-
Posts
10028 -
Joined
-
Last visited
-
Days Won
37
Content Type
Profiles
Forums
Events
Everything posted by Mordred
-
Will this ever reach us? (question about expansion)
Mordred replied to ccwebb's topic in Astronomy and Cosmology
yes expansion is 67.3 km/s/Mpc, your object is moving 894 Km/sec which is faster than the rate of expansion -
I don't believe your even looking at the links I'm providing. Perhaps you'll at least read the non math portion of this one. As it does correlate your bits to entropy information. Quantum information theory of entanglement and measurement http://arxiv.org/pdf/quant-ph/9605039v2.pdf "Quantum information theory is the study of the achievable limits of information processing within quantum mechanics. Many different types of information can be accommodated within quantum mechanics, including classical information,coherent quantum information,and entanglement" here is a dissertation. http://cds.cern.ch/record/476522/files/0011036.pdf The descriptive you supplied is already explained in this dissertation
-
then what information are you describing????? Define information according to your model. http://profmattstrassler.com/articles-and-posts/relativity-space-astronomy-and-cosmology/black-holes/black-hole-information-paradox-an-introduction/ http://taper100.hubpages.com/hub/The-Black-Hole-Information-Paradox-Explained http://www.dummies.com/how-to/content/string-theory-and-the-black-hole-information-parad.html http://arxiv.org/pdf/1005.2739v3.pdf "Quantum mechanics emerges from information theory applied to causal horizons." looks to me that GR metrics do apply as well as QFT.
-
Ok lets start with curvature, I wrote and article on it in my webpage, see the cosmology101 signature link. Read the Universe geometry article. The metrics is done according to the FRW metrics, much of the work is referenced to Barbera Ryden's work. Simply as her methodology is one of the best and easiest handling's of the FRW metrics in relation to universe geometry I've come across. I've read and own over 16 Cosmology textbooks, her method is still the tops for that. I have some metric corrections to make on the Redshift and expansion article, those corrections is on defining proper vs conformal and com moving distances. However that article is also a good read. Overall its accurate. There is numerous other article you may be interested in. The only two articles I wrote are under site links heading. The rest are all professional papers. Once you read the universe geometry article you will understand how the torus for example is only definable as homogeneous and isotropic at certain and specific locations. The universe according to WMAP and PLANCK data is close to flat or rather the universe geometry according to their observations an measurements of the CMB show the geometry as close to flat. Reading your last post more accurately, I would recommend studying the general relativity article by Mathius Blau. http://www.blau.itp.unibe.ch/newlecturesGR.pdf "Lecture Notes on General Relativity" Matthias Blau This article however is math intense, but it shows all the various treatments of GR according to geometry relations with matter Unfortunately I don't have any good articles covering the holographic principle. The expression "If you wish to change the rules " means that you need to correctly understand the models your trying to refer to and adapt to your model. You simply cannot properly do so unless you can properly explain the relations to those models. Unfortunately in order to do that you have to relate to their metrics. A simple verbal descriptive is never sufficient. For example which GR metrics does your model comply with ? now you keep referring to the holographic universe, this is a string theory model...... The holographic principle and its realization in string theory through the AdS/CFT correspondence have helped elucidate the mysteries of back holes suggested by Hawking's work and are believed to provide a resolution of the black hole information paradox. for that you can study the "Fields" article, it has the Ads/CFT metrics covered inside however its 885 pages long http://arxiv.org/abs/hepth/9912205 : "Fields" - A free lengthy technical training manual on classical and quantum fields
-
I've spent a few years collecting good articles to teach online students Cosmology, according to textbook standards. Here is a collection of articles 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://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/1301.0219What's in a Name: History and Meanings of the Term "Big Bang" Helge Kragh http://arxiv.org/pdf/0906.1442v1.pdf Is it possible to see the infinite future of the Universe when falling into a black hole? Training (textbook Style Articles) 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 http://www.gutenberg.org/files/30155/30155-pdf.pdf: "Relativity: The Special and General Theory" by Albert Einstein http://www.blau.itp.unibe.ch/newlecturesGR.pdf "Lecture Notes on General Relativity" Matthias Blau http://arxiv.org/abs/1201.4598 "Introduction to Loop Quantum Cosmology by Abhay Ashtekar http://arxiv.org/abs/hepth/9912205 : "Fields" - A free lengthy technical training manual on classical and quantum fields Historical article links http://www.astrosurf.com/luxorion/hubble-law-redshift1929.htm Reprint of one of Hubbles papers. http://www.marxists.org/reference/archive/einstein/works/1910s/relative/relativity.pdf An authorized reprint of Einsteins Special relativity paper. http://apod.nasa.gov/diamond_jubilee/debate20.html The "Great debate of the 20's" jubilee reprint article available http://www.drchinese.com/Bells_Theorem.htm Good reference site covering Bells theorem. http://www.intechopen.com/download/pdf/41230 good historical coverage of many of the key figures in Cosmology history http://arxiv.org/abs/1302.1498 " “The Waters I am Entering No One yet Has Crossed”: Alexander Friedman and the Origins of Modern Cosmology" written by Ari Belenkiy http://arxiv.org/pdf/1212.5499.pdf "The Contribution of V. M. Slipher to the Discovery of the Expanding Universe" by C. O’Raifeartaigh http://www.gutenberg.org/files/17384/17384-pdf.pdf "foundations of geometry" David Hilbert
-
no not really an accurate way to describe it lol. A particle in QM has both pointlike properties and a wave function. If you took a laser beam and fired it at a slit it would have a dispersion pattern that can only be generated by a frequency wave. If the particle didn't have a wave function it would consistently hit the same point. Particles are described by its spin, momentum and energy. Energy has a mass equivelence. However detection of particles is done by shooting electrons or other electromagnetic medium at a particular medium. The electons then have a correlating dispersion pattern due to the interaction with that particle. From this dispersion pattern we can infer the properties of the particle itself, as well as the structure of the atom for example. The pointlike properties is a descriptive of the region of highest energy density. Often referred to as a packet. We cannot describe how much volume a particle has, we simply have no means of directly measuring volume of a particle. They are too small and move too fast. To work around this problem QM developed its metrics upon the information we can successfully collect. Spin, momentum, and energy. Frequency is a property of its momentum. Spin is due to the configuration of quarks and gluons that make up the particle. Google eightfold way. http://en.wikipedia.org/wiki/Eightfold_Way_%28physics%29 A good textbook covering particle physics is Inroductory to Elementary particles by David Griffith, he also has a good introductory book on quantum physics. http://www.amazon.ca/Introduction-Elementary-Particles-David-Griffiths/dp/3527406018, you can see the other books on the same page
-
Whats past the singularity of a black hole?
Mordred replied to kirbsrob's topic in Astronomy and Cosmology
Actually quantum gravity also has trouble describing the singularity problem, there is one particular descriptive of the singularity problem I always liked. "However, because gravity is geometry in general relativity, when the gravitational field becomes singular, the continuum tears and the space-time itself ends. There is no more an arena for other fields to live in. All of physics, as we know it, comes to an abrupt halt. Physical observables associated with both matter and geometry simply diverge, signalling a fundamental flaw in our description of Nature" Loop qunatum cosmology has some hopes, so does string theory. Its a wait and see lol. LQC managed some metrics that removed the BBN singularity. I haven't seen how they tackled the BH singularity. Although they have a recent paper called Planck stars Loop Quantum Cosmology : A status report http://arxiv.org/abs/1108.0893 Planck stars http://arxiv.org/abs/1401.6562 this article shows some strong possibilities and is still heavily being discussed, Citations are currently developing though some are already available including counter papers. "A star that collapses gravitationally can reach a further stage of its life, where quantum-gravitational pressure counteracts weight. The duration of this stage is very short in the star proper time, yielding a bounce, but extremely long seen from the outside, because of the huge gravitational time dilation" -
There is an expression you should try "If you wish to change the rules you should first understand the rules" First off information of a particle in QM is a particles spin, momentum and energy. So a new model needs to be able to comply with that. Your model alters the behavior of time, so now you have to redefine the scale factor of the FRW metric. A multi spacial dimension of influence outside of the 3+1 dimensions described by the Einstein field equations and FRW metric would redefine those very metrics as well. String theory does so, however shows the metrics as to how it is compatible with the previous priori. Any metric ued must be compatible with QM, the EFE and the FRW metrics. These metrics are fundamental to any descriptive of the Universe. All professional model proposols use various mean to make their model compatible with the priori I described. Including the universe within a black hole models. Some are merely a mathematical misinterpretation of the Scwartzchild metric. Poplowskii adds a new term to replace the comological constant (torsion). My advise is study the FRW metric and Einstein field equations. Learn the basics first, once you do you will understand why your model won't work. By the way learning comology from the internet is a very bad idea. I recommend picking up a textbook. "Introductory to Cosmology" by Barbera Ryden is a nce beginner textbook with relatively easy math requirement. She sticks primarily to the FRW metric which people find easier to learn than the Einstein field equations. Scott Dodelson's Modern Cosmology takes more time to learn as it is written primarily using the EFE.
-
see here is the problem, this Is your theory. I teach standard cosmology according to the concordance model. When your theory reaches a professional peer reviewed paper. I'll happily look it over, til then good luck. by the way what you described makes absolutey no sense and I have a PhD.
-
Just to add some information, there is 3 major categories of redshift to consider in Cosmology. Doppler shift =motion, gravitational redshift (redshift due to particles falling into or climbing out of a gravity well) and cosmological redshift-whichis due to expansion. Each form of redshift has its own mathematical formula and each must be considered and accounted for
-
To add some key points. First of to describe how stars and large scale structure formation started you must understand the thermodynamics involved. So lets start at the end of inflation. Or rather at the reheating phase at the end of inflation. During this time the temperature is too hot for stable recations to occur. Any reaction, quickly destabilizes into the reverse reaction. This is described as thermal equilibrium. The ideal gas laws decribe the relations. However the simple forms are not applicable. To describe fermions you need the fermi-dirac distribution formula, for bosons you need to use the bose-Einstein distributions. So photons which is it own anti particle and is a boson with a spin of one. Has an entropy of 2, and its distributions are described by the Bose_Einstein distributions. Now inflation reheating didn't reheat all the volume of space at the same time. Some regions reheated slighly later. This caused regions of anistropies. The cooler regions will have particle species drop out of equilibrium faster than other regions. Gravity starts to take hold of the matter forming in the cooler regions expanding the anistropy regions. As the volume of the universe continues to increase. A rough order is photons, neutrinos(including electron),protons, neutron. Once protons and neutrons drop out of equilibrium hydrgen, lithium, deuturium and lithium can start to form. They collect in the cooler regions first. Dark matter i also an early phase and contributor but its debatable how early it drop out of equilibrium. Where the cooler regions are gravity continues to collect the available plasma. these two articles cover this however be prepared for intense math. hydrogen and helium formation starts at chapter 5 of the second article which also covers BBN big bang nucleosynthesis. 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 big rip has largely been discounted, The simple reason is that the energy-density of the cosmolical constant per m3 is miniscule compared to the strong force and gravity. Its easily overpowered. As the cosmological constant is in fact constant, it will remain easily overpowered. Instead were heading towards heat death (big chill)
-
good question. The hot dense state of the big bang model prior to inflation was in thermal equilibrium, I'll simply start with the quark-gluon plasma state. Prior to being able to collapse, inflation occured. This effectively and suddenly increased the volume of the universe by roughly 60 e-folds. Exact value depends on the model of inflation. This caused a sudden cooling due to a sudden increase in volume. However towards the end of inflation there is also a significant reheating phase. This places the universe back into thermal equilibrium however over a larger volume. No one knows the mechanism of the comological constant, however it continues to expand the universe. Now the cosmological constant keeps the universe expanding rather than gravity causing a collapse
-
Question about mass density of the universe
Mordred replied to michel123456's topic in Astronomy and Cosmology
This statement is a bit misleading, The universe expansion and contraction is determined by the energy-mass density (positive pressure) of matter and radiation and the cosmological constant. (negative pressure). The corresponding energy-density relation is determined by the equation of state. This relation also determines the universes overall geometry. This is essentially a geometric description of the universes overall energy-density distributions compared to its critical density. As the universe expands. The energy density of matter reduces, however the cosmological constant does not reduce (it remains constant). -
fixing this link http://arxiv.org/abs/1301.0219 whats in a Name: History and Meanings of the Term "Big Bang" Helge Kragh no problem it is non commercial so I will add it to my signature just as oon as I find out how lol
-
Alright I tried following this topic and quite frankly I haven't seen one decent answer. Instead I've read numerous arguments lol. However being that I am new here I will address the original question. The universe inside a whitehole/blackhole is invalid, it was a model proposal by Poplowskii. The model uses spin and torsion to try to account for a homogeneous and isotropic universe, however it fails to account for early large scale structure formation. However that doesn't stop him from working on it lol... http://www.nikodempoplawski.com/publications.html http://arxiv.org/abs/1007.0587 Not too many professional cosmologists think too highly of his work. Although his metrics are kind of interesting. I read tons of cosmology articles and I can say with confidence that his work is rarely cited. -particularly since his models is also a counter to inflation models. Inflation has too strong of supportive evidence, particulary since they may have found evidence of gravity waves in the CMB. The planck papers also support inflation models with a higher observation agreement towards the single scalar models with low kinetic term. The best fit to observations is the LambdaCDM model. Which is essentially the hot big bang model with cold(non relativistic) dark matter. The hot big bang beginning does not describe the beginning of the universe, it only describes a hot dense state from 10-42 sec forward. The early timeline is based on our understanding of symmetry breaking temperature correlations of particle physics. Essentially when a particle species drops out of thermal equilibrium. Prior to that time our knowledge of physics breaks down. Anyways another key note on blackholes, they do not feed at consistent rates, so if we were inside one. Shouldn't we also measure varying energy-density distributions in the CMB or within the IGM (Intergalactic medium)? We don't overall the universe is homogeneous and isotropic (Homogeneous no preferred location)(isotropic no preferred direction). This is also why the big bang is not the result of some explosion from some infinitely dense god particle. Multimedia loves to show that analogy lol. The misiscule point described is the start of our lightcone (region of shared causality) In simpler words our observable universe. We do not know if the universe is finite or infinte. We have no means of measuring beyond the cosmic event horizon, so we make no statements about that region, other than we have no reason to think it will be any different than our observable. Now here is some related articles 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/1301.0219What's in a Name: History and Meanings of the Term "Big Bang" Helge Kragh http://arxiv.org/pdf/0906.1442v1.pdf Is it possible to see the infinite future of the Universe when falling into a black hole? my website also has links to professional articles (Non pop media, peer reviewed articles) designed to teach cosmology to the new student, feel free to browse the site, it also includes some textbook style (free Official open source articles) link removed