26-06-11

Multiverse From Wikipedia, the free encyclopedia

cosmology,multiverse,

copyright :

http://commons.wikimedia.org/wiki/File:Multiverse.jpg

 

The multiverse (or meta-universe, metaverse) is the hypothetical set of multiple possible universes (including the historical universe we consistently experience) that together comprise everything that exists: the entirety of space, time, matter, and energy as well as the physical laws and constants that describe them.


The term was coined in 1895 by the American philosopher and psychologist William James.


The various universes within the multiverse are sometimes called parallel universes.


The structure of the multiverse, the nature of each universe within it and the relationship between the various constituent universes, depend on the specific multiverse hypothesis considered.


Multiverses have been hypothesized in cosmology, physics, astronomy, religion, philosophy, transpersonal psychology and fiction, particularly in science fiction and fantasy.


In these contexts, parallel universes are also called "alternative universes", "quantum universes", "interpenetrating dimensions", "parallel dimensions", "parallel worlds", "alternative realities", "alternative timelines", and "dimensional planes," among others.

 

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http://en.wikipedia.org/wiki/Multiverse

 

22-11-10

Penrose: WMAP Shows Evidence of ‘Activity’ Before Big Bang

22nd November 2010


Have scientists seen evidence of time before the Big Bang, and perhaps a verification of the idea of the cyclical universe?


One of the great physicists of our time, Roger Penrose from the University of Oxford, has published a new paper saying that the circular patterns seen in the WMAP mission data on the Cosmic Microwave Background suggest that space and time perhaps did not originate at the Big Bang but that our universe continually cycles through a series of “aeons,” and we have an eternal, cyclical cosmos.


His paper also refutes the idea of inflation, a widely accepted theory of a period of very rapid expansion immediately following the Big Bang.

 

Sir Roger Penrose.jpg

 

Copyright - Credits : Universe Today

 

http://www.universetoday.com/79750/penrose-wmap-shows-evi... 

 

11-11-10

Cosmology - animation photo from Big Bang To Present Time

FromBigBangtopresenttime.jpg

18-09-10

Astronomen nemen afscheid van oerknalsatelliet WMAP !

 

13 september 2010

 

copyright

 

allesoversterrenkunde.nl

 

http://allesoversterrenkunde.nl/nieuws/4117-Astronomen-ne...

 

WMAP.jpg

 

Zonder veel ophef hebben astronomen op 8 september afscheid genomen van de Wilkinson Microwave Anisotropy Probe, beter bekend als WMAP.

 

De satelliet, die negen jaar lang de zogeheten kosmische achtergrondstraling heeft onderzocht, is met zijn eigen raketmotor in een veilige baan om de zon gemanoeuvreerd.

 

De WMAP-satelliet werd op 30 juni 2001 gelanceerd naar 'vaste' locatie die vanaf de zon gezien anderhalf miljoen kilometer achter de aarde ligt.

 

Enkele maanden later begon hij met het in kaart brengen van de kosmische achtergrondstraling - de straling die een overblijfsel is van de oerknal, die bijna veertien miljard jaar geleden het ontstaan van het heelal inluidde.

 

Al in 2003 werd WMAP door het wetenschappelijke tijdschrift Science uitgeroepen tot 'doorbraak van het jaar'.

 

De resultaten van de WMAP-metingen zijn in overeenstemming met het standaardmodel dat vrijwel alle astronomen voor het ontstaan van het heelal hanteren.

 

Vastgesteld is dat de oerknal waaruit ons heelal is voortgekomen 13,73 miljard jaar geleden moet hebben plaatsgevonden.

 

Ook is uit het onderzoek gebleken dat het heelal voor slechts 4,6 procent uit normale materie bestaat.

 

 

 

UniversePie.jpg

De overige 95,4 procent wordt gevormd door donkere materie, die geen enkele vorm van waarneembare straling uitzendt maar wel zwaartekracht uitoefent, en een mysterieuze donkere energie, die het heelal versneld laat uitdijen.

 

Toegevoegd door Eddy Echternach

 

www.astronieuws.nl

 

Links

 

http://nl.wikipedia.org/wiki/Wilkinson_Microwave_Anisotro...

 

http://map.gsfc.nasa.gov/

16-04-10

ANTIMATTER - WHERE DID IT ALL GO ?

For many years, the absence of antimatter in the Universe has tantalised particle physicists and cosmologists: while the Big Bang should have created equal amounts of matter and antimatter, we do not observe any primordial antimatter today. Where has it gone? The LHC experiments have the potential to unveil natural processes that could hold the key to solving this paradox. Every time that matter is created from pure energy, equal amounts of particles and antiparticles are generated. Conversely, when matter and antimatter meet, they annihilate and produce light. Antimatter is produced routinely when cosmic rays hit the Earth's atmosphere, and the annihilations of matter and antimatter are observed during physics experiments in particle accelerators. If the Universe contained antimatter regions, we would be able to observe intense fluxes of photons at the boundaries of the matter/antimatter regions. “Experiments measuring the diffuse gamma-ray background in the Universe would be able to observe these light emissions”, confirms Antonio Riotto of CERN's Theory group. “In the absence of such evidence, we can conclude that matter domains are at least the size of the entire visible Universe”, he adds. What caused the disappearance of antimatter in favour of matter? “In 1967, the Russian physicist Andrej Sakharov pointed out that forces discriminating between matter and antimatter, called “CP-violating” effects, could have modified the initial matter-antimatter symmetry when deviations from the thermal equilibrium of the Universe occured”, says Antonio Riotto. In the cold Universe today, we can only observe very rare CP-violating effects in which Nature prefers the creation of matter over antimatter. Following their discovery in the decays of K-mesons containing strange quarks, they have now also been observed in the decays of B mesons, which contain bottom quarks. Today, scientists think that the early Universe might have gone through a transition phase in which the thermodynamic equilibrium was broken, when the density of the Universe was very high and the average temperature was one billion or more times that inside the Sun. "Some physicists think that this might have happened through the formation of ‘bubbles’ which have progressively expanded, thus ‘imposing’ their new equilibrium on the whole pre-existent Universe", explains Antonio Riotto. Whatever the real dynamics of this phase actually were, the important thing is that one particle of matter in every 10 billion survived, while all the others annihilated with the corresponding antiparticles. How can the LHC help to solve the mystery? By studying rare decays, experiments can bring us more accurate information about phenomena related to CP-violation involving both known and new particles, such as mesons containing both bottom and strange quarks. Moreover, if new supersymmetric particles are discovered at the LHC, some of the possible scenarios leading to a non-equilibrium phase could find experimental support. "If the LHC finds a Higgs boson with a mass less than about 130 GeV, and if this discovery comes with the detection of a light supersymmetric particle called ‘stop‘, this could be the experimental proof that the non-equilibrium phase happened through the formation of bubbles", concludes Antonio Riotto. In any case, since the disappearance of primordial antimatter cannot be explained by the current Standard Model theory, it is clear that we have to look for something new. Scientists are exploring different avenues but, given the fact that what we observe represents only about 4% of the total energy and matter that the Universe is made of, one can guess that part of the key to solving the antimatter mystery could be held in the yet unknown part of the Universe. With its very high discovery potential, the LHC will certainly help shed light on the whole issue.antimatterCOPYRIGHT CERN BULLETIN URL :http://cdsweb.cern.ch/journal/CERNBulletin/2010/16/News%20Articles/1255394?ln=en

03-01-10

WAT WAS ER VOOR DE BIG BANG ?

Onze tijd is begonnen met de oerknal. De tijd erover extrapoleren, is niet evident.Zoals 'ten noorden van de noordpool' niet bestaat, is iets als 'voor de oerknal' ook niet zomaar zinvol.We kunnen erover speculeren, in de zin dat ruimte en tijd in mathematische concepten kunnen gegoten worden, en de wiskunde laat vele varianten toe. Maar in termen van fysisch experimenteren, en dus soliede kennis opbouwen, is de oerknal een grens waar we moeilijk overheen geraken: naarmate we dichter bij de oerknal komen, stijgen dichtheid, druk, temperatuur, maar ook onze onwetendheid. In de oerknal worden ze alle - ook onze onwetendheid dus - oneindig. En voorbij oneindig kan je niet extrapoleren... Besef aub dat wij product zijn van het heelal. Wij, dat zijn de atomen waaruit wij bestaan, maar ook de concepten die we hanteren, inclusief ruimte en tijd. Spreken over die concepten als voorafgaande voorwaarde voor het heelal, is een stap te ver.Deze vraag werd beantwoord door:Prof. Christoffel Waelkens Gewoon Hoogleraar SterrenkundebigbangCopyright : http://ikhebeenvraag.be/vraag/6749

22-12-08

What came before the Big Bang ?

A question that has been pondered by scientists and philosophers alike could soon be answered, thanks to a mathematical model that explains an anomaly in the early Universe."It's no longer completely crazy to ask what happened before the Big Bang," says Marc Kamionkowski, Caltech's Robinson Professor of Theoretical Physics and Astrophysics. Kamionkowski and colleagues propose a mathematical model to explain an anomaly in what is widely believed to be a Universe of uniformly distributed radiation and matter. WMAP’s all-sky picture of the infant Universe reveals 13.7 billion year old temperature fluctuations (shown as colour differences) that correspond to the seeds that grew to become the galaxies. These variations are 'lop-sided' suggesting asymmetric density variations. Image: NASA / WMAP Science Team.The notion of space expanding exponentially from a blank canvas in the instant following the so-called Big Bang is known as inflation, and the simplest interpretation of the theory requires the Universe to be uniform in all directions. The energy that permeated the Universe 400,000 years after the Big Bang – essentially an ‘echo’ from the Big Bang – is known as the Cosmic Microwave Background, or CMB, and was mapped in detail by NASA’s Wilkinson Microwave Anisotropy Probe (WMAP), revealing that tiny fluctuations in the CMB seemed to be the same everywhere, fitting with the theory of inflation. "If your eyes measured radio frequency, you'd see the entire sky glowing. This is what WMAP sees," describes Kamionkowksi. WMAP depicts the CMB as an afterglow of light that has decayed to microwave radiation as the Universe expanded over the past 13.7 billion years.The problem with inflation, however, is that it predicts the Universe began uniformly, and earlier this year a detailed study suggested that there is in fact a pronounced asymmetry in the CMB, with intensely varied deviations from the average value in one half of the sky than the other. "It's a certified anomaly," remarks Kamionkowski. "But since inflation seems to do so well with everything else, it seems premature to discard the theory." A representation of the evolution of the Universe over 13.7 billion years. The far left depicts the earliest moment we can now probe, when a period of inflation produced a burst of exponential growth in the Universe. Image: NASA/WMAP Science Team.The team are now trying to address the remarkable asymmetry within the bounds of inflation. They began by testing whether the value of a single energy field thought to have driven inflation, called the inflaton, was different on one side of the Universe than the other. But by changing the mean value of the inflation, the mean temperature and amplitude of energy variations in space also changed, violating constraints to the homogeneity of the Universe. So they explored a second energy field, called the curvaton, which has already been proposed to give rise to the density fluctuations observed in the CMB. The team introduced a perturbation to the curvaton field that turns out to affect only how temperature varies from point to point through space, while preserving its average value. This new model suggests more cold than hot spots in the CMB, a predication that will be tested by ESA’s Planck satellite that is scheduled to launch in April 2009."Inflation is a description of how the Universe expanded," says Adrienne Erickcek, a graduate student working on the project. "Its predictions have been verified, but what drove it and how long did it last? This is a way to look at what happened during inflation, which has a lot of blanks waiting to be filled in."Furthermore, the theoretical perturbation that the researchers introduced to the model may also offer the first glimpse at what came before the Big Bang, because it could represent an imprint inherited from the time before inflation. That is, it could be a signature of a structure left over from something that produced our Universe. Perhaps an older universe from which our own Universe was born could explain this anomaly, or could it be due to concurrently existing universes – a Multiverse – in which there are big bangs occurring at different points in the Universe at different times, generating a number of separate universes within our Multiverse?"All of that stuff is hidden by a veil, observationally," says Kamionkowski. "If our model holds up, we may have a chance to see beyond this veil."With the launch of Planck not far off we may not have too long to wait for the answers to the questions posed by Kamionkowski and others, and of the nature of how our Universe came to be. The study appears in the 16 December edition of the journal Physical Review D.COPYRIGHT URL http://astronomynow.com/081208WhatcamebeforetheBigBang.htmlbigbang2

15-08-08

The LHC is asking some Big Questions about the universe we live in

How did our universe come to be the way it is? The Universe started with a Big Bang – but we don’t fully understand how or why it developed the way it did. The LHC will let us see how matter behaved a tiny fraction of a second after the Big Bang. Researchers have some ideas of what to expect – but also expect the unexpected!What kind of Universe do we live in? Many physicists think the Universe has more dimensions than the four (space and time) we are aware of. Will the LHC bring us evidence of new dimensions? Gravity does not fit comfortably into the current descriptions of forces used by physicists. It is also very much weaker than the other forces. One explanation for this may be that our Universe is part of a larger multi dimensional reality and that gravity can leak into other dimensions, making it appear weaker. The LHC may allow us to see evidence of these extra dimensions - for example, the production of mini-black holes which blink into and out of existence in a tiny fraction of a second.What happened in the Big Bang? What was the Universe made of before the matter we see around us formed? The LHC will recreate, on a microscale, conditions that existed during the first billionth of a second of the Big Bang.At the earliest moments of the Big Bang, the Universe consisted of a searingly hot soup of fundamental particles - quarks, leptons and the force carriers. As the Universe cooled to 1000 billion degrees, the quarks and gluons (carriers of the strong force) combined into composite particles like protons and neutrons. The LHC will collide lead nuclei so that they release their constituent quarks in a fleeting ‘Little Bang’. This will take us back to the time before these particles formed, re-creating the conditions early in the evolution of the universe, when quarks and gluons were free to mix without combining. The debris detected will provide important information about this very early state of matter.Where is the antimatter? The Big Bang created equal amounts of matter and antimatter, but we only see matter now. What happened to the antimatter?Every fundamental matter particle has an antimatter partner with equal but opposite properties such as electric charge (for example, the negative electron has a positive antimatter partner called the positron). Equal amounts of matter and antimatter were created in the Big Bang, but antimatter then disappeared. So what happened to it? Experiments have already shown that some matter particles decay at different rates from their anti-particles, which could explain this. One of the LHC experiments will study these subtle differences between matter and antimatter particles.Why do particles have mass? Why do some particles have mass while others don’t? What makes this difference? If the LHC reveal particles predicted by theory it will help us understand this. Particles of light (known as photons) have no mass. Matter particles (such as electrons and quarks) do – and we’re not sure why. British physicist, Peter Higgs, proposed the existence of a field (the Higg’s Field), which pervades the entire Universe and interacts with some particles and this gives them mass. If the theory is right then the field should reveal itself as a particle (the Higg’s particle). The Higg’s particle is too heavy to be made in existing accelerators, but the high energies of the LHC should enable us to produce and detect it.What is our Universe made of? Ninety-six percent of our Universe is missing! Much of the missing matter is stuff researchers have called ‘dark matter’. Can the LHC find out what it is made of?The theory of ‘supersymmetry’ suggests that all known particles have, as yet undetected, ‘superpartners’. If they exist, the LHC should find them. These ‘supersymmetric’ particles may help explain one mystery of the Universe – missing matter. Astronomers detect the gravitational effects of large amounts of matter that can’t be seen and so is called ‘Dark Matter’. One possible explanation of dark matter is that it consists of supersymmetric particles.Copyright http://www.lhc.ac.uk/the-big-questions.htmlLHC_hall

24-04-08

Klassieke benadering van dichtheidsfluctuaties in heelal klopt

blogphotoKlassieke benadering van dichtheidsfluctuaties in heelal kloptWoensdag 7 mei 2008, 12:00 uurPromotieDhr. M.P. van der Meulen/ Natuurkunde Cold Electroweak Baryogenesis and Quantum Cosmological CorrelationsMeindert van der Meulen bespreekt in zijn proefschrift twee onderwerpen uit de theoretische kosmologie. Het eerste heeft te maken met de asymmetrie tussen materie en anti-materie in het heelal. Algemeen wordt aangenomen dat deze asymmetrie in het vroege heelal gevormd is, tijdens een proces dat baryogenese wordt genoemd. Het is echter onduidelijk hoe dit proces werkt. Van der Meulen onderzocht twee aspecten van een mogelijk scenario, dat ‘koude elektrozwakke baryogenese' heet: het mechanisme van deeltjesproductie en de grootte van de asymmetrie. Hij beargumenteert dat dit scenario uitgebreid zou moeten worden om de waargenomen asymmetrie te kunnen verklaren. Daarnaast onderzocht Van der Meulen de dichtheidsfluctuaties in het heelal. In het huidige heelal zijn er grote fluctuaties in materiedichtheid: in sterren, sterrenstelsels en clusters van sterrenstelsels is de dichtheid groot, maar daarbuiten heel klein. Deze grote fluctuaties zijn ontstaan onder de invloed van zwaartekracht uit heel kleine dichtheidsfluctuaties. Algemeen wordt aangenomen dat die eerste, kleine dichtheidsfluctuaties veroorzaakt zijn door kwantumfluctuaties tijdens inflatie. Dit is een periode die waarschijnlijk heeft plaatsgevonden vlak na de oerknal, waarin de ruimte exponentieel snel is uitgedijd. Van der Meulen bestudeerde kwantumcorrecties voor de berekeningen van deze eerste dichtheidsfluctuaties. Een vaak gebruikte benadering, de klassieke benadering, bleek goed te zijn; afwijkingen verschijnen pas op hogere orde.Promotordhr. prof. dr. J. SmitLocatieAgnietenkapelOudezijds Voorburgwal 2311012 EZ AmsterdamDeelnameToegang vrijBron: UvA Persvoorlichtingpersvoorlichting@uva.nlcopyright http://www.uva.nl/onderzoek/actuelepromoties.cfm/7F88752C-1321-B0BE-A46467E453DE0DE4

13-02-08

Jong, helder sterrenstelsel ontdekt van 12,8 miljoen jaar oud.

Nasa’s Hubble en Spitzer ruimtetelescopen hebben één van de jongste en helderste sterrenstelsels ontdekt die zo’n 700 miljoen jaar na de Big Bang ontstaan is.Astronoom Garth Illingworth van the University of California, Santa Cruz zegt dat de leden van het team verbaasd waren dat ze dergelijk helder sterrenstelsel van 12,8 miljard jaar oud gevonden hebben. Het stelsel kan meer informatie geven over het ontstaan en evolutie van dergelijke sterrenstelsels. De James Webb ruimtetelescoop die gelanceerd wordt in 2013 zal zeker het object aan verder onderzoek onderwerpen.youngestgalaxies

16-01-08

Het heelal 379.000 jaar na de Big Bang

De Wilkinson Microwave Anisotropy Probe of WMAP is een satelliet die tot taak heeft de temperatuurfluctuaties van de kosmische achtergrondstraling in kaart te brengen. WMAP is op 30 juni 2001 gelanceerd en bereikte op 1 oktober 2001 zijn observatiepositie op Lagrangepunt 2 (L2). Dat punt bevindt zich op 1,5 miljoen kilometer afstand aan de nachtzijde van de aarde. WMAP heeft een veel groter oplossend vermogen dan de eerdere COBE satelliet. Deze afbeelding toont het "oudste licht" van het heelal, 379.000 jaar na de oerknal. De kaart toont de zeer geringe temperatuurverschillen in het jonge heelal. Hoe roder, hoe warmer en hoe blauwer hoe koeler. De resolutie van de waarnemingen bedraagt 1 miljoenste graad.In februari 2003 waren de eerste resultaten beschikbaar in de vorm van uiterst gedetailleerde en nauwkeurige waarnemingen van de achtergrondstraling. De straling die werd waargenomen dateert van 379.000 jaar na de oerknal. De temperatuur van de sindsdien afgekoelde straling werd bepaald op 2,73 kelvin.Dankzij WMAP kwamen de wetenschappers er verder achter dat de eerste sterren eerder waren ontstaan dan gedacht: 200 miljoen jaar na de oerknal. Ook kon de ouderdom van het heelal nauwkeurig (met een marge van ± 1%.) worden vastgesteld op 13,7 miljard jaar. Een ander wetenschappelijk resultaat is de bevestiging van de voorspelling van de inflatietheorie dat het heelal niet gekromd is, maar vlak.copyright wikipediawmap

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