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Cosmology: the scinece on the universe.

  1. Jun 23, 2005 #1
    Hi, everybody,
    I am planning to write an article titled "cosmology: the scinece on the universe".
    So far I have written about 40 pages. I want to share/check
    my ideas with you. Abstract of the article looks as follows:

    Every object in the universe, living or non living, changes with time
    and it makes sense to talk about its birth and death. Modern scientific
    theories tell us how stars and planets form, how galaxies cluster, how
    life originates on the Earth, but the question of how the universe came into
    being is difficult to address. This is because unlike other
    objects, we have a single universe and the problem becomes further complicated
    by the fact that we are also part of the universe so there is no way
    to study the universe objectively. We do not have multiple copies of the
    universe to perform experiments; nor does our life period compare with the
    physical process of cosmic importance. This puts strong constraints on
    our understanding of the universe. Unlike other sciences which
    fragment knowledge into parts, in order to make a complete picture of
    the universe, in cosmology we put bits and pieces of various kinds of
    knowledge together and this makes the job of cosmology very difficult.
    We have experienced that physics which (classical mechanics) works very well
    in our daily life (length scale, say 1 cm) fails badly at atomic scales
    ($ \approx 10^{-8}$ cm) and we need quantum corrections. In spite of this,
    in cosmology we stretch physics which has been tested at far below galactic
    scales ($ \approx 10^{14}$ cm) to cosmological scales ($ \approx 10^{28}$ cm).
    This puts a question mark on the reliability of modern cosmology.
    Nevertheless, in the absence of any other option we do this extrapolation and
    draw a picture of the large scale structure of the universe. One can always
    ask: why do we need to study the universe as a whole ? Because what matters
    to us is, what is in our neighborhood. However, this is not true. There are
    many cosmological consequences which we observe in our life. Apart from
    cosmological events, what else can produce this copious amount of hydrogen,
    helium, lithium and other light elements which we observe in the universe. We
    do not know what else apart from the early universe, which was supposed to be
    in thermal equlibrium at very high temperature, could produce the radiation
    (CMBR) which we receive equally from all directions. It is far from a
    coincidence that life, which we know, has not been here billions of years ago.
    This is because this form of life needs higher elements and it takes billions
    of years to synthesize these deep in the core of stars. There are many reasons
    to believe that the universe does evolve in time. Now one of the big questions
    is: does the universe also follow the same destiny which is followed by other
    objects in it i.e., cycle of birth and death. This idea is not very new.
    Plato proposed a long time back that the universe is analogous to a gigantic
    living being. We know birth and death are nothing but some kinds of changes
    which take place in physical objects in the universe. Will this logic work
    with the universe ? Yes, but for that we will need a bigger universe or
    multiverse which can accommodate our universe. I think it will never be
    possible to answer questions like the birth and death of the universe. In this
    article we will mostly forget about the birth and death of the universe and
    will focus mainly on what happens in the life of the universe. We will be
    mainly concerned about that part of space-time which is accessible to us or
    which we can probe with our physical devices. There are many mysteries in the
    universe: what is dark matter and dark energy ? Does general theory of
    relativity work on cosmological scales ? How to explain the big bang ? How the
    universe will end ? Why are physical parameters in the universe fine tuned ?
    In order to answer these and many such questions, there have been proposed
    many new concepts like the concepts of extra dimensions, scalar fields,
    tachyons, supersymmetry etc.
    We hope many of these concepts will be verified in the near future.
    We do not have a consistent theory of quantum gravity
    which we believe will solve many puzzles of the universe. Cosmology is the
    science of the universe and the universe includes everything and this puts
    limitations on our understanding of the universe, so certain aspects of
    cosmology are not science at all ! This article is mainly concerned about
    those aspects of the universe which can be explained on the basis of the
    known laws of physics. However, we will not stop ourself from discussing
    sceptical ideas also.

    ... to be continue
  2. jcsd
  3. Jun 24, 2005 #2


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    Staff Emeritus
    Science Advisor
    Gold Member

    There isn't a particularly well supported theory for that one (biogenesis). The Theory of Evolution pertains to changes after the beginning of life, not the beginning itself.

    I don't follow. This seems to be an important statement to clarify.

    perhaps you mean "speculative" ideas?
  4. Jun 24, 2005 #3
    I didn't read all of it but there are a number of comas missing. Just a friendly hint to check the punctuation. :smile:

    The Bob (2004 ©)
  5. Jun 25, 2005 #4
    I mean how various complex chemicals like proteins etc.,
    synthesize from simple chemical elements, and how how the
    life become complex with time. My point is just to say that we a theory of biological evolution, which is quite

    Since the universe includes observer also so in order to
    understand a physical process, we need to konw the observer (consiousness) also. This line of reasoning goes
    with, what we call "observer selection effect" or "anthropic principle".

    that is right.
  6. Jun 25, 2005 #5


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    Science Advisor
    Gold Member

    The abstract is too long and detailed. Abstracts should be crisp, brief and pointed.
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