Things Scientists Believe I Can't Accept

Dark Matter: This is a bit long but I did my best to condense it.

First off I have no idea where you got the idea that Astronomers somehow "want" dark matter. Who told you this? Generally speaking scientists are the most conservative creatures on the face of the Earth. Some may be seen as iconoclastic as it comes to politics or social issues, but when it comes to science they are as conservative as it gets. There are two good reasons for this: they know their stuff backwards and forwards and they like knowing stuff, and the stuff works, so why would they want it to change? The second reason is it is very difficult and takes a lot of time and effort to learn an entirely new paradigm. They would rather spend their time working on new problems that can be answered with what they know than taking the time to learn the new stuff so they can work on these new problems. One of the reasons so many theorists resisted the string theories (besides that the theories are nuts) is because it was formulated in math that they didn't know and was very different from what they were used to, in addition to it being very difficult mathematics to learn. It is said that a theoretician wanting to move into string theory could look forward to several YEARS of intense study of these fields of math before they would even be able to have enough knowledge to be able to determine if the theory was worth working on!

So consequently, no one said: Oh boy! Lets postulate dark mater, won't that be fun!
The story in brief goes like this. By the 1970s it was clear that large clusters of mass in the universe: globular clusters, galaxies, clusters of galaxies should be flying apart over relatively short (astronomically speaking) time frames. They tried EVERYTHING that they could think of to see if they could find a way to explain these observations with standard (Newtonian/Einstein's) mechanics. They simply couldn't. Yet they were very sure the mechanics they knew was correct. They had to postulate other possibilities, eventually dark matter was postulated. That is how it happened.

My question to you is, why is the idea of something that only couples to gravity so outer that you can't deal with it? Colored gluons (the mediators of the strong force) don't couple to electrons but the world hasn't come to an end.

You'll have to excuse me but I got a TREMENDOUS laugh out of your question of why they just didn't change the formalism of mechanics to explain things. It is CLEAR you have no idea how ridiculous that sounds. Its nothing on you personally it's just that you are not knowledgeable in this area. So it is easy to understand that this would look like the path of least resistence. Nothing could be further from the truth. The physics of Newton and Einstein has been so formalized and detailed and has been tested so thoroughly that "simply" changing them is not something you just go out and do over a long weekend. A long couple of lifetimes, maybe. These theories are so tight that nearly any tinkering will cause internal inconsistencies that would not only not give you the answer to the new problem. They would not even be left in a form that could give you correct answers to things you already know. They would become useless.

By an analogy that I think gives the flavor of what you are saying: It would be like asking in today's world energy situation, "instead of conservation, or building new refineries, or finding new sources of energy why doesn't someone simply create an internal combustion engine that gets 100,000 miles to the gallon? Sure, piece of cake, we'll get right on that

I can give you a real example from the 1970s. As you may know, pulsars were discovered in 1967 by a grad student named Jocelyn Bell, now Jocelyn Bell Burnell, working for Antony Hewish.

(An interesting aside is that because of the type of signal they found it was believed that there was some possibility that these could be signals from an extraterrestrial civilization and so the first two sources were given original designations of LGM1 and LGM2. The "LGM" designation standing for: Little Green Men. Their true nature was soon discovered.)

It was known by observation that all pulsars known at that time slowed down as they spin. This was in perfect accord with mechanics. You could even get a good idea of how long a pulsar had existed by the rate it was currently spinning and how much it slowed down over time as it was observed.

Then suddenly a millisecond pulsar was discovered. Using the current theory and observations of its rate of slowing, it could be calculated that the pulsar was 4 to 5 times older than the universe itself. A few nutty ideas were put forward, such as the universe oscillated and that somehow this star survived several of these birth and death oscillations of the universe. This was, of course, the idea that the mass media latched onto. Scientists of course did not. Now they could have, or they could have said: "well I guess everything we know is wrong, no matter how many correct predictions our theories make, so let's throw it all out and just start over." Instead they said lets look a little deeper about what we know about these new types of objects (pulsars) and see if we can't figure out how this can be happening in a way that is reasonable and that doesn't require us to throw out a perfectly good theoretic base.

It turns out as they learned more about pulsars they found that a pulsar in a close binary system could pull mater from its neighboring star which would cause it to spin up just as the newly discovered millisecond pulsar and everything worked out and neither Newton nor Einstein had to be kicked to the curb. That's how things usually happen.

It seems from what is now know about current observations that something new must be out there, that is termed dark matter for lack of a better name. So scientists are exhausting this possibility before they start work on that astronomical version of the 100,000 mile per gallon combustion engine.

More rambling to come!

Hubble reveals ghostly ring of dark matter
Circle formed when two huge clusters of galaxies slammed together
By Dave Mosher
Space.com
Updated: 2:00 p.m. ET May 15, 2007

On to: "the difference between String Theory/Supergravity/M-Theory and all the other post-QM physics."

All are attempts to combine the four basic forces of nature, which are: gravity (I don't think that needs explanation), electromagnetism (which is basically the interactions of electrons and photons), the weak force (this is the force that is responsible for most types of radioactive decay), and the strong force (this is the force that holds matter particles together, i.e. it's what holds the proton together, the neutron together, etc.

One more piece to add is that particles can be divided into two general categories: bosons and fermions. Bosons are particles that mediate the four forces. The photon mediates the electromagnetic force. The W+, W-, and Z zero mediate the weak force. The eight colored gluons mediate the strong force. No one knows what mediates gravity, if anything, but it is theorized that it is at least the graviton, whatever that may be.

Fermions would be the electron, proton, neutron, and possibly 100+ others. The other difference between bosons and fermions is that fermions are constrained by the law that the four principle quantum numbers of two fermions cannot be the same. Better known as: two particles cannot occupy the same position and have the same momentum, at the same time. Bosons are not constrained by this.

So far we have only been attempting to show that matter particles are interchangeable. The next step up is to show that the force and matter particles are interchangeabel, this leads to... supergravity, strings, Ms.

Supergravity theorizes that the graviton, a boson, and a theoretical particle called the gravitino, which would be a fermion, are interchangeable. If you have heard the term supersymmetry, the graviton and the gravitino would be supersymmetric partners of each other. The super part is because they are a boson and a fermion. This would mean that matter particles and force particles are really two versions of the same thing and so can interchange. This would lead to the unification of the mater particles and force particles, which would be huge in leading to a theory of everything where all four forces are just different versions of the same basic stuff.

String Theory is a different version of this same thing. It is technically using a very different formalism. One that is useless junk but trying to do the same thing none the less. M-Theory is the latest version of the string theories, since the old string theories don't work. Amusingly in the 1980s the very people who developed the old string theories said that one could not write a conformally invariant M-Theory. Now, well I guess they changed their minds, again.

Trust me, if you never explore string theories or M-Theory ever again you will have missed nothing meaningful to physics.

Stuh, sorry I ran out of time I'll try to respond to you tommorow.

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In my above post I wrote


I meant to say:

So far we have only been attempting to show that matter particles are interchangeable with mater particles, force particles with force particles...

Now I can go back to bed. Boy this stuff gets under my skin!

Thank you very much for your insightful responses TheCorrectResponse.
However, after being slightly insulted, I must defend myself by saying that I was under the impression that there already was a minority of astrophysicists who believe and work on modified Newtonian Mechanics, and that such physics already exists as an alternative to dark matter. I got this idea from my astronomy proffesor, one AP Fairall (whom you might know from the galaxy Fairall9, or maybe not: as he likes to say "People often say to me at conferences 'Oh I recognise the name Fairall, Fairall9 right?' to which he responds 'Yes, and I'm Fairall1'").

Quincy:
I certainly wasn't trying to insult you, slightly or any other way. Based on your interactions I think you are obviously mature enough to realize that. But if you feel insulted, I apologize. If you are just yanking my chain…I'll get you for that

The reason for the offending (or not) comment is that I am always amused at what is taken as the "easiest" solution. Besides areas of science, I am often asked about UFO, the paranormal, ghosts, etc. and am amazed at what people think are the "simple" solutions. Someone saw a light in the sky, MUST be a UFO. Hmmm. Since that particular person couldn't tell the big dipper from the Big Bopper (50s singer), could it be that you simply misidentified the object? Noooooo, obviously it was a UFO from the planet Viltvoodle Six. Well…OK.

A flight of Avenger aircraft goes down on a training flight…must have been intercepted by a UFO; fell into the Bermuda Triangle, etc. Well if you look a little deeper could it be that the particular pilot leading the flight had a history of not being very good, had been lost over familiar territory before, even been lost leading other training missions? But the military in its wisdom let him keep training others? Nooooo it was [place ridiculous REAL answer here] Even if the flight logs and interview with the radio operator at the time corroborates pilot error? Nooooo, it's a conspiracy to hide the truth. Well…OK.

You get the same thing when discussing science, even by scientists, they are just people too you know. A millisecond pulsar is discovered, MUST be left over from 5 past universes. Well…OK. Or maybe we just don't know enough about the new type of object. That was where I was going with the comment; I just didn't want to take up the space to preface it with the above comments. So that's that part.

On to your Professor's comment; at first I couldn't place the name of the Astronomer he mentioned. While having breakfast my brain burped and I do remember, vaguely, that name but this was not a theoretician he was an observational astronomer whose work was mostly on cataloging active galaxies in the southern hemisphere, circa 1980's. It may be a different guy. That is really not important.

The point isn't that theoreticians aren't trying new ideas, including new ways of looking at mechanics. That is what science is all about. It is done all the time by greater and lesser scientists. The great thing about science is that this isn't philosophy so there are experiments to test against to see if the ideas are useful. There is also an inherent gate to keep the really dumb ideas from embarrassing their creators, its called peer review. Someone knowledgeable in the field looks it over first. If it appears to be good science it is published for others to examine. If not it gets shipped back to the author. The proof is in the pudding, or rather, the publishing. This isn't to say nutty ideas can't get into the mainstream, see strings!

The point I was making to your comment about changing mechanics versus accepting something new under the sun, i.e. dark matter, is the following. In my lifetime I am not aware of ANY major modifications to either Newtonian gravity or relativity. I could be way off, but where have they been published? It is true that there have been some minor modifications. New mathematics have been developed that have lead to easier ways of computation, new ways of looking at experimental results, things of that nature, but nothing that fundamentally changes the basis of mechanics. All of these modifications have been well within the basic framework of these theories.

Now I think that you would have to agree that when what you observe is wrong by 90% compared to theory, (it appears there is about 90% more mass that was thought) it would not take a little work around the edges of theory to bring mechanics back into line with observations. You would pretty much need to abandon the old theories completely and start over. This is what I meant by a couple of lifetimes worth of work. And how would you explain the incredible agreement that current mechanics has at all levels and all distances, coincidence? In my opinion that is not very likely.

Since by your last response it appears that your professor may be where you are getting your ideas of the incorrectness of the current state of mechanics, why don't you ask him to point you to some peer reviewed articles that supports his contentions. You could also ask him to point out where either classical or relativistic mechanics have been radically changed over the past, say 50 years or so. I doubt that he comes up with anything. But I could be wrong.

I hope that clears up the point I was trying to make, or at least confuses you to a new and more profound level!!!

And lastly, its good to remember that just because I am posting responses here doesn't necessarily mean that I have a clue!

Stuh...I'm still trying to get to you. But trying to answer in a way that would be useful to you while keeping it conversational enough not to lose non technial people who may be reading along AND keeping myself from looking like a complete idiot is a bit of a challenge..but its comming...I hope it turns out to be mildly worth your patience!

Dark matter/energy is an idea that's been around for quite a while:



http://wmap.gsfc.nasa.gov/m_uni/uni_101matter.html

Mathematical calculations, mostly, on gravity discrepancies.

Of course, other theories could account for the gravitational anomalies in the universe, e.g. the one described here:

http://space.newscientist.com/article/dn8631

Thank you for the links High Seas; the second one explicity mentions the modified newtonian dynamics (or MOND) I was talking about. I found the article particularly edifying, and it cleared up the whole MOND business, as to why it's wrong.
The last paragraph seems to sum it up nicely:

Perhaps this STVG is the precursor to solving the "missing mass" problem. As a layman, all I am saying is that if there are physical theories that rely rather on some modification of the current physics, I personally would rather have that than "dark matter" which is everywhere in abundance and great mass with great gravitational effects, and yet no one can find it or even knows vaguely what it is like.
Btw, I do remember my physics prof. saying that Newton's Laws of motion had been tested down to incredibly miniscule orders of speed, which I wonder if it has anything to do with this:

In fact, I think I am in love with STVG. In fact, I positively am.

I've just read through this with an eager eye, and with GR I guess there must be a large mass to bend light as such. I always enjoy looking at such pictures, where Galaxies look like little flecks scattered about, and they are so incredibly numerous, I can't help but feel an overwhelming awe at the scale of the universe and the amount of matter and number of galaxies/stars there are out there.

Not a physicist! String theory could just be correctly called vibration or wave theory for all forms of energy seems to take the form of waves. Heat is vibration of molecules. Light is electromagnetic waves. Sound is vibration of air particles. Matter is just orbiting subatomic particles but could be seen as waves since circles can be converted to sinusoidal waves. Water pressure on the surface of the ocean form waves. When a hammer hit a steel beam there is vibration which is the metallic lattice work is moving back and forth like waves.

Our view of the universe is perverted by the sense of sight as that is the fastest and most accurate means of sensing the universe. Imagine if we had no eyes then the ears would be the ultimate of sensing the universe. Instead of light, sound would be the measure of the universe and we would say there is nothing faster than speed of sound. Then we constructed a universe time-space model of the universe. Imagine how that would look?

Many of the membrane calculations are probably taken from vibration of plates from, engineering.

A broken theory would be one that explains things in a logical way, but has a problem. Not only does it seem like GR has problems, but it doesn't seem to even explain gravity. Saying that "warping spacetime does it" and throwing up an equation for the attraction between two objects does not explain why there is an attraction.



I do not know what method the surveyor is using the calculate the distance from New York to Rio, but based on your tunneling through the Earth comment it sounds like he is measuring the tangent distance between the two points on the sphere of the Earth, whereas a walker follows an arc on the surface of the Earth. Even in a Euclidean geometry a tangent line is shorter than an arc between the same points, so I do not see what your point is.



Hm. Well, to me, GR seems highly inelegant. Perhaps this is because I do not understand it. But then again, I don't know of anyone who really does understand it. From what I've heard, even Einstein did not understand it. Do you really understand it?

I have several majors issues with it. The first problem I have is that nobody can explain it, even advanced physicists that I talk to. I don't care what the results of the equations are, because I am only interested in understanding the theoretical concepts and not using them to make predictions. Equations are merely a formalized notation for real concepts, so when people rely 100% on equations and cannot explain what they physically represent, I am wary.

1) Both the concepts of inflation and GR move matter via the "warping" of spacetime, which as I understand it, is the "coordinate system" of the universe. Several such examples come to mind.

For instance, "light moves in straight lines or geodesics and it is really just spacetime that is curved." Or, from the famous Ripple in Time, "imagine the 3 dimensional universe existing on a flat plane; the closest distance between any two points is achieved by bending the plane so that the two points are touching each other." No, because that is only the closest distance in the embedding coordinate system, the one where our coordinate system appears as a surface. Well, you might say that's from science fiction...but GR seems to supports this kind of thinking. For example, wormholes with the Einstein-Rosen Bridge. For another example, the Alcubierre warp drive that. That's from science fiction too, but the premise of it, which is to create a bubble in spacetime that compresses spacetime in front and expands it behind to carry mass from one point to another faster than light could get there, is supported by GR. Now if it were even possible to create such an effect, that still does not make sense...if you squish some graph paper together there are still the same number of squares connecting the two points, so to take that last little "step" out of the warp bubble would be the same distance you had to travel to begin with.

Basically, my problem is that coordinates define position and distance, so if there is a measurable change on the position of some particle, then that particle must have changed its coordinates, which is the same as saying that it moved with respect to its coordinate system.

Now here's for an analogy of my own: draw some dots on a piece of graph paper, and then start bending the graph paper around every which way. Do the dots start sliding closer to each other within the paper? Of course not. So why should warping spacetime induce motion in otherwise stationary particles?

2) There are 3 (or 4) fundamental forces, and we have identified bosons for all of them except gravity so far. It stands to reason that gravity, which follows an inverse square law, and has a propagation speed of c, would be mediated by a particle that has a speed of c like all the other forces. Why do we have 2 completely different explanations for 2 effects that are virtually identical? The only difference between gravity and the other forces is that we assume gravity has no maximum range (which, by the way, if it is true would seem to nullify the graviton theory on a fundamental basis because any virtual particle's range is limited by its speed and the uncertainty principle). But I consider that to be a naive assumption, because we are not capable of measuring the effects of gravity at extreme ranges, and they become so negligible at long ranges that the universe would have no noticeable effect if gravity did had some extremely long maximum range. I think sometimes we have to use a grain of logic instead of just applying inductive reasoning out to the infinities of preposterousness (like assuming that the universe doesnt have an edge just because we can't see it, another completely non-falsifiable assumption).

3) The next problem I have with gravity is that I cannot visualize exactly how spacetime is purportedly deformed by it. In the diagrams, spacetime is drawn as a plane, and a massive object is depicted as resting on the plane like a basketball on a piece of 3-ply charmin towel. Is it more correct to say that mass reduces the "density" of spacetime and stretches it out in all directions from itself?

Why does just about every physicist believe in GR? Is it because it accounts for all the things Newtonian Mechanics, and more, with greater accuracy? I'm not a physicist. If physicist were to find another theory to explain gravity that "made more sense" as in human common sense, but made exactly the same predictions as GR, would they choose the new theory over GR? (Yes, wildly hypothetical, I know). Why should physical laws be something we can easily understand unless for our own sake, but then again what are theories for? For accurate modelling and prediction and/or understanding physical processes in the univers?
I suppose everything is postulation. Mathematics is always reduced to axioms taken as "self-evident truths", there is always a level where mathematics cannot be reduced further. So it is for physics (again I speak as an enthusiastic laymen); all theories are based on "axioms" which are necessitated by observation, as in the paradigm shift from "classical physics" to quantum physics. GR has space-time which is in some sense pliable.
I cannot remember where I read it, but some physicist said something along the lines that GR can be understood by physicist, but no-one really understand QM, and yet no-one is pointing a finger at QM.


Some parts of theory are mathematically deduced from accepted theories, and the deductions tested for validation. To my knowledge, theories are grounded in a posteriori reasoning, and a priori reasoning applied to new predictions that can be tested. Is this not the case for GR?
Newton observed the motion of the planets, from where he mathematically deduced the gravitational law. Newtonian Mechanics was succesfully applied to particles the give us classical thermodynamics and a theory of gasses.
I think analogy must never be taken too far. Analogy is ok within certain limits of understanding where and how you want to apply it. As my friend said to me recently: " The Big Bang was an explosion right? (ofcourse meaning it was analogous to an explosion). So wouldn't there be a sound from the Big Bang? Wouldn't we need some reaction to cause the universe to explode? " Ofcourse the Big Bang is a theory, but we can see where this guy went wrong; he took the anology too far. I don't know to what extent paper is analogous to space-time. To my understanding, GR would have gravity reducing the scale of the co-ordinates systems, greatly at short distances and less so further out, I could very likely have the completely wrong idea though.
Does the electromagnetic force have a maximum range (I know very little of the other two)? How do you suggest gravitational forces are mediated Stuh505

Quincy, not all physicists believe in GR. Have you heard of the standard model?

http://en.wikipedia.org/wiki/Standard_model

It is a very popular theory that just about everyone believes in for explaining how all the other forces work. Look in the diagram. See the graviton particle? It's a theoretical part of the standard model.

http://en.wikipedia.org/wiki/Graviton

A lot of people believe in the graviton...but the graviton provides an alternative explanation for the force of gravity. To quote Wikipedia, "In other words, general relativity and the standard model are incompatible."



Just because you have a reason for believing something that makes sense doesn't mean your belief is correct. It is amazing how, when doing a simulation, one can often account for just about any anomaly through some logical deduction...only to find out later that it was from a bug in the program. Invariably, whenever a guess is made, no matter how much evidence there may be for that guess, that guess will usually turn out to be wrong in some way.



First of all, saying the big bang was an explosion is not an analogy -- it is just 100% back-asswards. The only people who use this "analogy" are religious Intelligent Design fanatics who are trying to slander the theory. No scientist would use this analogy, because an explosion is caused by some reaction that causes a force to push particles apart, whereas the big bang theory is saying that spacetime is simply expanding -- and that there is no force pushing things apart, in fact the force of gravity is trying to pull things back together.

Now, on the Big Bang having made a sound, supposedly it did make a sound...and you can hear a synthesized version of it here:

http://faculty.washington.edu/jcramer/BBSound.html

An analogy must make sense on some level for it to be a valid analogy. I believe I was considering the analogy at the most basic, straightforward level...and simply showing that bending the coordinate system does not make sense, so either GR does something totally different, or it is totally broken. The Einstein-Rosen Bridge and Alcubierre warp drive are actual examples of things supported by GR.



Yes, the attractions and repulsions of the electromagnetic force are caused by the exchange of massless bosons called photons that are exchanged between two particles. Unlike regular photons these are virtual photons which exist "because they can"...the uncertainty principle says that the amount of energy is not definite, and therefore small particles can pop into and out of existence for short periods of time provided that their energy does not exceed the uncertainty limit. This imposes a time limit on how long the particle can exist for. The virtual photons travel at speed c (like regular photons) and have a maximum lifetime, so therefore by distance = rate*time that tells you what the maximum range is.

Personally, I am a bit confused why there is actually a limit though, because the energy of a photon is E = h*c/lambda, where lambda is the wavelength. There is a short wavelength limit and that is the Planck length, but there is no long wavelength limit, and therefore no limit to how small the energy of a photon can be, and therefore no limit to the amount of time a photon can exist for, and therefore no limit to the distance it can travel before having to cease existing. One possible explanation is that perhaps virtual photons cannot "choose" their wavelength, but that they are created with some probability density function with mean at some finite wavelength.



I offer the suggestion of the graviton as an alternative theory, but I personally do not have beliefs in areas of science that lack sufficient data.

I have heard of the Standars Model, but I never thought it was an alternative to GR, just as QED is not really an alternative to the electromagnetism of Maxwell (or is it?).


And then

So what is the difference between the SM and string theory?

"You look like a million bucks!" Yes, green and crinkly.....

And what about the Cosmic Inflation? Where does it fit in with the Standard Model and GR? Is there proof for Cosmic Inflation? Or does it just happen to explain the observable universe and the fact that the universe has matter and energy? Where does dark matter come in to Cosmic Inflation, ie. where/how was this dark matter created and is it accounted for as yet?