Or ... Ebtx takes a beating but keeps on ticking
Thank you for maintaining your excellent cosmology site. I know it's a lot of work to keep such a thing going without quitting your day job. I have a question: In your cosmology FAQ, under "Why doesn't the solar system expand if the whole universe is expanding?" , you state "The galaxies are receding from us because they started out receding from us ..." and further ... that the spatial expansion has no significant effect on matter up to the scale of galactic clusters..
Then in another place ("Why do we think that the expansion of the universe is accelerating?") you give some current reasons for believing that the expansion is accelerating. Apparently the expansion affects matter (type 1a supernovae) enough to cause them to participate in a gross acceleration yet the expansion has negligible effect on intergalactic distances within clusters. What is inferred here? If the expansion accelerates matter ... then ... it must affect matter, i.e. matter moving through space is affected by that space in such way as to cause the acceleration. And ... the acceleration is proportional to the expansion, i.e. a galaxy at great distance must accelerate faster than one nearby else the distance between the two would close as a percentage of the Hubble radius. Hence, the idea of proportional expansion ... meaning that, if the universe doubles its size, the solar system must also double its size in lock step. But of course, it doesn't. Therefore, there is something preventing it from doing so. It isn't exactly that the expanding space has no effect, it's that the effect is mostly supressed by some factor "x" at distances less than galactic cluster scale. Is this a correct interpretation of current thinking? One more question: In the same FAQ "Are galaxies moving away from us or is space just expanding?" your answer was somewhat startling. I did not expect an all but explicit statement of "theoretical equivalence" (two distinguishable ideas producing indistinguishable results and therefore being equally valid in a strict logical sense) ... between moving through space as in an explosion and having the space between two positions increase ("general relativity explains how to transform from one view to the other ...") Why not deal with another alternative which must necessarily produce the same indistinguishable result. Namely that the "matter constructions" of the universe are getting smaller ... which is necessarily equivalent to the above? Thus, A___BC___D >> A___BC___D is equivalently to A___BC___D >> A_BC_D Then, it is readily understandable that one needn't resort to expansion into a 4th physical dimension. Why isn't this alternative discussed as a purely geometric [not HoyleNalikar] equivalent? Perhaps shrinking is more distasteful than expanding? Alice seemed to have more trouble with shrinking than with expanding ;o)
Second email: 020401 Thank you for your prompt reply. But, I'm looking for something else here. Perhaps if I rephrase it in more fundamental terms. What I really want to understand is the interplay of matter and space ... as interpreted by professional astronomers and cosmologists. From your reply, I get the impression that space is simply a passive receptacle for matter ... a pure abstraction ... having no physical properties which bear upon physics. In other words, the universe of matter above the cluster scale expands, and we know so by indirect measurement of the quantity ... "distance". But ... space (our qualitative conception of "distance") has no interaction with matter ... it doesn't "carry" matter with it or "do" anything at all. And ... the gravitational force is an interaction between particles ONLY and the extra repulsive lambda element is also a property of matter and not of space. If this is the general professional outlook on the subject of space, I can understand your reply. If not, I'm still in the dark about what is actually studied. This may be the main sticking point in explaining the expansion of the universe to the average person. From numerous other articles over the past few decades, I have gotten the impression that in the standard model, space carries matter with it, i.e. interacts with it in some fashion. Also, the concept of "vacuum energy" further confuses the issue by implying that there is a "something" within or about it which could, in effect, generate a spacematter interplay thus elevating space from the status of passivity to one of "active ingredient". Am I getting any closer to understanding your viewpoint?
Last email Feb 13, 2001 My God ! Are you actually saying that professional astronomers, physicists, and cosmologists have no understanding of nature except in terms of mathematical symbols? There are no geometrical concepts to back them up? No logic? Or do you mean that you are incapable of transferring, in words, your personal understanding of basic concepts? I don't mean to disparage your career, but what am I to think? Has modern science abandoned geometry, i.e. visual percepts as the basis of reason? You give the Galileo quote about mathematics ... yet he knew less math than I. Do you really think he would underwrite an explanation of existence which could not be conveyed to the average freshman college student?
If science has nothing to offer the general population other than a cryptic remark to the effect that you have to master the "language of the mystic experts", I think science is just about done at the theoretical level. All professional scientists who work at the theoretical level should remember who they are working for (I mean here their salary). You and others are paid out of the extra cash left over after the basic needs of civilization are taken care of. You can have a career in these fields only insofar as you "produce" answers understandable to at least a large proportion of the public. Failing this, you may continue to study on your own and at your own expense ... without the expensive billiondollar tools of scientific exploration. I as I have said in other places, nowadays the more money that's spent on theorists ideas ... the less return there is on that investment. 99% of advancement in science to ~1920 ... at the theoretical level ... was obtained at a total cost to civilization of ... nothing ... zip ... nada ... and all of it was reasonably understandable without any math whatsoever ... just a worded description of the phenomena.
Now you say you can't say whether your own idea is one of two simple alternatives. You need a 3rd ... You know, I'm the same age as you. This kind of "answer" doesn't cut it with me. Maybe a student or housewife can be intimidated by such cop outs. And yes, I know I emailed you. You didn't come to me ... and you certainly have no obligation to me. But you are an accessible representative of the profession by your own design (your web site) ... so ... speaking generically ... you ought to try to do better than an "appeal to authority". Spend some time thinking about what I have said. Look at my web site (ebtx.com). If you think I'm just another wacko' ... perhaps you're right, you wouldn't be the first one ... that's OK by me. Then ... send me a proper answer ... I'll give ya' two months. Then ... I'll cross your name off my short list ;o)
Well, I give up ;o(
Obviously, I can't even get him mad. If you have questions about cosmology ... visit his Cosmology Tutorial ... you might find it there. If not ... forget it. Well, what's going on here? Clearly, he got the best of me. I let my guard down with the expectation that I might find a spark of Leibniz somewhere out there. I used to do that a lot when I was younger ... but I seldom do it anymore. And that's the pity of it. As you get older you get wise to the ways of the world and kind of "clam up". I was hoping that he would not answer for a long time or at least not at all. To get an answer the next day is the worst possible scenario. It means there is no understanding here of my position at all. A complete "dead zone" ... the vacuum state ;o( Let me illuminate the basic problem The mathematics which describes physical processes is a "subset" (B) of the whole of mathematics (A). This means that some part of mathematics has nothing to do with physical reality. If you believe this as I do, you will be at odds with the establishment because they believe that mathematics (A) is logically congruent with physics and that therefore anything deduced or induced mathematically from the subset (B) must necessarily find its expression in reality, i.e. mathematics is reality ... not just a description of it, qua subset. This position allows them to construct mathematical "floating abstractions" which are defined as valid physical propositions upon which to base predictions concerning the results. The fact that their predictions more often than not don't work out in reality does not dissuade them from the above proposition (that mathematics A is congruent with that reality). By the term floating abstractions, I mean specifically those concepts (or mathematics) which is not directly connected with "visual percepts". These are geometrical abstractions derived directly from experience which by mutual observation (and consent) are defined as valid constructs; like ... point, line, plane, solid, movement, rotation, expansion, threedimensional, etc. To convey information in physics it is necessary to be able to reduce that information ... in terms of ... such constructs ... else it cannot be known to be logically valid with any comparable degree of certainty. What happens when floating abstractions are employed as tools of cognition? Any fact that we discover can be reused as a tool to discover more truths. The greater our knowledge becomes the more we are empowered to discover yet more. When we employ such a disconnected piece of "knowledge" we run the risk of entering the realm of 2nd degree speculation or even 3rd degree. Let me explain. 1st degree speculation is what you must do to generate ideas as to what the answer to your question might be. Suppose you find that there are ten basic ideas from which to choose. Now you must conduct experiments to determine which of the ten correspond to reality. But suppose you just assume one proposition is true and speculate in the 2nd degree about what the consequences of that proposition might be? And you find again ten alternatives. You now have only a 1 in 100 chance that one of those new propositions corresponds to reality. Now you begin to sound like you don't know what you're talking about as in the above (N.Wright) statement ... "Distance is not a property of space." Now if you go to 3rd degree, you will be speculating on one of the 100 ... and finding 10 more possibilities, your chances of being correct are now only 1 in 1000. If now you speak your piece ... someone may call for the men in white suits to take you to the "bin" for observation ;o) This is what must inevitably happen when you get too far away from "visual percepts" in the realm of physics. This is what has happened in cosmology and physics. They talk of axions, wimps, 10dimensional space curled up ... and other such nonsense which has no relation to anything in the perceptual realm. And ... if you press them ... they will in fact hide behind their mathematics and state that you cannot understand it without a deep understanding of mathematics. There is a little secret in all this which is somewhat amusing. These people don't do mathematics (as in fugure it out). What they do is use a calculator or computer or mathcad type program to do it for them. Prior to the electronics age they looked up the answer in tables for a generic answer and adjusted it to their problem because the math itself is just too difficult. The actual math is done by mathematicians persuing math (A) as a pure abstraction without any intention of implying that it was in fact all math (B). You don't have to know how to do math to be a scientist. You just have to understand the basic principles acurately and "look up the equation" ... then present the result as "your math".
The constant paean to mathematics implies that scientists can "sight read" the language of mathematics. This is the purest form of BS on earth. There haven't been perhaps ten men in our history who could do this. Maybe Euler, Gauss, and a few others of that caliber.
