordinates. ( spherical objects and interactions are typically done in polar coordinates)
  9. Ah no problem thought ya did The relationship is shown in the stress energy tensor http://en.m.wikipedia.org/wiki/Stress%E2%80%93energy_tensor http://www2.warwick.ac.uk/fac/sci/physics/current/teach/module_home/px436/notes/lecture6.pdf
  10. Have you looked at the calculator? You can graph the expansion history distance now and distance then Here this might be clearer http://www.ifa.hawaii.edu/info/press-releases/flows/ http://arxiv.org/abs/1306.0091. This is local data group The others I located require software example http://supernova.lbl.gov/union/ I'll keep looking
  11. Lets put it this way your learning far more due to your listening and applying what we explain. Some posters no Matter how you correct or teach them never learn and ignore anything that conflicts with their ideas. Even when the idea is utter nonsense Speaking of studying. I'm not sure I posted this excellent aid for you. It's extremely handy though math heavy http://www.blau.itp.unibe.ch/newlecturesGR.pdf"Lecture Notes on General Relativity" Matthias Blau it's a little over 900 pages but it covers numerous metrics used in GR
  12. http://arxiv.org/pdf/astro-ph/0402278v1.pdf[/url Here is a dissertation specifically on expansion. This calculator will allow you to see the expansion history yourself. It can calculate redshift distance now distance then evolution of the Hubbles sphere and observable universe etc Etc open column selections to choose. Number of steps for row control. http://www.einsteins-theory-of-relativity-4engineers.com/LightCone7/LightCone.html http://cosmocalc.wikidot.com/lightcone-tutorial http://cosmocalc.wikidot.com/lightcone-userguide As far as my proving the most proven model to observational evidence model to date LCDM. There is no need for me to prove the concordance model. There is tons of supporting evidence. The Planck datasets are in strong agreement with LCDM http://www.cosmos.esa.int/web/planck/publications tons of datasets there for ya
  13. And your point? The wording comes from trying to correlate a positive energy density that gives a negative vacuum. Here is the simple related FLRW metric for that term. [latex]w=\frac{\rho}{p}[/latex] The stress energy tender has a similar relation in its tensor matrix. In other words it's describing negative vacuum as replulsive gravity When you think of an influence such as dark energy in terms of a pressure influence it removes the mystery on how it's influence works. We still don't know the cause but in terms of pressure its easily understood. I've posted numerous posts stressing the importance of thermodynamics in the FLRW metric and EFE. If you really want a solid understanding of cosmology. Study the ideal/perfect fluid laws. It will also help understand nucleosynthesis.
  14. I'll see if I can dig up some of his earlier papers from my archives later on. No I heard the analogy before and studied what they meant by it.
  15. Yeah I read his analogies before. Keep in mind he's simply stating similarities between gravitational pressure influence and other pressure influences. He is not stating gravity itself is repulsive. Nor is he claiming anti gravity. Just anti gravity like influence There is validity in the correlation. I prefer to relate to the dynamics in terms of pressure distributions Guth's false vacuum model for inflation is a higher energy region false vacuum tunneling to the true vacuum (lower energy region). Though he was involved in numerous inflation models trying to solve runaway inflation.
  16. I never trust pop media vids. I'll stick with the metric and textbooks
  17. Short answer all particles exert pressure via interactions. Matter exerts effectively zero pressure. Then the acceleration equation correlates the positive pressure contributors and the negative pressure contributors. (Positive vs negative vacuum). Cosmological constant being positive. This relationship also determines the curvature constant. http://cosmology101.wikidot.com/universe-geometry Page 2 http://cosmology101.wikidot.com/geometry-flrw-metric/ These two articles will also help 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 There is considerable different between pressure and gravity Though gravity does exert pressure via the stress energy tensor it isn't the only pressure contribution to consider in the acceleration equation.
  18. To understand why you need to look at the acceletion and deceleration equations, curvature constant and the equations of state for the various contributors. Radiation,matter and the cosmological constant. The FLRW has ideal gas pressure terms you need to look at. http://en.m.wikipedia.org/wiki/Friedmann_equations The acceleration equation is on this page http://en.m.wikipedia.org/wiki/Deceleration_parameter
  19. Imatfall you were looking for Dr Chinese website. http://www.drchinese.com/Bells_Theorem.htm Good reference site covering Bells theorem
  20. What spooky repulsive gravity thing? Gravity isn't repulsive. No one knows which of the 70+ good fits to observation inflation models is correct. Some models are thermodynamic phase transitions. Some involve the Higgs field. Others involved the inflaton. While others the curvaton. My personal bet is on Higgs related thermodynamic phase change via the seesaw mechanism Don't mean I'm right.
  21. Of course not the image you showed is no where near precise. It's simply a tool to aid understanding not an exact map. Its simply showing that galaxies are closer together the further you look back in time.
  22. The space foam is a descriptive once used to describe the quantum fluctuations of the quantum oscillator in QM. GR doesn't have space foam. This is where the debate is space smooth or lumpy came into play . Side note the process I described leads to 120 orders of magnitude to much energy. So either QMs quantum oscillator is wrong or something unknown is suppressing the energy. It's why you don't see it mentioned much anymore
  23. How many times have you heard me say space is geometric volume. According to QMs zero point energy it's never empty. You didn't catch my edit. V is frequency in QM.
  24. Did he also tell you that energy and momentum can also generate gravity lol say hi back been awhile V is frequency h is the planck constant
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