This link has been bookmarked by 68 people . It was first bookmarked on 15 Jul 2006, by gbrisdon.
-
21 Jun 15
-
28 Jan 15
-
22 Jan 15
-
24 Nov 14
heatherpizzolato" Consequently, the universe was denser and hotter in the past. Moreover, the Big Bang model suggests that at some moment all of space was contained in a single point, which is considered the beginning of the universe. Modern measurements place this moment at approximately 13.8 billion years ago, which is thus considered the age of the universe.[2] After the initial expansion, the universe cooled sufficiently to allow the formation of subatomic particles, including protons, neutrons, and electrons. Though simple atomic nuclei formed within the first three minutes after the Big Bang, thousands of years passed before the first electrically neutral atoms formed. The majority of atoms produced by the Big Bang were hydrogen, along with helium and traces of lithium. Giant clouds of these primordial elements later coalesced through gravity to form stars and galaxies, and the heavier elements were synthesized either within stars or during supernovae."
-
06 Jul 14
ralawamiKey idea is that the universe is EXPANDING
All matter was contained in a single point
Hydrogen, helium and lithium were formed at first
COALESCED through gravity
forming stars and galaxies
Heavier elements synthesised through the supernovas and within the stars
COSMIC MICROWAVE BACKGROUND
Hubble's law
Relying on General Relativity
universe 13.8 billion years old
Random motion of particles at relativistic speeds
D is the comoving distance
universe looks the same in all directions
Abundance of PRIOMORDIAL ELEMENTS
he-4, he-3 and li-7 to the amount of hydrogen
Energy density decreases with expansion
73 p dark energy and 23 p dark matter
1 p neutrinos
Universe remains close to flat
OMEGA COSMOLIGCAL PARAMETER -
28 Feb 14
-
-
As the distance between galaxies increases today, in the past galaxies were closer together. The consequence of this is that the characteristics of the universe can be calculated in detail back in time to extreme densities and temperatures,[12][1
-
he only remaining interpretation is that all observable regions of the universe are receding from each other.
-
and yet the universe today remains very close to flat
-
-
30 Jan 14
-
02 Aug 13
-
The Big Bang theory is the prevailing cosmological model that describes the early development of the Universe.[1] According to the theory, the Big Bang occurred approximately 13.798 ± 0.037 billion years ago,[2][3][4][5][6][7] which is thus considered the age of the universe.
-
-
10 Jun 13
-
The Big Bang is a well-tested scientific theory and is widely accepted within the scientific community. It offers a comprehensive explanation for a broad range of observed phenomena, including the abundance of light elements, the cosmic microwave background, large scale structure, and the Hubble diagram for Type Ia supernovae.[12] The core ideas of the Big Bang—the expansion, the early hot state, the formation of helium, and the formation of galaxies—are derived from these and other observations that are independent of any cosmological model. As the distance between galaxy clusters is increasing today, it is inferred that everything was closer together in the past. This idea has been considered in detail back in time to extreme densities and temperatures,[13][14][15] and large particle accelerators have been built to experiment in such conditions, resulting in further development of the model. On the other hand, these accelerators have limited capabilities to probe into such high energy regimes. There is little evidence regarding the absolute earliest instant of the expansion. Thus, the Big Bang theory cannot and does not provide any explanation for such an initial condition; rather, it describes and explains the general evolution of the
-
-
10 Feb 13
-
11 Dec 12
-
16 Sep 12
-
the Universe cooled sufficiently to allow energy to be converted into various subatomic particles, including protons, neutrons, and electrons.
-
The Big Bang is a well-tested scientific theory
-
There is little evidence regarding the absolute earliest instant of the expansion
-
Thus, the Big Bang theory cannot and does not provide any explanation for such an initial condition
-
-
03 Sep 12
-
16 Apr 12
-
08 Mar 12
-
The Big Bang theory is the prevailing cosmological model that explains the early development of the Universe.[1] According to the Big Bang theory, the Universe was once in an extremely hot and dense state which expanded rapidly. This rapid expansion caused the young Universe to cool and resulted in its present continuously expanding state. According to the most recent measurements and observations, this original state existed approximately 13.7 billion years ago,[
-
-
l5042026biiiiiiiiiiig bang
-
20 Dec 11
Devynn Pedellgood stuff
good explanation int he first section-
The Big Bang theory is the prevailing cosmological model that explains the early development of the Universe
-
According to the Big Bang theory, the Universe was once in an extremely hot and dense state which expanded rapidly. This rapid expansion caused the young Universe to cool and resulted in its present continuously expanding state
-
-
04 Nov 11
-
06 Jul 11
-
These ideas were initially taken as postulates, but today there are efforts to test each of them. For example, the first assumption has been tested by observations showing that largest possible deviation of the fine structure constant over much of the age of the universe is of order 10−5.[43] Also, general relativity has passed stringent tests on the scale of the solar system and binary stars while extrapolation to cosmological scales has been validated by the empirical successes of various aspects of the Big Bang theory.
-
If the large-scale Universe appears isotropic as viewed from Earth, the cosmological principle can be derived from the simpler Copernican principle, which states that there is no preferred (or special) observer or vantage point. To this end, the cosmological principle has been confirmed to a level of 10−5 via observations of the CMB.[notes 5] The Universe has been measured to be homogeneous on the largest scales at the 10% level.
-
-
21 Apr 11
Joan ChoiThe Big Bang theory developed from observations of the structure of the Universe and from theoretical considerations. In 1912 Vesto Slipher measured the first Doppler shift of a "spiral nebula" (spiral nebula is the obsolete term for spiral galaxies), and soon discovered that almost all such nebulae were receding from Earth. He did not grasp the cosmological implications of this fact, and indeed at the time it was highly controversial whether or not these nebulae were "island universes" outside our Milky Way.[14][15] Ten years later, Alexander Friedmann, a Russian cosmologist and mathematician, derived the Friedmann equations from Albert Einstein's equations of general relativity, showing that the Universe might be expanding in contrast to the static Universe model advocated by Einstein at that time.[16] In 1924, Edwin Hubble's measurement of the great distance to the nearest spiral nebulae showed that these systems were indeed other galaxies. Independently deriving Friedmann's equations in 1927, Georges Lemaître, a Belgian physicist and Roman Catholic priest, proposed that the inferred recession of the nebulae was due to the expansion of the Universe.[17]
-
kate moonThe Big Bang model or theory is the prevailing[citation needed] cosmological theory of the early development of the universe. According to the Big Bang model, the universe was originally in an extremely hot and dense state that expanded rapidly. This expansion caused the universe to cool and resulted in the present diluted state that continues to expand today. Based on the best available measurements as of 2010[update], the original state of the universe existed around 13.7 billion years ago,[1][2] which is often referred to as the time when the Big Bang occurred.[3][4] The theory is the most comprehensive and accurate explanation supported by scientific evidence and observations.[5][6]
-
23 Nov 10
-
06 Sep 10
-
According to the Big Bang model, the universe, originally in an extremely hot and dense state that expanded rapidly, has since cooled by expanding to the present diluted state, and continues to expand today.
-
-
11 Jun 10
-
he Big Bang is the prevailing cosmological theory of the early development of the universe. Cosmologists use the term Big Bang to refer to the idea that the universe was originally extremely hot and dense at some finite time in the past and has since cooled by expanding to a currently diluted state that continues to expand today. The theory is supported by the most comprehensive and accurate explanations from current scientific evidence and observation.[1][2] According to the best available measurements as of 2010[update], the initial conditions
-
The Big Bang is the prevailing cosmological theory of the early development of the universe. Cosmologists use the term Big Bang to refer to the idea that the universe was originally extremely hot and dense at some finite time in the past and has since cooled by expanding to a currently diluted state that continues to expand today. The theory is supported by the most comprehensive and accurate explanations from current scientific evidence and observation.[1][2] According to the best available measurements as of 2010[update], the initial conditions occurred around 13.3 to 13.9 billion years ago.[3][4]
-
-
-
22 Oct 09
-
27 Jun 09
-
13 Jun 09
Vasenta NarkiaThe Big Bang is a cosmological model of the initial conditions and subsequent development of the universe. It is supported by the most comprehensive and accurate explanations from current scientific evidence and observation.[1][2] As used by cosmologists, the term Big Bang generally refers to the idea that the universe has expanded from a primordial hot and dense initial condition at some finite time in the past, and continues to expand to this day.
Big Bang Big_Bang info reference wikipedia cosmology physics astronomy science universe
-
09 Jun 09
Matti NarkiaThe Big Bang is a cosmological model of the initial conditions and subsequent development of the universe. It is supported by the most comprehensive and accurate explanations from current scientific evidence and observation.[1][2] As used by cosmologists, the term Big Bang generally refers to the idea that the universe has expanded from a primordial hot and dense initial condition at some finite time in the past, and continues to expand to this day.
Big Bang Big Bang Big_Bang info reference wikipedia cosmology physics astronomy science universe
-
14 Nov 08
-
Without any evidence associated with the earliest instant of the expansion, the Big Bang theory cannot and does not provide any explanation for such an initial condition; rather, it describes and explains the general evolution of the universe since that instant
-
-
25 Jan 08
-
19 Jan 08
-
02 Jan 08
-
23 Aug 07
Would you like to comment?
Join Diigo for a free account, or sign in if you are already a member.