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They are one and the same, and the opposing model is the Cold Big Bang. Cold big bang is a designation used in cosmology to denote an absolute zero temperature at the beginning of the Universe, instead of a (hot) Big Bang. Also see the Big Bang page of wiki, it also has clues to why it may be called hot. Cold Big Bang


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We have, at this time, no tools capable of detecting neutrinos at the very low energies of the cosmic neutrino background, and if such tools existed they would have to contend with numerous backgrounds making the experiment ferociously difficult.


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There is a very nice paper exactly on this topic, where the expressions describing the fit curves are derived: http://arxiv.org/abs/hep-ph/9906447v1 If you have a look at the final expression (formula (6.5) on page 8), you will agree, that the relation between $\Omega_\Lambda$ and the luminosity is hard to describe by words. However, you can try to think ...


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First of all, we still do not know if the 4 fundamentals forces can be unified. The best we have came up to are GUT theories, which join three of the fundamental forces except gravity. The fact that gravitational waves have been detected, may point towards GUT since they address energies of the GUT scale. Nonetheless, assuming that String theory, which is ...


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Nope, gravitational waves were predicted by Einstein's General Relativity theory which is a very successful theory of gravity. We still though do not have a working theory of Quantum Gravity and cannot therefore unify these forces as of yet.


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Leptons annihilate to photons. Hadrons (quarks, 99.97 mass-% of matter) emit about 50% of ${mc^2}$ annihilation energy as neutrinos. If the Big Bang plus cosmic inflation had exactly obeyed all current conservation laws, everything would have exactly cancelled to photons and neutrinos. Pair formation must be antisymmetric re conservation laws, offering no ...


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The key bit of your question is: why isn't it possible all original matter and anti-matter annihilated each other leaving all pure energy, which in turn and in time could form into matter? since other parts of it are covered by the question Parth Vader linked. Matter and anti-matter don't annihilate to produce pure energy, they annihilate to produce ...


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Energy equals mass multiplied by the speed of light squared, and mass equals energy divided by the speed of light squared. What goes up, must come down. Nothing can escape a black hole. Every action has an equal and opposite reaction. Energy cannot be created or destroyed, it only changes form. All things in an enclosed system gain entropy, slow down, ...


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The simplest idea is that the collapse of the previous universe caused the big bang. I imagine it as black holes smashing into each other at great speed, immediately causing a nuclear reaction. There are some unproven theories that need to be adjusted, such as the idea that dark energy density remains constant as space expands. Black hole radiation has ...


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There are several scenarios that point out cyclic cosmologies. The first one is called Matter bounce cosmology which is based on the idea that that the universe originated from a cosmological bounce in which quantum fluctuations develop into a scale-invariant spectrum of curvature perturbations. The bounce is realized beyond Einstein's General Relativity and ...


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I'm not sure exactly what you're referring to as the three different theories, but recollapsing, accelerating and anything in between universes are not different theories. They are all examples of a solution to the equations of general relativity called the FLRW metric. If we make a few physically plausible assumptions about the distribution of matter in ...


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The dividing line meets at $(\Omega_m,\Omega_\Lambda)=(0,1)$. From the Friedmann equations, it follows that the scale factor $a(t)$ satisfies the relation $$ \frac{\dot{a}^2}{H_0^2} = \Omega_m a^{-1} + (1 - \Omega_m - \Omega_\Lambda) + \Omega_\Lambda a^2. $$ The universe has no big bang singularity if the above expression is negative (or zero) for some ...


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There is a central point, the point that is the opposite to the expansion of the sphere. We can't see it, but I would assume that in a similar way to how when large stars go supernova they leave behind a black hole, and how there are black holes in the middle of galaxies, there would probably be a black hole in the centre. We would never see it, because ...


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There are a few other reasons why we think the universe is expanding. Wikipedia lists and explains them far better than I will ever be able to. One thing though, your ruler is not expanding. The intermolecular forces are making sure the distance between molecules stays the same. Empty space is expanding, expanding essentially the distances between weakly ...


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Remember, the Big Bang theory is just that- a theory. I predict astrophysicists will soon discover galaxies 15,20,25, billion years old. Then what?


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There exists a huge gap in the strength of the four forces that we have observed in nature between gravity and the other three: In the following image we see that the radiation decouples from the "soup" at energy densities of 0.25eV. That is the snapshot of CMB, Cosmic Microwave Background radiation . CBR in this plot is the CMB, when we have a ...


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Carbon has to be produced by the triple-alpha process because there is no stable nucleus with 8 or 5 nucleons. The probability of this is very low, because it requires three different particles to be in the same place at the same time. You'll note that the Wikipedia article says: One consequence of this is that no significant amount of carbon was ...


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Well, the argument is something like this. Matter and radiation are tightly coupled until the time of last scattering. The photons are in thermal equilibrium with the plasma surrounding them. This means the state of the Universe at the time of last scattering is very precisely imprinted on the photons, and the photons travel from last scattering to us more ...


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You've overlooked gravitational entropy. The entropy of a black hole horizon is given by: $$ S = \frac{kA}{4 \ell_p^2} $$ where $A$ is the area of the horizon, $k$ is Boltzmann's constant and $\ell_p$ is Planck's constant. This entropy is absolutely huge, so if you take a uniformly distributed gas in thermal equilibrium and concentrate it into a black ...


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Besides the comments, stars have formed well after the Big Bang. Depending on where they are in the universe, it will take a while for us to see them.


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The time used in describing the evolution of the universe is comoving time. This is the time that would be measured by a freely moving observer on their wristwatch (assuming the high temperatures didn't melt both the observer and the wristwatch :-). Time is not a simple thing to define in general relativity, however we can always unambiguously define proper ...


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This is a common point of confusion, not only with regards to inflation, but any time an expanding universe comes up... The "cosmic speed limit" as you call it says that no particle or signal can move through spacetime faster than the speed of light. Spacetime is a very specifically defined thing, described with a coordinate system. There is no restriction, ...


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I think that dark matter disproves the big bang. The energy excerpted by dark matter on all things would have prevented the universe from coming into existence through the big bag.


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In curved spacetime, you can no longer compare velocities at different points in the straight-forward manner we use in flat spacetime. Thus the claim that recession velocities should not be considerer 'real' (as in relative) velocities, but rather rates of expansion of space. If you want to get at the former, you need to parallel transport the source's ...


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After the Universe became transparent to electromagnetic waves, the first wave produced from whole mass lump was Cosmic Microwave Background (CMB) radiation which we can still receive from farthest point of the observable universe (CMB causes your radio to hiss on blank stations). Universe has expanded since then, so CMB is still running trapped inside ...



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