Cosmology and its problems

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Cosmology and its problems

Postby hyksos on August 17th, 2017, 9:57 pm 

The purpose of this thread is to elicit discussion about the modern state of cosmology , as a whole discipline. Some of these "problems" are well-known others less known. I will forgo including links to cited publications, as there are too many topics in the list to get around to. I'm happy to get into any particular topic in more detail with anyone. I appreciate any feedback or corrections.

This thread is made to seem combative on purpose. The discipline of cosmology is overly rife with excuse-making and pre-owned car salesmanry. After so many just-so stories, one gets the lingering impression that they are talking to a pathological liar.

1. Horizon problem.
There was not enough time since the Big Bang for thermodynamic energy to get from one side of the universe to the other -- and yet both sides are in perfect equilibrium. Canonical response: "The universe equilibriated in the first few nanoseconds before inflationary epoch took off."

2. The CMBR should be mathematically uniform.
But it's not. CMBR is anisotropic across the sky. How? Canonical excuse is that these imbalances are due to "quantum fluctuations" in the very early universe, or perhaps they are noisy echoes caused by some exotic inflationary theories. Take your pick from a wide array of hors d'oeuvres from our Excuse Table.

3. Galaxy Rotation curves don't follow gravity.
Canonical excuse: "dark matter". What is dark matter? "nobody knows".

4. Red-and-dead galaxies are older than the universe.
Excuse: "Something must be sucking the energy out of them." What is doing that? "Don't know."

5. Inflaton field shut off.
Today in the sky, there is no evidence of an "inflaton field" which is hypothesized to have driven rapid inflation. It turned off somewhere never to be seen again. Why? "Nobody knows, just play along."

6. The Milky Way should have stopped producing stars several billion years ago.
The Milky Way continues to produce fresh new stars, even when it should have run out of raw material about 3 billion years ago. Where is this raw material of the present day coming from? canonical excuse: "There must be gas entering the Milky Way from outside." Have we seen such an influx of gas? "Well no. It's hard to measure."

7. Galactic recycling.
Einstein was so confident in Steady-State that he just threw in a cosmological constant to counteract the inevitable collapse of stars into the center of the milky way. Surely Einstein was aware that a star could not simply shine for eternity. All stars must die. So we might ask : could a galaxy continue to reproduce stars forever? That process would be called "Galactic recycling." Turns out science can't answer the question because nobody knows how Galactic recycling works, exactly.

8 Population III stars

Population III stars are clean-burning super-bright stars that form from elemental hydrogen only. They existed in the early universe before any nucleosynthesis into heavy elements had yet manifest. Population III stars have never been observed by science.
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Re: Cosmology and its problems

Postby mitchellmckain on August 18th, 2017, 1:42 am 

hyksos » August 17th, 2017, 8:57 pm wrote:The purpose of this thread is to elicit discussion about the modern state of cosmology , as a whole discipline. Some of these "problems" are well-known others less known. I will forgo including links to cited publications, as there are too many topics in the list to get around to. I'm happy to get into any particular topic in more detail with anyone. I appreciate any feedback or corrections.

This thread is made to seem combative on purpose. The discipline of cosmology is overly rife with excuse-making and pre-owned car salesmanry. After so many just-so stories, one gets the lingering impression that they are talking to a pathological liar.

This is a bit overstated. I would say rather that a lot of it is rather soft (not backed up by hard evidence) and speculative.

But if you think any of this is a threat to science, think again. On the contrary, scientist are constantly searching for such discrepancies for in them is the promise of new discoveries.

hyksos » August 17th, 2017, 8:57 pm wrote:1. Horizon problem.
There was not enough time since the Big Bang for thermodynamic energy to get from one side of the universe to the other -- and yet both sides are in perfect equilibrium. Canonical response: "The universe equilibriated in the first few nanoseconds before inflationary epoch took off."

2. The CMBR should be mathematically uniform.
But it's not. CMBR is anisotropic across the sky. How? Canonical excuse is that these imbalances are due to "quantum fluctuations" in the very early universe, or perhaps they are noisy echoes caused by some exotic inflationary theories. Take your pick from a wide array of hors d'oeuvres from our Excuse Table.

5. Inflaton field shut off.
Today in the sky, there is no evidence of an "inflaton field" which is hypothesized to have driven rapid inflation. It turned off somewhere never to be seen again. Why? "Nobody knows, just play along."

I always did think inflation theory was more speculation than fact and always accepted the explanations with a grain of salt. There has been some evidence to support it, but on the whole I would consider this aspect of cosmological theory to be a work in progress.

hyksos » August 17th, 2017, 8:57 pm wrote:3. Galaxy Rotation curves don't follow gravity.
Canonical excuse: "dark matter". What is dark matter? "nobody knows".

Dark matter and dark energy are areas of physics where I remain even more skeptical.

hyksos » August 17th, 2017, 8:57 pm wrote:4. Red-and-dead galaxies are older than the universe.
Excuse: "Something must be sucking the energy out of them." What is doing that? "Don't know."

Unlikely. This is based on theories about galaxy formation and flaws in those theories are the most likely reason for the discrepancies.

hyksos » August 17th, 2017, 8:57 pm wrote:6. The Milky Way should have stopped producing stars several billion years ago.
The Milky Way continues to produce fresh new stars, even when it should have run out of raw material about 3 billion years ago. Where is this raw material of the present day coming from? canonical excuse: "There must be gas entering the Milky Way from outside." Have we seen such an influx of gas? "Well no. It's hard to measure."

Well the Milky Way certainly is not a static entity. All the spiral galaxies are very likely a result of gobbling up satellite galaxies and the evidence for this is quite abundant. We can, in fact, see all the different stages of this process from examples of satelite galaxies which are currently being devoured by the Milky Way. For example, there is a stream of matter and stars from the Magellanic clouds to the Milky way showing that these are in the process of being absorbed. I think this is also the reason why these satellite galaxies are so irregular in shape.

hyksos » August 17th, 2017, 8:57 pm wrote:7. Galactic recycling.
Einstein was so confident in Steady-State that he just threw in a cosmological constant to counteract the inevitable collapse of stars into the center of the milky way. Surely Einstein was aware that a star could not simply shine for eternity. All stars must die. So we might ask : could a galaxy continue to reproduce stars forever? That process would be called "Galactic recycling." Turns out science can't answer the question because nobody knows how Galactic recycling works, exactly.


Einstein said this was the biggest mistake of his life. The cosmological constant remains a possibility which scientists can fiddle with as a possible answer to other questions. But perhaps such solutions should be viewed with some skepticism.

hyksos » August 17th, 2017, 8:57 pm wrote:8 Population III stars
Population III stars are clean-burning super-bright stars that form from elemental hydrogen only. They existed in the early universe before any nucleosynthesis into heavy elements had yet manifest. Population III stars have never been observed by science.

This is like saying black holes have never been observed by science. It is stupid. There are perfectly understandable reasons why both population III stars and black holes would be difficult to observe. But, in both cases, we do have observational evidence of their existence. Despite the difficulties, such evidence has accumulated for black holes to such a degree that they have entered into the realm of scientific fact. The search for pop III stars has a different set of difficulties. Black hole candidates are at least fairly close by but pop III stars would have to be very far away or equivalently a long time ago.

What if none are ever found? What if they never existed? All it means is that the calculation for the abundance of other elements from the initial matter synthesis must be a bit off. Physicists would love it if this were the case because it would be a clue to new physics.
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Re: Cosmology and its problems

Postby bangstrom on August 18th, 2017, 1:04 pm 

Our observations of the universe appear to be telling us that the universe is much older and larger than predicted by the Big Bang theory.

This paper http://redshift.vif.com/JournalFiles/Pr ... 2N3ASS.PDF
suggests that the background temperature of 2.7K was identified prior to Penzias and Wilson and can (and was) explained as Eddington’s “temperature of the universe" due to heat generated by the many stars.

Gamov’s prediction for the amount of heat generated as a residual heat remaining from the primal fireball was considerably higher than 3K and intended to be in addition to the heat generated by stars so Gamov did not correctly predict the 2.7K as is often stated. Also, if the 2.7K temperature is entirely due to residual heat from the Big Bang, that implies that the temperature of the universe originating from the stars in deep intergalactic space is zero K. It seems unlikely that the intergalactic temperature of a universe filled with several billion galaxies should be zero.
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Re: Cosmology and its problems

Postby hyksos on August 18th, 2017, 4:59 pm 

Einstein said this was the biggest mistake of his life. The cosmological constant remains a possibility which scientists can fiddle with as a possible answer to other questions. But perhaps such solutions should be viewed with some skepticism.

A few factoids :
1. Einstein thought the "universe" was = "Milky Way galaxy".
2. Einstein had a sophisticated and modern understanding of energy.
3. Einstein felt an eternal universe was so "obvious" that he just threw in a constant into his equations.
4. Einstein must have known that a star, radiating so much light, could not shine forever.

Thus we ask : What process did Einstein think was refreshing stars in the "universe" (/milky way) ??

Leaving Albert alone for a second, how could anyone suppose that the universe is eternal in composition and density ("pretty much looks like it does now") , when we know that stars age and die?

How is any Steady-State theory viable in a universe where stars die?
Could Galactic Recycling reproduce stars ad-infinitum?
Are galaxies perpetual motion machines?

Your thoughts ...
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Re: Cosmology and its problems

Postby mitchellmckain on August 18th, 2017, 6:02 pm 

hyksos » August 18th, 2017, 3:59 pm wrote:
Einstein said this was the biggest mistake of his life. The cosmological constant remains a possibility which scientists can fiddle with as a possible answer to other questions. But perhaps such solutions should be viewed with some skepticism.

A few factoids :
1. Einstein thought the "universe" was = "Milky Way galaxy".
2. Einstein had a sophisticated and modern understanding of energy.
3. Einstein felt an eternal universe was so "obvious" that he just threw in a constant into his equations.
4. Einstein must have known that a star, radiating so much light, could not shine forever.

Thus we ask : What process did Einstein think was refreshing stars in the "universe" (/milky way) ??

Leaving Albert alone for a second, how could anyone suppose that the universe is eternal in composition and density ("pretty much looks like it does now") , when we know that stars age and die?

How is any Steady-State theory viable in a universe where stars die?
Could Galactic Recycling reproduce stars ad-infinitum?
Are galaxies perpetual motion machines?


I am not terribly interested in exploring what Einstein may have thought at some point in the past and how he might have reconciled things (far too speculative and susceptible to projection for my taste), but I certainly did enjoy looking into the history of our understanding of these objects like Andromeda.

Andromeda has been known at least since 964 AD, but like similar objects, it was until 1917 thought to be much smaller object in our own galaxy. At that point, comparisons between nova inside Andromeda compared with those in the Milky Way led to the conclusion that Andromeda was much farther away. Debate over the issue raged until Edwin Hubble settled it in 1925 with the identification of Cepheid variables stars in Andromeda which have long been used as a measuring stick for distance due to the well known relationship between their luminosity and pulsation period. (Yes this is from Wikipedia)

The idea that these could be closer objects in our own galaxy might seem strange until you take into account the many star clusters which are a part of our galaxy and which have a rather similar appearance.
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Re: Cosmology and its problems

Postby hyksos on August 18th, 2017, 6:07 pm 

mitchellmckain,

What relevance does this story have to Galactic Recycling?
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Re: Cosmology and its problems

Postby mitchellmckain on August 18th, 2017, 6:11 pm 

hyksos » August 18th, 2017, 5:07 pm wrote:mitchellmckain,

What relevance does this story have to Galactic Recycling?


None.

I was just checking up on your claim about Einstein thinking the Milky Way was the universe. This shows it is certainly possible he thought in such a way earlier in his life.
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Re: Cosmology and its problems

Postby Eclogite on August 18th, 2017, 6:14 pm 

hyksos » Fri Aug 18, 2017 8:59 pm wrote:How is any Steady-State theory viable in a universe where stars die?
Could Galactic Recycling reproduce stars ad-infinitum?
Are galaxies perpetual motion machines?

Your thoughts ...
I never had any problem with Hoyle's SS universe. In some ways I prefer creating matter one atom at a time out of "nothing" rather than everything in one go, out of "nothing". I find an eternal, steady state universe much more statisfying philosophically. It's just unfortunate that the current evidence is overwhelmingly against it.
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Re: Cosmology and its problems

Postby BurtJordaan on August 19th, 2017, 3:14 am 

bangstrom » 18 Aug 2017, 19:04 wrote:Our observations of the universe appear to be telling us that the universe is much older and larger than predicted by the Big Bang theory.

Huh? All BB-like theories predict a universe orders larger than what we can observe. Likely infinite!

Also, if the 2.7K temperature is entirely due to residual heat from the Big Bang, that implies that the temperature of the universe originating from the stars in deep intergalactic space is zero K. It seems unlikely that the intergalactic temperature of a universe filled with several billion galaxies should be zero.

No, the CMB radiation is easy to distinguish from other sources in the universe, firstly because it has a redshift of z~1100, while the oldest galaxies sit around z~12. Secondly, it comes from otherwise 'black' patches and only in microwaves. It is orders of magnitude brighter in microwaves than any possible source out there, plus it is incredibly uniform.

No contest.
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Re: Cosmology and its problems

Postby bangstrom on August 19th, 2017, 6:27 am 

BurtJordaan » August 19th, 2017, 2:14 am wrote:[
Huh? All BB-like theories predict a universe orders larger than what we can observe. Likely infinite!

Yes, both expansionist theories and common sense tell us the universe is far larger than what we can observe since we can only observe a limited distance and what we see is essentially ‘looking far back in time’ and not a ‘real time’ view. Estimates for the size of the universe are around 90+ billion light years in diameter based on a universe with an estimated age of some 13.8 billion years. I suspect this estimate is far too young and an older universe would consequently be an even larger universe. This is why I say the universe is likely much older and larger than than currently predicted.

BurtJordaan » August 19th, 2017, 2:14 am wrote:[No, the CMB radiation is easy to distinguish from other sources in the universe, firstly because it has a redshift of z~1100, while the oldest galaxies sit around z~12. Secondly, it comes from otherwise 'black' patches and only in microwaves. It is orders of magnitude brighter in microwaves than any possible source out there, plus it is incredibly uniform.

The CMB radiation is a black body radiation and black body radiations tend to lose the identifying characteristics of their atomic source below 5K. Eventually all black body radiations tend to flat line. Radiations coming directly from galaxies are not confused with the CMBR because they come from high temperature sources which are easily identified.

Astronomers once speculated heat from galaxies in deep space should be absorbed and re-radiated from particle to particle and atom to atom over eons of time growing colder with the ages until nothing remained but a ~7 cm microwave radiation at equilibrium and they called this the ‘temperature of space.’ I find it hard to imagine that a universe having more than two hundred billion galaxies could have an ambient intergalactic temperature of 0K. How far from a galaxy would one have to be for a thermometer to read 0K? Also, z~1100 is derived from the length of a microwave it is not necessarily a distance.
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Re: Cosmology and its problems

Postby Eclogite on August 19th, 2017, 6:37 am 

bangstrom » Sat Aug 19, 2017 10:27 am wrote:
BurtJordaan » August 19th, 2017, 2:14 am wrote:[
Huh? All BB-like theories predict a universe orders larger than what we can observe. Likely infinite!

Yes, both expansionist theories and common sense tell us the universe is far larger than what we can observe since we can only observe a limited distance and what we see is essentially ‘looking far back in time’ and not a ‘real time’ view. Estimates for the size of the universe are around 90+ billion light years in diameter based on a universe with an estimated age of some 13.8 billion years. I suspect this estimate is far too young and an older universe would consequently be an even larger universe. This is why I say the universe is likely much older and larger than than currently predicted.
No. That is not what you said. You said this -
"Our observations of the universe appear to be telling us that the universe is much older and larger than predicted by the Big Bang theory."

That is a completely different thing. Your latest statement is an opinion. Your earlier statement is an assertion that claims evidence. If you are retracting your initial statement, fine. If not, what are these observations you claim exist?
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Re: Cosmology and its problems

Postby BurtJordaan on August 19th, 2017, 7:24 am 

bangstrom » 19 Aug 2017, 12:27 wrote:I suspect this estimate is far too young and an older universe would consequently be an even larger universe. This is why I say the universe is likely much older and larger than than currently predicted.

Well suspicion has little legs to stand on in the face of multiple lines of evidence. The 46 billion lyrs across that you have mentioned is only the observable portion's present diameter. We expect that the total is at least 10 times that, possibly infinite. We can also read from the observations that the present expanding phase began some 13.8 billion years ago and that no galaxy or star existed before that. So we consider that time as "the beginning of our universe".

We obviously have no direct evidence of what went on before that time - some form of universe could conceivably have existed before that, so in an abstract sense, you may be right. But we do not consider "before the BB" as very meaningful.

The CMB radiation is a black body radiation and black body radiations tend to lose the identifying characteristics of their atomic source below 5K.

Do you know of any evidence supporting this claim? We routinely observe temperatures in labs that are far lower than 3K.

I find it hard to imagine that a universe having more than two hundred billion galaxies could have an ambient intergalactic temperature of 0K.

Not zero, just negligible in the microwave region of the spectrum. Their are lots of dust and gas in intergalactic space with higher temperatures, but they do not peak at 3K as microwaves, like the CMB does.
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Re: Cosmology and its problems

Postby Sivad on August 19th, 2017, 7:53 am 

hyksos » August 17th, 2017, 6:57 pm wrote:The purpose of this thread is to elicit discussion about the modern state of cosmology , as a whole discipline.


Modern cosmology is the most interesting thing going, I don't really care about the truth I just dig the project. If I was a betting man I'd probably wager that the consensus will be radically altered in a hundred years, but science isn't about the destination, it's all about the journey.
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Re: Cosmology and its problems

Postby hyksos on August 21st, 2017, 3:54 pm 

Amend these statements as you see fit. Nuance them. Get mad. Correct them. I invite such criticism.

1. All steady state theories require a slow creation of new matter.

2. The creation of new stars is not a problem, rather, as long as there is a source of new elemental gas, the laws of physics will eventually get around to making stars out of them.

3. All big bang and inflationary models have some stage where matter is created

4. The creation of matter must come in matter/antimatter pairs. This is a law of physics called CPT symmetry.

5. Whether Steady-State, Big Bang, or Inflation, take your pick, all such theories have a problem of matter/anti-matter asymmetry to deal with. That is, simply adopting a steady-state position does not cure you of this problem.

6. There is no known process in the universe which only creates normal matter with zero antimatter byproducts. This is so clearly understood by physical sciences, (experimentally and theoretically) , that anyone claiming such a process is simply describing something that is physically impossible.

7. Inflaton fields, dark matter, dark energy, axyons. We can have our deeply-felt skepticism about all four of these things. And that's fine. Skepticism is healthy. But unlike CPT symmetry-breaking, we cannot point at any of these as being physically impossible. All four of these ideas are congruent with the known laws of physics. In other words, all four are possible. Matter/antimatter asymmetry is not. Very textbooky, established science tells us that matter cannot be created on its own, but must be accompanied by equal-parts antimatter. This is called pair production.

I am certainly open to listening closely to anyone elaborate and expand on any SS theory where matter is not continuously created. I would ask how such a universe avoids heat death and continues to create new stars ad infinitum. That issue seems far more important than collapse vs expansion vs cosmological constant et cetera. For some strange reason, the history books continue to harp on the cosmological constant like it is pertinent.

What did adherents of S-S (such as Hoyle and Einstein) think was creating fresh new matter to build fresh new stars out of? And how was this process continue ad infinitum? Simple questions.
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Re: Cosmology and its problems

Postby Eclogite on August 21st, 2017, 5:29 pm 

Why are you asking a readership that is likely accepting of BB theory to, effectively, defend SS theory? That seems a bizarre request. If you simply wish to know the answers to the questions read Hoyle's work. It is accessible.
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Re: Cosmology and its problems

Postby DragonFly on August 21st, 2017, 5:46 pm 

Terrence Witt has a steady state universe: http://www.nullphysics.com/pages_cosmology.php

His book now sells for one cent in some places.
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Re: Cosmology and its problems

Postby hyksos on August 23rd, 2017, 2:53 pm 

For a few days now, I have investigated and researched the historical trends in early cosmology.

It appears that the whole crux of Big Bang cosmology pivots around General Relativity. GR is the entire basis of the development of the Big Bang Cosmology. Without GR, you cannot even begin to develop the initial ideas of expanding space. Anyone who refuses to accept that GR is a valid description of physical processes cannot get past 1925.

In 1950, Albert Einstein described what the theory of General Relativity says about the universe. He wrote that GR depicts space and time as a kind of field, and that the field is dynamic. In other words, GR differs from Newtonian physics in a key way. In Newton's universe, "time" was equal to a giant cosmic clock that ticks at a constant rate. All local clocks are equal to it everywhere and forever. "Space" is a rigid, eternal, unchanging grid upon which everything else hangs. Everything is nice and neat about space. All angles are at 90 degrees, and all coordinates are forever in their rightful place.

General Relativity says otherwise.

GR says that space and time are a single entity called spacetime, and that this is a type of field described by a dynamic manifold. It is a changing entity. Einstein's field equations are an abstract description of the shape of this field/manifold, as determined by the mass and energy contained within it. If a particular distribution of matter is assumed, one can solve the field equation to obtain a solution. The solution is called a "metric". The metric determines how a local observer inside the field will measure distances.

An early example of a solution to Einstein's equation was one obtained by Alexander Friedman ( a skinny russian physicist operating out of St. Petersburg). For technical reasons, it was presumed that certain solutions to Einstein's field equation must be referring to the entire universe, rather than some local region within it. Friedmann assumed that the density of his toy universe was isotropic and homogeneous, and that it's compression properties followed that of a liquid. The equation admitted two solutions : 1) A contracting universe or 2) An expanding universe. This was completed in 1922.

Similar solutions were later attempted and succeeded by a cluster of other physicists. Among them, Alexander Friedmann, Georges Lemaître, Howard Robertson and Arthur Walker.

Lemaitre was an ordained priest in France. Prior to pioneering work by Edwin Hubble regarding redshift, Lemaitre himself referred to the Big Bang as the "Theory of the Primordial Atom". On a radio talkshow, Fred Hoyle facetiously referred to "... these boys are saying there was this big bang ..." Sometime since then, Big Bang was adopted as a scientific term.

In any case. The universe is presumed to be a very large dynamic manifold whose behaviors are governed by the predictions of General Relativity. From that vantage point, it is later inferred by disciplined means, that the universe is expanding. The redshift of very distant galaxies acts as experimental verification. The farther away a galaxy is, the more it is redshifted its light has become, because the light has passed through more expanding space on its way to the earth.

I am not advocating the truth of any of the above. I am a dispassionate neutral journalist, merely reporting on the history of the science.
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