Everything's expanding... well no, actually.
Discussion
We read, see and hear that the Cosmos/Universe is expanding... well, only parts of it are actually.
Is this well known here?
In the light of how much some here didn't know/realise about 'time', before I proceed it would be good to know who understands why not all the Cosmos/Universe is getting bigger.
Over to you...
Is this well known here?
In the light of how much some here didn't know/realise about 'time', before I proceed it would be good to know who understands why not all the Cosmos/Universe is getting bigger.
Over to you...
Can I phone a friend?
Apologies, my first response was facetious. Yes, I understand the concept.
Perhaps rather than just stating something which most people hold to be "true" and then saying "aha! you're wrong!" you could post up a link to the research/article that is asserting that the universe is not expanding uniformly which we can then use as the basis for the discussion?
Apologies, my first response was facetious. Yes, I understand the concept.
Perhaps rather than just stating something which most people hold to be "true" and then saying "aha! you're wrong!" you could post up a link to the research/article that is asserting that the universe is not expanding uniformly which we can then use as the basis for the discussion?
Marf said:
Can I phone a friend?
Apologies, my first response was facetious. Yes, I understand the concept.
Perhaps rather than just stating something which most people hold to be "true" and then saying "aha! you're wrong!" you could post up a link to the research/article that is asserting that the universe is not expanding uniformly which we can then use as the basis for the discussion?
I did that with the 'Time' thread and it want 'all aghast' on me and thought this might be a better less assertive approach...Apologies, my first response was facetious. Yes, I understand the concept.
Perhaps rather than just stating something which most people hold to be "true" and then saying "aha! you're wrong!" you could post up a link to the research/article that is asserting that the universe is not expanding uniformly which we can then use as the basis for the discussion?
OK... New post coming up setting out how it is...
We will hardly pass a week by without being told that the Cosmos is expanding, we are often given analogies using balloons and all sorts of other minds-eye ways to envision this expansion.
Well the truth is that not all of the Cosmos is expanding at all.
In fact everything we can see... isn't.
Right out in that Deep Field picture from the Hubble Telescope every thing in that picture is not expanding.
Another fact about this expansion is that lots and lots of 'empty space' isn't either.
...and I'm not talking about Dark Matter or Dark Energy, we can forget them for the moment, they play no part in this explanation, we have to add and subtract them later, but first you need to know the basics and the basics are that the Cosmos overall is expanding, but all that I've outlined above isn't.
To save me writing something that is already well understood, do the majority understand that what I have written so far is correct and do you understand the 'mechanism' that causes this effect?
Well the truth is that not all of the Cosmos is expanding at all.
In fact everything we can see... isn't.
Right out in that Deep Field picture from the Hubble Telescope every thing in that picture is not expanding.
Another fact about this expansion is that lots and lots of 'empty space' isn't either.
...and I'm not talking about Dark Matter or Dark Energy, we can forget them for the moment, they play no part in this explanation, we have to add and subtract them later, but first you need to know the basics and the basics are that the Cosmos overall is expanding, but all that I've outlined above isn't.
To save me writing something that is already well understood, do the majority understand that what I have written so far is correct and do you understand the 'mechanism' that causes this effect?
d.My personal theory is that the regions of spacetime that aren't expanding are those occupied by particles of mass. Since no two particles of mass can occupy the same point in ST, the mass acts as a "hole" which in a sense displaces ST causing a local distortion that we perceive as gravitation. But for this idea to make any sense ST must be expanding (or trying/failing to expand in areas occupied by mass), and possibly expanding at an ever increasing rate (I haven't thought it through, not having the time, inclination or background).
Still, we can all have our ideas. Having read the "Time" thread, I expect to be branded an uneducated idiot, how I should read more about the subject and how much you enjoy reading posts from people who clearly have no clue about the subject.
Ok, over to you GV, tell it like it is and let the Education by Arrogance commence!
Still, we can all have our ideas. Having read the "Time" thread, I expect to be branded an uneducated idiot, how I should read more about the subject and how much you enjoy reading posts from people who clearly have no clue about the subject.
Ok, over to you GV, tell it like it is and let the Education by Arrogance commence!
Edited by FarmyardPants on Wednesday 22 August 14:53
Gene Vincent said:
To save me writing something that is already well understood, do the majority understand that what I have written so far is correct and do you understand the 'mechanism' that causes this effect?
I dont think its very well understood at all, otherwise you wouldnt go your week without being told about the universe expanding.I don't really understand what you mean when you say everything we see is not expanding? Red-shift, is it all a lie!?
I really really should enjoy these threads (Cambridge maths degree and keen interest in physics) but they aren't half hard work due to the general tone of the posts. If I wanted someone to stand up and say "I'm going to tell you all about this..." I'd attend a lecture.
I think the threads work much better when someone posts a link to something and it is then discussed.
I think the threads work much better when someone posts a link to something and it is then discussed.
FarmyardPants said:
My personal theory is that the regions of spacetime that aren't expanding are those occupied by particles of mass. Since no two particles of mass can occupy the same point in ST, the mass acts as a "hole" which in a sense displaces ST causing a local distortion that we perceive as gravitation. But for this idea to make any sense ST must be expanding (or trying/failing to expand in areas occupied by mass), and possibly expanding at an ever increasing rate (I haven't thought it through, not having the time, inclination or background).
Still, we can all have our ideas. Having read the "Time" thread, I expect to be branded an uneducated idiot, how I should read more about the subject and how much you enjoy reading posts from people who clearly have no clue about the subject.
Ok, over to you GV, tell it like it is and let the Education by Arrogance commence!
First, not knowing and wanting to know does not mean you are an uneducated idiot, in fact it is the exact opposite and I applaud all such noble intentions, I only decry those that know a bit but refuse to learn more.Still, we can all have our ideas. Having read the "Time" thread, I expect to be branded an uneducated idiot, how I should read more about the subject and how much you enjoy reading posts from people who clearly have no clue about the subject.
Ok, over to you GV, tell it like it is and let the Education by Arrogance commence!
Edited by FarmyardPants on Wednesday 22 August 14:53
So, your approach has nothing but respect from me.
It's a subtle difference but easily missed.
You are surprisingly close to being right, indeed no mass is expanding in this Cosmos at all and the reason is startlingly simple, it is Gravity.
Most people will know that mass concentrates gravity at its centre and the greater the mass the greater the gravitation that permeates from it and it is these gravity wells and all contained within them that does not expand, there is an 'event horizon' surrounding every Galaxy in the Cosmos, that event horizon is correctly called a Gravitational Extent Boundary and is the point where gravity and Cosmological expansion are equal... the extent of some Galaxies GEB is enormous.
So it is not the items in space that are expanding, it is the space between their GEBs.
A Black Hole Stars event horizon is huge compared to the size of the star within and the Black Hole Stars GEB is even larger by a substantial magnitude.
The expansion of the Cosmos 'pushes and pulls' these large GEBs along with it and because they are an area of stability within the motion we call the effect a phase shift or more commonly Red or Blue Shift. Red Shift is something moving away, Blue is approaching.
If you view this in your minds eye very carefully you see why we see almost exclusively Red Shift and not a lot of Blue.
Locally (in Cosmological terms) our own Galaxy is being approached by the Andromeda Galaxy, we see a blue shift in its signature.
Japsteeze said:
I dont think its very well understood at all, otherwise you wouldnt go your week without being told about the universe expanding.
I don't really understand what you mean when you say everything we see is not expanding? Red-shift, is it all a lie!?
Read my previous post and it all makes sense.I don't really understand what you mean when you say everything we see is not expanding? Red-shift, is it all a lie!?
It is very well understood, exactly in fact.
Ah I see what you were saying. I understand that objects are moving further apart, and it is not that everything is expanding. I was thinking that at the very start you were saying that galaxies etc are not moving futher apart, and disputing Hubble's law.
To think about heterogeneous expansion of space with gravity cancelling it in areas of significant enough mass, I imagine a ballon expanding (space) with taped sections of it (mass) holding that section together while the rest of space (baloon) expands.
To think about heterogeneous expansion of space with gravity cancelling it in areas of significant enough mass, I imagine a ballon expanding (space) with taped sections of it (mass) holding that section together while the rest of space (baloon) expands.
Japsteeze said:
Ah I see what you were saying. I understand that objects are moving further apart, and it is not that everything is expanding. I was thinking that at the very start you were saying that galaxies etc are not moving futher apart, and disputing Hubble's law.
To think about heterogeneous expansion of space with gravity cancelling it in areas of significant enough mass, I imagine a ballon expanding (space) with taped sections of it (mass) holding that section together while the rest of space (baloon) expands.
That is it. you have the correct image, bits of space remain 'glued together', that 'glue' is gravity.To think about heterogeneous expansion of space with gravity cancelling it in areas of significant enough mass, I imagine a ballon expanding (space) with taped sections of it (mass) holding that section together while the rest of space (baloon) expands.
The balloon analogy is misleading though as it expands due to increased matter entering a defined shape. The universe itself is expanding, and is actually more like the balloons skin expressed holographically, as it stretches (but without increasing in mass/energy) and is connected on all sides, i.e. without a boundary for you to reach.
So the gravity wells here would be like round stickers on the balloon's surface that stop that area of rubber stretching.
Great thread Gene, lecture away!
So the gravity wells here would be like round stickers on the balloon's surface that stop that area of rubber stretching.
Great thread Gene, lecture away!
Edited by MiseryStreak on Wednesday 22 August 16:25
Gene Vincent said:
FarmyardPants said:
My personal theory is that the regions of spacetime that aren't expanding are those occupied by particles of mass. Since no two particles of mass can occupy the same point in ST, the mass acts as a "hole" which in a sense displaces ST causing a local distortion that we perceive as gravitation. But for this idea to make any sense ST must be expanding (or trying/failing to expand in areas occupied by mass), and possibly expanding at an ever increasing rate (I haven't thought it through, not having the time, inclination or background).
Still, we can all have our ideas. Having read the "Time" thread, I expect to be branded an uneducated idiot, how I should read more about the subject and how much you enjoy reading posts from people who clearly have no clue about the subject.
Ok, over to you GV, tell it like it is and let the Education by Arrogance commence!
First, not knowing and wanting to know does not mean you are an uneducated idiot, in fact it is the exact opposite and I applaud all such noble intentions, I only decry those that know a bit but refuse to learn more.Still, we can all have our ideas. Having read the "Time" thread, I expect to be branded an uneducated idiot, how I should read more about the subject and how much you enjoy reading posts from people who clearly have no clue about the subject.
Ok, over to you GV, tell it like it is and let the Education by Arrogance commence!
Edited by FarmyardPants on Wednesday 22 August 14:53
So, your approach has nothing but respect from me.
It's a subtle difference but easily missed.
You are surprisingly close to being right, indeed no mass is expanding in this Cosmos at all and the reason is startlingly simple, it is Gravity.
Most people will know that mass concentrates gravity at its centre and the greater the mass the greater the gravitation that permeates from it and it is these gravity wells and all contained within them that does not expand, there is an 'event horizon' surrounding every Galaxy in the Cosmos, that event horizon is correctly called a Gravitational Extent Boundary and is the point where gravity and Cosmological expansion are equal... the extent of some Galaxies GEB is enormous.
So it is not the items in space that are expanding, it is the space between their GEBs.
A Black Hole Stars event horizon is huge compared to the size of the star within and the Black Hole Stars GEB is even larger by a substantial magnitude.
The expansion of the Cosmos 'pushes and pulls' these large GEBs along with it and because they are an area of stability within the motion we call the effect a phase shift or more commonly Red or Blue Shift. Red Shift is something moving away, Blue is approaching.
If you view this in your minds eye very carefully you see why we see almost exclusively Red Shift and not a lot of Blue.
Locally (in Cosmological terms) our own Galaxy is being approached by the Andromeda Galaxy, we see a blue shift in its signature.
GR gives a good explanation of the effects of gravity but I have yet to read a convincing theory as to the cause of it, probably because accepted theory is that it is a fundamental force (as evidenced by the fact that scientists often ask why it is so weak compared with the other forces) and as such it is not considered to be 'caused' by anything. I like to think that gravity is a side effect of something else, which is why I look this from the other perspective.
Gene Vincent said:
A Black Hole Stars event horizon is huge compared to the size of the star within and the Black Hole Stars GEB is even larger by a substantial magnitude.
As an aside, is the size of an event horizon as seen by an observer not a function of how far away the observer is from said BH? I guess no such thing applies to the GEB.Edited by FarmyardPants on Wednesday 22 August 17:06
FarmyardPants said:
GR gives a good explanation of the effects of gravity but I have yet to read a convincing theory as to the cause of it, probably because accepted theory is that it is a fundamental force (as evidenced by the fact that scientists often ask why it is so weak compared with the other forces) and as such it is not considered to be 'caused' by anything. I like to think that gravity is a side effect of something else, which is why I look this from the other perspective.
As an aside, is the size of an event horizon as seen by an observer not a function of how far away the observer is from said BH? I guess no such thing applies to the GEB.
The 'hashed' explanation is that gravity is an effect of the four-momenta.As an aside, is the size of an event horizon as seen by an observer not a function of how far away the observer is from said BH? I guess no such thing applies to the GEB.
It does work... up to a point but it is not a fulsome explanation yet.
The idea that gravity is a fundamental force is losing ground to a QFT based explanation..
A 'side-effect' is a very good place to hold your thinking as it is more likely that it is.
I'll run another thread on Event Horizons and some of the least realised aspects of what they really show about the fundamental aspects of Gravity.
It will be a long one though as I'll have to cover the (now dwindling) alternatives.
BenM77 said:
Interesting thread, so is it still believed that our galaxy is moving away from the big bang ?
We might be.But that local Andromeda blue-shift could mean that we are either in stasis or moving toward it and this might mean we have 'countered' our own 'personal' expansion from the BB.
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