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Thread: The basis of modern cosmology

  1. #1 The basis of modern cosmology 
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    There seem to be numerous people who come here and post opinions to the effect that mainstream cosmology, in particular the big bang hypothesis, is wrong, offering no rationale other than that is inconsistent with their personal belief, and then take offense when they are told that their characterization of the theory is factually wrong and they don’t know what they are talking about. They criticize their critic as arrogant.

    The true misplaced arrogance lies with the poster who presumes on the basis of his so-called “common sense” that the work of an army of dedicated physicists based on over a century of theoretical, experimental and observational work, and not a few Nobel Prizes, is wrong. In the meantime the OP, hereafter known as “the fool”, misrepresents the mainstream theory, which he understands not at all, and makes criticisms that violate principles that have been well-established since the eighteenth century and are known to high-school students. The fool fails to understand that he does not understand, but is unwavering in his opposition to a theory about which he is clueless.

    These people should have to pay for air.

    Make no mistake, the modern theory of cosmology is a work in progress. But it is a work with a solid foundation.

    The pillar of modern cosmology is one of the pillars of modern physics, general relativity.

    General relativity (GR) was formulated by Albert Einstein and announced in 1915. It has since received a great deal of attention, the mathematical foundations have been examined, the presentation refined, and a host of confirming experiments performed. General relativity, with its mathematical roots in Riemannian geometry is a formidable subject, and some of its predictions are contrary to everyday experience – i.e. “common sense” can be badly mistaken. That is no surprise as even special relativity, the precursor and “little brother’ of GR is surprising at first encounter.

    http://math.ucr.edu/home/baez/gr/gr.html
    http://en.wikipedia.org/wiki/Introdu...ral_relativity
    http://en.wikipedia.org/wiki/General_relativity
    http://rspa.royalsocietypublishing.o...732/5.full.pdf

    GR treats the universe over all time as a single entity – spacetime. This can also be done in Newtonian mechanics, so there is nothing really new about spacetime. What distinguishes GR is that spacetime is not just affine 4-space, but in fact is a Lorentzian 4-manifold of undetermined topology, with a curvature tensor that is also unknown but is determined by the distribution of mass/energy via a stress-energy tensor defined by a very complex set of partial differential equations. These equations, the Einstein field equations can only be explicitly solved in a few simple circumstances. Gravity is the result of curvature of spacetime.

    In general because of curvature neither space nor time have any global meaning. However, if one makes the assumption that spacetime is homogeneous and isotropic, then spacetime decomposes as a 1-parameter foliation by space-like 3-dimensional hyperplanes of constant curvature. The parameter serves as a surrogate for time and the hyperplanes as a surrogate for space. The hyperplanes inherit a true Riemannian metric from spacetime and expansion of space means that the distance between points increases as the value of the time-like parameter increases.

    Astronomical observations support the assumption that the universe is homogeneous and isotropic on the largest scales. Observations also support the expansion of space.

    http://scienceworld.wolfram.com/phys...eConstant.html
    https://www.cfa.harvard.edu/~huchra/hubble/
    http://map.gsfc.nasa.gov/universe/uni_expansion.html
    http://map.gsfc.nasa.gov/
    http://en.wikipedia.org/wiki/Wilkins...isotropy_Probe
    http://aether.lbl.gov/www/science/cmb.html
    http://aether.lbl.gov/www/science/cmb.html

    Based on these assumptions and observations Hawking and Penrose in a series of papers used general relativity to conclude that, as a logical consequence, the universe began in an extremely compact form, and in fact predicted singular behavior (which is generally thought to indicate a limitation of general relativity to predict the first fraction of a second)

    http://web.archive.org/web/200806150...ng_text.shtml/
    http://rspa.royalsocietypublishing.o...7-91869da35ea6
    http://rspa.royalsocietypublishing.o...7-91869da35ea6
    http://rspa.royalsocietypublishing.o...7-91869da35ea6
    http://rspa.royalsocietypublishing.o....full.pdf+html

    So, while nobody knows what happened in the first fraction of a second, the big bang hypothesis in terms of subsequent expansion from an extremely compact state is on firm empirical and theoretical grounds.

    Inflation is not necessary to the big bang, but does use ideas from quantum field theory to explain why the universe is homogeneous on the large scale, yet exhibits anisotropy on smaller scales. It is not a fully verified, or even rigorously formulated, theory, yet. It is promising. It is supported by what has been seen in surveys of the cosmic background radiation. Attacking inflation as unproven is futile, because it is well-known to be just that. But interpreting “unproven” as fanciful or unlikely is simply a demonstration of ignorance.

    http://web.mit.edu/physics/news/phys..._cosmology.pdf

    Thus, modern cosmology rests on a solid foundation of empirical data and well-formulated theory. That does not make it immutable. Any physical theory is subject to refinement and extension. But any revision must meet equal standards of rigor.

    The fool who rejects modern cosmology must meet the obligation of providing the basis for an alternative . That means providing a theory of gravity to replace GR, and the empirical data to support it. Further, that data must include ALL valid data, including that which currently provides evidence for the validity of GR itself.

    None of the fools posting to this or any other forum have come close to meeting this obligation. The typical fool understands nothing of the theory that he crticizes, nor even of the most elementary of physical principles. He refuses to read the literature or standard texts. He is uneducable, and likely quite stupid. Yet he continues to shout that the large scientific community that developed modern cosmology (an army of PhDs and billions of dollars of experimental work) is categorically wrong – and that is the ultimate in arrogance.

    So, fools beware. Either support your position with an adequate, rigorous argument, or be revealed for the fool that you are.


    Addendum: useful references for non-fools (these are NOT popularizations)

    Gravitation -- Misner, Thorne, Wheeler

    Gravitation and cosmology : principles and applications of the general theory of relativity -- Weinberg

    Cosmology -- Weinberg

    General Relativity -- Wald

    Principles of Physical Cosmology -- Peebles

    The large scale structure of space-time -- Hawking and Ellis


     

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  3. #2  
    Veracity Vigilante inow's Avatar
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    Thanks for pulling this together. It will be interesting seeing people get pointed to this as a set of fairly robust information and then continue to ignore it.

    Perhaps this thread can be stickied/pinned?


     

  4. #3  
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    Outstanding!! Thx for the repository. After being spanked by you for being so far behind the curve, I look forward to further annoying you with my misinterpretations.
    - mudbug | 6nqpnw -
     

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    An "extremely compact state" is not what you get when you project the expansion of the universe backwards in time via General Relativity. That's where the horizon and flatness "problems" come from that made the giant band-aid..."inflationary theory"... absolutely necessary to the idea.

    If you did not ***pre-assume*** that there was a singularity, then you would most naturally conclude that a universe with certain pre-existing volume had a big bang, and the horizon/flatness problems then become falsifications of conventional big bang theory from a singularity.

    I'd say that it's more of a case of scientists failing to pay attention to what nature was telling them, and then forcing their foregone conclusion about the singularity through anyway, simply because they could not imagine a mechanism that enables a universe with pre-existing volume to have a big bang. Although... that's exactly what Roger Penrose recently suggested that the empirical data is ONCE AGAIN telling us, so don't be so arrogant as to assume that all reputable physicists buy the hype from a cutting edge that hasn't made a single theoretical advancement in well over thirty years, much less have they fully justified inflation with a complete theory. You obviously have no idea just how agenda driven these guys research results are, but keep reading and you might get a clue...

    And no, you do not need to "replace GR" to derive all of this, this is what GR most naturally derives without pre-assuming something that empiricism does not call for!

    They do not have a reputation for honesty when it comes to this matter and any other that conflicts that empiricism challenges their "consensus" with, regardless of how reputable the dissenting scientists are:

    Lambda/CDM cosmology: how much suppression of credible evidence, and does the model really lead its competitors, using all evidence?
    http://arxiv.org/abs/0705.2462

    From the Alternative Cosmology Group's newsletter:
    http://www.cosmology.info/newsletter/2010.11.pdf

    I. Editorial comment
    The policy changes within arXiv are having the effect they sought. Whilst I haven’t quantified it or made any definitive statistical analysis, it is becoming apparent with each passing month that the LCDM model is used as a filter to exclude what we must assume are ongoing observational results that cast doubt upon the standard approximation in cosmology. Of course, we understand that research follows the money, and the money is always predominantly on models that are being taught at universities. Testing of theories or models for validity has become in most cases simply a matter of checking the formalism for consistency. The principles of Kuhn and Popper are being lost to science, and it is becoming harder by the month to find papers that meet our simple criteria for this newsletter. We have broadened the scope somewhat, but it is nevertheless sobering to look back over the past year and witness the diminishing quantity and quality of challenging observations being published. If it is indeed a trend that cannot be reversed, then we may soon find ourselves trapped in a one-dimensional science classroom.
    Editorial comment
    www.cosmology.info
    ALTERNATIVE COSMOLOGY GROUP


    Oh yeah, and I'm willing to put my money where my "foolish claims" are, or did I meet your criteria for non-fools with a valid point?

    http://www.longbets.org/476
     

  6. #5  
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    Quote Originally Posted by island
    Oh yeah, and I'm willing to put my money where my "foolish claims" are, or did I meet your criteria for non-fools with a valid point?

    http://www.longbets.org/476
    nope
     

  7. #6  
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    Quote Originally Posted by island
    An "extremely compact state" is not what you get when you project the expansion of the universe backwards in time via General Relativity. That's where the horizon and flatness "problems" come from that made the giant band-aid..."inflationary theory"... absolutely necessary to the idea.

    If you did not ***pre-assume*** that there was a singularity, then you would most naturally conclude that a universe with certain pre-existing volume had a big bang, and the horizon/flatness problems then become falsifications of conventional big bang theory from a singularity.
    wrong

    The GR model is based on a homogeneous and isotropic universe, a large scale approximation. Within that restrictive context, there is no "horizon problem". Neither is there a flatness problem.

    The horzon and flatness problems arise when you start to address issues on other than the largest scales. Then one does need something other than just GR, and inflation is the best currently available theory. But inflation does have some problems and is still tentative.

    However, the conclusion that the universe began in an extremely compact form is a solid conclusion from general relativity.

    Nobody is claiming that anything came from a singularity. I know you see such statements in the popularizations, but spacetime cannot have singular points, and singularities in GR are more subtle concepts. In any case the singularity is just a sign that GR has limitations and to understand what was going on in the first fraction of a second we will need better theoretical tools -- probably some version of quantum gravity.

    Nobody has pre-assumed a singularity. In fact the singularity theorems of Hawking and Penrose were surprising when first announced. They are also widely misunderstood, apparently by you as well. Read the papers or the Hawking/Ellis book for details.
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  8. #7  
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    The horzon and flatness problems arise when you start to address issues on other than the largest scales.

    Dude, Georges Lemaître proposed the Big Bang theory in 1927 by projecting expansion backwards to the conclusion that he called his "hypothesis of the primeval atom", so please don't tell me that this wasn't the assumption.

    But you're right, relativity is based on the "cosmological principle". which derives a homogeneous and isotropic universe. Not to mention the principle of relativity...

    And I don't do "popularizations"... I learned what I know from books like "Gravitation" and by discussing what I learned with physicists.
     

  9. #8  
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    This is a great thread, particularly the OP. I've stickied it for now (but leave how long to Dishmaster) in hopes that productive discussion and more informative posts and links can be added.

    Anti-science, pseudoscience, fringe-science, and off-topic posts will be removed. Stickied threads deserve more careful consideration than most, so I'll keep an eye on it.
     

  10. #9 Re: The basis of modern cosmology 
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    Quote Originally Posted by DrRocket
    There seem to be numerous people who come here and post opinions to the effect that mainstream cosmology, in particular the big bang hypothesis, is wrong, offering no rationale other than that is inconsistent with their personal belief, and then take offense when they are told that their characterization of the theory is factually wrong and they don’t know what they are talking about.
    OK try this for size, Time is speeding up, the idea that the cosmos is some 15 billion years old is rubbish. That's my belief, and here's my rationale which, if you can disprove, I'll accept it.

    Given that:

    1) Einstein et al, suggest that placing two identical clocks in two widely differing gravitational environments for any single period, and then bringing the clocks together will show that the clock placed in the lower field (say earth) may show some 5 years has passed where the other (say placed just outside the event horizon of some nearby blackhole may have only advane a few seconds in comparison. (i.e. time dilation as commonly understood).

    Now at present we experience time 'passing' at a specific rate (lets call it x) thus our clock on earth advance at a rate of X.

    2) given that the big bang suggests that the cosmos began as a point of energy/mass or whatever, of infinitesimal size.

    The Hypothesis is;

    As you travel back through time where the cosmos is 'smaller', gravitational density must increase (as per time dilation theory) , thus time will no longer be experienced at rate x. When the cosmos was say the size of our solar system the gravitational forces would/should have been so great that time would pass almost infinitely slowly thus the idea that the universe is 15 billion years old (passing at the rate we experience tod ay) is fundamentally flawed. If you could travel back through time, you may see the big ang ahead BUT you could never actually reach it, thus it is my conjecture that the cosmos is infinite in terms of rate of time experienced thte rate of x, !
     

  11. #10 Re: The basis of modern cosmology 
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    Quote Originally Posted by Home200
    The Hypothesis is;

    As you travel back through time where the cosmos is 'smaller', gravitational density must increase (as per time dilation theory) , thus time will no longer be experienced at rate x. When the cosmos was say the size of our solar system the gravitational forces would/should have been so great that time would pass almost infinitely slowly thus the idea that the universe is 15 billion years old (passing at the rate we experience tod ay) is fundamentally flawed. If you could travel back through time, you may see the big ang ahead BUT you could never actually reach it, thus it is my conjecture that the cosmos is infinite in terms of rate of time experienced thte rate of x, !
    This makes no sense.

    Einstein's general relativity addresses the proper time registered by two clocks with different world lines between two points of intersection of those world lines.

    Your "scenario" treats time as an abstract entity. There is no such thing as a "rate of time". A rste is the chane in something divided by the change in time over the interval in which that something changes. (change in time)/(change in time)=1. Always.
     

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    Of course it's nonsense, the point of the post was to highlight your intolerance to anything other than mainstream. This is a forum presumably for ordinary mortals, if you want it frequented by those who follow rather than thnk, then set the entry conditions a little higher, say ' only those with a PhD in astrophysics may post here'. If you allow all to post here then you should explain in lay terms where a poster might have mis-understood, replying with a one line summary of time dilation shows only that you can relay soemthing written elsewhere, my printer can do that. When posting, may I suggest that as your target audience is the forum, you adopt a style that can be understood by even the least educated (this should be easy for a person of such elevated intelligence). Intelligence is a relative quantity, you can only be intelligent if you are surrounded by non inteligent entities. So make the most of being surrounded by idiots/fools/morons etc.
    "You are only intelligent IF you are surrounded by fools, so don't mock them..." [HOME200]
     

  13. #12  
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    Quote Originally Posted by Home200
    Of course it's nonsense, the point of the post was to highlight your intolerance to anything {other than mainstream} directly rebutted by evidence and which can clearly be seen as false and unrepresentative of reality.
    Corrected.


    Quote Originally Posted by Home200
    This is a forum presumably for ordinary mortals, if you want it frequented by those who follow rather than thnk, then set the entry conditions a little higher, say ' only those with a PhD in astrophysics may post here'. If you allow all to post here then you should explain in lay terms where a poster might have mis-understood, replying with a one line summary of time dilation shows only that you can relay soemthing written elsewhere, my printer can do that.
    It's not anyone else's fault if you haven't spent enough time educating yourself to understand why their replies demonstrate you to be wrong. Instead of bitching that people aren't being treated fairly, I suggest you invest all of this angst and energy into learning WHY they posted the response they did, and try to understand what it means before coming back and making additional silly comments which demonstrate only your personal limitations.

    I'll also give you a nickel's worth of free advise. Your attitude in posting here largely dictates the tone of the response you receive. If you are genuinely curious, and open to the fact that you have a lot to learn... you state that you have some thoughts which you find challenging, and skepticism about the topic that you'd like to delve into more deeply... that you have a thirst for understanding and need some help being pointed in the right direction... the responses are VASTLY more positive than those seen when posters who are clearly ignorant of the subject they're challenging start making broad assertions about its falsehood and have little more than personal "beliefs," misrepresentations, and fabrications from whole cloth to support their position.
     

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    A fountain of knowledge and resources! Thanks a ton OP! I appreciate it.
     

  15. #14 Re: The basis of modern cosmology 
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    Quote Originally Posted by Home200
    The Hypothesis is;

    As you travel back through time where the cosmos is 'smaller', gravitational density must increase (as per time dilation theory) , thus time will no longer be experienced at rate x. When the cosmos was say the size of our solar system the gravitational forces would/should have been so great that time would pass almost infinitely slowly thus the idea that the universe is 15 billion years old (passing at the rate we experience tod ay) is fundamentally flawed. If you could travel back through time, you may see the big ang ahead BUT you could never actually reach it, thus it is my conjecture that the cosmos is infinite in terms of rate of time experienced thte rate of x, !
    As I understand the theory, expanding space doesn't necessarily obey General or Special Relativity. All that matter in one place would bring a clock to a stop, but then expanding space could still carry that stopped clock away. In reality, what you're really predicting is that the initial stages of expansion would have seemed even faster to a local observer than they are predicted to have been in our present frame of reference.


    However.... there is one other thing you are missing. If the universe was continuous in the way the surface of the Earth is continuous, where if you travel all the way around it in a straight, and carefully chosen line, you may end up where you began (only try to imagine that with 3D space acting like the 2D surface of the Earth), then every object in space would perceive equal amounts of mass to be located on all sides of it, which cancels out to leave a zero net gravitational field. (Just think of the gravitational field in the center of a uniform spherical shell.)
    Some clocks are only right twice a day, but they are still right when they are right.
     

  16. #15  
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    I just thought that the following link might fit in this thread:
    Frequently Asked Questions in Cosmology
     

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    Admit that DrRocket has some valid points. But other valid points have been made. There is something called modern medicine too. Then, there is "alternative" medicine. Many of the therapies of alternative medicine really work. Many of the therapies of alternative cosmology really work too.

    Alan Guth made a giant contribution to modern cosmology. Singularities as point masses are cental to "inflation-like" solutions to the flatness and horizon problems which had vexed astrophysicists for years prior to Guth. If these paradoxes had been so simple that they could have been dismissed in a few sentences, they would have been. There have been numerous attempts to refine Guth's inflation but the original formulation still stands the test of time, so far.

    It is not as if there is no precident for singularities. Point masses and point charges are common in quantum mechanics. Guth's proposal implies that the universe was a quantum object, that is all. If it was a quantum entity in the past, then it still is. Then, all of the conundrums of quantum theory will apply to it. Shall we apply the Copenhagen Convention or shall we apply the Many Worlds Interpretation? Should we consider that there could be a quantum universe, an anti-universe and interference universes all superposed to make a total global universe that satisfies the missing mass problem? This would solve certain other problems with the "Standard Model".

    Black hole singularities are extrapolations from general relativity (GR) that are not "renormalizable" and resist easy quantization except to use the Schroedinger tactic of simply assuming them as postulates. Yes, there are difficulties imaginng what happens when matter falls into a black hole toward the center of mass when time must slow to as near zero as one may like. This is the meaning of the phrase "tends to infinity". It means only that the quantity may be considered to be as close to infinitely large or small as one may need for any given purpose.

    The profile of an infinitely deep gravitational field potential (in a 2D plot, for instance) is represented by an hyperbola having the abscissa as an asymptote. It is as easy to graph as a parabola that has no asymptote. The graphical parabolic gravitational potential is a representation of Newton's Law of Gravity. The hyperbolic gravitational potential results from relativistic consideration of black holes. The black hole singularity is part and parcel of GR. To rule them out, one must rule out GR. Singularities (and infinities) are distasteful to mathematicians because little more can be done with them - they are mathematical dead ends. But, Schwartzchild and others found that such singularities must be real. And, considering that black holes must have non-Newtonian hyperbolic gravitational fields, certain problems, conundrums or paradoxes of modern cosmology disappear without the invention of ad hoc Dark Energy or Dark Matter.
    Last edited by Gary Anthony Kent; September 7th, 2011 at 04:03 PM.
     

  18. #17  
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    Quote Originally Posted by Gary Anthony Kent View Post
    Admit that DrRocket has some valid points. But other valid points have been made. There is something called modern medicine too. Then, there is "alternative" medicine. Many of the therapies of alternative medicine really work. Many of the therapies of alternative cosmology really work too.
    And it is just as nuts to believe these alternative cosmologies as it is to believe in alternative medicine.
     

  19. #18  
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    Quote Originally Posted by Gary Anthony Kent View Post
    There is something called modern medicine too. Then, there is "alternative" medicine. Many of the therapies of alternative medicine really work.
    There's no such thing as "alternative medicine." Alternative almost by definition means it does not work, and if it works we would use it. Do you know what they call alternative medicine that's been proven to work? They call it "medicine."

    With your alternative cosmologies, we begin with the belief that these things don't work until valid evidence has been provided to show that they do. It's really that simple.
     

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    Quote Originally Posted by DrRocket View Post
    There seem to be numerous people who come here and post opinions to the effect that mainstream cosmology, in particular the big bang hypothesis, is wrong, offering no rationale other than that is inconsistent with their personal belief, and then take offense when they are told that their characterization of the theory is factually wrong and they don’t know what they are talking about. They criticize their critic as arrogant.

    The true misplaced arrogance lies with the poster who presumes on the basis of his so-called “common sense” that the work of an army of dedicated physicists based on over a century of theoretical, experimental and observational work, and not a few Nobel Prizes, is wrong. In the meantime the OP, hereafter known as “the fool”, misrepresents the mainstream theory, which he understands not at all, and makes criticisms that violate principles that have been well-established since the eighteenth century and are known to high-school students. The fool fails to understand that he does not understand, but is unwavering in his opposition to a theory about which he is clueless.

    These people should have to pay for air.

    Make no mistake, the modern theory of cosmology is a work in progress. But it is a work with a solid foundation.

    The pillar of modern cosmology is one of the pillars of modern physics, general relativity.

    General relativity (GR) was formulated by Albert Einstein and announced in 1915. It has since received a great deal of attention, the mathematical foundations have been examined, the presentation refined, and a host of confirming experiments performed. General relativity, with its mathematical roots in Riemannian geometry is a formidable subject, and some of its predictions are contrary to everyday experience – i.e. “common sense” can be badly mistaken. That is no surprise as even special relativity, the precursor and “little brother’ of GR is surprising at first encounter.

    gr
    Introduction to general relativity - Wikipedia, the free encyclopedia
    General relativity - Wikipedia, the free encyclopedia
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    GR treats the universe over all time as a single entity – spacetime. This can also be done in Newtonian mechanics, so there is nothing really new about spacetime. What distinguishes GR is that spacetime is not just affine 4-space, but in fact is a Lorentzian 4-manifold of undetermined topology, with a curvature tensor that is also unknown but is determined by the distribution of mass/energy via a stress-energy tensor defined by a very complex set of partial differential equations. These equations, the Einstein field equations can only be explicitly solved in a few simple circumstances. Gravity is the result of curvature of spacetime.

    In general because of curvature neither space nor time have any global meaning. However, if one makes the assumption that spacetime is homogeneous and isotropic, then spacetime decomposes as a 1-parameter foliation by space-like 3-dimensional hyperplanes of constant curvature. The parameter serves as a surrogate for time and the hyperplanes as a surrogate for space. The hyperplanes inherit a true Riemannian metric from spacetime and expansion of space means that the distance between points increases as the value of the time-like parameter increases.

    Astronomical observations support the assumption that the universe is homogeneous and isotropic on the largest scales. Observations also support the expansion of space.

    Hubble Constant -- from Eric Weisstein's World of Physics
    https://www.cfa.harvard.edu/~huchra/hubble/
    WMAP- Expansion of the Universe
    Wilkinson Microwave Anisotropy Probe (WMAP)
    Wilkinson Microwave Anisotropy Probe - Wikipedia, the free encyclopedia
    http://aether.lbl.gov/www/science/cmb.html
    http://aether.lbl.gov/www/science/cmb.html

    Based on these assumptions and observations Hawking and Penrose in a series of papers used general relativity to conclude that, as a logical consequence, the universe began in an extremely compact form, and in fact predicted singular behavior (which is generally thought to indicate a limitation of general relativity to predict the first fraction of a second)

    03.16.2007 - Origins of the universe: Stephen Hawking's J. Robert Oppenheimer Lecture
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    The Singularities of Gravitational Collapse and Cosmology

    So, while nobody knows what happened in the first fraction of a second, the big bang hypothesis in terms of subsequent expansion from an extremely compact state is on firm empirical and theoretical grounds.

    Inflation is not necessary to the big bang, but does use ideas from quantum field theory to explain why the universe is homogeneous on the large scale, yet exhibits anisotropy on smaller scales. It is not a fully verified, or even rigorously formulated, theory, yet. It is promising. It is supported by what has been seen in surveys of the cosmic background radiation. Attacking inflation as unproven is futile, because it is well-known to be just that. But interpreting “unproven” as fanciful or unlikely is simply a demonstration of ignorance.

    http://web.mit.edu/physics/news/phys..._cosmology.pdf

    Thus, modern cosmology rests on a solid foundation of empirical data and well-formulated theory. That does not make it immutable. Any physical theory is subject to refinement and extension. But any revision must meet equal standards of rigor.

    The fool who rejects modern cosmology must meet the obligation of providing the basis for an alternative . That means providing a theory of gravity to replace GR, and the empirical data to support it. Further, that data must include ALL valid data, including that which currently provides evidence for the validity of GR itself.

    None of the fools posting to this or any other forum have come close to meeting this obligation. The typical fool understands nothing of the theory that he crticizes, nor even of the most elementary of physical principles. He refuses to read the literature or standard texts. He is uneducable, and likely quite stupid. Yet he continues to shout that the large scientific community that developed modern cosmology (an army of PhDs and billions of dollars of experimental work) is categorically wrong – and that is the ultimate in arrogance.

    So, fools beware. Either support your position with an adequate, rigorous argument, or be revealed for the fool that you are.


    Addendum: useful references for non-fools (these are NOT popularizations)

    Gravitation -- Misner, Thorne, Wheeler

    Gravitation and cosmology : principles and applications of the general theory of relativity -- Weinberg

    Cosmology -- Weinberg

    General Relativity -- Wald

    Principles of Physical Cosmology -- Peebles

    The large scale structure of space-time -- Hawking and Ellis

    A good resource. Reference lists with annotation are invaluable.
     

  21. #20  
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    Quote Originally Posted by physbang View Post
    Quote Originally Posted by gary anthony kent View Post
    admit that drrocket has some valid points. But other valid points have been made. There is something called modern medicine too. Then, there is "alternative" medicine. Many of the therapies of alternative medicine really work. Many of the therapies of alternative cosmology really work too.
    and it is just as nuts to believe these alternative cosmologies as it is to believe in alternative medicine.
    ignore semantics
     

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    Quote Originally Posted by inow View Post
    Quote Originally Posted by gary anthony kent View Post
    there is something called modern medicine too. Then, there is "alternative" medicine. Many of the therapies of alternative medicine really work.
    there's no such thing as "alternative medicine." alternative almost by definition means it does not work, and if it works we would use it. Do you know what they call alternative medicine that's been proven to work? They call it "medicine."

    with your alternative cosmologies, we begin with the belief that these things don't work until valid evidence has been provided to show that they do. It's really that simple.
    ignore semantics - again
     

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    Quote Originally Posted by Home200 View Post
    Quote Originally Posted by DrRocket
    There seem to be numerous people who come here and post opinions to the effect that mainstream cosmology, in particular the big bang hypothesis, is wrong, offering no rationale other than that is inconsistent with their personal belief, and then take offense when they are told that their characterization of the theory is factually wrong and they don’t know what they are talking about.
    OK try this for size, Time is speeding up, the idea that the cosmos is some 15 billion years old is rubbish. That's my belief, and here's my rationale which, if you can disprove, I'll accept it.

    Given that:

    1) Einstein et al, suggest that placing two identical clocks in two widely differing gravitational environments for any single period, and then bringing the clocks together will show that the clock placed in the lower field (say earth) may show some 5 years has passed where the other (say placed just outside the event horizon of some nearby blackhole may have only advane a few seconds in comparison. (i.e. time dilation as commonly understood).

    Now at present we experience time 'passing' at a specific rate (lets call it x) thus our clock on earth advance at a rate of X.

    2) given that the big bang suggests that the cosmos began as a point of energy/mass or whatever, of infinitesimal size.

    The Hypothesis is;

    As you travel back through time where the cosmos is 'smaller', gravitational density must increase (as per time dilation theory) , thus time will no longer be experienced at rate x. When the cosmos was say the size of our solar system the gravitational forces would/should have been so great that time would pass almost infinitely slowly thus the idea that the universe is 15 billion years old (passing at the rate we experience tod ay) is fundamentally flawed. If you could travel back through time, you may see the big ang ahead BUT you could never actually reach it, thus it is my conjecture that the cosmos is infinite in terms of rate of time experienced thte rate of x, !
    Only measurable cosmological objects and phenomena contribute to estimates of the age of the universe. By these hard measurements that have all occurred in our own standard time, the extrapolation of events backward in time, according to Hubble's Law and its corollaries, gives just as hard a result. Oh yes, interpretation of red-shifts requires use of a model to flesh out the simple math of certain relativistic equations with actual numbers that are corrected to account for past curvature of space that existed and extra curvature that existed due to changing gravitational field density. But, even with uncorrected numbers the universe's age works out to at least 15 or 16 billion years. One needs to use "the standard model", or some other device like it, only to get the age exact and precise at 14.72 billion years.

    Those who make fundamental criticisms have to provide even more fundamental and decisive facts to back themselves up. Nobody has to disprove any of your observations. YOU have to prove them to be true, relevant and factual. If you can do a better job than Einstein and at least 50 other top caliber workers in this area since 1915, lets us see your formal research paper in Science or Nature.
    Last edited by Gary Anthony Kent; September 13th, 2011 at 07:15 AM.
     

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    By the way, I am back with my old persona. I was getting nasty e-mail and spam from the misuse of my personal info given in my profile. So I "retired" G.A.K. and registered another persona that I named simply "Kent", with goofy profile info. I also had crippling problems logging-in using G.A.K. So, I had no choice. But, now that these problems are solved - except to respond to Kent's posts that I already made - I will retire him until some other snafu flattens me. Be assured, neither Kent nor G.A.K. are sock-puppets designed to subvert the forum. I will never use them simultaneously or alternately to bust ethics rules.
     

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    When science becomes sacred, must not forums defer to sessions of guided chanting? Carl Sagan's baloney detection kit returns a fresh breath of air to those whom Dr. Rocket begrudges such ventilation. Who are any of us, to disagree?
    "Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense." --Buddha (563BC-483BC)
     

  26. #25  
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    Quote Originally Posted by DrRocket View Post
    There seem to be numerous people who come here and post opinions to the effect that mainstream cosmology, in particular the big bang hypothesis, is wrong,offering no rationale other than that is inconsistent with their personal belief, and then take offense when they are told that their characterization of the theory is factually wrong and they don’t know what they are talking about. They criticize their critic as arrogant.
    the BB, the (big bang or) birth of being, that is : cosmogony, genesis, creation of the world. The most intriguing and inscrutable mystery

    The hypothesis 'de l'atome primitif' (called in a semi-derogatory way "bigbang") was not new, original, as a matter of fact it is over 4000 years old: it's the Hindu myth of the expanding universe (=egg) BrahmAnda. The author probably referred to it when he described his theory "the cosmic egg exploding at.. creation".
    Hindu wisemen extended the myth to the more logical, natural cycle of BrahmandaPurana, (= bigbounce). It is a plausible theory, coherent, logical because it is founded on analogy, it is not scientific because it gives no explanation.
    So, nothing new under the sun! 4200 years before Hubble, Indian philosophers knew the universe is expanding, what's the big surprise of BB?
    The key point of any cosmogonic theory is the beginning, the cause: there is no possible explanation of the starting point, both in creation ex nihilo and in creation by transformation. Science criticizes myth (and religion), because they are dogmatic, give no explanation, but...
    what does science offer better, more scientific than myth : "in the beginning was (the cosmic egg):a super-supermassive black hole a singularity, now it is here there and everywhere". Is this reductive?, prove it!

    1)
    The key point is the detailed, logical explanation of the cause and the ways of the explosion:
    [(only re: cyclic model) where BH comes from, how it was formed, how long it existed before exploding,] (BB size of universe, space and time, properties of BH: size, mass, temperature... etc..., why it exploded, how much energy is necessary, where this energy comes from, how long the explosion lasts, properties of the particle expelled, if all matter was shot out how this is possible, the speed and direction of the particles... etc....
    at least a dozen answers are required for the foundation of a plausible hypothesis, answers must not break (no ad hoc exceptions, no informal fallacies) any of the valid experimented laws of physics, else you [when I say you it is not personal, you (or any-member-of-the-FORUM) as spokesman of cosmogonists] are regressing to myth and superstition.

    Stricly speaking you are trespassing, the issue is not even within the jurisdiction of science, as it is a one-off event.
    Science babbles about 1), and the feeble babble is often againstthemainstream ATM, a string of fallacies and absurdities, that violate the laws of physics and logic.
    I challenge your theory not because it is inconsistent with my belief, but because it is inconsistent with mainstream.

    Answer 1, put numbers from 1 to 15, (if you do not know the answer, just say so) and then I'll present further arguments.




    Last edited by ray; September 20th, 2011 at 02:42 AM.
     

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    Okay, this thread is not meant to debate the individual ideas and pet theories of every one of you. Open a new thread for this in "New Theories". This thread is meant as a source of information about the current understanding of that field of research. Therefore, I close this thread.

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