Exposing the Myths of Settled Science

ErosA433
It is like maybe saying that, when all forces where unified at the start of the big bang, that time itself didn't exist, and that the universe was started, the big bang was started as result of time starting to move forward. That as time started to move 'forward', space condenses out of it, and then matter condenses out of both space and time, and matter and energy are the lowest configurations of the system.

I am of the view point that the word time is not a word used to describe a thing, but that time is only a quality or aspect of energy/matter. Which is similar to the way you described it, but all this stuff is always iffy saying what caused what and chicken and the egg stuff, like when you say 'time' started to do something, and space condenses out of time, to me this is meaningless. If we imagine the pre big bang universe as 1 whole object/substance with no area or plancks length of difference throughout, and no movement throughout, this state it would be able to be said that 'time' does not exist, because there would be nothing to distinguish one moment from the next, there are no causes or affects, there is no change. So imo time is only the transformation of energy, the 4th dimension, energy exists in 3dimensions as a shape, the changes it undergoes is the 4th dimension of its existence. So this is why the biggest problem with physicists is trying to explain how energyless,timeless,nothingness turned into energyfull,timeful, everythingness.

ImaFungi


I think the problem with the interacting edge model is that it is quite difficult to define an edge, because the gravitational field as determined by only the matter contained within a set radius predicts that velocities should fall off, it is quite easy to deduce this from quite a simple model of a disk governed by internal mass rather than the disk being a solid object. And that is not what we see. Now when it comes to edges of galaxies interacting with other galaxies or even just space itself, once more this effect occurs very deep into the galaxy itself in visible light and extends far out beyond what you might call the visible edge. so it is something that penetrates the whole galaxy and doesn't appear to be an 'edge only' affect.

On the Halo, yes, so draw a circle on a page... and draw a line through the middle of it horizontally. Now at about half the radius , with a thick pen, draw a line along the horizontal one you drew and a big spot at the centre. What you just drew is a very simple representation of the structure of a dark matter halo with a galaxy sitting in it looking at it edge on (this is obviously for a spiral only. Imagine the large circle as a sphere, and the galaxy a disk suspended in it line a marble with a swirl in it.

The Dark matter halo is modelled as an integral part of the galaxy, and not just at the edges or along the disk. it is a surrounding blob of matter. If you model that as roughly uniform in density, what you find when you model and predict using simple newtonian mechanics, you predict the correct rotation curve.

Ok interesting. Well it doesnt matter if its hard to define an edge or not, or if the edge it self is in constant flux and not so smooth and clear cut, there is an edge there because thats how gravity wells work do they not? And the well wall is steepest or most potential gravitational energy towards the center? To me its just a very easy thing, too easy, to say, oh it must be that there is a large enough amount of matter that we cant detect to solve this missing mass/extra gravity problem. I think our non understanding of fundamental space, which equals lack of understanding into the true nature of gravity, which also relates to lack of understanding in dark matter, which also relates to this discrepancy in comprehension of why there is this gravity problem/need for dark matter solution. So just from an intuitive layman perspective, a person who likes to behold the universe in my mind and imagine things like how a gravity might be traveling through space, and what the black hole might really be like, and how gravity works, I really think there might be something to the idea of (like in going wave meets outgoing wave, a novel event occurring at their interaction) of the galaxy spiraling, its gravity well spinning as well (imo most likely this occurs and impacts how the mechanism of gravity works) the solar systems being kept in order by swirling around this gravitational energy gradient; another potential idea related is that as the stars and planets swirl around this if it is not a perfect circle around the galaxy, would this insiuate that some momentous energy from the solar system is given off and could that add to gravity?

...So the black hole makes the main gravity well and all the stars swirl around, and they make their own gravity wells, which adds to the collective, but if they are not orbiting perfectly circular, could their mass swaying to and fro push 'gravity' waves inward and outward, and could this momentum of gravity additionally add to the over gravitational extent of a galaxy?

Well it surprises me to if you have been in physics long that you say we haven't a clue. We have a pretty good grasp on a great deal of the universe. There are of course still some very very large questions still to be answered. It is patently incorrect however to say "Because we don't know 100% we don't know anything"

It also surprises me if you are in the field of physics that you have never heard of experimental particle physics. Even if you are in another field, i can think of a great many fields.

Soft condensed matter physicist
Solid state physicist
Plasma Physicist
Particle Physicist (branches in to theoretical particle physics and experimental particle physics)

I think you can see were I am going with this.

No I don't work at CERN, but there are a great number of labs around the world host to particle physics that don't have to involve accelerators. Furthermore, accelerators are not the obvious way to search for dark matter. yes you can attempt to make it, but that assumes that there is a direct coupling path in which you do make it.

I work at one of the deep underground labs around the world

www.deepscience.org...

Of which there are a few as you can see in that link.

Which field do you work in?

ImaFungi
To me this is just 1 of many easy logical thoughts, that perhaps there is a reaction at that edge of the gravity well (similar to potential reactions at a black holes event horizon) that causes the outer stars to rotate in the originally surprising manner.

I'm not sure why you think that's a logical thought...it completely contradicts the data on galaxy rotation, which measures rotation at various distances from the galactic center:

ruxandrab.blogspot.com...#!

In the diagram there are measurements at all those other points leading up to point "A", not just the measurement at point A. If there was some kind of edge effect there would be a jump in the curve at point A, and there isn't.

reply to post by Arbitrageur


Perfect, I found a diagram but wasn't happy with it, but that is a great one to explain it had my back on that one

reply to post by ImaFungi


Egg came first!!

reply to post by Arbitrageur


What I proposed is a reason why there is no jump. Tell me if I have this right; the reason physicists were surprised with the data is because the outer stars were revolving with more velocity then expected (would this be akin to if we measured the mass of the sun, and used our gravity equations on all the planets and discovered pluto was orbiting the sun faster then it should?)?

reply to post by ImaFungi

Obviously (at least I thought it was obvious) the bottom graph that says "expected" shows what is expected in a galactic rotation curve without dark matter, and yes on a smaller scale if you plotted the planets in our solar system, and what is pluto now, a "dwarf planet"?, you would get something like the expected curve where for example Pluto could be point B, as the rotation velocities of the planets in our solar system are not dominated by dark matter, it would follow the expected curve, but not exactly of course since our inner solar system is not like a galactic core.

But there is no sudden jump in the expected curve either, so I really don't follow your thought process at all regarding an edge effect, in relation to these curves and the data. I do understand black hole event horizon but I see no analogy to that in galactic rotation curves. How do you figure an edge effect means there would be no jump in the curve; that makes even less sense?

reply to post by ErosA433

Thanks, I thought it might be helpful.

It was brave of you to try to answer those mostly unanswerable questions. I'm surprised dragonrdr never heard of your field...there's even an ATS thread abut the expansion of SNO to look for dark matter:

Canada's first dark matter lab opened today: Look out CERN meet SNOLAB

What ever it is observations point at it being, a very weakly interacting particle, it might not even couple to our known particles at all, there is nothing theoretical that says it must... it would be a shame...

Wow, I never even considered that possibility, but yeah that would make it hard (impossible?) to detect.

Great link here too... for those interested in a walk around SNOLAB

www.snolab.ca...

Yeah that is a concept that many here might say "You physicists are so sold on your ideas" But not quite so, even we acknowledge that, there might be a possibility that this dark matter is impossible to detect, because theoretically it might not couple to the forces we know (other than gravity). It could be something totally sterile and different. Thats what makes it fun Explore the unknown.

Take a look at number 19 on the map That is the SNO detector... the old girl that is made from acrylic and bonded underground.

Ever been to an aquarium with the whole "tunnel of water" which is made completely out of acrylic. Yeah so the company that was involved with developing the bonding techniques for SNO, basically went on to be the world experts in acrylic bonding, and nearly all such aquariums are done with the technology developed back in those days.

reply to post by Arbitrageur


Well my thought process is that, it is possible the reason outer stars have the revolution rate they do due to an energetic/field reaction between the 'event horizon'/outer edge of a spiral galaxies gravity well and the incoming outer galactic space and dark energy. There could be some novel interaction there that urges the outer stars to stay in spiral rotation instead of flinging off into space, and that interaction could be 'dark matter'/dark matter halo.

reply to post by ImaFungi


I am curious do what you mean by spiral rotation?

Stars in galaxies are probably orbiting in approximate circles (most accurate is to say elliptical) orbits with perturbations caused by local matter density fluctuations. There is no real inward 'spiral' motion. The spiral arms are actually a density wavefront that causes rapid star formation, the brightness is attributed to this star formation.

reply to post by ErosA433


I didnt mean spiral (as in increasingly smaller or larger orbits 2/3 dimensionally, though technically a 4 dimensional spiral could have relatively equal orbits as time progresses which I guess is how I was thinking about the galaxy), I meant orbit I guess. But anyway, minor point (though for some reason you will probably haughtily say, ahem... its not such a minor point), did I ask other questions in my previous response to you and will you consider trying to answer them?

ErosA433
Being an experimental dark matter physicist is simply that I am currently involved at a large level with the development and construction of a next generation dark matter experiment. It is my current work.

Just curious ,whether in these dark matter experiments, you address man's chronometer time/ and or the universe's own ambient time, if at all?

oh no there was no pre-judgement it was that i have seen the spiral statement before on ats and it was meant in a spiral like water down a plug. I just wanted clarification rather than a want to belittle or berate.

There are alot of questions which are very difficult to describe, even as a physicist. Many of these questions are fairly fundamental ones that we are all wondering about. All we can do is describe a "best scenario or analogy" which can be understood.

the condensing space out of energy and time is one such example. It is a little bit like saying that at the beginning there was only energy, and that space and time didn't exist separately, It was all unified. The time starts to move forwards and space begins to expand. As space-time separates there is a enormous release of energy but the system is cooling and expanding. So the release of energy as the space and time separate drives rapid expansion of space through the inflation period. Once the two are fully decoupled and energy output from this process reduces the expansion is no longer driven at as rapid a pace. This occurs at in GUT theories and occurs at extremely small timescales and at extremely high energy. GUT is Grand Unification Theory, it states that all forces in the universe unify into a single force at high energy. This is already observed in electro-magentism and weak interactions.




Regarding the dark matter thing, the issue is really that a galaxy doesn't have a defined edge. An event horizon is not really a physical barrier, it is just an imaginary spherical limit at which light travels in full orbits around the compact object. Any closer and it goes inside, any further out and it can potentially escape. What is on the inside? Again there are many many models to describe this, and there are lots of problems to solve. These models are very complicated and mathematically heavy. Theorists go to great lengths to try and describe mechanisms for phenomenon that we have observed, such as the production of jets, how mass accretion occurs and what the internal structure is formed and what properties they have. All questions are on the table and a great many people write papers and papers and papers on the subject.

Because there are as many theories as there are days in the year, it is difficult for me, who isn't in the field of black holes, to say what is right wrong or the best model.

so back to a galaxy, there is not edge to speak of, only a gradual increase in matter density. The idea of there being an edge to our solar system is that the solar wind interacts with interstellar medium and a termination shock is generated, representing when the solar wind 'stops' and diffuses into the interstellar medium. For a galaxy, there is no barrier. The galaxy represents a high matter density and outside the galaxy is a low/very nearly zero matter density. There is no shock front, or force barrier that I can think of existing. Even the depth of the gravitational well out that far will be extremely shallow (without dark matter). The gravitational potential out at the edge of a galaxy, should be extremely low, and the fact that we observe orbital motion that shows it is higher than theoretically possible via baryonic matter makes us think that something else is happening.

Gravitational field interactions sounds very vague and you might imagine, since gravity appears to be additive, that anything at the edge requires there to be mass too. or at least that you expect galaxies that belong to clusters to interact differently. Truth is that they dont, all spiral galaxies appear to exhibit this fast rotation, and truly, Dark matter is one of the most simple ways of explaining what is happening in a coherent model. Iv read about modified gravity, but again it appears convoluted, with effects and corrections that appear to be little more than "bodge" factors that have no physical derivation, the models also have to be fine tuned for each galaxy, where as the dark matter halo has only a couple of tuning parameters completely to do with the shape / flatness of the halo.

Sorry if my reply doesn't answer all questions, I think asking questions is a great thing, and I am constantly asking myself in the corse of writing some of these posts... Is this correct? is this the best way to describe it? is it a good level of detail. What are the other theories/options. It is also never my intension to insult unless I have been insulted or directly attacked in a petty way. Even then i try to avoid it. So my egotistical post regarding PhDs and fields of science does come across as being a big headed idiot, but is simply a response to something that i thought was very strange and hard to grasp when a person claims to be in physics for a long time and has never heard of what i would consider in the field of dark matter and cosmology to be very obvious and then miss the mark a little mentioning the first particle physics related institute that comes to mind. Once again, this is not meant to insult, It is just an honest enquiry to the level of experience there is around here.

further more, as a professional scientist I do not expect anyone to listen to me, and I don't expect anyone to take my words as some kind of ultimate knowledge passed down... I expect however that people exercise a basic level of logic and sensibility. It is with a very heavy heart that I see ATS, and i read posts by people who truly believe that they are onto something, but the truth is that they have not even learnt 5% of the subject and they are already believing that they are at the boundaries of the field. Hey, guys, I have a PhD and Id never claim to know even a fraction of the field... But what I do in my area, does allow me to get closer to the real edge of science and it is extremely exciting and rewarding (not financially though)

reply to post by Angelic Resurrection


What do you mean? I am not sure of the question being asked. Most dark matter experiments are cryogenic detectors that look for dark matter interactions. rare event searches basically. Not completely sure about the question of time however.

ErosA433
Well it surprises me to if you have been in physics long that you say we haven't a clue. We have a pretty good grasp on a great deal of the universe. There are of course still some very very large questions still to be answered. It is patently incorrect however to say "Because we don't know 100% we don't know anything"

It also surprises me if you are in the field of physics that you have never heard of experimental particle physics. Even if you are in another field, i can think of a great many fields.

Soft condensed matter physicist
Solid state physicist
Plasma Physicist
Particle Physicist (branches in to theoretical particle physics and experimental particle physics)

I think you can see were I am going with this.

No I don't work at CERN, but there are a great number of labs around the world host to particle physics that don't have to involve accelerators. Furthermore, accelerators are not the obvious way to search for dark matter. yes you can attempt to make it, but that assumes that there is a direct coupling path in which you do make it.

I work at one of the deep underground labs around the world

www.deepscience.org...

Of which there are a few as you can see in that link.

Which field do you work in?

Well i work with medical physics in Tennessee should narrow it down enough for you to figure out where. Any way no a colleague of mine we were joking how physicists seem to be popping up and everyone wants there own title. I wont go in to the jokes but you kinda fit right in when you said dark matter. Ill just say if you have ever worked with one of the labs such as nolab we have probably been in contact.

So My guess for you Sanford neutrino research am i close? you dont have to answer that any way welcome aboard ive had a hard time keeping up with people on this thread.

Arbitrageur

ImaFungi
To me this is just 1 of many easy logical thoughts, that perhaps there is a reaction at that edge of the gravity well (similar to potential reactions at a black holes event horizon) that causes the outer stars to rotate in the originally surprising manner.

I'm not sure why you think that's a logical thought...it completely contradicts the data on galaxy rotation, which measures rotation at various distances from the galactic center:

ruxandrab.blogspot.com...#!

In the diagram there are measurements at all those other points leading up to point "A", not just the measurement at point A. If there was some kind of edge effect there would be a jump in the curve at point A, and there isn't.

Well the inverse square law tells us observed mass in a galaxy isnt enough to keep those outer edges locked in place unless mass is much higher then observed. Thats why on computer models they literally fly apart contradictory to observation. And your right on another thing a gravity well doesnt have an edge just keeps decreasing until it can no longer be detected.

ErosA433
reply to post by Angelic Resurrection

 

What do you mean? I am not sure of the question being asked. Most dark matter experiments are cryogenic detectors that look for dark matter interactions. rare event searches basically. Not completely sure about the question of time however.

Most people dont understand the way physics looks at time tried explaining this to my son not to long ago. I started with this quote

People like us who believe in physics know that the distinction between the past,the present and the future is only a stubbornly persistent illusion" Albert Einstein

See time in physics can be different things depending on the discipline to some its merely an equations to be factored in being one of the fundamental forces. Then there is general relativity which makes it a 4th dimension.In Einsteins world we have a block universe everything happens all at once with eddies occurring as new events occur. This is why we have no idea why time seems to prefer one direction over another. Though if you have ever read Stephen King he had one in the langoliers. Any way bottom line is we have no idea what time actually is we just know its there because our equations tell us it has to be. This is where i had to get in to observers with the talks with my son and then about two hours as he tried to create paradoxes.

reply to post by ErosA433


Thank you for that long and thoughtful reply, its hard for me to try and follow that up, but I still want to probe my idea.

First of all is the central super massive black hole the center of gravity of the galaxy system, and does that mean it is the vocal point of mass and so it is the object that is doing 'the most original momentous movement' ( that is to say it is moving and everything else around it moves because it moves)?

All I am saying is that, the space in between galaxies is a force of expansive energy, dark energy, and is accelerating; Spiral galaxies are rotating through/in this space; I understand there is no edge to the solar system, but it is certainly possible or even likely or known that intergalactic space is different then outer galactic space, mainly outside the solar system is still in a ginormous gravity well of the galaxy. So there is a give or take edge to the galaxy, its gravitational extent. Like if we had a test mass/star and placed it at increasingly distant increments away from near the outer stars, at some point it would be out of the gravitational extent, I never suggested there was a pretty and clean edge like marble counter top, but more a massive cosmological edge, where gravity well meets incoming dark energy.

Think about that super massive black hole now heading in a linear direction through space, and the stars spiraling about it, and this occurring in and because of a gravity well. Is it possible the angular momentum of star rotations swinging around towards the front of the black holes path of momentum have some interaction with the ever newly created gravity well in front of the galaxies path, and this momentum meeting the oncoming dark energy could create some sort of extra gravity/energy barrier, which causes the stars instead of flinging off, to be compelled to swing around the other side. And then instead of swinging around the tail end and off into outer galactic space, the same thing occurs, the gravity well of the tail end always being dragged towards the linear path of the center of mass, while the dark energy seals up and creates a barrier, which compels the stars to swing around toward the front, and rinse and repeat.

I am not saying this idea is perfect, but I certainly feel there is something potentially to it. This is a very natural and organic view of the universe, because to be honest I dont know how exactly to think of fields, gravity fields, energy stress tensors, are these like fabrics, materials, substances, liquids... space is something mysterious and the nature of fields hidden, from my mind at least.

Some comments on the answers. More directed towards Eros or anyone else who knows any physics, but might be interesting to others, too...

dragonridr
What were the initial conditions that triggered the big bang?

ErosA433
OK deep breath, let me have a go at some of these from my understanding as a Particle Physicist and an experimental dark matter physicist.

Unknown, but scientists are looking and theorizing. But there are many theories out there as there are philosophies

Well, that's not quite true. We know it probably formed as some kind of bubble-nucleation like process. It's been well understood since the 70s or 80s how this kind of thing can happen. The difficulty here is what kind of bubble nucleation process . The detailed physics depends sensitively on the shape of the potential, which is hard to control from observations and experiment, and the theoretical guidance is limited at the moment.

But saying we don't know what caused it is a bit disingenuous. It's like saying you don't understand how bubbles nucleate in a glass of Coke because you don't know all of the dynamical details off the top of your head. That doesn't matter--the "what" and "how" are easy to understand. Detailed calculations, of course, aren't!

dragonridr
What caused the repulsive gravity of the inflation era to end?

ErosA433
Once again, somewhat of an unknown.

Well, again, not quite unknown. Fields are able to source terms which have effective components that look like cosmological constants, so it should not be too surprising that there was an inflationary period. The details of how this looks relate closely to the shape of the potential in the previous question.

dragonridr
Why Does Matter Exist? ( ill explain here there is no reason we shouldn't have had baryon asymmetry or simply why we had more matter then anti matter)

ErosA433
There is a very good reason why we expect there not to be a baryon asymmetry. All processes we have observed appear to follow to a very very good order (taking about to better than 99.9999999%) all matter created is created with an anti-matter, conserving energy and momentum. There are a few ways which are postulated to selectively remove anti-matter but these are unconfirmed and still theoretically cannot give the properties of the cosmos that we have observed so far.

The best hope is charge parity violation, which has been observed in the quark sector, and possibly in the lepton sector. This process has to be done before the first stars start to form.

Yeah, CP violation is a good one, and isn't known to be strong enough. But there's no reason to expect the amount of CP violation at low energies to reflect the amount at very high energy.

In fact, considering there's no reason to expect the Standard-Model-as-an-EFT Lagrangian to have terms which are all CP-preserving, the more interesting question is why we have so little apparent CP violation!

dragonridr
Why Do Fundamental Constants Have the Values They Do?

ErosA433
I think this is largely unknown, though it is amazing that the universe is governed by i think 6 constants/ratios, ie, the constants can change, though if the universe is to appear like we see it, those 6 ratios need to be the same/similar.

Why the constants have the values they do is sort of uninteresting. There had to be constants, and they had to have some value, so it's kind of like rolling some dice and asking why they had to come up the way they did.

The more interesting question is what the space of all reasonable theories looks like, and, as Eros mentions, how the constants can be parameterized and what the possible sets of parameters looks like (i.e., do we expect there to be few such constants or many, etc).

I'd argue that on general EFT-thinking grounds, you'd expect there to be "not too many" constants in some sense, just because you tend to not have too many low-energy fields and not too many low-energy terms in your low-energy EFT. So you shouldn't be too surprised by there being a smallish number of constants (even though I'd say the actual number of real independent Standard Model "constants" is much larger than a half-dozen or so, and closer to 100 or so).

dragonridr
What Is Dark Matter?

ErosA433
Unknown, though we strive to find out. [...]
So we propose several solutions, hot dark matter and cold dark matter.
[...]
What ever it is observations point at it being, a very weakly interacting particle, it might not even couple to our known particles at all, there is nothing theoretical that says it must... it would be a shame... but our hopes is on finding the easiest candidate for dark matter, the so called weakly interacting massive particle.

Well, it couples to gravity at least, which means it couples "somehow" to to the other forces, at least at very high energies. There are lots of possible particles that can do that. String Theory and other BSM theories provide lots of plausible candidates.

And I think it's important to emphasize that dark matter is almost definitely a particle of some kind or another (as opposed to a modification of other laws of physics, or something totally new).

dragonridr
Why does time only move in one direction?

ErosA433
I think this is more by definition of our experience and more of a philosophical question, i touched on it before in regard to anti-matter and CPT transforms, but since we do not see apparent "anti-matter people" we cannot really say or understand if time goes backwards for them.

This is actually totally well understood, and has been at least since the early 1800s, which is probably the first time anyone really thought about it seriously.

Generally, the reason is simply that conditional probabilities are not symmetric when you interchange their arguments: P(A|B) is not the same as P(B|A). This is clear even when applied to ordinary classical mechanics (and is why usually basic statistical mechanics describes things like entropy in terms of classical phase space, and then makes some "weird" assumptions that are equivalent to using that property).

A simpler way to think about it is that logical implications are one-directional. X => Y does not imply Y => X. Therefore the existence of any ordering of events implies a logical arrow of time, and any other arrow of time must agree with the logical arrow of time.

Great post and some excellent points and expansions.

The nucleation process, much like nucleate boiling is one such model which I was thinking about when I wrote the reply, though I didn't want to stamp it as being "the one" since it, like many things are a combination of speculation and are model dependant.

Though Id say it is indeed the best one out there. The boiling has been researched and understood, and it does occur with different stages depending upon initial conditions. The thing with nucleation is that it does often require some initiate.


On CP violation, your points are obviously quite true and valid, as the forces change at higher energy it is entirely possible that CP violation amplifies, in is quite probable what happens. again though before we can prove this kind of thing even at a tiny level at low energies it remains speculation of a model. It is also what is of great interest in the lepton sector which there has been evidence of an energy dependant oscillation with CP violation. (IE at different energies anti-neutrinos oscillate differently to neutrinos) All these things are being explored by neutrino physicists (was my PhD field, I was in T2K) and flavour physicists.

On dark matter I think i corrected myself to say it does only couple with gravity and you are correct that it is a good assumption that it does couple thus with all other fields, even if just at high energy. But thats the issue, if it only couples at high energy, then we are not guaranteed to see it in our detectors or even create it in colliders.