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Aug 13 2014 07:31am
Quote (Saenchai @ Aug 13 2014 02:29pm)
http://4.ii.gl/W_giI7Ah.png


nagyon jó, kezdem érteni, hogy ezekre a postokra szükség van
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Aug 13 2014 07:32am
Quote (Saenchai @ Aug 13 2014 01:29pm)
http://4.ii.gl/W_giI7Ah.png


nem, mert a TONIK a bitterest :DXD
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Aug 13 2014 07:33am
Cyclic model
A cyclic model (or oscillating model) is any of several cosmological models in which the universe follows infinite, self-sustaining cycles. For example, the oscillating universe theory briefly considered by Albert Einstein in 1930 theorized a universe following an eternal series of oscillations, each beginning with a big bang and ending with a big crunch; in the interim, the universe would expand for a period of time before the gravitational attraction of matter causes it to collapse back in and undergo a bounce.


Overview
In the 1920s, theoretical physicists, most notably Albert Einstein, considered the possibility of a cyclic model for the universe as an (everlasting) alternative to the model of an expanding universe. However, work by Richard C. Tolman in 1934 showed that these early attempts failed because of the cyclic problem: according to the Second Law of Thermodynamics, entropy can only increase.[1] This implies that successive cycles grow longer and larger. Extrapolating back in time, cycles before the present one become shorter and smaller culminating again in a Big Bang and thus not replacing it. This puzzling situation remained for many decades until the early 21st century when the recently discovered dark energy component provided new hope for a consistent cyclic cosmology.[2] In 2011, a five-year survey of 200,000 galaxies and spanning 7 billion years of cosmic time confirmed that "dark energy is driving our universe apart at accelerating speeds."[3][4]

One new cyclic model is a brane cosmology model of the creation of the universe, derived from the earlier ekpyrotic model. It was proposed in 2001 by Paul Steinhardt of Princeton University and Neil Turok of Cambridge University. The theory describes a universe exploding into existence not just once, but repeatedly over time.[5][6] The theory could potentially explain why a mysterious, repulsive form of energy known as the cosmological constant, which is accelerating the expansion of the universe, is several orders of magnitude smaller than predicted by the standard Big Bang model.

A different cyclic model relying on the notion of phantom energy was proposed in 2007 by Lauris Baum and Paul Frampton of the University of North Carolina at Chapel Hill.[7]

Other cyclic models include Conformal cyclic cosmology and Loop quantum cosmology.


The Steinhardt–Turok model
In this cyclic model, two parallel orbifold planes or M-branes collide periodically in a higher-dimensional space.[8] The visible four-dimensional universe lies on one of these branes. The collisions correspond to a reversal from contraction to expansion, or a big crunch followed immediately by a big bang. The matter and radiation we see today were generated during the most recent collision in a pattern dictated by quantum fluctuations created before the branes. After billions of years the universe reached the state we observe today; after additional billions of years it will ultimately begin to contract again. Dark energy corresponds to a force between the branes, and serves the crucial role of solving the monopole, horizon, and flatness problems. Moreover the cycles can continue indefinitely into the past and the future, and the solution is an attractor, so it can provide a complete history of the universe.

As Richard C. Tolman showed, the earlier cyclic model failed because the universe would undergo inevitable thermodynamic heat death.[1] However, the newer cyclic model evades this by having a net expansion each cycle, preventing entropy from building up. However, there remain major open issues in the model. Foremost among them is that colliding branes are not understood by string theorists, and nobody knows if the scale invariant spectrum will be destroyed by the big crunch. Moreover, as with cosmic inflation, while the general character of the forces (in the ekpyrotic scenario, a force between branes) required to create the vacuum fluctuations is known, there is no candidate from particle physics. [9]

The Baum–Frampton model
This more recent cyclic model of 2007 makes a different technical assumption concerning the equation of state of the dark energy which relates pressure and density through a parameter w.[7][10] It assumes w < −1 (a condition called phantom energy) throughout a cycle, including at present. (By contrast, Steinhardt–Turok assume w is never less than −1.) In the Baum–Frampton model, a septillionth (or less) of a second before the would-be Big Rip, a turnaround occurs and only one causal patch is retained as our universe. The generic patch contains no quark, lepton or force carrier; only dark energy – and its entropy thereby vanishes. The adiabatic process of contraction of this much smaller universe takes place with constant vanishing entropy and with no matter including no black holes which disintegrated before turnaround.

The idea that the universe "comes back empty" is a central new idea of this cyclic model, and avoids many difficulties confronting matter in a contracting phase such as excessive structure formation, proliferation and expansion of black holes, as well as going through phase transitions such as those of QCD and electroweak symmetry restoration. Any of these would tend strongly to produce an unwanted premature bounce, simply to avoid violation of the second law of thermodynamics. The surprising w < −1 condition may be logically inevitable in a truly infinitely cyclic cosmology because of the entropy problem. Nevertheless, many technical back up calculations are necessary to confirm consistency of the approach. Although the model borrows ideas from string theory, it is not necessarily committed to strings, or to higher dimensions, yet such speculative devices may provide the most expeditious methods to investigate the internal consistency. The value of w in the Baum–Frampton model can be made arbitrarily close to, but must be less than, −1.

Other cyclic models
Conformal cyclic cosmology - a general relativity based theory due to Roger Penrose in which the universe expands until all the matter decays and is turned to light - so there is nothing in the universe that has any time or distance scale associated with it. This permits it to become identical with the Big Bang, so starting the next cycle.
Loop quantum cosmology which predicts a "quantum bridge" between contracting and expanding cosmological branches.




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Aug 13 2014 07:33am
Quote (Saenchai @ Aug 13 2014 02:33pm)
Cyclic model
A cyclic model (or oscillating model) is any of several cosmological models in which the universe follows infinite, self-sustaining cycles. For example, the oscillating universe theory briefly considered by Albert Einstein in 1930 theorized a universe following an eternal series of oscillations, each beginning with a big bang and ending with a big crunch; in the interim, the universe would expand for a period of time before the gravitational attraction of matter causes it to collapse back in and undergo a bounce.


Overview
In the 1920s, theoretical physicists, most notably Albert Einstein, considered the possibility of a cyclic model for the universe as an (everlasting) alternative to the model of an expanding universe. However, work by Richard C. Tolman in 1934 showed that these early attempts failed because of the cyclic problem: according to the Second Law of Thermodynamics, entropy can only increase.[1] This implies that successive cycles grow longer and larger. Extrapolating back in time, cycles before the present one become shorter and smaller culminating again in a Big Bang and thus not replacing it. This puzzling situation remained for many decades until the early 21st century when the recently discovered dark energy component provided new hope for a consistent cyclic cosmology.[2] In 2011, a five-year survey of 200,000 galaxies and spanning 7 billion years of cosmic time confirmed that "dark energy is driving our universe apart at accelerating speeds."[3][4]

One new cyclic model is a brane cosmology model of the creation of the universe, derived from the earlier ekpyrotic model. It was proposed in 2001 by Paul Steinhardt of Princeton University and Neil Turok of Cambridge University. The theory describes a universe exploding into existence not just once, but repeatedly over time.[5][6] The theory could potentially explain why a mysterious, repulsive form of energy known as the cosmological constant, which is accelerating the expansion of the universe, is several orders of magnitude smaller than predicted by the standard Big Bang model.

A different cyclic model relying on the notion of phantom energy was proposed in 2007 by Lauris Baum and Paul Frampton of the University of North Carolina at Chapel Hill.[7]

Other cyclic models include Conformal cyclic cosmology and Loop quantum cosmology.


The Steinhardt–Turok model
In this cyclic model, two parallel orbifold planes or M-branes collide periodically in a higher-dimensional space.[8] The visible four-dimensional universe lies on one of these branes. The collisions correspond to a reversal from contraction to expansion, or a big crunch followed immediately by a big bang. The matter and radiation we see today were generated during the most recent collision in a pattern dictated by quantum fluctuations created before the branes. After billions of years the universe reached the state we observe today; after additional billions of years it will ultimately begin to contract again. Dark energy corresponds to a force between the branes, and serves the crucial role of solving the monopole, horizon, and flatness problems. Moreover the cycles can continue indefinitely into the past and the future, and the solution is an attractor, so it can provide a complete history of the universe.

As Richard C. Tolman showed, the earlier cyclic model failed because the universe would undergo inevitable thermodynamic heat death.[1] However, the newer cyclic model evades this by having a net expansion each cycle, preventing entropy from building up. However, there remain major open issues in the model. Foremost among them is that colliding branes are not understood by string theorists, and nobody knows if the scale invariant spectrum will be destroyed by the big crunch. Moreover, as with cosmic inflation, while the general character of the forces (in the ekpyrotic scenario, a force between branes) required to create the vacuum fluctuations is known, there is no candidate from particle physics. [9]

The Baum–Frampton model
This more recent cyclic model of 2007 makes a different technical assumption concerning the equation of state of the dark energy which relates pressure and density through a parameter w.[7][10] It assumes w < −1 (a condition called phantom energy) throughout a cycle, including at present. (By contrast, Steinhardt–Turok assume w is never less than −1.) In the Baum–Frampton model, a septillionth (or less) of a second before the would-be Big Rip, a turnaround occurs and only one causal patch is retained as our universe. The generic patch contains no quark, lepton or force carrier; only dark energy – and its entropy thereby vanishes. The adiabatic process of contraction of this much smaller universe takes place with constant vanishing entropy and with no matter including no black holes which disintegrated before turnaround.

The idea that the universe "comes back empty" is a central new idea of this cyclic model, and avoids many difficulties confronting matter in a contracting phase such as excessive structure formation, proliferation and expansion of black holes, as well as going through phase transitions such as those of QCD and electroweak symmetry restoration. Any of these would tend strongly to produce an unwanted premature bounce, simply to avoid violation of the second law of thermodynamics. The surprising w < −1 condition may be logically inevitable in a truly infinitely cyclic cosmology because of the entropy problem. Nevertheless, many technical back up calculations are necessary to confirm consistency of the approach. Although the model borrows ideas from string theory, it is not necessarily committed to strings, or to higher dimensions, yet such speculative devices may provide the most expeditious methods to investigate the internal consistency. The value of w in the Baum–Frampton model can be made arbitrarily close to, but must be less than, −1.

Other cyclic models
Conformal cyclic cosmology - a general relativity based theory due to Roger Penrose in which the universe expands until all the matter decays and is turned to light - so there is nothing in the universe that has any time or distance scale associated with it. This permits it to become identical with the Big Bang, so starting the next cycle.
Loop quantum cosmology which predicts a "quantum bridge" between contracting and expanding cosmological branches.




http://mythologian.net/wp-content/uploads/2013/10/Ouroboros.png


jarabek szerint ez a humor
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Aug 13 2014 07:34am
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Aug 13 2014 07:34am
Quote (Saenchai @ Aug 13 2014 02:34pm)
http://www.youtube.com/watch?v=SIFALPsI6AM


röhögök :D
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Aug 13 2014 07:35am
Quote (TuskesVanek @ Aug 13 2014 01:33pm)
jarabek szerint ez a humor


jerebakg szerint a világ

:XD

az a tard műsor vmi mesefilm ilyen fogyaték baba mászkál benne
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Aug 13 2014 07:37am
A kozmikus felfúvódás, vagyis az ősrobbanás utáni gyors tágulás első közvetlen bizonyítéka egyes kutatók szerint azt is alátámasztja, hogy univerzumunk csupán egy a sok közül.

Amennyiben megerősítést nyernek a gravitációs hullámokkal kapcsolatos felfedezések, olyan bizonyíték lesz a tudósok kezében, ami megkérdőjelezhetetlenné teszi, hogy 13,8 milliárd évvel ezelőtt, közvetlenül az ősrobbanás után a tér-idő a fénysebesség sokszorosával tágult.

Az új kutatás hitelt ad a multiverzum elméletnek is, mely szerint, amikor az univerzum exponenciális növekedésbe kezdett az ősrobbanás utáni másodperc első parányi töredékében. A tér-idő egyes részei gyorsabban tágultak, mint mások, ez tér-idő "buborékokat" eredményezhetett, melyek más univerzumokká fejlődhettek. Az ismert univerzum saját fizikai törvényekkel rendelkezik, míg más univerzumok esetében is kialakulhattak saját, a miénktől eltérő törvények.

"Nehéz olyan felfúvódási modelleket építeni, melyek ne vezetnének el egy multiverzumhoz" - mondta Alan Guth, az MIT elméleti fizikusa. "Nem lehetetlen, ezért úgy vélem, újabb kutatások kell végezni. A felfúvódás bizonyítéka abba az irányba visz minket, ahol a multiverzum ötletét komolyan kell venni"

Más kutatók is egyetértenek a felfúvódás és a multiverzum kapcsolatában. "A legtöbb felfúvódási modellben, ha jelen van a felfúvódás, akkor a multiverzum is megjelenik" - mondta a Stanford Egyetem elméleti fizikusa, Andrei Linde, aki nem vett részt az új tanulmányban. "Lehetséges olyan modellek kifejlesztése is, amik nem teszik lehetővé a multiverzumot, de ez elég bonyolult. Minden kísérlet, ami egyre nagyobb hitelt ad a felfúvódási elméletnek, egyre közelebb visz a multiverzum valós lehetőségéhez"

Amikor Guth és munkatársai több mint 30 éve előálltak a kozmikus felfúvódással, a tudósok letesztelhetetlennek gondolták az elméletet, ma azonban már képesek tanulmányozni az ősrobbanás visszamaradt fényéből, az úgynevezett kozmikus mikrohullámú háttérsugárzásból. Az új tanulmányban, ami a Harvard-Smithsonian Asztrofizikai Központ John Kovac által vezetett csapatának nevéhez fűződik, egy jól kivehető hullámot fedeztek fel a háttérsugárzás polarizációs sémájában, ami a tér-idő gyors tágulása következtében kialakult gravitációs hullámok jele.

Linde szerint az ismert univerzum, csupán egy a buborékok közül, ami mellett sok másiknak is léteznie kell a kozmikus anyagban. "Gondoljunk egyfajta instabil állapotra" - magyarázta Linde. "Egy dombon állunk, ahonnan erre, vagy arra is legurulhatunk, ha ittas állapotba kerülünk. A felfúvódás a tér instabilitása, ami hatással van a tágulására. Van valamink, ami exponenciálisan növekszik. Ha elengedjük, folytatja exponenciális terjeszkedését. Az ismert univerzum egy lehetősége annak, hogy valami félresiklott ebben az instabilitásban, ami nagyon jó nekünk, mivel megalkotta a mi életterünket. Most, hogy tudjuk, hogy bármi félresikerülhet, gyakorlatilag végtelen az ilyen lehetőségek száma, amíg a folyamat zajlik"



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Aug 13 2014 07:38am
np
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