A brief History of... Astrophysics

Discussion in 'Physics & Math' started by Reiku, Mar 6, 2008.

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  1. Reiku Banned Banned

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    The Big Bang merit's quite a few problems actually. Also known as the standard cosmological model, it predicts the big bang nucleosynthesis, which measures the correct elements thought to pervade the universe. It also wipes out initial start-up conditions, through inflation. And inflation itself, points to a flat universe, and this compliments the observations on background microwaves made by the Wilkinson Anisotropy Probe (1).

    The theory of the big bang was created in 1930 by a Belgian astronomer, Georges Lemaitre. He described the universe to have came into existence around 10,000 million years ago - (today, inflation has added an extra 5,000 million years to this count - and he said that all of matter was contained in a ''primal atom'' (which Stephan Hawkings today exactly explains through his quantum cosmological theory), which Lemaitre called a super dense ''cosmic egg.'' (2)

    Critics of the big bang theory go back many years, including Lerner and Einstein... Fred Hoyle is also known for his anti-big bang attacks. It is a little ironic that Hoyle would go onto be the coiner of the term, 'big bang.' Thus, Hoyle approached the problem of big bang mathematically, and decided to bring in a new theory, called the 'steady-state theory,' or the 'continuous theory;' two other supporters at the time working alongside Hoyle in 1948 was Hermann Bondi and Thomas Gold.

    In the standard cosmological model (big bang), the universe poured out from a single point, where space just began, and if we take relativity seriously here, this must also mean time; thus space cannot begin an existence, without time dragging along with it. But this is not so in steady-state theory. Instead, it opts. that space has no beginning, and thus this must also mean time. In this picture, the most accepted nature of the universe is said to be expanding, and we tend not to say the universe is contracting or static.

    How do we know the universe is not static?
    The answer to this question is solved in 'Olber's Paradox,' stating we know this because the sky is dark at night. The importance of this premise is that light would be trapped in a static universe, and it would slowly illuminate the universe. And it would do us no good to say the universe is contracting, because our universe is now suspected to be accelerating in its expansion.
    Hoyle's theory proposes that the density of the universe decreases with expansion is ''balanced'' wiith the continuous creation of matter forming into entire galaxies that replace spaces between receding galaxies. The matter, if you where wondering, is created from a negative energy reservoir; the reason why this energy needs to be negative, is to assure that no dilution of the source occurs.

    It also predicts that helium and hydrogen is produced inside supernovae... as you might know, the big bang states that these elements would have been created at the very start of spacetime expansion. Hoyle also discovered how carbon is formed inside of stars, through a special nuclear process involving three alpha-particles, made up themselves of two protons and two neutrons.

    Other theorists have come together to answer the big bang paradox. One major problem, is that in the standard model, nothing caused big bang; it just simply happened without cause. Paul Steinhardt of Princeton University and Neil Turok of Cambridge, have proposed the 'Ekpyrotic Cosmological Theory' to answer the original cause of the big bang.
    The theory itself states that 15 billion years ago, big bang was just a marker in time; it turns out that the universe is much older - guesse is, if the Ekpyrotic theory is correct, then the universe existed for eons before big bang - possibly for trillions of years. Before big bang, our universe is said to have been in a frozen state. Then, guided by a primordial force, another brane (2) smacks into our universe, creating a sea of electrons, protons, neutrons and quarks.

    This theoretical explanation to cosmology, first proposed at a cosmology meeting at the Space Telescope Science Institute in Baltimore, describes an alternative to big bang theory coupled with inflation, which is a point when the universe required to expand faster-than-light. Whilst many scientists find the theory a challenging proposal against big bang, other scientists believe the Ekpyrotic theory to be somewhat something of a dream, a fantasy of sorts. If you think of it though, big bang is more of a fantasy, because big bang occurred without any precursor. Viola! The mystical just happened.

    In this theory, our universe is a brother to many other universes, floating about in a void of nothingness. The makers of Ekpyrotic theory use, not the conventional 11 dimensions of M-Theory, but rather specificities these brother universes as moving through the fifth dimension. By allowing these universes to flow through the fifth dimension (4), answers why they can never by visible, simply because light cannot travel through the fifth dimension. Howsoever, gravity can couple to other universes, and it is for this reason, all universes are said to form one giant superstring (5), floating around in a void of nothingness (6).

    Ekpyrotic theory is not the first complicated theory to presume the universe has cycles. In 1965, American astronomer Professor Allan Sandage adapted the big bang theory, and developed the 'pulsating universe theory,' or (PUT). He believed that the universe expanded and then contracted; a cycle that continues forever. He hypothesized that the expansion and contraction of the universe took 80,000 million years. This kind of theory doesn't really say that the universe has an infinite lifetime, but rather an infinite amount of beginnings and ends.

    Since we cannot ever observe how the universe began, we cannot really make assured predictions of it. All we can do is make educated assumptions on how the beginning may have prevailed through observing today's initial condition. We are however, by no means closer to cracking the mystery of how our universe began, or didn't (as the case may be), using the steady-state theory, big bang theory or Ekpyrotic theory.

    Notes

    (1) - Nuclear Fusion is the process in which multiple particles join to make heavier nuclei.

    (2) - This would be within a Planck Density, given as D_pi=√(Gh/c^2.2) > pr accurately in short notion: 10^93.

    (3) –Which is just another term for a universe

    (4) -Which is an electromagnetic potential which directly effects all electromagnetic materials.

    (5) -Which would seem to suggest that the geometrical fugure of the universe would be cylindrical, 8πG/c4, instead of flat w-1

    (6) -And the univese cannot be known after this point. Before this point, physics is disabled. The only viable, yet highly controversial idea is that there was a universe that existed Pre-Planck scale... but hey... it seems increadible, but not improbable.
     
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  3. James R Just this guy, you know? Staff Member

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