Mordred

On the subject of the OP. Here is a future test on The equivalence principle being launched in Apr 2016. http://www.zmescience.com/science/physics/microscope-satellite-mass-equivallence-0423423/ In case it wasn't mentioned Gravity Probe B. http://m.smh.com.au/technology/sci-tech/nasa-confirms-einsteins-theory-of-relativity-20110505-1e9et.html

Ok that's roughly what I figured. Lets explain spacetime curvature. First let's set some ground rules. You cannot measure gravity, mass etc on an empty volume. Nor energy. You must have something to measure. space is nothing but volume, that happens to have the standard model particles residing in it. So a gravitational field is a field of particles that we measure the influence of gravity upon. Now we have to set a baseline. Well a good baseline is the average mass/energy density of the universe. Exact value isn't important. We will use the Schwartzchild metric which sets this value as zero to start. One final detail. Energy density of a collection of particles can cause pressure along with the particles kinetic energy. Now the Einstein field equations has something called the stress/energy/momentum tensor. You heard the expression "mass tells space how to curve , space tells mass how to move". Well there is a nice formula that explains this. [latex]T^{\mu\nu}=(\rho+p)U^{\mu}U^{\nu}+p\eta^{\mu\nu}[/latex] [latex]\rho[/latex] [latex]T^{\mu\nu}[/latex] is the stress tensor. The subscripts are coordinates. p is pressure [latex]\rho[/latex] is energy/mass density. https://en.m.wikipedia.org/wiki/Stress%E2%80%93energy_tensor So in the presense of mass there is an influence on the gravitational field. (Particles that reside in that locality). That influence gets greater the closer to the source of mass. voila spacetime curvature due to mass. Which is nothing more than the distribution curve measuring the influence of gravity upon the particles residing in a given volume. It was never meant to state that spacetime was it's own fabric or mysterious substance

Newtonian gravity isn't wrong in everyday situations. It just doesn't work well in curved spacetime. However in Euclidean space it's just as accurate. I'm still waiting on what you understand as curved spacetime. By the way every aspect of relativity has been tested. Though length contraction being the least. Afiak

I have to ask Bjarnes Do you fully understand what is meant by curved spacetime? Or is your visualization based upon the common misbelief that space has a fabric like substance that can be curved stretched etc. You would be amazed how few understand what spacetime curvature really represents. (Those same people are usually the ones that feel relativity is wrong). So please don't be insulted, just describe what you think spacetime curvature is describing.

This would be true only if there is no expansion/contraction. However at no point in the Universe history has it not been expanding. Different rates of expansion but expansion nonetheless.

Roflmao

No no no. A billion light years is a unit of distance. Not years. During this time the universe has been expanding so the distance of the light path will be GREATER than 13 billion years

It is published information in the Planck 2015 dataset. The other reason is any good textbook discusses redshift and it's influence upon redshift. Sachs Wolfe effect for example takes advantage of those influences to give us greater detail on expansion as well as the CMB. In Matt Roose "Introductory to Cosmology" the axis of evil" was explainable before the Planck dataset was released. In textbook terminology it's called dipole anisotropy. Matt Roose has a good chapter on it. Any major dataset published will include the calibration data. Most ppl that read it tend to ignore this info. Rather dry and boring I guess.

Initial redshift will give us an estimated distance. Keep in mind both those articles I wrote several years back. Let's take that star example again. If Say that star was moving away from us extremely fast. One would think it's further away than what it really is. If it was moving toward you at the same speed you would think it's closer than it really is. (Based solely upon redshift measurement) I'm almost hesitant to answer this part given you tendency to get distracted. Yes you will measure different redshift to a certain degree at various points. Those variations are due to other redshift interference. (NO THIS IS NOT BIG NEWS). Any physicist working on the data knows what type of influences can be involved. So they will take other data to filter out those influences. Remember the Planck 2012 Right hemisphere "axis of evil". Where one axis appears hotter than the other.? That was simply due to not having enough filter to compensate for Earths movement. Calibration on the Planck data is published in their papers including the calibration settings. Several of their papers deals just with their calibration.

You can't rely on just redshift. Let's say I want to measure a star. First I know hydrogen gas a specific spectrum on the Rayleigh scale. So from this I can estimate the frequency of the emitter. Good so far now let's follow the light path from that star to Earth. First question to answer, is that light path a straight line? Surprisingly enough due to universe geometry influence the path can be curved. Just as spacetime curvature can alter the path of a light Ray. So we must compensate for this change. (Distance change in light path) 2) did the light path enter a gravity well? This causes gravitational redshift/blueshift. 3) what's is the stars movement compared to our. (Doppler shift) You cannot from measure alone distinquish cosmological redshift, from gravitational redshift or Doppler shift. You require further details and measurements to seperate how much each has influence upon your light Ray. For these reasons distance measurements requires mountains of data to fine tune them. They require multiple methods. Parallax being one of them. Here these will help. Site Articles (Articles written by PF and Site members) http://cosmology101.wikidot.com/redshift-and-expansion http://cosmology101.wikidot.com/universe-geometry

David you really need to grasp a few concepts. First redshift is only calculatable if you know the emitter frequency. (For this we note the Rayleigh scale on specific elements) Secondly there is several types of redshift. (Cosmological, gravitational, Doppler). Thirdly we must filter out our own environment influences ( galaxy, solar system and planetary movement). Local radiation etc. It took years of expiremental research to correlate the average redshift in the CMB. It took years of experimental research to develop the redshift formula. (Previously it was hypothesized as "tired light" or alternatively referred to as "spectral shift" As mentioned you cannot separate theory and evidence. Evidence is a fundamental part of a working theory This has more to do with how early can galaxies form than the CMB itself.

No they don't band the evidence to support theory. If evidence shows up that proves the theory wrong they rethink the theory. This has happened to me several times lol. I develop a hypothesis, work on the math. Look for evidence and experimental data. If I find data that conflicts I try to explain it with my hypothesis. If I cannot then I know something is wrong. So I try to figure out how wrong my hypothesis is. (Note at no time did I consider the above a working theory). One of the steps to test a theory is a diligent effort to prove that theory wrong. Otherwise you will never develop a strong long lasting theory.

Correct couldn't have explained it better myself

Yeah I am familiar with that thread. I'll take the word of professional peer review articles over a forum discussion any day. Particularly since Pioneer anomoly has been discussed to death in other forums I'm also a member of. A forum is a learning and teaching aid. One doesn't change a theory via a forum. You would need to publish in a peer review to hope to do that (Anyways this is off topic). Do you have further questions on measuring satellite distance,?

Just to note if you plan on tackling relativity. You better have conclusive experimental evidence. I saw the thread that was locked. For lack of such. The Pioneer anomoly for example was figured out to be caused by anisotropic radiation loss due to the crafts own heat. You can get the paper in the reference on this page. https://en.m.wikipedia.org/wiki/Pioneer_anomaly Just a side note forums are battered with posters that assume something is wrong, believe they have the solution but can't even do the mathematical side of the theory they are fighting against.

No matter how confident we are in any theory the scientific method always considers some error. No theory is ever claimed 100%. So we continue to improve our confidence in a theory.

You know you could look at the numbers with the lightcone calculator on my signature. It has redshift, scale factor and various key distances built into it. You can even graph the results. PS it will even show expansion roughly 88 billion years into the future assuming the physics of the universe doesn't change However you might enjoy. http://arxiv.org/abs/astro-ph/?9905116"Distance measures in cosmology" David W. Hogg though a more complete article is. http://arxiv.org/abs/astro-ph/0310808:"Expanding Confusion: common misconceptions of cosmological horizons and the superluminal expansion of the Universe" Lineweaver and Davies

To improve upon its confidence level and accuracy. Relativity is a big pill for many to swallow. However if you think about it we test one aspect of relativity in particle accelerators 100's of times every day. That being inertial mass and the amount of energy required to accelerate the protons. We even have an atomic clock on Mount Everest testing time dilation. Then you also have muon decay. Normally muons couldn't reach the Earths surface. But they do thanks to good ole time dilation. Comments on the tests of relativity. http://arxiv.org/pdf/0806.0528 http://www.astro.sunysb.edu/rosalba/astro2030/GeneralRelativity_tests.pdf

You send a signal with a response request then devide the time for the signal to get back to you by two. This way you can calibrate signal delay including electronic process delays. A more accurate method though could be sending a request to the RTC (real time clock) on the satellite requesting the time of receiving a signal. Then compare to two precalibrated atomic clocks. One on Earth one on satellite. From that data one can calculate the distance to a satellite. Granted we don't rely on one method. If you combine the previous data with parallax you can fine tune the distance/rate of signal. After all a signal moving through a medium can cause delays so you will need to study and test that medium. (Ie atmosphere). After years of transmission though we have an extremely high degree of accuracy in knowing the properties of the atmosphere and local spacetime medium. (Though we still continually test it for changes). That's one aspect ppl fail to recognize in science. We continously test. Particularly on something as critical on distance measures, redshift, luminosity/distance relation and relativity. This continous testing leads to extreme fine tuning. As such numerous tests are continuously developed to help strengthen our accuracy.

David knowing how to calculate the proper distance of any object is far more useful than calculating the volume. In the case of expansion you only need to calculate the radius. From there it's simply one calculation to determine the volume. Simplistic isn't the true reason however. In order to find the distance of a measured object, one has to factor in the redshift. Or luminosity to distance relationship. Granted the method will vary depending on what distance your looking at. Google "cosmic distance ladder" As your already working at measuring distance ie you wish to confirm how far an object has moved due to expansion... it doesn't make sense to worry about volume change until you need to do so. When you think about it knowing the proper distance to an object ie Cosmological event horizon, distance galaxy etc is far more practical than knowing the enclosed volume. This practicality is naturally already in place. When you wish to measure the observable universe you must first measure the distance to the observable universe cosmological event horizon. Before you can calculate the volume of the observable universe you must first know the radius. In that measurement you will need the redshift. From there you determine the scale factor. then you use the proper distance formula on that wiki link Strange provided. From that data you calculate the volume if you so desire. for wavelength change Google Weins displacement law. https://en.m.wikipedia.org/wiki/Wien's_displacement_law http://astronomyonline.org/Science/WiensLaw.asp

Roughly 43 million light years in radius.

There is outside our observable universe. Not necessarily outside the universe itself. I gave an example on this thread showing the related math of an adiabatic expansion with no heat transfer.

Yes it is. welcome to Cosmology applications that naturally include physics, thermodynamics and particle physics. Of course you also need relativity and differential geometry with statistical mathematics. What's your expertise? (Granted QM is needed I'm cosmology to understand the principle of least action in say the SO(1.3) Lorentz group in gauge symmetry. Which is also used to deal with how particles move.) Trust me resident experts and above can easily see to persons with low physics knowledge. If you knew basic physics. You would not have needed to Google the term "work". PS that term is taught in high school physics (in Canada grade 3) Here is The crux. Direction on improving your ideas have been provided. Learn.... Several experts have read your OP. We all find it lacking and full of errors. Rather than nit pick them. We chose to provide teaching. choice is yours. In order to understand the involved math you will need to understand why that math works. Or why it was developed to be so hard fast and tried. As of yet you've not shown one shred of evidence that thousands of professional scientists are wrong.

pS. Explain Particles that do not interact via the electromagnetic but do in gravitational. (Neutrinos). How do they correlate into gravito-magnitism.

The one mention section you posted David on the behaviour of a higher energy-density/pressure/temperature is accurate. Any higher state in the aforementioned three will naturally develop into a lower value. Key note 'based upon heat or work transfer to amnther outside thermodynamic state Here is the problem of development of this principle into a "cosmological constant". Lets take your example first. Strict higher temperatures moving to a zero temperature state. (If you study thermodynamics this leads to a preference direction. {Hot to cold}= Measurements show no sign of the above action. (CMB temperature) Now the question comes into play.... can our uniform measurement of the CMB agree with this action. My knowledge (after 30 years study days no). If you noted the conversation between Carrock and others during this thread. The subject came up. Thus far this thread no evidence or supported papers have shown up on anything other than a homogeneous and isotropic fluid in Cosmology terms been presented). Any suppositions presented have lacked following supported material.