Long Post on Relativity, seeking answers from the educated.

Be gentle with me please guys/girls. I’ve been a closet lover of relativity, quantum mechanics, and theoretical physics since I was 16 but don’t have much experience or knowledge other then what I’ve read in the library or discover/scientific american. I’d like to put a few concepts that I’ve always wondered and would hope those of you more educated then myself could explain a few things and maybe dispel some theories I’m partially convinced are at least in the ball park(in my mind).



Astronomical Distances



We measure the distances of our neighboring galaxies by their respective Doppler shifts, all of them are in the red so the general consensus is that the universe is expanding. I have a very hard time believing that not a single galaxy is moving closer to ours. That doesn’t mean I think that a galaxy should be coming directly at us, but assuming there is a center to the universe then you would think some of the galaxies with a similar distance from the center as ours could be moving in the same path around it as we are and accelerate just a hair faster then us(which would put said galaxy in the blue shift rather then red). The easiest answer would be that there is no center of the universe with gravity significant enough to control all the respective galaxies so we will just continue to leave each other until there wont be a single galaxy in sight.



My questions would be, is it possible that the black holes at the center of these galaxies stretch the light coming from them enough to justify their red shifts? Could cluster galaxies just be younger spiral galaxies that don’t have a strong enough black hole in the center to start pulling the outer stars in yet(weaker black hole=weaker red shift)? Would our view of quasars be somewhat flawed?(more on this). Some of these questions could be answered simply, but my googling efforts and library sifting have come up dry. Does light from the center of our galaxy shift to the red in the Doppler? I’ve tried to find if it does, and if I had the equipment/spectrometer and knew how to use it I’d make the observations myself. Its hard to think someone hasn’t already so I’m all but positive I’m wrong. Still want to see it though, the only light that this would apply to is the stars directly between the center of our galaxy and us, preferably the ones as close to the core as possible. If these stars did in fact get a significant shift from the black hole at its center then would it be smart to assume the center of our own galaxy is moving away from us?



Quasars get their own paragraph because they fascinated me and pretty much sparked my curiousity regarding the Doppler Effect and how we measure astronomical distances. Most experts agree that quasars are grandfather galaxies that have consumed the bulk of their celestial bodies. The mass accumulated by these monsters is so great that its believed many of the remaining stars have to orbit the center at speeds well over half of the speed of light. Since the black holes are so ridiculously massive could it not be assumed that their not moving away near the speed of light but are actually making the light work that much harder to leave the gravitational influence of the black hole that its topping out the Doppler Effect? You may point out that if that were the case then all galaxies should shift that far in the red since their TOTAL mass is the same as a similar quasar of the same total mass…just not packed into a black hole. I disagree, and I’ll explain under my gravity inquiry.


Before hammering me I beg to read the next 2 installments below. Just so you can really let me have it.




[edit on 1-6-2006 by MarkDravs]

Gravity





If you were to make a top 10 list of sciences greatest mysteries very few could resist putting gravity at or near the top of said list. My questions and concepts concerning gravity go a lot further then just a force that holds solar systems and galaxies together. A force so powerful cant be invisible, it just cannot…period. One force to rule them all, I like to think of it. No one can argue gravity as being the strongest of all forces(black hole) being able to collapse the entire atom…spitting in the face of the strong/weak/nuclear forces. So I’ve thought about it for years, and maybe 3-4 years ago I was thinking about a relativity book I read(it was very old but touched base on everything concerning general relativity) there was a particular section of the book that spoke very briefly of a universal liquid or “ether” as it put it.



The idea of any kind of universal liquid with near no viscosity at all has been dismissed by experts as far as I can tell. Many scientists have made predictions of the nature of such an ether and failed miserably in their experiments to prove it. Michelson and Morley(early 1900’s I think?) did some experiments trying to detect “ether winds” that they predicted would occur in their construct of this liquid and failed to produce them; however they did discover that accelerating particles to great speeds increased their lifespan significantly.



At this point your probably wondering what I’m babbling about when the topic is gravity, I’m getting there I promise. Now, we got a few occurrences that need explaining.



1. Objects naturally are attracted to more massive objects in the universe(gravity) some objects are so massive that even light cannot move away from them.
2. Only waves in the electromagnetic spectrum can travel the speed of light. If object with mass attempts to accelerate to the speed of light…the faster it go’s the more resistance it experiences.
3. Particles accelerated to great speeds and recieving this resistance(50%+ the speed of light) have significantly longer lives.


These three things are very difficult to grasp for me if space is in fact a vacuum. HOW could an object actually INCREASE in mass as it accelerates if there was nothing there to cause this resistance. Example to digest…



Your in a pool with a screen window, and drop the window into the water and pull it towards you very slowly. It is very easy, now pull the screen window through the water very quickly…the harder and faster you pull…the HEAVIER it feels. Now this may be a shotty representation of space/time and the makeup of our universe but it’s a start. The same logic can be applied to atoms feeling this same resistance…increasing speed and feeling the strain of such a resistance could bog down everything on the molecular and atomic levels. Twin Paradox anyone? So those two things tie together, and set up the harder thing for me to comprehend or create my own fantasy construct for, Gravity!

one more, bear with me, and i apologize for all the mispellings of relativity.

[edit on 1-6-2006 by MarkDravs]

There isn’t an easy way for me to communicate what I see in my mind as the foundation our universe has to facilitate this monster force, I will do my best though. The reason you cant really view any type of ether as a literal liquid like water or a type of hydraulic fluid is because it doesn’t just act as the “governor” for our universal speed limit or the guide in the flow of time in space. It also has to be the facilitator of the force that makes the universe go round…literally. When I think of the nature of gravity, I think the best way of putting so you can build the 4 dimensional picture in your head rather then the general funnel “free fall” picture you’ll find in most relativety books, would be to give this liquid the benefit of the doubt and assume it has a unique attraction to matter(pure matter at the atomic level) A baseball is made of matter yes...but only the pure energy inside it actually interacts with this ether.


The only thing that this liquid does not flow through is that pure energy, or the actual matter inside the atom. We all know that we’re 99.9% empty space or something like that, so we pretty much are just big screen doors. The .1 % or however small percent of us IS actually “rock hard” energy, compact energy that can separate this liquid…matter and only matter can separate it. All the pure energy particles in the sun are in fact punching holes in this ether; creating spaces in it. That would be the one single significant physical effect I could see matter having on the ether. The trick is picturing how such an effect causes the surrounding ether to stretch towards the holes creating an area of influence around it that smaller objects fall into. One understanding of gravity that I think can be considered fact is that the more MASS you have the stronger the field, and the smaller the space this mass is packed into creates a STRONGER sphere of gravitational influence. I did not say it makes a LARGER sphere of influence i said it makes a STRONGER one. Meaning that a golf ball weighing 20 lbs and a basketball weighing 20 lbs would share the same sphere of influence, maybe the basketballs being somewhat LARGER. However the basketballs gravitational field would be significantly weaker due to the concentration of matter in the golf ball one. Not only is there alot more space between where the border of the basketball would start and the border of the golf ball stars that would show a significant increase in field strength as you grew closer, but also the overall field itself would be stronger throughout the area around the object. I'll explain why if you want.



I’ll quit there for some feedback and flaming. I totally expect to be a somewhat belittled due to my lack of experience and knowledge. Just keep in mind they are just ideas, and i’d hope to find out the flaws in my thinking. The chance to debate any disagreements is always a plus to. Hope it was worth the few minutes it took to read anyway.

Originally posted by MarkDravs...I have a very hard time believing that not a single galaxy is moving closer to ours.

Don't blame you. I'd have a hard time too, if anyone were actually saying this.

the fact is, some are moving towards us. In fact, we're due for a collision with one in Pegasus (I believe it is) in the distant future. But don't worry, it won't happen until well after our Sun has expanded out to Earth's orbit as a red giant, and subsequently fried us all. So the destruction of our galaxy in this collisioon won't affect me and you, nor our gene pools.

Originally posted by MarkDravsThat doesn’t mean I think that a galaxy should be coming directly at us, but assuming there is a center to the universe then you would think some of the galaxies with a similar distance from the center as ours could be moving in the same path around it as we are and accelerate just a hair faster then us(which would put said galaxy in the blue shift rather then red)...

If relativity is correct, then there is no center of the universe. That is not speculation, it is only an assumption that relativity is correct.

Harte

Originally posted by Harte

Don't blame you. I'd have a hard time too, if anyone were actually saying this.

the fact is, some are moving towards us. In fact, we're due for a collision with one in Pegasus (I believe it is) in the distant future. But don't worry, it won't happen until well after our Sun has expanded out to Earth's orbit as a red giant, and subsequently fried us all. So the destruction of our galaxy in this collisioon won't affect me and you, nor our gene pools.



If relativity is correct, then there is no center of the universe. That is not speculation, it is only an assumption that relativity is correct.

Harte

Which galaxy is coming towards us? That would be a very interesting read for me and naturally help answer my question referring to gravity and the doppler affect depending on how far into the blue shift it is. Also I wonder if I could get a reference to another good read on relativity and that assumption of the universe having no center. With the expanding nature of the universe we percieve then its an easy assumption to make, I just had thought most Big Bangers and expanding/collapse pushers had a universal center to which the universe surrounds, and that relativity is their basis for the basic understanding of what makes the universe tick.

Originally posted by MarkDravs
Which galaxy is coming towards us? That would be a very interesting read for me and naturally help answer my question referring to gravity and the doppler affect depending on how far into the blue shift it is.

Read This:
Our Impending Collision with the Andromeda Galaxy

I found this HERE
Variations on the search terms in that search might yeild way more info.

Originally posted by MarkDravsAlso I wonder if I could get a reference to another good read on relativity and that assumption of the universe having no center.

I'd recommend "The Evolution of Physics" by Albert Einstein. Still in print last I checked. A good read.

Regarding the center of the universe, this is easy if you know any relativity at all.

Relativity basically just says that no reference frame is better than any other. This means that there is no observer's observations that are more authoritative than those made by some other observer. That's why the term "relative" is used. As an example, you'd think that a light beam viewed from a spaceship that was going near lightspeed would look slower (if it was going in the same direction as the spaceship) than that same beam veiwed by some guy back on a planet watching it go by. Turns out both observers measure exactly the same speed for the light beam.

The Michelson Morely experiment established that there was no "ether" against which to measure the velocity of light. Einstein developed this idea further into the concept of there being absolutely no reference frame that was "at rest" relative to all other reference frames, for if there was one, an observer in that "at rest" reference frame could make observations that had greater authority that an observer in a moving reference frame. Do you see why?

But the non-existence of the "at rest" reference frame would be negated if there were a "center of the universe." That's because the center would be an "at rest" reference frame!

Originally posted by MarkDravsWith the expanding nature of the universe we percieve then its an easy assumption to make, I just had thought most Big Bangers and expanding/collapse pushers had a universal center to which the universe surrounds, and that relativity is their basis for the basic understanding of what makes the universe tick.

The weird and scary truth of the matter is that the expansion of the universe that began with the Big Bang entails the expansion of the very fabric of space itself, not the spreading out of the materials that are found within that space. The "dots on a balloon" analogy makes this clear. It also demonstrates the lack of a need for a center of the universe. It is perfectly possible for all galaxies to be moving away from each other (with local exceptions for galaxies that are attracted by a nearby galaxy's gravity) without there being some "center" away from which they all must be moving. Remember the dots on the balloon surface represent the galaxies, the increasing surface area of the balloon is our expanding universe. Every dot is receding from every other dot, yet there is no center on the surface of the balloon away from which these dots are receding.

Harte

Originally posted by Harte

Read This:
Our Impending Collision with the Andromeda Galaxy

I found this HERE
Variations on the search terms in that search might yeild way more info.

I'd recommend "The Evolution of Physics" by Albert Einstein. Still in print last I checked. A good read.

Thank you for the reads, the first link is interesting. Obviously it must have been a fun experiment to get their hands on that much computing power to simulate such a massive collision. Although it doesnt really give me anything as to why they suspect the collision. The gravity of our galaxy and its nearest neighbor should logically attract them to each other, but I was hoping for the reason why they suspect this collision other then that assumption our gravities attract(observations) Thanks i'll definately pick up the book, the relativity books that i've read have all been written by authors commentating einsteins work in GR and SR, I didnt even know that book existed. I just assumed his published works were mainly GR and SR, with his twilight pursuit of a GUT producing a few other good reads.

Originally posted by Harte
Regarding the center of the universe, this is easy if you know any relativity at all.

Relativity basically just says that no reference frame is better than any other. This means that there is no observer's observations that are more authoritative than those made by some other observer. That's why the term "relative" is used. As an example, you'd think that a light beam viewed from a spaceship that was going near lightspeed would look slower (if it was going in the same direction as the spaceship) than that same beam veiwed by some guy back on a planet watching it go by. Turns out both observers measure exactly the same speed for the light beam.

The Michelson Morely experiment established that there was no "ether" against which to measure the velocity of light. Einstein developed this idea further into the concept of there being absolutely no reference frame that was "at rest" relative to all other reference frames, for if there was one, an observer in that "at rest" reference frame could make observations that had greater authority that an observer in a moving reference frame. Do you see why?

I'm familiar with the speed of lights constant no matter which relative frame of reference it is viewed from; however i disagree with a few notions to the "at rest" frame that you refer to. In the expanding balloon example or watermelon example described to paint a picture of an expanding universe, there is in fact an at rest frame of reference, space is 4 dimensional. All of the expanding galaxies are not only expanding from each other, but expanding for a center focal point. If there were a big bang that initiated this process. The balloon would have started out very small, and expanded around the "ground zero". I'm not saying thats the way of it, but to say there can be no relative center sounds foolish. It would be like saying there is no center to our galaxy to which all our stars revolve around. How can we make such a bold statement? For all we know our galaxies make up another larger cosmic system that has many brothers and sisters similiar it. Thats going a little too far into ridiculous science fiction at this point, but to say there can be no center of our universe simply because there can be no relative center is ridiculous. I really didnt get from the michelson morley experiment how it disproved the notion of an ether, I'd rather take it as an elimination of some assumptions they made to its nature as a universal atmosphere.

By the way i appreciate the discussion, its a subject I'm extremely interested in and have very little luck finding someone willing to circle the wagons so to speak on the issue.

I hope my questions arent annoying, or naive to you.

Yeah, Harte's right on a lot of things there - I like him for that. As for the center of the universe bit, well...

If we consider Relativity to be true (which you said you were a fan of, I am too), then there will be no center to the universe.

Why? Because General Relativity is about a warpage of space-time, which is to say the warpage of 3-dimensional space through the 4th dimension. To put it bluntly, the reason you stay on the earth is because it's the closest distance between now and then (that's the most blunt answer).

Now, if this 4th dimension exists, which it must if we're considering relativity to be true, then there's 2 possible main shapes for the universe to take.

The first is a closed system, a sort of 4-dimensional sphere... which is impossible to comprehend. The closest you can come is a 4-d cube, a Tesseract (research it, it's fun!). In this universe, if you travel in a straight line as far as you can, you will eventually reach the point where you started (either in space or in time or both :s - it's unknown). Consider it as such. If you were 2-dimensional, you would have absolutely no concept of up or down - you couldn't even imagine its existance. However, if you lived on the surface of a 3-d basketball, the you could travel around and around without finding an edge to the universe, and you would eventually find the spot where you started from.

That's what scientists today think is happening. It's a very cool concept. If you change the basketball to an expanding balloon, then you also start to grasp how space-time expands as the universe expands, because the surface area grows as the volume increases.

Now, the other theory is that this 4-d universe is "open" which means that it doesn't curse back in upon itself, and actually extends for infinite in all directions. The most common referral is a "saddle-shaped" universe, which is confined and constrained in the middle, but stretches towards unbelievable asymptops at the edges - which constantly are expanding away from us.

In short, it's confusing, but we're pretty positive that one of these two events are "what is".

Originally posted by MarkDravs
Thank you for the reads, the first link is interesting. Obviously it must have been a fun experiment to get their hands on that much computing power to simulate such a massive collision. Although it doesnt really give me anything as to why they suspect the collision.
...I was hoping for the reason why they suspect this collision other then that assumption our gravities attract(observations).

The impending collision is predicted because of exactly what you said in an earlier post, the light from Andromeda as we percieve it is blue-shifted.

Originally posted by MarkDravsThanks i'll definately pick up the book, the relativity books that i've read have all been written by authors commentating einsteins work in GR and SR, I didnt even know that book existed.

Einstein had a co-author on that book - can't remember his name.
The first half of the book provides a general overview of classical physics. IOW, mechanics and then electricity and magnetism. Sort of a refresher to make sure everyone's on the same page when they start in on the relativity.

Originally posted by MarkDravsI'm familiar with the speed of lights constant no matter which relative frame of reference it is viewed from; however i disagree with a few notions to the "at rest" frame that you refer to. In the expanding balloon example or watermelon example described to paint a picture of an expanding universe, there is in fact an at rest frame of reference, space is 4 dimensional. All of the expanding galaxies are not only expanding from each other, but expanding for a center focal point. If there were a big bang that initiated this process. The balloon would have started out very small, and expanded around the "ground zero".

Don't squeeze the analogy! Remember, the universe in the example exists only on the surface of the balloon, not in the center. Your determination to assert a center of the universe has now placed you in five dimensions. Our 4-D spacetime continuum has no center in the 4-D continuum we live in. Similarly, your balloon center causes you to step outside the 2-D "balloon universe" that exists on the balloon's surface.
If you stepped into 5-D, what would you do if you saw that, yes our universe has a center, but after looking around you realized you were looking at an infinity of other universes, all rushing away from each other and away from ours, and with no apparent center there in your new 5-D universe?

Originally posted by MarkDravsI'm not saying thats the way of it, but to say there can be no relative center sounds foolish. It would be like saying there is no center to our galaxy to which all our stars revolve around. How can we make such a bold statement?

It certainly is bold, and yes it sounds foolish. Remember what Albert said, "The universe is not only stranger than we imagine, it's stranger than we can imagine."

Originally posted by MarkDravs...but to say there can be no center of our universe simply because there can be no relative center is ridiculous. I really didnt get from the michelson morley experiment how it disproved the notion of an ether, I'd rather take it as an elimination of some assumptions they made to its nature as a universal atmosphere.

It does seem ridiculous, but if there is a center, then relativity is wrong. You might want to start figuring out new ways to test relativity, because it's passed all the tests up to now with flying colors. And remember, even if one day some errors are found in the theory, the concept in relativity which rules out the universal center - that of the equality of reference frames - would still likely remain a solid foundation for the next great cosmological theory. The results of having the "equality of reference frames" idea have been observed too accurately for too long for me to easily accept that the idea itself is completely wrong, no matter how "foolish" the logical conclusion to the idea may get.
Here's a link to a page about Michelson Morely:
www.phys.unsw.edu.au...&M.htm

It was in my "favorites" file from some time back, but I didn't go there to check it. Hope it's still active. If not, you can find out about it through Google. If you look, you'll find that Michelson Morely blew the "ether" away. The "ether" that is, that was supposed to be the medium through which electromagnetic waves propagate. Of course, anyone can postulate the existence of some kind of "ether" which is undetectable. But if it's undetectable, it might as well not be there since it can have no observable effect, right?

Harte