What exactly is all this Dark matter anyway?

What exactly is all this Dark matter anyway?

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Gene Vincent

Original Poster:

4,002 posts

159 months

Saturday 21st July 2012
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Another thread about the latest thinking on Dark Matter, there'll be another about Dark Energy... you have been warned.

I am on call for a few days so may have to drop this, so it may appear in parts over that time.

The first thing to say is that DM is likely the most misunderstood thing about this Cosmos, it shares this elusive property with Dark Energy, they are not the same thing and describe totally different phenomena, but as always they may in the finality of things be related closely in ways we as yet not observed.

We need to get clear a few things about what we do know, first there appears to be quite a lot of it and it possesses some intriguing properties, the first is that although it is 'matter' it appears to be stable without the interaction of the full integer spin particles Quantum Field, these particles give matter its 'solidity', this means that unlike all the matter we encounter, it is not solid and it would pass straight through us and our planet without anything of note happening, unless it was a dense field of it and then that would be very different.

This is why its discovery didn't really change the Big Bang theory, it changes a bit, but nothing of consequence.

The natural question to ask is, 'If it is so elusive how do we really know it is there?' the answer is startlingly simple, it interacts through gravity and that is how we know of its presence.

It is as if the full integer field non-interaction was being compensated for with some sort of Gravitational Field, this is very challenging... because we don't have an account for there being a Gravitational Field, just the attribute of Gravitation.

This causes huge difficulties for the maths.

Quantum maths predicts something that is not too dissimilar to Dark Energy, but not really Dark Matter.

Other odd things we do know with a reasonable degree of certainty is that DM doesn't decay, it appears immune to the action of the weak force and everything else in the Cosmos that depletes all normal matter.

I think it is about the right time to tell you something that might be hard to take, but despite all you have ever read, the fundamental particles are not actually made of anything, they are not something at all, so all those models of a Nucleus and then a huge gap and a tiny electron circling it are even more strange, because you are regularly told that most of an atom is empty space, the reality is that it is all empty space.

I know, I know... it's hard to take, but I have been building up to this in previous posts and if you've tagged along so far you'll just about be able to accommodate this fact.

The well read and the well cosmologically versed will retort that there are tests that prove that wrong, the original experiment that 'proved' that atoms were mostly empty space is well known to those that take an interest, but it isn't the first time, nor will it be the last that what we think we see is not what really is.

You see there are perhaps 13 fields in the Cosmos, 11 pretty well defined and a couple that we have a less than perfect grip of, and it is those fields that create a 'state' a cosmological condition that produces things like Fermions and all the rest...

Now for the hard bit to grasp, despite each field having the name of the particle and is the progenitor of that particle, it is quite rare for that actual particle to appear in that field, so although the Cosmos is filled with a quark field, every quark produced needs to interact to become detectable, notice I didn't use the words 'become something', because it really isn't fundamentally something at all.

It is this constant interaction that gives all we see around us its identity as something.

Dark matter doesn't do this, well at least not fully.

I'll let you digest this before proceeding, I think there might be a few questions raised by this...


Edited by Gene Vincent on Saturday 21st July 17:14

davepoth

29,395 posts

200 months

Saturday 21st July 2012
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"We don't know, but we're trying to find out" is about where we are.

CrabDan

568 posts

144 months

Saturday 21st July 2012
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I'm not even going to pretend to understand that...

Which I guess means I'm not a physicist hehe

Gene Vincent

Original Poster:

4,002 posts

159 months

Sunday 22nd July 2012
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Bedazzled said:
Another interesting post. Good stuff, although I'm a bit skeptical about such a literal interpretation of QFT, in terms of physical reality.

I think I can see what's being suggested though, if matter is just field perturbations, and DM doesn't interact with the electromagnetic field then it won't have any 'substance' because it won't repel other matter, and it will be invisible because it doesn't interact with photons; but it's still 'there' and interacting with gravity.

BUT... you could also interpret DM as a fudge to make existing theories fit with observation, nobody really knows what gravity is, apart from Einstein's theory about curved spacetime.

Looking forward to reading about dark energy...
You are right to be sceptical, but we are coming closer and closer to fully understanding that there really is no such thing as 'substance' at a quantum level and that only at the macro level we have things of substance and this has lead to some, me included, to consider that here-in lies the key to failure to compound both the Micro and Macro Cosmos.

It may be the path to a unified or unifying concept.

I can't detail anything of consequence here as I might be compromised, but by following this path there is, perhaps, a way to bring gravity in from the cold and truly understand it and define its core, but essentially gravity may just be the result of the cotermineity of the fields themselves, this works with Einsteins macro-view and does not interfere with the effect in the micro-view.

We are possibly looking at gravity making up the difference in the Dark Matter that is missing through a failure of interaction... it has deep ramifications if so.

Purposefully sketchy I'm afraid...

mattnunn

14,041 posts

162 months

Monday 23rd July 2012
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Porpusefully sketchy? Said one dolphin to another... I'm coming up for air, clear your blow hole.

Soren Kierkegaard and the existentialist movement through absurdism enlightened humanity to the concept of the nothingness of matter nearly 200 years ago, you saying it with maths is no more powerfull than them saying it with words. The truth is in human perceptions.

P.S In a conversation regarding the non existence of matter and all that this entails I'm suprised anything could be off topic, why not show your workings and let us judge your genius?

don4l

10,058 posts

177 months

Tuesday 24th July 2012
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Gene Vincent said:
This is why its discovery didn't really change the Big Bang theory, it changes a bit, but nothing of consequence.
I was unaware that dark matter had been discovered.

I thought that its existence was postulated - due to the fact that galaxies appear to be rotating faster than Einstein predicts.


Don
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The Nur

9,168 posts

186 months

Tuesday 24th July 2012
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As far as I can tell (and bear with me on this one) it is the "what is" to our "what isn't"

So what is here is the opposite of what is there. Wherever there is.

Gene Vincent

Original Poster:

4,002 posts

159 months

Tuesday 24th July 2012
quotequote all
don4l said:
Gene Vincent said:
This is why its discovery didn't really change the Big Bang theory, it changes a bit, but nothing of consequence.
I was unaware that dark matter had been discovered.

I thought that its existence was postulated - due to the fact that galaxies appear to be rotating faster than Einstein predicts.


Don
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In a previous post I mentioned that both DM and DE are simply placeholder names for a phenomena, the phenomena exists as far as DM is concerned, there is less certainty as far as DE regarding a cohesive effect.

Not just rotating, but moving apart also.

The point you make is valid, but perhaps history shines a clear light on this, mathematicians have worked ceaselessly on the ramifications of the Higgs Mechanism for nearly 50 years, but only a few weeks ago it was 'discovered' and acclaimed as such.

I live in this day, if I were to wait for the Physicists to get to where I am, I'd be dead before they got to where I am on this day.

We may wait another 10/20 years before a 5 sigma on DM and perhaps 20/30 years for DE.

They won't even get there unless the mathematicians point the way to how to 'discover' it, to their satisfaction, in the first instance.


Lost_BMW

12,955 posts

177 months

Tuesday 24th July 2012
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Gene Vincent said:
Another thread about the latest thinking on Dark Matter, there'll be another about Dark Energy... you have been warned.
Keep them coming!

Blackpuddin

16,632 posts

206 months

Tuesday 24th July 2012
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We started off as amoeba and turned into what we are now. Quite a big change over a relatively short timeframe. Amplify that evolutionary process a thousandfold across a billion civilisations and the result (surely?) has to be lifeforms based on non-corporeal energy. In other words, dark matter. Admittedly not a very technical theory but not that hard to get one's nut around.

don4l

10,058 posts

177 months

Tuesday 24th July 2012
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Bedazzled said:
A couple of interesting titbits...

Evidence of dark galaxies here

Galaxy without dark matter here

On galaxy rotation; it's interesting that visible matter forms into a galactic disc, due to its rotation and self-interaction (energy dissipation), whereas dark matter forms a sphere around our galaxy. On a smaller scale, solar systems also form as accretion discs, yet on an intermediate scale globular clusters are spherical rather than disc-shaped like mini-spiral galaxies... why is that?
The dark galaxies are nothing to do with dark matter. They are just clouds of hydrogen that lack the density/mass to form a proper galaxy.


NGC4736 is interesting. Does anyone know how they measure the rotation speed of a face on spiral galaxy?


Don
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AJI

5,180 posts

218 months

Tuesday 24th July 2012
quotequote all
Gene Vincent said:
I think it is about the right time to tell you something that might be hard to take, but despite all you have ever read, the fundamental particles are not actually made of anything, they are not something at all, so all those models of a Nucleus and then a huge gap and a tiny electron circling it are even more strange, because you are regularly told that most of an atom is empty space, the reality is that it is all empty space.

Edited by Gene Vincent on Saturday 21st July 17:14
I'm guessing you would have been expecting a question arising from the above quoted text... wink
When the likes of CERN collide particles and they are able to trace the resulting sub-particle paths, what are they actually tracing?
I know when I was there a number of weeks ago, the tour guide mentioned that they basically track the various energies (or forces produced within the detector fields), but I was taking this to be a method of tracking the particle itself. Is this not the case?

Gene Vincent

Original Poster:

4,002 posts

159 months

Tuesday 24th July 2012
quotequote all
AJI said:
Gene Vincent said:
I think it is about the right time to tell you something that might be hard to take, but despite all you have ever read, the fundamental particles are not actually made of anything, they are not something at all, so all those models of a Nucleus and then a huge gap and a tiny electron circling it are even more strange, because you are regularly told that most of an atom is empty space, the reality is that it is all empty space.

Edited by Gene Vincent on Saturday 21st July 17:14
I'm guessing you would have been expecting a question arising from the above quoted text... wink
When the likes of CERN collide particles and they are able to trace the resulting sub-particle paths, what are they actually tracing?
I know when I was there a number of weeks ago, the tour guide mentioned that they basically track the various energies (or forces produced within the detector fields), but I was taking this to be a method of tracking the particle itself. Is this not the case?
Yep.

They don't track the particle at all, they track decay paths.

AJI

5,180 posts

218 months

Tuesday 24th July 2012
quotequote all
Gene Vincent said:
AJI said:
Gene Vincent said:
I think it is about the right time to tell you something that might be hard to take, but despite all you have ever read, the fundamental particles are not actually made of anything, they are not something at all, so all those models of a Nucleus and then a huge gap and a tiny electron circling it are even more strange, because you are regularly told that most of an atom is empty space, the reality is that it is all empty space.

Edited by Gene Vincent on Saturday 21st July 17:14
I'm guessing you would have been expecting a question arising from the above quoted text... wink
When the likes of CERN collide particles and they are able to trace the resulting sub-particle paths, what are they actually tracing?
I know when I was there a number of weeks ago, the tour guide mentioned that they basically track the various energies (or forces produced within the detector fields), but I was taking this to be a method of tracking the particle itself. Is this not the case?
Yep.

They don't track the particle at all, they track decay paths.
So where would be the boundary at which 'science' would start to say there is 'something' there?
I know you referred to the micro and macro levels, but is there a precise region at which 'nothing' becomes 'something'?

Just to get my head around your descriptions above....
Would it be similarly described that on the single atomic level we observe individual 'packets' of energy (bound in to a specific region of space by the strong nuclear force and ?gravity? - thus defining a proton, neutron and electron (and the other sub-'particles')?
(I know there are other qualities that define sub-atomic 'particles' in order to distinguish each particle from another, but for the purposes of 'matter' alone would the above be a true analogy)?




edit to add : - re-reading my post it seems I am using the terms 'force', 'energy' etc. with a loose connection to the reality of what it going on. But hopefully you can 'follow' what I am trying to question.


Edited by AJI on Tuesday 24th July 14:37


Edited by AJI on Tuesday 24th July 14:38

mattnunn

14,041 posts

162 months

Tuesday 24th July 2012
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This is metaphysics.

How often am I told philosophy has no place in this forum?

And yet this is a metaphysical discussion.

Gene, and his ilk, are trying to reinvent academia in there own image.

They are the Stones to Plato's Chuck Berry.

AJI

5,180 posts

218 months

Tuesday 24th July 2012
quotequote all
mattnunn said:
This is metaphysics.

How often am I told philosophy has no place in this forum?

And yet this is a metaphysical discussion.

Gene, and his ilk, are trying to reinvent academia in there own image.

They are the Stones to Plato's Chuck Berry.
I don't realy have a problem with that to be honest.
To see things from other points of view can shed light on my own interpretation of what science observes.
As I am not a particle physisist and I don't have the means to question either peer reviewed or individual interpretation of science then I am open to other's perceptions on the subject.

In the end, however, I would always accept the peer reviewed material over individual hypotheses, but in this particular area of science I would hazzard a guess that as there is so much unknown involved then individual interpretation on observations holds a lot of merrit.

Gene Vincent

Original Poster:

4,002 posts

159 months

Tuesday 24th July 2012
quotequote all
AJI said:
So where would be the boundary at which 'science' would start to say there is 'something' there?
I know you referred to the micro and macro levels, but is there a precise region at which 'nothing' becomes 'something'?
I do like this site, it forces me to clarify my thinking by tracking my path to here... and that is a really good question, in fact so good that I will at some point expand upon what I'll write now in a separate thread.

We have to attempt to see things in perspective, there are many ways to do this and the net is full of wonderful animations about scale, but the one I use often to bring some insight is this:-

We all know how big 1 millimetre is don't we... and we can just about equate how big the known Cosmos is in relation to that 1 millimetre... well... within that 1 millimetre the phenomenon we are looking for is so small that it would be like putting 8 complete Cosmos' along that 1 millimetre and finding the in those 8 Cosmos' another microdecimally equivalent 1 millimetre... and the Real single Cosmos we live in is filled with phenomena that small. What is more, it is filled (perhaps) 13 times over!

In this scale of things it appears that the manner and number of field interactions dictate when 'something' has material existence, so it is difficult to say when 'matter' appears along the scale, this is made even more difficult when and because we look at it in detail.

Our very action of looking changes things, now this has been given some sort of 'WOOOO' or mystical slant by many.

That is totally wrong.

The real reason is that we can only observe by adding to the interactions of the fields. so by looking we compound the interactions and matter appears, it isn't magic, it is because by looking we interfere or add to the process, this only happens when we look at a tiny portion of the Cosmos, out here, as I tap my keyboard and it has solidity and presence the interactions were set long ago and are so long established that I could put my keyboard into a melting pot and make a mouse from it, without it disappearing out of existence and no longer being matter!

It's not a good answer but it is accurate as far as it goes, and I will address this fully in another thread at some point.



Edited by Gene Vincent on Tuesday 24th July 15:36

Gene Vincent

Original Poster:

4,002 posts

159 months

Tuesday 24th July 2012
quotequote all
mattnunn said:
This is metaphysics.

How often am I told philosophy has no place in this forum?

And yet this is a metaphysical discussion.

Gene, and his ilk, are trying to reinvent academia in there own image.

They are the Stones to Plato's Chuck Berry.
No, not at all.

This is not fanciful or mystical, matter exists due to interaction of the numerous fields, but when we look we add fields through observation and matter appears to just 'happen', that is due to Human interaction, the maths tells us differently to what we observe and that is part (but by no means all) of why we have a problem with this transition from the Micro to the Macro.

You'd have to be purposefully ignorant not to appreciate this fact and instead attribute a metaphysical or mystical meaning to it.

It is, in reality, the very antithesis of such.

IainT

10,040 posts

239 months

Tuesday 24th July 2012
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Gene Vincent said:
You'd have to be purposefully ignorant
Pretty good summation of his approach across these fora to scientific discussions.

Gene Vincent

Original Poster:

4,002 posts

159 months

Tuesday 24th July 2012
quotequote all
IainT said:
Gene Vincent said:
You'd have to be purposefully ignorant
Pretty good summation of his approach across these fora to scientific discussions.
Although mattnunn was quoted my post not aimed at him, it was aimed at the general point he raised, that there is a mystical element to field interaction causing things to become matter based on the fact that as soon as we look (use or add further fields) it just appears.

I wouldn't want mattnunn or anyone else feeling that they can't contribute to this sort of thread, I'd rather address the matter he raises and try to show where I believe he and his ilk are adding a further wrongful element or wilfully dismissing the 'core reale' for it.

He's not dumb, he has insight, it may not be the same on this, but intrinsically, he is another human being that I hope can persuaded to take a look from where I stand.