Mordred

yeah yeah rub it in, remind me sometime I hate graveyard shift... particularly since I'm doing lab tests every half hour grrr

One handy idea would be to read and study this low math textbook on SR. http://www.lightandmatter.com/sr/ It's a full open source textbook.

Thanks Janus, I'm a bit too busy to concentrate atm. Making too many stupid mistakes lol

I fixed that post I had the wrong observer lol. speration is literally how fast two objects are moving away or toward each other. It is not a measure of the individual speeds

spacecraft a is moving at 75c . (right) spacecraft B is moving 75c to the left. velocity of seperation from an external observer is 1.8 c however observer on craft a looking at spacecraft b will get a value less than c from observer a on the craft looking at craft b he will say craft b is moving at 96c.

its not 0.5 plus c the craft is 0.5c to outside observer at rest the speed of light is 1 c to outside observer at rest. same with observer on the ship. the length and time dilation cdifferences between observers allows c to remain invarient to all observers. The video isnt wrong you had to listen to it correctly

Let's try this minor thought experiment. You have an object emitting a wavelength due to its blackbody temperature. Observer a is moving toward the emitter so he measures a higher temperature. Observer b is moving away from the emitter so sees a lower temperature. However both measurements are dependent on the observer. According to the reference frame of the emitter the temperature hasn't changed. Now here is the question.... 1) What performs the work to cause a temperature change for observer a and b (Work must be performed to change the energy level)? (The work is needed on the signal between emitter and observer) it does correlate. You might not see how but is does. Try to answer the puzzle and you may better understand one of the problems with defining conservation of energy in the universe scale

Yeah gotcha, I looked at the reference. The reference papers are modelling DM as being ultralight. I noted the references are back on 2000. They are based partly on quintessence. Or at least the papers include quintessence. If I'm not mistaken it's a counter argument for hot dark matter rather than cold dark matter. The ultralight mass would correspond to that. Here is one of the reference papers for that wiki page http://arxiv.org/abs/astro-ph/0004332 Judging from your math skills and knowledge. As well as attention to detail. I would hazard a guess that your working on a thesis paper. Showing various modelling of DM is a good step. I'm assuming based on the above that you will probably include the fermionic sterile neutrinos idea into your paper If I'm correct let me know and I'll go through my database of articles for reference materials

The stress energy/momentum tensor. The graviton would be a gauge vector boson. What many don't realize is the photon as a mediator (gauge vector boson) isn't precisely the same as a photon the particle. In so far as it's akin to a virtual photon. (Off shell). Another common misconception is thinking of particles as little bullets. Particles are excitations in a field. Here is a good coverage. http://www.google.ca/url?sa=t&source=web&cd=15&rct=j&q=particles%20as%20excitations%20of%20fields&ved=0ahUKEwjTm_va2a7LAhVW-mMKHZ3MDuYQFghWMA4&url=http%3A%2F%2Farxiv.org%2Fpdf%2F1204.4616&usg=AFQjCNGvQ8n6ZVIKYjFHcDC_yoFRbWmNkQ https://en.m.wikipedia.org/wiki/Force_carrier

When you describe a problem in relativity it's a needed step to be clear on the observer. Just an fyi

see my edit last post I caught that question while you were posting

No, you probably didnt see my post above lets take another example spacecraft is moving at 0.9 c fires a rocket at 0.9c as seen from spacecraft. An external observer will measure 0.9999494975001263 c no matter how close the rocket and craft is to c the addition will always be less than c a laser always travels at c in a vacuum to all observers, observer in the craft will see the laser move at c and so will an external observer. yes an external observer will still measure the craft at 0.5c

if ship a travelling at 0.5 c fires a rocket at 0.5 c as seen from the ship the rocket will be seen to move at 0.8c. from an external observer. use your relativistic velocity addition formula https://en.wikipedia.org/wiki/Velocity-addition_formula

Why can't you accept option C? C: we do not have enough conclusive evidence to fully define conservation of energy on the scale of the Universe. More research is underway David you keep trying to force an answer on a question that cannot be conclusively answered. If a poster says a is correct another poster can argue b is correct. So please try to understand their is no conclusive answer. Let's try this minor thought experiment. You have an object emitting a wavelength due to its blackbody temperature. Observer a is moving toward the emitter so he measures a higher temperature. Observer b is moving away from the emitter so sees a lower temperature. However both measurements are dependent on the observer. According to the reference frame of the emitter the temperature hasn't changed. Now here is the question.... 1) What performs the work to cause a temperature change for observer a and b (Work must be performed to change the energy level)? (The work is needed on the signal between emitter and observer)

Yes I know the spin zero correlates to scalar particles. My question is why are you considering dark matter as a scalar quantity? Ah didn't see the portion where your counting as a sterile neutrino. Question answered Except according to your references sterile neutrinos has a spin 1/2 statistic which is not scalar. Nor is it a boson but is a fermion Which means you should be using the Fermi-Dirac statistics for dark matter not the Bose-Einstein statistics check spin statistic reference 4

its [latex]3/2 R_s[/latex] where [latex] R_s[/latex] is the Schwartzchild radius. Yeah I mean't EH not the photon sphere. Overtired lol

I doubt it, butif your interested in a historical reprint of SR. http://www.gutenberg.org/files/30155/30155-pdf.pdf: "Relativity: The Special and General Theory" by Albert Einstein Its a rather good read

You wouldnt see gravity emitted from inside the BH, The mass is lost from the EH photon sphere outward. The only way a BH can lose mass is via Hawking radiation. Think of it this way the information of the mass inside the EH is stored at the photon sphere.

trust me the Nbody codes is a bugger to correlate to the Einstein field equations. However Strange is correct, the paper I posted earlier this thread has some of the applicable mathematics. I have two N-body textbooks and even though I know the formulas involved. I can't even get past chapter one of either book and I can program in over 20 programming lanquages. (just a side note lol) http://arxiv.org/pdf/gr-qc/0309058v2.pdf

No you don't recall correctly.( Or your not understanding correctly) Redshift isn't directly related to blackbody temperature. The emitter wavelength is related to the blackbody temperature via Weins displacement law. https://en.m.wikipedia.org/wiki/Wien%27s_displacement_law The redshift affects the wavelength due to the distance change from the time the wavelength is emitted to the observer. It's change is a measure of the amount of expansion that has occurred. [latex]z=\frac{\lambda_{emitter}}{\lambda_{observer}}[/latex] Z=1100 represents the amount of expansion and is used to determine the proper distance.

Hoyle tried working on a different model in his later years not the steady state. what do you think time line on this link you previously mentioned means? http://www.physicsoftheuniverse.com/topics_bigbang_timeline.html it means that as the temperature drops from 10^19 Gev due to expansion different particle mixtures drop out of thermal equilibrium. This process is what led to the CMB. We not only measure the CMB temperature we also measure its mixture of elements. This mixture percentage matches what is predicted by the BB model. Not Hoyles steady state. "Recombination/Decoupling, from 240,000 to 300,000 years: As the temperature of the universe falls to around 3,000 degrees (about the same heat as the surface of the Sun) and its density also continues to fall, ionized hydrogen and helium atoms capture electrons (known as recombination), thus neutralizing their electric charge. With the electrons now bound to atoms, the universe finally becomes transparent to light, making this the earliest epoch observable today. It also releases the photons in the universe which have up till this time been interacting with electrons and protons in an opaque photon-baryon fluid (known as decoupling), and these photons (the same ones we see in todays cosmic background radiation) can now travel freely. By the end of this period, the universe consists of a fog of about 75% hydrogen and 25% helium, with just traces of lithium. I also posted you several reference papers that detail BB nucleosynthesis. Here this wikilink has a better timeline https://en.m.wikipedia.org/wiki/Graphical_timeline_of_the_Big_Bang https://en.m.wikipedia.org/wiki/Chronology_of_the_universe

I really wish you would actually study the models your defending. The steady state model required matter creation at a rate to keep the average density CONSTANT. A constant density means a constant temperature. We know for MEASURED FACT this isnt true. A constant energy density as Strange pointed out to you the CMB would never have occured. However you choose to ignore this detail. Even Hoyle himself admitted his model was wrong. So why would you claim it is right.? Hoyles model is not the only one that has matter creation, or mass creation. However you obviously don't understand that mass and energy are interchangeable. NOT on a unit per unit basis. but via a ratio. The reason I pointed out the zero energy density model is the model starts with ZERO energy and builds a universe, Yet maintains conservation of energy. Via potential energy vs kinetic energy. Ive continously pointed out how You model conservation of energy DEPENDS on the metrics in use and how you define the state your modelling. Youve been shown numerous links that tell you it doesnt work in an evolving spacetime accurately and its more for localized systems. Ive repeatively mentioned that the FLRW metric doesnt handle conservation of energy well due to be 100% conpatible with GR which doesn't particularly cover conservation on a Universe scale well. Yet you continously insist that this means the Hoyle model is correct when you obviously never looked at why the Hoyle model was proved wrong in the first place. here is an explanation of matter creation https://en.wikipedia.org/wiki/Matter_creation we can create matter in the lab why shouldn't the universe be able to create matter?

KE doesnt contribute to rest mass as its a particle at rest. so momentum is zero. This is called nowadays the invariant mass. Inertial mass will increase with momentum via the formula Swansort provided. Here is the formulas the kinetic energy of an object is the energy that it possesses due to its motion. https://en.wikipedia.org/wiki/Mass_in_special_relativity the formula Swansort provided is the total energy formula. Don't confuse these equations with KE though the relativistic KE equation is [latex]E_k=\sqrt{p^2m^2+m^2C^4}-mc^2[/latex] notice the last formula subtracts the invariant (rest)mass from the total energy-momentum equation invariant mass is given by [latex]E=m_oc^2[/latex] the total energy formula gives you the relativistic mass which most books and physicists no longer like using that term. As its often too subject to misunderstanding "The concept of "relativistic mass" is subject to misunderstanding. That's why we don't use it. First, it applies the name mass - belonging to the magnitude of a 4-vector - to a very different concept, the time component of a 4-vector. Second, it makes increase of energy of an object with velocity or momentum appear to be connected with some change in internal structure of the object. In reality, the increase of energy with velocity originates not in the object but in the geometric properties of spacetime itself." https://en.wikipedia.org/wiki/Relativistic_mass#Relativistic_mass

Are you basing your dark matter scalar particle composition on dark matter being a flavor of neutrinos? Ie neutralinos or sterile neutriinos ? Isn't that model dependant? Ie S0(10) MSSM something along these lines? http://arxiv.org/pdf/1306.4954v1.pdf If you could can you post a better peer review detail on which specifics your following for the dark matter scalar particle composition. Part of the reason I ask is your particle number density for DM is nearly the same as the number density most textbooks give for the number of elementary particles 10^90 particles.

They have a decent coverage without being too intense into GR metrics. If you look at my signature the webpage there has some good study material. Including a couple of free textbooks. Another older textbook that's handy for a first read is Weinburgs "First three minutes" it's a bit outdated but still excellent on the basics