Topic: dark matter theory being replaced?
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mightymoe

Sat 09/16/17 09:27 AM

The accelerating expansion of the Universe may not be real, but could just be an apparent effect, according to new research published in the journal Monthly Notices of the Royal Astronomical Society. The new study—by a group at the University of Canterbury in Christchurch, New Zealand—finds the fit of Type Ia supernovae to a model universe with no dark energy to be very slightly better than the fit to the standard dark energy model.

Dark energy is usually assumed to form roughly 70% of the present material content of the Universe. However, this mysterious quantity is essentially a place-holder for unknown physics.

Current models of the Universe require this dark energy term to explain the observed acceleration in the rate at which the Universe is expanding. Scientists base this conclusion on measurements of the distances to supernova explosions in distant galaxies, which appear to be farther away than they should be if the Universe’s expansion were not accelerating.

A computer-simulated image depicting one possible scenario of how light sources are distributed in the cosmic web.

Credit: Andrew Pontzen and Fabio Governato / Wikimedia Commons (CC BY 2.0).

However, just how statistically significant this signature of cosmic acceleration is has been hotly debated in the past year. The previous debate pitted the standard Lambda Cold Dark Matter (ΛCDM) cosmology against an empty universe whose expansion neither accelerates nor decelerates. Both of these models though assume a simplified 100 year old cosmic expansion law—Friedmann’s equation.

Friedmann’s equation assumes an expansion identical to that of a featureless soup, with no complicating structure. However, the present Universe actually contains a complex cosmic web of galaxy clusters in sheets and filaments that surround and thread vast empty voids.

Prof David Wiltshire, who led the study from the University of Canterbury in Christchurch, said, ”The past debate missed an essential point; if dark energy does not exist then a likely alternative is that the average expansion law does not follow Friedmann’s equation.”

The difference in the magnitudes of supernovae in the ΛCDM and Timescape cosmologies and the magnitudes the supernovae would appear to have in an empty universe (horizontal dashed line). Both models show recent apparent acceleration following earlier deceleration. In the Timescape model this is not a real effect, however, and the curve is flatter than the ΛCDM case.
Credit: Lawrence Dam, Asta Heinesen and David Wiltshire.

Rather than comparing the standard ΛCDM cosmological model with an empty universe, the new study compares the fit of supernova data in ΛCDM to a different model, called the ’timescape cosmology’. This has no dark energy. Instead, clocks carried by observers in galaxies differ from the clock that best describes average expansion once the lumpiness of structure in the Universe becomes significant. Whether or not one infers accelerating expansion then depends crucially on the clock used.

The timescape cosmology was found to give a slightly better fit to the largest supernova data catalogue than the ΛCDM cosmology. Unfortunately the statistical evidence is not yet strong enough to rule definitively in favour of one model or the other, but future missions such as the European Space Agency’s Euclid satellite will have the power to distinguish between the standard cosmology and other models, and help scientists to decide whether dark energy is real or not.

Deciding that not only requires more data, but also better understanding properties of supernovae which currently limit the precision with which they can be used to measure distances. On that score, the new study shows significant unexpected effects which are missed if only one expansion law is applied. Consequently, even as a toy model the timescape cosmology provides a powerful tool to test our current understanding, and casts new light on our most profound cosmic questions.

Contacts and sources:
Dr Alyssa Drake
Royal Astronomical Society

Prof David Wiltshire
University of Canterbury
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Tom4Uhere

Sat 09/16/17 12:08 PM

I've always understood that "Dark" energy/matter was only a placeholder for unexplained cosmology physics.
Evidence of cosmological physics can be seen in atoms. Atoms are also the Universe.

Relativity is a major factor in observing expansion. Not only is there a size relativity there is a time relativity.

Many people I have talked with understand the Big Bang concept as an explosion. When someone thinks of an explosion they usually think a violent expansion from point A to surrounding points a distance away from point A. Material moves directionally.

I see the Big Bang as an eruption at all points at the same time. Like a percolation of matter forming at fractures of vacuum energy.
Matter, having mass and in turn gravity, sets everything to motion.
Over time, the matter creates greater gravity causing larger and larger scales of movement. The movement in space is created by gravity of mass, not the result of a big explosion.

Filaments are areas where the vacuum energy erupted into matter. With higher matter content, filaments condense into larger and stronger areas of gravity influence over the areas that did not have a strong vacuum energy eruption. These voids are caused by gravity of the filaments.

In this way I see space as percolating, pulsing unevenly. Our relative size and duration of observation is skewing the apparent results.

If you think about it, all celestial movement stems from gravity which is a product of mass. Sometime in the far future the Universe will consist of nothing but black hole singularities and those black holes will be moving around on the affects of mass's gravity. This will be long after the entire Milky Way galaxy has been collected to its black hole. I imagine a time when the majority of space will be the voids and the dying black holes will be filaments of matter/gravity like shattered glass (glass cube not pane).

finds the fit of Type Ia supernovae to a model universe with no dark energy to be very slightly better than the fit to the standard dark energy model.

The problem with measuring speed from distant objects is that gravity is affecting the observation. It must assume that the observation platform is steady and constant. Gravity is not steady and constant. The name "Gravitational Wave" even denotes a pulsing wave-like motion. Gravitational waves actually do exist, been scientifically proven to exist.

Since matter has mass and that mass results in variable gravitational waves determined by the amount of mass of any given object, space is a sea of gravitational waves of varied intensity and direction. It skews the precision of measurements over vast distances.

The Sun isn't just revolving around the Milky Way center. It moves up and down and round and round the Orion Arm's gravitational filament while it slowly moves closer and closer to the center of the galaxy. I believe that the milky way is moving in a similar fashion in relation to a larger gravitational filament. All this movement is relatively undetectable by us.
But, speed up time and take a more distant look and it could be seen, just like if you multiply time settings in Celestia to make the planets spin faster.

The only way we could ever claim anything about the movement of the Universe is if we take measurements from a significantly distant observation point outside the galaxy in which we reside.
Then compare the measurements.

I could be right, I could be wrong but the effects of gravity/mass can be observed at our relative scales. Since we are within the Universe we are witnessing the Universe. We are witnessing it within the conditions that exist in this part of the Universe.
We see how an atom is constructed. We can't know if a carbon atom has the same construction or distance of electron orbits in black holes or cosmic voids because we can't measure them in that environment naturally. We can try to simulate those conditions in a lab but those simulations will be skewed because the lab exists inside our cosmological environment.

Its possible that in a cosmic void an atom's protons and neutrons have an parabolic orbit to them and the electron orbits are at a greater distance from the center. Or...In a black hole atoms electrons do not orbit, they are fused to the nucleus.
If higher mass/gravity compacts then lower mass/less gravity should expand.

All these differences over distance changes the accuracy of observational deductions. Throw in time relativity and accuracy is changed even more.
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Tom4Uhere

Sat 09/16/17 12:26 PM

Take a video of boiling water focused on a single bubble.
Your camera has a shutter speed of 13.7 billion frames per second.
Your video is 5 frames in duration.

The bubble doesn't appear to move at all. Using instruments, you measure and find that it had moved fractionally closer to you in every frame. You assume from this observation that boiling water bubbles grow. Transfer that assumption to the movement of the Universe and you might proclaim that the Universe is contracting because the bubble fractionally gets larger over time.

In 13.7 billion years we have had measuring instruments gathering data for lets say 50 years. We are measuring one bubble in a Universe of boiling water over an insignificant period of time. We claim, "this is how the Universe is" and expect it to hold merit.
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mightymoe

Sat 09/16/17 03:17 PM

thats only because they "assume" the universe is 13.7 billion years old... i think it's trillions upon trillions, just a big recycling center that reuses everything that gets destroyed...the latest theory is that all matter in the universe is a constant, then matter cannot be created or destroyed, just turned into something else,like energy... kinda throws a dampener on the big bang theory...
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Tom4Uhere

Sat 09/16/17 03:42 PM

I merely used 13.7 billion because that is the going guess.
I too believe it is inaccurate and the Big Bang/Big Crunch theories hold no value.

If you are interested look into Vacuum Energy and Planck Constant.
Specifically the spontaneous generation of matter and antimatter from energy. Merely another theory but any theory can be as valid or invalid as any other theory because they are theories. Sometimes called Zero-Point Energy.

You may also find these two videos on The Cosmological Constant interesting. They are quite long and are lecture type videos.

Cosmic Microwave Background Spectrum and the Cosmological Constant, Part I ~ from MIT OpenCourseWare
http://www.youtube.com/watch?v=MKPswx4hjec
The Cosmological Constant, Part II
http://www.youtube.com/watch?v=U_Ot1PTuUv4&t=15s

I also recall a simplified version of the Cosmological Constant as a segment of an episode of the TV show The Universe but I don't recall the episode or have a link to a video of it.

Remember that not all scientists give credence to all theories. Depending on who is writing or who you ask even string theory is subjective to acceptance. The same was said about quantum theory until it became quantum mechanics.

Having no career or reputation on the line I am free to consider all theories and make my own assessments.

I once asked what makes a theory more than imagination and was told the validity of the one making the theory. So basically, since I believe everyone has their own imagination anyone's theory is valid until proven.
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mightymoe

Sat 09/16/17 03:44 PM


I merely used 13.7 billion because that is the going guess.
I too believe it is inaccurate and the Big Bang/Big Crunch theories hold no value.

If you are interested look into Vacuum Energy and Planck Constant.
Specifically the spontaneous generation of matter and antimatter from energy. Merely another theory but any theory can be as valid or invalid as any other theory because they are theories. Sometimes called Zero-Point Energy.

You may also find these two videos on The Cosmological Constant interesting. They are quite long and are lecture type videos.

Cosmic Microwave Background Spectrum and the Cosmological Constant, Part I ~ from MIT OpenCourseWare
http://www.youtube.com/watch?v=MKPswx4hjec
The Cosmological Constant, Part II
http://www.youtube.com/watch?v=U_Ot1PTuUv4&t=15s

I also recall a simplified version of the Cosmological Constant as a segment of an episode of the TV show The Universe but I don't recall the episode or have a link to a video of it.

Remember that not all scientists give credence to all theories. Depending on who is writing or who you ask even string theory is subjective to acceptance. The same was said about quantum theory until it became quantum mechanics.

Having no career or reputation on the line I am free to consider all theories and make my own assessments.

I once asked what makes a theory more than imagination and was told the validity of the one making the theory. So basically, since I believe everyone has their own imagination anyone's theory is valid until proven.
drinker :thumbsup:
no photo

...

Wed 10/11/17 09:25 AM

My own opinion favours sine waves. Currently the universe is expanding. At some point it will reach a maximum size and then start to shrink until everything collapses into a Big Crunch, which will be the next Big Bang. Thus matter remains constant, always has been and always will be. Thus time is also infinite, always has been and always will be. Avoids having to answer the question, "What existed before time started?"

As a side effect, all matter that we currently would describe as 'positive' will become 'negative', i.e. anti-matter. And vice-versa of course.
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Integrityis1st

Wed 10/11/17 10:03 AM


I've always understood that "Dark" energy/matter was only a placeholder for unexplained cosmology physics.
Evidence of cosmological physics can be seen in atoms. Atoms are also the Universe.

Relativity is a major factor in observing expansion. Not only is there a size relativity there is a time relativity.

Many people I have talked with understand the Big Bang concept as an explosion. When someone thinks of an explosion they usually think a violent expansion from point A to surrounding points a distance away from point A. Material moves directionally.

I see the Big Bang as an eruption at all points at the same time. Like a percolation of matter forming at fractures of vacuum energy.
Matter, having mass and in turn gravity, sets everything to motion.
Over time, the matter creates greater gravity causing larger and larger scales of movement. The movement in space is created by gravity of mass, not the result of a big explosion.

Filaments are areas where the vacuum energy erupted into matter. With higher matter content, filaments condense into larger and stronger areas of gravity influence over the areas that did not have a strong vacuum energy eruption. These voids are caused by gravity of the filaments.

In this way I see space as percolating, pulsing unevenly. Our relative size and duration of observation is skewing the apparent results.

If you think about it, all celestial movement stems from gravity which is a product of mass. Sometime in the far future the Universe will consist of nothing but black hole singularities and those black holes will be moving around on the affects of mass's gravity. This will be long after the entire Milky Way galaxy has been collected to its black hole. I imagine a time when the majority of space will be the voids and the dying black holes will be filaments of matter/gravity like shattered glass (glass cube not pane).

finds the fit of Type Ia supernovae to a model universe with no dark energy to be very slightly better than the fit to the standard dark energy model.

The problem with measuring speed from distant objects is that gravity is affecting the observation. It must assume that the observation platform is steady and constant. Gravity is not steady and constant. The name "Gravitational Wave" even denotes a pulsing wave-like motion. Gravitational waves actually do exist, been scientifically proven to exist.

Since matter has mass and that mass results in variable gravitational waves determined by the amount of mass of any given object, space is a sea of gravitational waves of varied intensity and direction. It skews the precision of measurements over vast distances.

The Sun isn't just revolving around the Milky Way center. It moves up and down and round and round the Orion Arm's gravitational filament while it slowly moves closer and closer to the center of the galaxy. I believe that the milky way is moving in a similar fashion in relation to a larger gravitational filament. All this movement is relatively undetectable by us.
But, speed up time and take a more distant look and it could be seen, just like if you multiply time settings in Celestia to make the planets spin faster.

The only way we could ever claim anything about the movement of the Universe is if we take measurements from a significantly distant observation point outside the galaxy in which we reside.
Then compare the measurements.

I could be right, I could be wrong but the effects of gravity/mass can be observed at our relative scales. Since we are within the Universe we are witnessing the Universe. We are witnessing it within the conditions that exist in this part of the Universe.
We see how an atom is constructed. We can't know if a carbon atom has the same construction or distance of electron orbits in black holes or cosmic voids because we can't measure them in that environment naturally. We can try to simulate those conditions in a lab but those simulations will be skewed because the lab exists inside our cosmological environment.

Its possible that in a cosmic void an atom's protons and neutrons have an parabolic orbit to them and the electron orbits are at a greater distance from the center. Or...In a black hole atoms electrons do not orbit, they are fused to the nucleus.
If higher mass/gravity compacts then lower mass/less gravity should expand.

All these differences over distance changes the accuracy of observational deductions. Throw in time relativity and accuracy is changed even more.

WOW!
The only way we could ever claim anything about the movement of the universe is if we take measurements from a significantly distant observation point outside the galaxy in which we reside. :thumbsup: Lots a pulsating suck going on.
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greeneyes148

Fri 10/13/17 06:56 AM

dark matter theory being replaced?

_____________________________________________________________________

Hmmm.. now that you mention it, I haven't seen Bobby Brown on T.V.
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no1phD

Fri 10/13/17 09:28 AM

X I'm just a moron myself..
But I always thought of the expansion of the universe or the Big Bang as being similar to taking a drag from a cigarette feeling you're lungs up.. and then exhaling all the smoke into a very large empty room.. from the starting point your mouth. The smoke is dense and thick but over time it spreads out throughout the whole room.. feeling the room completely.. overtime.. Dark Matter would just be what the room was filled with before the smoke was there... dark matter is unmeasurable.. I think.. but it must be able to move in order to accommodate room for the smoke.. in this example.. and after some time the entire room is filled with a light mist of smoke it would be rather hard to tell where the smoke originated from at what point in the room..
Did the smoke leave your mouth.. it gets dispersed evenly throughout the room...
Probably not the best example...
But my question would be.. they say the universe is endless.. in my example if you have a big enough room the amount of smoke or mass or energy that the smoke represents in this scenario.. the original Big Bang.. there's a point that there's not enough mass or energy to reach the other side of the room.. if the room was big enough.. now I myself have blown smoke into a rather large gymnasium when I was young.. just only the amount I could hold in my lungs.. and on the far far end in the gymnasium there was a little window..
After a few minutes you could just see a wisp of the smoke cutting through the Sunbeam coming in through the window...
It always amazed me how that one lung full of cigarette smoke could fill up that entire room....hmmm.... yes I get it now smoke particles are very tiny


Edited by no1phD on Fri 10/13/17 09:32 AM
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mightymoe

Fri 10/13/17 10:14 AM


X I'm just a moron myself..
But I always thought of the expansion of the universe or the Big Bang as being similar to taking a drag from a cigarette feeling you're lungs up.. and then exhaling all the smoke into a very large empty room.. from the starting point your mouth. The smoke is dense and thick but over time it spreads out throughout the whole room.. feeling the room completely.. overtime.. Dark Matter would just be what the room was filled with before the smoke was there... dark matter is unmeasurable.. I think.. but it must be able to move in order to accommodate room for the smoke.. in this example.. and after some time the entire room is filled with a light mist of smoke it would be rather hard to tell where the smoke originated from at what point in the room..
Did the smoke leave your mouth.. it gets dispersed evenly throughout the room...
Probably not the best example...
But my question would be.. they say the universe is endless.. in my example if you have a big enough room the amount of smoke or mass or energy that the smoke represents in this scenario.. the original Big Bang.. there's a point that there's not enough mass or energy to reach the other side of the room.. if the room was big enough.. now I myself have blown smoke into a rather large gymnasium when I was young.. just only the amount I could hold in my lungs.. and on the far far end in the gymnasium there was a little window..
After a few minutes you could just see a wisp of the smoke cutting through the Sunbeam coming in through the window...
It always amazed me how that one lung full of cigarette smoke could fill up that entire room....hmmm.... yes I get it now smoke particles are very tiny



is the universe expanding, or does it look like it from our point of view? We can only see so far in the distance, so from our perspective it looks like the universe is expanding, but maybe it's just it's natural movement of billions of galaxies...