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Need recommendation on alternative thoery/reading

  1. Oct 12, 2012 #1
    I have decent understanding of GR/SR explanation of our universe's laws, however I feel that the theory basic concepts and imply complications which are making simple problems (like twin paradox) appear more complicated than they should.

    I understand that there are alternate theories that do not generally conflict with relativity but are have different "rules" which make them easier to comprehend.

    The theory would be fully compatible with observed measurements but have different rules, concepts, basis of thought/formulas preferably close to these:
    - Preferred/Universal "frame" is is one of a body at "rest" where rest is defined to be at rest wrt CMB at this epoch. That frame has "universal clock rate" and defined speed of light.
    - Universe is not expanding
    - The clock rate of the universe is universally changing over time (compatible with experiments)
    - Distances and space coordinates/positions are absolute and not curved
    - Time is relative and its effect broken into two: into clock dilation and event propagation delay
    - The clock is dilated and AND events delayed in gravitational fields. Clock dilation and event propagation speed are curved in gravitational fields.
    - Moving objects have "absolute positions" in universal frame at any point in (universal) time's snapshots.
    - Moving object's clock is slowed.
    - Moving object's shape and "perception" is altered wrt that one at rest

    My problem is that I don't like to read formula-heavy readings. Formulas are there for scientists and experiment confirmations. General public doesn't need those. So please be mindful of that when recommending :)

    I apologize in advance if this is not the forum to post the request. Feel free to move my thread.

    Thanks
     
  2. jcsd
  3. Oct 12, 2012 #2
    No. GR does not put in place unneeded complicated answers, in fact it solves things with incredibly simple answers. Also, look over some of the things you posited. You'll realize that most (if not all) of the things you said actually complicate things.

    It's sort of an unspoken rule in physics (and definitely a rule in math) that you want to start with the fewest and the simplest axioms possible and be able to derive as much as you can. Starting with really just two axioms (The second postulate of relativity and the equivalence principle - I find the first postulate superfluous) you can explain the entire universe pretty much. No other competing theory is nearly that beautiful.
     
  4. Oct 12, 2012 #3

    Mentz114

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    You have my full agreement on that. Unfortunately 'beauty is in the eye of the beholder'
     
  5. Oct 12, 2012 #4
    I think that if you summarize the relativity principles they end up to be not comprehensive to an average human brain and especially hard to visualize as our brains are "built" to perceive up to three dimensions.

    If we were to "flatten" the dimensions we can answer a few questions that are complex to explain with SR with ease (some may not be correct, so that's why I was looking for a reading):

    Q. How big is the black hole?
    A. Zero.

    Q. How big is the black hole's event horizon?
    A. Zero.

    Q. What happens as you fall into a non-evaporating black hole.
    A. As you approach the black hole, your clock slows, shape becomes more pointy. As you approach the black hole you perceive the universe progressing faster (because of your slowed clock). As the universe progresses you approach a point in time at which both your and universe's clock rate become zero - end of the universe.

    Q. How long does it take to reach the end of the universe.
    A. Never because as you accelerate, your clock rate decreases and you perceive the universe progressing faster, but as it progresses faster its clock rate decreases and counters your acceleration.

    Q. Twin paradox?
    A. There's no paradox.

    Q. Lorentz transformation?
    A. There's none

    It could be just the way my brain functions, but I am really having difficulties with SR. I am especially having difficulties with explanations like "distances reduce as you travel with higher speed". As if I take the universe in my pocket and it suddenly changes... Or the flat out "you can't travel faster than speed of light" - I can reach alpha centauri in 1 year, where your turtle light will take 4 years to get there. You can't communicate FTL, but but certainly you can get there faster.
     
  6. Oct 12, 2012 #5

    PAllen

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    Well, one difficulty is that almost all of these are wrong.

    I assume you mean GR, as the whole topic of black holes is outside of SR.
    Depends on what you mean. The horizon, as perceived from outside, has a definite size and surface area. The singularity can't be seen from outside. The singularity has no size because it is not part of universe (manifold). However, you can present limiting arguments that the singularity for a non-rotating, neutral BH has zero size.
    False. See above.
    False. Someone falling into a BH crosses the event horizon in finite time on their watch, and (after crossing) continues to see the outside universe evolving at a normal rate (a bit slower or faster depending on the exact infall trajectory).

    It is true that as you approach the singularity you are stretched by tidal forces.
    What do you mean by the end of the universe? Do you mean how long would a uniformly accelerating rocked take (by its own watch) to reach the most distant galaxies? This depends on the expansion rate, and whether the universe is finite. On the other hand, the time measured by a clock inside a rocket uniformly accelerating at 1 g to reach a galaxy 1 billion light years away would not be long at all.
    Correct. Many explanations, no paradox.
    What?!!
    You can reach alpha centauri in 1 year of your time on a fast enough rocket. However, if you raced light, you would lose. Light takes 4 years to get their measured in the sun - alpha centauri (A.C. from now on) frame. In this frame, you take well over 4 years to get there. Within the rocket, if light signal was sent from earth the same time as you launched, to a mirror on A.C, you would intercept the reflected signal before reaching AC - thus you agree that the light beat you there.

    It seems to me that part of your difficulty is that understanding nonsense is a lot harder than understanding what relativity says (though I don't claim this is easy either, especially GR).
     
  7. Oct 12, 2012 #6
    You could tell me something I don't know.
    You didn't even try to understand what I was saying.
    Please refrain from assuming that someone who doesn't understand black holes as well as you do doesn't understand basic concepts. Black holes are complex to understand. That is why I need reading with different interpretation.

    I know that i'll lose against a light beam. The problem is in wording and understanding whether faster means covering known distance at a rate faster than 1 light year per year or what it relatively means. Who says that I wanted to race light? I just want to slow my clock.
     
    Last edited: Oct 12, 2012
  8. Oct 12, 2012 #7

    PAllen

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    I made a great effort to understand something that was expressed in a very unclear way. Perhaps if you tried to frame clear questions about things you don't understand (rather than saying: relativity is too confusing (even though I don't understand it), give me something else instead.

    Note, I confirmed things you already knew because you had a few true statements among many false ones, so I wanted to indicate both which were true and which were false.
     
  9. Oct 15, 2012 #8
    I appreciate you trying to understand what I mean... Maybe you understood my points as questions, where they were statements (most likely incorrect ones) but when translated into coordinate space that is flat in terms of space but variable in terms of time.

    The problem comes with conflict of philosophical and mathematical thought of physicists which goes to the point of being hypocritical. Hypocritical in a sense that relativity seems to advocate that time and simultaneity is relative, but yet seems to prefer the falling observer when explaining black holes, but then a distant observer in some other case. Preferring the falling observer doesn't make much sense because it assumes that the universe is static, but then it prefers the distant observer in case of evaporating black holes.

    And here's what I mean (F philosopher -- M - mathematician/physicist):
    F: You are saying that you can safely create a micro black hole on earth.
    M: Yes, because it's an evaporating black hole and it will instantly evaporate.
    F: It will evaporate while you and I are alive?
    M: Yes in a few moments in fact.
    F: So it's safe?
    M: Yes
    F: So you'll create a black hole which by definition will have an event horizon?
    M: Yes
    F: So a definition of event horizon means that gravitational force is so strong that even light can not escape it?
    M: Yes
    F: But if a body is falling into a black hole, we see it fall in but never reach the black hole. If we were to measure distance to it it would be nearing infinity.
    M: Yes
    F: But this black hole will evaporate and not in infinite time?
    M: Yes
    F: And by definition of a black hole, if we an event were to hapen near the event horizon, it may take billions of years to reach us?
    M: Yes
    F: Then it's safe to say that the black hole's EH is billions of light years from us?
    M: No. Because a falling observer would reach the black hole in finite time.
    F: No? So how do you know what will happen to the falling observer when you never saw one fall next to you?
    M: We can extrapolate that from the formulas because a falling observer would reach the black hole in finite time. The falling observer that is say a point-like mass would appear to fall into the black hole "normally".
    F: So you can predict the future and say that the falling observer falls into the black hole before the universe ends?
    M: Yes
    F: And lets go back to the micro black hole ... You said previously that you can make a micro black hole that will instantly evaporate. But yet, by definition an event that's near the black hole EH will take billions of years to reach us?
    M: It will reach us in moments because the mivro-BH will almost instantly evaporate. It will not in fact take billions of years because of geodesics blah blah and light cones blah blah.
    F: What? But the near EH event will "observe" a body with infinite gravitational force behind the EH.
    M: Yes
    F: But you said the speed of gravity is C. Because the distance to EH is infinite, hence the event can not receive that information that BH evaporated in finite time.
    M: It will , because the BH will evaporate. It will not in fact take billions of years because of geodesics blah blah and light cones blah blah.

    And now I continue on and on about how how all this doesn't make sense, but my arguments will probably not make sense to you. It all sounds to me sometimes like someone playing the same broken records and it's likely that our newbie questions sound the same to you.

    To this date, after fairly frequently visiting forums, i have yet not found many answers that are philosophically correct.

    I did ask such a question once and all I got was " It will not in fact take billions of years because of geodesics blah blah and light cones blah blah.", and I can't understand that.
     
  10. Oct 15, 2012 #9
    Well unfortunately for you a rigorous answer will probably require invoking those ideas. It seems to me that your denying the adequacy of answers because you don't understand them, but that is like me saying that someone doesn't speak spanish because I can't understand them and confirm it's spanish.

    The only thing I'll say is that it's not that an outside observer will think the falling body will take infinite time to reach the event horizon, it's that the light will be delayed so that it looks like the body will take an infinite time, not that it actually does.

    I think you have a few other misconceptions but I won't bother trying to explain them if you won't take the reasonable (and correct) answers that involve the math of GR.
     
  11. Oct 15, 2012 #10

    pervect

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    I rather supsect Kamenjar would understand SR if he put 1/4 as much effort in studying it trying to understand it, as he did trying to "find problems" with it.

    But I could be wrong. It does take high school algebra to understand SR. It also seems to me that if you don't have high school algebra, it's not going to be very profitable to study physics and ask questions about it - and that one would be better off doing something else. Whether that something else be "liberal arts" or getting the basics (such as high school algebra) first, before trying to tackle the physics.

    Meanwhile, I'll just add that PF isn't a good place to look for alternative theories - you can find th em all over the net if that's where one's instrest really lies.
     
  12. Oct 17, 2012 #11
    Einstein never explained thought problems with formulas and abstract terms. Also, physicists have no issues with alternate theories which don't conflict with SR/GR.

    I don't have a problem with GR in general. I have a problem with people like you who don't question anything.

    I in fact have a BS degree, and had calc 2 and matrix algebra back then, which was looooong ago. I also have IQ of over 130 and given the quote that sometimes great minds think alike, I can't say much about yours.
     
  13. Oct 17, 2012 #12
    I question many things. I don't question things which have been questioned, and held strong.

    What you are questioning falls under that second catagory.
    If you wish to ask about GR, because there are areas you do not follow, PF is a perfect place for it. But you have to ask in concrete questions (not conversations with yourself), which you haven't. And you need to realize that if you ask complicated enough questions, you'll get answers you might not understand, which it seems you won't accept.
     
  14. Oct 17, 2012 #13
    Fair enough. Maybe I ask something that is not concrete enough. I ask here because I see that this forum has the brightest minds that actually have the capacity to contribute - refine the "generally accepted" or question things.

    Thanks all.
     
  15. Oct 17, 2012 #14

    tom.stoer

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    kamenjar, do you want to try to understand physics? Or do you want to understand something else b/c physics is too complicated?

    Suppose I am hungry and I want to prepare a meal. Unfortunately the fridge is empty - but wait - there's my iPad. So instead of preparing something to eat I decide to visit the physics forum. I am still hungry, so that's not reasonable, is it?

    So if you are looking for alternative theories instead of GR b/c you don't understand GR and b/c you don't want to try to understand GR, that's definitly the wrong place to ask and to discuss, I am afraid.

    So what is your intention?
     
  16. Oct 17, 2012 #15
    First of all, thanks for helping me out with some of the questions that I had.

    To answer your main question - I'm trying to visualize. I know it is difficult for a 3D-trained mind to do so, and I am not finding many resources that help with that.

    In particular, I am interested in cosmology (space expansion), relativistic speeds and gravity's effect on space-time and what that all means at molecular level. The fact that we know little about what is causing some of these effects is intriguing to me. I read most of the relevant chapters of "The Fabric of the Cosmos: Space, Time, and the Texture of Reality". I found it educational, but didn't find too much there.

    The eating problem comes from not being able to order anything that you like. So you are stuck with Wikipedia's "interpretation" of the Twin Paradox and other explanations that will explain it totally differently. The closest thing to a resolution that makes sense is what I found was on this forum. Another problem is that if you eat McDonalds when you are a kid, that's all that you'll enjoy eating all your life. So it's good to try Chinese or India once in a while, if you are getting my vibe here :)
     
  17. Oct 17, 2012 #16

    tom.stoer

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    OK.

    Studying physics always means to understand what physics is not. Physics does not explain how the world is and why it is the way it is. Physics is about (mathematical) models to predict and explain measurable / observable phenomena. In our case GR does not say that spacetime is a 4-dim. Riemann manifold with blablabla, but physics says that we can correctly predict results of experiments and observations if we use a specific mathematical model of spacetime, namely a Riemann manifold plus a set of equations (Einstein equations, geodesic equations).

    Now there's choice.
    A) You can try to get some insight into the physics, i.e. to understand to a certain extent what the model of spacetime is about.
    B) You can decide to understand something else, what you might call an alternative theory. I guess what you are looking for is a layman explanation of A) So you are not looking for an alternative theory, but for a better description of a well-established and testd theory (here: GR)

    A warning: As I said physics is about mathematical models and their relation with experiments. As soon as you start to trust in layman's explanations there's always the danger that you are not discussing the (mathematical) model but a model for a model (for a model ...). And your problems might be unrelated to the details of a (mathematical) model, but may be due to intrinsic problems of the model for the model.

    So for all explanations on terms of everyday concepts there's always a caveat: don't waste your time with intrinsic problems of the everyday concepts; invest your time in the underlying physics. This is true even for excellent writers like Brian Greene.

    If you now try to simplify things even more than you will be lost. Believe it or not, w/o understanding the math you will not be able to construct models that are both simple and correct.

    With these warnings in mind you can start to ask questions like
    1) what are concepts to define the size of a black hole? what's the result?
    2) what happens when falling into a black hole? what will you observe?
    3) what does it mean that an observer in free fall will cross the event horizon in finite proper time? whereas a static observer outside the event horizon will never see the other one cross the horizon?
    4) what is the twin paradox? how is it resolved? (there is no paradox)

    What you should not do is to discard concepts like curved spacetime b/c you don't understand it. What you should not do is to rely on flat space b/c it's simpler. Unfortuantely there is no such model; we would use it - and we would safe lot's of time, paper and money ;-)
     
  18. Oct 17, 2012 #17

    pervect

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    While we're preaching (to what effect, it's hard to say, bu one can hope for the best) another thing to avoid is misunderstanding relativity, and spending a whole bunch of time and effort demolishing a straw man version of relativity.

    The straw man version of relativity is indeed quite wrong. But the problem lies with the construction of the straw-man.
     
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