The expansion of spacetime is NOT accelerating.
The Mainstream description of the expansion of the Universe is that it is accelerating. This description is erroneous and it is also an improper evaluation of what is observed.

The super “standard candle” – 1a supernovas
When a star explodes as a supernova, over a few days it produces as much light as a 100 billion stars. Type 1a supernovas are a unique type of supernova in that they explode with a very specific amount of mass. The great physicist Chandrasekhar determined that the critical mass for these supernovas is about 1.4 solar masses. Since type 1a supernovas have a fixed amount of mass associated with their destruction, they can serve as “standard candles” to determine distance and since these supernovas are so bright, they can be used to determine extreme distances, more than a billion light years away.

Space is “accelerating”
When it was discovered that type 1a supernovas at a red shift of about .5 or so were dimmer than expected from the assumed rate of expansion, it was concluded by most that they had to be further away, and it was declared that the universe was “accelerating”. Link to supernova group work, here. http://www-supernova.lbl.gov/public/...ysicsToday.pdf

The “unconventional” graph
The graph of the supernova group is in the form the data was taken, magnitude verses red shift. This is an unconventional plot and in order to understand what is really happening has to be translated in to a more familiar form.

Conventional graph of motion
Typically, when a high school physics student is asked to draw a graph describing the motion of an object, the distance traveled is plotted over time. The slope corresponds to the velocity. If the slope is constant, the object is moving at a constant velocity. If the slope is negative (sloping down hill) the object is moving towards the observer and if the slope is positive (sloping up hill), the object is moving away. If the slope has a negative curvature ( a frown shape), the object is decelerating. If the slope is positive, (a “smile” shape) the object is accelerating. Basic physics 101.

Motion is model dependant
It is also important to note that the description of an object accelerating or decelerating is model dependant. The simplest model predicting the rate of expansion of the universe is the Friedman – Einstein model. It assumes the expansion of the universe is Flat, ie poised between expansion and collapse. The expansion would also be the fastest when the universe began, and due to gravitational interaction, the expansion of the universe would slow or decelerate. The expansion of the universe will slow to a stop after an infinite amount of time has passed. A deviation from this predicted rate would be described as a “discovered” acceleration or deceleration.

Conventional graph of expected rate of expansion
The following link leads to a graph I made that describes the expansion of spacetime as expected from the simplest application of general relativity.
http://d77591.u25.existhost.com/gpage15.html (Hope this link works now, "fixed" next day)

Conventional graph of observed data
The following link leads to a graphical representation of the expansion of space, based upon the graphical data provided by the type 1a supernova group’s graph above. The magnitude and red shift values have been translated to a conventional graphical representation of distance verses time. It assumes that 1a supernovas are true constant standard candles.
http://d77591.u25.existhost.com/gpage16.html

Analysis of Graph
A careful review of the second graph is in order. The slope of the graph is always positive, indicating that the galaxies are always moving away from each other. The curvature indicates both acceleration and deceleration. Now lets look at the rates of acceleration over time. Initially the galaxies start off with a high velocity and due to gravitational interaction, the rate of expansion between galaxies slows. This is indicated by the negative curvature (frown shape). Then at about a red shift of .5, (about 3/4 along the x axis), the assumed apparent distance between galaxies is greater, which produces a positive curvature (smile shape). This correlates to an acceleration of spacetime. There is a point of inflection somewhere between the deceleration and acceleration. As we look at the relationship closer to our present era, the rate of expansion is constant, hence the term “Hubble’s Constant”. In order for the indicated positive curvature observed at a red shift of .5 to transition to a 0 curvature (a flat line) there appears to be a negative curvature to form a transition. (Although it may also be an acceleration that is diminishing to 0 without a negative curvature). Technically and exactly, based upon the data in the graph, the universe appears to be first decelerating, then it was accelerating, and then in order to conform to the constant rate of expansion we observe now, the rate of acceleration has diminished so much that the current rate of expansion is constant. .

(It may be argued that the acceleration rate observed at the .5 red shift is just slowing down to a constant rate, and it is still in effect, just at a very imperceptible rate. This is tantamount to admitting the acceleration is imperceptible, and if it is imperceptible it cannot be said the universe is presently accelerating with any degree of confidence. It also does not reflect observation, local galaxies are blue shifted, which could be from gravitational interaction but even if it is gravity causing the blue shift observed with the local galaxies, the physical description of what is observed is consistent with a constant rate of expansion, leaning slightly towards deceleration.)

The second graph corresponds to our observation. Locally, the distance between galaxies varies linearly and as we observe the galaxies further away, they appear to be further away (D is greater).

Is the universe “accelerating”? The graph indicates this acceleration is no longer in effect. The expansion is now very close to being constant.

This is not meant to diminish the significance of the discovery of the dimmer than expected type 1a supernovas. It is a remarkable discovery. The description is misleading, one may be led to the idea that the universe is presently accelerating, when in fact the expansion rate is presently extremely close to being constant, ie “Hubble’s constant” is constant. A careful look at the relationship shows that if there were any “leaning” of the current description of spacetime from a constant rate, it would have to be that of deceleration.

It’s the supernovas that are changing, and not the Rate of expansion.
There is another more significant point to be made and that is regarding the assumption that type 1a supernovas are the same in the past as they are now. If there were some way to explain why younger (more distant) type 1a supernovas are not as bright, it should be seriously considered, especially if they restore the expected simple rate of expansion predicted by General Relativity. Remember, accelerating space results in requiring some new unknown energy source, “dark energy”.

Gravity as a function of Cosmic Time
If the effect of gravity were greater in the past than it is now, then it would not take as much mass to reach the critical pressure for a type 1a supernova to explode. If it takes less mass, then the amount of light emitted would be less, and thus it would appear dimmer. This is what is really happening.

I’ll post some of the figures backing up this statement in less than a week.

So not only is the description of the “accelerating” universe misleading, the justification of “dark energy “ is false.

John M. Kulick
AKA - Snowflake.

P.S. Thank you Tobin Dax. I finally made the graphs. Took awhile since by graphics generator failed.

Shouldn't that just be "space" instead of spacetime? What do you mean, spacetime is accelerating? Isn't accelertation time dependent, in this sense?
Isn't the main justification the rotation curves of the galaxies?

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8) Honestly, Snowflake.... think about this..

Space isnt expanding... BUT... It is trying to... and so looks like it is.

The 4th dimension.... the idea.. a hypercube.. you know.
Balloon expansion...
Moving up and to the side at the same time.. without going diagonal.

4D motion... now, assuming we have a 3D space.. a sphere.
How could we theoretically make it move 4 dimensionally????

By spinning it in 2 directions. giving it 2 spins, on 2 axis, at 90 degrees apart. this yeilds a force at 90 degrees to all the 3 dimensions.
assuming space, as a transindental fluid can move 4 dimensionally, or should i say, is willing to, under the force of applied energy.

do you see it... 4D motion... yields 4 dimensional spatial displacement, and if... and mind you i realise... if.. if... space resists, expansion, if that is the case, that means, that it is possible that the resistance to that expansion would take the form of what????????????????????????

theoretically, Spatial Tension... from the center outward, a tension, formed in direct response to the undersired or impossible motion of expansion.

the spatial tension... is then the fundamental particle.

and as ive pointed out, following this line.. energizes the particles, into mass.

and it could lead to hydrogen and helium, but i dont think so.. yet i a biased.

-MT
What we have now... today.. is the left over motion of space, which we commonly refer to as time flow.
perhaps we can refer to it as The Relative Velocity Dependant Rate of 4D Two Directional Spatial Motion.

That's dark matter.

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My mistake. I'll read more carefully next time, I hope.

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My link to the website hosting the graphs is not working. Computers drive me crazy. I am so sorry, I am trying to get it fixed.

John

Seems to work now. Post is worthless without the graphs.

Thank you for your interest and I will be responding to the replys soon. My son is graduating from High School and I have to zoom.

Respectfully yours
John

Some quick comments:

- you have no datapoints, nor error bars, on your graphs, snowflakeuniverse. This makes it impossible to do anything with your idea. Further, there's now more data than the points you reference, and (almost?) all folk who work in this field do at least some statistical analyses on the data - will you be doing this in future too?

- the distant SNe work is much more extensive than simply light curves. For example, considerable effort has gone into addressing the question of similarity (are distant Type 1a SNe truly like local ones?), e.g. the appearance of absorption features in the spectra, over time. Second example, time dilation. The distant SNe have light curves that are 'stretched' by just the right amount (within the limits of the data) to be at the distances implied by the lambdaCDM model (plus 'DE'). Have you done the analyses, within your idea, to show that these other aspects of the SNe observations are consistent?

- cosmological models which incorporate DE fit a range of good observational data better than those which don't ... even without the distant SNe data! The point is that the SNe data further constrains the models (the volume in parameter space which is consistent with all data is much smaller), and that there are no data which don't fit!

I look forward to your paper, outlining how your idea is fully consistent with the same set of good observational results that the concordance model is (or, better, that the fit to the data, using your idea, is actually tighter).

As always intresting theroy snowflake.

To be honest I never bought into the 'Standard Candle' theroy myself. It can give us an 'Estimate' of distances, but it's never presented as that, but more as a fact.

My issues with it Are:

For the Type 1a Supernova's to have 'exactly' the same luminosity is an imposibility. White dwarph's are mostly carbon yes, but they will also contain the same proportion of heavier element's as the origional star. Any difference in composition of over .01% would be reflected both in the luminosity of the final nova, and in it's spectography. A white dwarph of pure carbon, accreting put hydrongen from a companion, would have a luminousity much less then one with .02% oxygen and .01% iron in it.

Even if they had the same mass, but with different components, the energy released in a mixed core is larger. The part oxy/iron in my examply would generate more energy and faster when some of the oxygen and iron undo catastophic fusion. This would cause the reaction in the rest of the material to also be accelerated of a pure carbon form.

It could posibly yeild a nova around 1 magnitude difference in luminosity, that would also burn out at a faster rate.

Additionaly the type of matter being accreted onto it that leads to the nova can be just as variable as the composition of the star.

I do realize that they hit a point in critical mass, and that will always be the same, but even just looking at the timing and length of a few type 1a's and thier variences, I just don't see how it could be an accurate representation of distance. A good estimate? Yes, but far from accurate.

In this case I'm more sceptical then the scientist that use this method probably. I'd need to see to see some hard evidence that these type of nova's occur at exactly the same luminosity and rates, with spectral signatures, to put more credence into the distances and luminoisty/red shift they use them to estimate.

I'm not totaly knocking the method either, it's an ingenous idea. But I haven't heard of any study being done on the variability of these nova's due to compositions.

My doubts stem from what happened during the V838 Mon Outbust. When it was first detected, the star was considered just sligtly more massive then Sol at 1.2 solar masses. (et. al. APOD, NASA, hubblesite). For about two years this stayed the same.

Then it became a 4 solar mass star for a while, then a 5-10 mass star...then the supositions about it going red giant in six months was due to swallowing a lage gas giant, or accretion form a companion...

Yet before all this it was rated as a 1.2 solar mass, had a spectral curve that was consitant with that mass of a star, etc...

It's been the contention of a rare few that it's fast evolution into a red giant was due to core composition and not higher mass. We know that stars that have heavier elements can be smaller, have a more stable and longer lasting main sequence, and less variable nature. But the same heavier elements that stabilize fusion during main sequence, would also effect it's evolution, possibly in atypically more rapid manners.

This work made sense to me, and as all information on the star before the even was of a 1.2 sol mass variable, (and there is/was a lot of information this way), this sort of indicated that 1. we know a heck of a lot less about stars then we thought. 2. They evolve in a mouch more varied manner, dependen't on more mass and compostion.

I had to ask myself: if a star that is around 1.2 sol masses can so radically evolve, what would the same compositions cause in other events. Thats when I did a little hunting and found out that type 1a's did not always display quite the same time frames for thier out busrts. Some were a bit shorter and some longer.

So now I sort of question the accuracy of the method. It would seem more honest science if the small variablility in the nature of these were accounted for and we had distance estimates in a low range/high range type presentation.

I could just be nick picking though lol.

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Actually, if you read the literature (and since you are making such sweeping statements about all this, I assume you have read the literature) you will find that there are copious papers trying to figure out if Type Ias from the past are different somehow, or if there is some other reason for the spectra to be different. An exhaustive search has turned up nothing.

While there is still a good deal we don't know about these supernovae, so from theory we can't say how certain we are that they are standard candles, the observational data is pretty good ... when various, well-known factors are taken into account, these objects have a small range of intrinsic magnitudes.

In any case, there are always uncertainties in astronomical measurements; but there is also - in astronomy - the opportunity to find plenty more examples of a particular type of object or event, and then it's statistics to the rescue!

Indeed, if you look at the figure in the link snowflake gives, you'll see how stats are used to estimate the cosmological parameters ... from somewhat noisy data.

Well as I said I'm probably just nick picking.

Law of averages being what it is, the varience of durations of these SNe will average themselfs out in the long run. I still think it could be slightly more accurate if durations were accounted for as well as luminosity, for each event. But I don't have the access to this kind of data to even begin that sort of a study.

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A layman's question about all of this: is there a correlation between the red shift of a SN1a and the luminosity?

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If you mean the observed magnitude, then yes. SN1a are standard candles ... it's through the derived absolute magnitude (worked out from the observed magnitude, the light curve, and so on) that the distance is estimated.

Hi Neried

You mentioned that
“you have no datapoints, nor error bars, on your graphs”

You are correct, in fact the curves for the second graph are exaggerated. The second graph does show that if the data of the supernova relationship were plotted in conventional distance verses time relationships, there is no current “acceleration”.

(If you want to transform the supernova’s graph to that of a standard distance verses time relationship, the proper measure and direction of time on the x axis needs to be established with the beginning of time marking the 0 point on the time axis and the “present” represented at the end of the plot To fix or transform the supernova’s graph to more closely conform to standard distance and time relationship, rotate the supernova groups graph 90 degrees, swapping the x and y axis, then rotate the graph around the new vertical axis 180 degrees.)

Hubble’s constant is constant, at least to a look back time associated with a red shift factor of .1. It is only in the past that there is any evidence of “acceleration”. Therefore the universe is not currently accelerating.

I will be addressing the issue of the similarity of high red shift 1asn’s with local ones in a response to “Bad Astronomer”.

Thank you for your response and interest. I appreciate the feedback.

John

Hi Dgvin

You bring out some good points concerning our seemly blind acceptance of the standard candle assumed for 1asn’s. They are trying to account for variations in the spectral characteristics but trying to account for the variation due to the white dwarf and the donor star will certainly confuse the issue.

When Cepheid Variable stars were first used as a standard candle, the magnitudes for distant Cepheid Variable stars were off by a factor of four. The effects of the accumulated heaver elements within the cores of the stars over time were not properly accounted for. This time we are only looking for a variation in the energy output of 1asn’s of about 25 percent, who knows what unaccounted effect is presently being ignored.

It is the unabashed certainty that the “mainstream” has in just one interpretation of the data that seems so unjustified, particularly since the data is not conforming to our expected understanding of the laws of physics. Adding “dark energy” as a fix has to be understood as at least questionable.

John

Hi Bad Astronomer

You stated

"that there are copious papers trying to figure out if Type Ias from the past are different somehow, or if there is some other reason for the spectra to be different. An exhaustive search has turned up nothing."

Not true.

A few years ago (1999 I think) Riess, Filippenko, Schmidt and Weidong Li, found that distant 1asn have a time to maximum luminosity close to 17 days – 2.5 days less than the rise times of local supernovae. This discovery was based upon a few data points. My theory predicts this kind of shorting of the light curve.

Since that time more data points have been established, and depending upon whom you talk to the above discrepancy has either disappeared or still remains. The variation in the data is enough to allow either interpretation. (I was also told this was so by one of the “experts” at the last American Physical Society meeting this April. Once I find my notes I can give you his name.)

John

Jerry has also made some interesting arguments about this.

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