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Bill S. #54282 08/10/15 11:33 PM
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Originally Posted By: Bill S.
I don’t have theories; I lack the necessary maths/science to formulate one effectively. However, I’m willing to have a go at an idea. If nothing else, I can learn from having it dismantled.

You don't need maths/science to formulate an effective theory that is layman thinking. Einstein for example actually wasn't that good at mathematics he needed his old school teacher Hermann Minkowski to actually do the mathematics for GR. What you need is concise logical idea that holds together. I rarely ever use mathematics to "prove" anything even with experts. You should remember my exchange with PMB, he wasn't happy but I got him to show you the real problem not the problem via some mathematical abstraction. I often use mathematics to find problems but once you identify the problem it's usually easy to then work out an experiment or result that will falsify an idea.

Originally Posted By: Bill S.
Why do we not have runaway gravity?

This is the wrong question; it should be, “Do we have runaway gravity”. This has a straightforward answer: “Yes”.

Cool so now we have a working concept.

Originally Posted By: Bill S.
The range of gravity is infinite, so however far apart the galaxy groups become, gravity will eventually catch up.

You don't have a problem with this the whole range is infinite thing? Remember that means gravity has to propagate outwards as a negative attractive force like electric charge.

Is there an advantage over that formulation over doing the QFT thing and inverting it and putting a field everywhere and get rid of the infinity propagation, just a question and thought.

Originally Posted By: Bill S.
This may be indistinguishable from the closed universe concept, but it has nothing to do with the basic geometry of the Universe. It is runaway gravity, caused by the fact that gravity creates more gravity, so gravity will eventually overcome any basic geometry.

Okay I would like you to read an article from Ethan on Dark matter.
Strangely ignore the DM stuff and concentrate on understanding the normal matter behaviour.
https://medium.com/starts-with-a-bang/as...es-c5b6d90b1883

It hopefully will ring some bells.

One may also question if a big bang is possible under your idea, what would cause the matter to spread if it was already clumped in a big bag scenario with gravity as you describe?

Last edited by Orac; 08/11/15 04:12 AM.

I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.
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Orac #54283 08/11/15 08:31 PM
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Originally Posted By: Orac
You don't have a problem with this the whole range is infinite thing?


What? Me! Have a problem with infinity? Seriously, though, I’m trying to use infinity as others use it.

I like Ethan’s article. So far I’ve only skimmed it, but the idea that gravity needs help in forming atoms, stars etc raises two questions for a start:

1. Is this main stream scientific thinking?

2. If so, why is it not more widely acknowledged?


There never was nothing.
Bill S. #54284 08/12/15 03:06 AM
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See you have progressed, there was a time you would take him as gospel. I take it you see more than few problems with that article.

"Is it main stream" would be a Bill G question, Ethan is part of the glossy science media so I guess it is smile

You realize you are doubting a qualified scientist in his area of expertize, Rede and Bill G will be after you smile

If you asked me as a janitor and rebel do I believe Ethan's answer then bluntly NO.

Working from first principles dark matter would clump together just not as fast or easily as matter. When normal matter is orbiting in an accretion disk the various interactions and collisions will cause the matter to heat up, and that heat will radiate energy away (the key words never mentioned). The result is the orbit decays and the process quickly escalates and that was main stream back in my day.

If dark matter doesn't interact with itself there is no mechanism to speed the accretion and hence no mechanism to to decay the orbit. That is the key difference between normal matter and dark matter and something completely lost in that whole article from Ethan.

This would present a view with dark matter that would orbit a black hole for all time, sort of like a world without friction. So actually over time you would end up with more and more dark matter trapped around black holes and the larger gravitational bodies.

Now that is actually a problem on two fronts
(i) Observationally there is a strong correlation between the rate of consumption of normal matter and the estimated mass gain of feeding black holes and little from dark matter.
(ii) Dark matter would and should end up as the dominate mass around a black hole

When you simulate it that is exactly what happens
http://www.dailygalaxy.com/my_weblog/2015/06/nasa-black-holes-are-dark-matter-concentrators.html

Observationally as Ethan says that is not what dark matter looks like in the universe, so how do we fix it. Well you create the concept that if you clump dark matter together in large enough density it self annihilates releasing positrons. So we go from absolutely dark matter to weakly interacting dark matter

Originally Posted By: http://www.dailygalaxy.com/my_weblog/2015/06/nasa-black-holes-are-dark-matter-concentrators.html

Over the past few years, theorists have turned to black holes as dark matter concentrators, where WIMPs can be forced together in a way that increases both the rate and energies of collisions.

Then if you go looking for that positron signature and you find it
http://www.americaspace.com/?p=33651

Now you are convinced aren't you smile

Last edited by Orac; 08/12/15 03:54 AM.

I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.
Orac #54286 08/13/15 08:03 PM
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Time is extra short at present, but I'm still here, just.

My main questions about Sean's article would be:

Does gravity need help to concentrate ordinary matter beyond the stage that Sean indicates?

If so, where is the evidence?


There never was nothing.
Bill S. #54287 08/14/15 12:36 AM
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I will give you the little joke on classical science zealots that don't believe in QM, that the universe actually can't exist then smile

I won't bother to write it all out again "ask a physicist" does a reasonable layman job
http://io9.com/5561717/ask-a-physicist-why-dont-collapsing-atoms-destroy-all-matter-in-the-universe

The technical name for it is degeneracy pressure.

The name doesn't translate well to me, that English thing again, but it is not up to me smile

The section on it in wiki isn't fantastic
https://en.wikipedia.org/wiki/Degenerate_matter

One of the funnier things to realize is the reverse situation in a solid.
If there is QM degeneracy pressure why doesn't a solid expand infinitely outward smile

Answer if you get stuck:
http://www.physicspages.com/2013/05/28/degeneracy-pressure-in-a-solid/

I hope you have a new appreciation for solids now. I would also hope you roll your eyes when someone says QM doesn't matter when things become large and solid, I have seen a couple of people do that on this forum.

The irony is the "classical physics world" is a delicate balance between various QM forces in remarkable fine tuning.

Our universe without QM wouldn't last very long (a few billionth of a second), yet some want it gone smile

The memo here is you can't tack QM into a classical world as a bolt on extra strange effect, you would have to completely replace it along with the classical world in a theory of everything.

Last edited by Orac; 08/14/15 04:55 AM.

I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.
Orac #54288 08/14/15 01:53 AM
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David Kaplan has done a nice video on falling into a black hole but wont add to anything you already know.

https://www.quantamagazine.org/20150508-what-happens-when-you-fall-into-a-black-hole/


I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.
Orac #54293 08/17/15 09:15 PM
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https://en.wikipedia.org/wiki/Degenerate_matter

Quote:
In particular, the pressure remains nonzero even at absolute zero temperature.


Does this imply that if the pressure were zero it would, in principle, be possible to determine the position and momentum of a particle in contravention of the uncertainty principle?


There never was nothing.
Bill S. #54294 08/18/15 12:21 AM
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Yes and more importantly if you cool anything to absolute zero it would collapse, something that worried science in the 1920's with the universe temperature at 3K smile

So it is basically a statement of stability and QM still persisting even at absolute zero and hence the pressure remains and things don't collapse. QM even predicts how these things behave together as a solid and apart in so called Bose-Einstein condensates.

Some of the brighter students who haven't yet encountered QM but doing classical binding theories will often ask this question.
"Can Absolute zero temperature, cause the formation of a black hole?"
If you look carefully at what they are studying the reason for the question is obvious, and you sometimes get the next question.
"Is there such thing as Absolute hot temperature?"

Quantum physics formally sets infinitely negative to infinitely positive temperature range. The spin system in matter stops matter reaching either infinity. To beat the natural limits requires rather exotic experimental setups which has been done in the lab at least for colder than absolute zero. Such things are "toys" to prove things they could never occur naturally.

If time ever did stop you should now be able to work out what would happen to the universe or at least all the matter in it. Ponder for example people who want for time to really stop at the event horizon of a black hole, they do not really understand the implication smile

I would hope you also get why materials may expand or contract as they are cooled and you alter the balance of the opposing forces. Classical science long struggled with water expanding as it was cooled, they got that water changed into a hexagonal form but could never fully understand why. It also required a bit of hand waving (and sometimes funny wrong) as to how ice could generate massive forces to expand and explode glass containers in freezers etc. Today we know those forces can reach a mind numbing 300 Mega Pascals and what they are.

If you are interested in the classical version
https://en.wikipedia.org/wiki/Negative_thermal_expansion

Explaination in classical physics
https://en.wikipedia.org/wiki/Interatomic_potential

However note the warning at the bottom
Quote:
Classical interatomic potentials cannot reproduce all phenomena. Sometimes quantum description is necessary. Density functional theory is used to overcome this limitation.

I must say I am impressed that you are not only understanding the details but are able to extend and work out things that aren't explicitly stated. You are not jumping at individual new facts but looking careful how and if that fact fits into a framework, a sign you really are getting it.

Again my message is simple, QM is not an addition bolt on to classical physics but that classical physics is a sometimes valid simplification of a QM universe. None of this stuff is hard to understand it is only the mathematical calculations that are intense and why we still teach classic physics.

Last edited by Orac; 08/18/15 06:04 AM.

I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.
Orac #54295 08/18/15 05:37 AM
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Another line you may choose to look at, so I will put in this new post.

Given what you have understood from above lets discuss an option QM throws up with black holes which rarely gets glossy media presentation

http://phys.org/news/2011-03-black-holes.html

You should sort of understand the process now that would drive the explosion. For completeness the details and mathematics is accurately done here
http://physics.stackexchange.com/questions/159937/why-would-a-black-hole-explode

So basically QM poses a possible view that a black hole can only exist so long as it can keep feeding on matter. Starved of matter it will evaporate energy until it reaches a critical size and explode.

Recycling at it's best smile

If that interests you then you can extend the theoretical construct to a different form of big bang
https://en.wikipedia.org/wiki/White_hole

I would be interested to know if you had even heard of the idea black holes might explode rather than just evaporate?

Last edited by Orac; 08/18/15 06:03 AM.

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Orac #54301 08/22/15 10:45 PM
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The reason I have been absent from this thread for a while is not lack of interest.

your link: http://phys.org/news/2011-03-black-holes.html starts with a mention of Hawking radiation. In principle I know what it is, but one thing that puzzles me is that the event horizon of a BH is always presented as a zone in which conditions change slowly. Hawking radiation seems to require it to be a surface of such precise location that it can separate something as closely spaced as a particle/antiparticle pair. What am I missing?


There never was nothing.
Orac #54302 08/22/15 10:59 PM
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https://en.wikipedia.org/wiki/White_hole

Interesting link. In a multiverse scenario, could a white hole simply be the "other side" of a BH, in another universe? Entropy would then be conserved in the multiverse, if not in individual universes.


There never was nothing.
Bill S. #54303 08/23/15 03:56 AM
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Originally Posted By: Bill S.
your link: http://phys.org/news/2011-03-black-holes.html starts with a mention of Hawking radiation. In principle I know what it is, but one thing that puzzles me is that the event horizon of a BH is always presented as a zone in which conditions change slowly. Hawking radiation seems to require it to be a surface of such precise location that it can separate something as closely spaced as a particle/antiparticle pair. What am I missing?

You are actually missing nothing and actually asking the sorts of questions that need to be asked as far as I am concerned smile

Hawkings himeself seems to have thought along the sort of thinking line with his grey holes.
http://news.discovery.com/space/no-black-holes-more-like-grey-holes-says-hawking-140124.htm

The problem to me is you create a particle/antiparticle pair those two pairs both create gravity under GR and I know you know that story. So one particle drops back in, one doesn't clearly you dissipate the gravity energy and we just did Hawking radiation with no mathematics and no concern what the interface looks like and our problem still exists.

Ok my thoughts the real problem to me everyone is dancing around is time=0 at the event horizon. That is the only reference frame available and it is strictly forbidden to use it under GR you saw that with the double slit experiment. So whatever GR is saying we can ignore exactly like the double slit situation, it fails because it is a classical theory.

What strikes me is we actually have another interface that is somewhat the same as this just a lot smaller at the atom level. What happens inside that interface is a very different to the outside and can not be described by classical rules. Classical physics sort of works down to that interface and then you have to just ignore classical physics.

I actually ponder whether the event horizon around a black hole is not just a larger version of the same thing, just ike the surface of earth is an interface and we need to adjust formula for inside (shell theorem). I would like to see a lot more justification discussion on why you can take GR inside the event horizon, it's like our crazy attempts to take classic physics inside the atom and inside the earth and you get stupidly wrong answers.

So your logic and understanding is what I call mainstream science and it goes from the atomic interface to the event horizon of a black hole. I have to stop at the event horizon as you have reached the limit of my understanding of GR and I really don't feel comfortable to go beyond it.

Last edited by Orac; 08/23/15 04:42 AM.

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Bill S. #54304 08/23/15 04:01 AM
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Originally Posted By: Bill S.
https://en.wikipedia.org/wiki/White_hole

Interesting link. In a multiverse scenario, could a white hole simply be the "other side" of a BH, in another universe? Entropy would then be conserved in the multiverse, if not in individual universes.

It's in the article Hawkings actually argued pretty much that

Quote:
This may imply that black holes and white holes are the same object. The Hawking radiation from an ordinary black hole is then identified with the white-hole emission.

His basis is exactly yours and you are now really showing you have pretty much understood it all.

That really was an extension exercise and I am so impressed you got it and made the connection.

See it really isn't that hard smile

Last edited by Orac; 08/23/15 04:41 AM.

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Orac #54315 08/25/15 03:19 AM
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Bill S ... this paper got written up by glossy science media today and I would like you to evaluate it.

So our background is as we discussed the real situation in a solid is you have two opposing QM forces both trying to do opposite things. Our glossy science media can't even give the reader that background, but you have covered it so at least will understand the context.

So here is the glossy science media article
http://phys.org/news/2015-08-iron-bar-capable-decision-making.html

Here is the actual paper
http://iopscience.iop.org/1367-2630/17/8/083023/article

Ok I would like you to evaluate both the report and original paper.

No hints this time smile

Last edited by Orac; 08/25/15 03:21 AM.

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Orac #54316 08/25/15 02:25 PM
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Had a quick look at both links. Will have a better look as soon as I can. Hope you don't expect me to understand the maths in the actual paper. smile


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Orac #54318 08/25/15 08:50 PM
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Just had a look at the first link. My initial reaction was to look at the date in case it was 1st April.

The original article may show what is really going on, but Gell-Mann's "quantum flapdoodle" comes to mind.

Watch this space. laugh


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Bill S. #54319 08/26/15 01:06 AM
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I had the same reaction smile

I will give you the background it comes from Quantum Information Science and I thought you might pick up the problem they were trying to understand and badly propose a solution to.

Ok this problem exists in both classical physics and quantum mechanics with solids. The question is how does a solid hold it's shape and volume given the fact it actually moves around with expansion and contraction. Having a rigid lattice structure does not solve the problem as you input or remove energy to flex the structure, that energy when restored must result in the structure returning to original position.

In solids the expansion and contraction may not be the same rate in every direction (even rate of movement is called isotropic). So as you cool the object how does it work out how much energy to return to each area. Think about cooling one end rather than the body as a whole and yet you get the same result when you let it reach equilibrium.

In classical physics you know the first order approximation as Hookes law
https://en.wikipedia.org/wiki/Hooke's_law

So one of the current interests in QM is to derive Hooke's Law on a microscopic level inside QM.

Note it is a "law" not a theory in classical physics there is no real complete explaination of why it works all you can do is a lot of hand waving and speculation. At school level you claim the energy just goes into the interatomic bonds (that is lie) wave hands and quickly move on. Teachers may need to make sure they have sent any smart students on an errand before discussing.

In QM the area is called Density Functional Theory (DFT) and as you see it's a theory not a law.
https://en.wikipedia.org/wiki/Density_functional_theory

I take it they are trying to adapt DFT into Quantum Information Theory but I am not convinced that model really works smile

Coming from a science modelling background lets just say there are models and then there are models.

Mind you, I choose to maintain my body shape by a highly efficient algorithm does sound cool laugh

Last edited by Orac; 08/26/15 02:33 AM.

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Orac #54341 08/27/15 03:28 PM
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A crystal lattice forms because atoms combine to form molecules, and molecules combine to form a lattice. Without outside interference the process works faultlessly. If energy is removed, the lattice deforms. Even if the deformation is non-isotropic, the deformation in any direction is related to the bond strengths in the lattice. When the energy returns, why would the factors that originally formed the lattice not cause it to return to its original form?


There never was nothing.
Bill S. #54346 08/27/15 05:56 PM
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LOL thats the theory and it works really well if you say it fast wave hands and move on smile



https://en.wikipedia.org/wiki/Atomic_diffusion

That is why technically when you heat and cool anything over a large enough range it is never the same and why you get thermal fatigue even in the purest materials.

When you deal with complex materials you have micro crytals and this stuff gets even more mixed up and it has it's own discipline called material science.

The general problem in that is called heat treating
https://en.wikipedia.org/wiki/Heat_treating

Again what we think of as a very still lattice in classical physics isn't very still but it is a nice easy model to teach.


I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.
Orac #54348 08/27/15 09:38 PM
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I had a feeling you would say I was thinking like a geologist. smile

The only real thought I have given to lattice vibration (and phonons) is in relation to the apparent slowing of light in a medium. Obviously I need to do some more thinking.


There never was nothing.
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