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==fine Timeline (da CANCELLARE)==

TheLa cosmicradiazione microwavedi backgroundfondo wasvenne predictedpredetta innel 1948 byda [[George Gamow]], [[Ralph Alpher]], and [[Robert Herman]].<ref>

{{cite journal|last=Gamow|first=G.|year=1948|title=The Origin of Elements and the Separation of Galaxies|journal=[[Physical Review]]|volume=74|issue=4|pages=505–506|doi=10.1103/PhysRev.74.505.2}}</ref><ref>

{{cite journal|last=Gamow|first=G.|year=1948|title=The evolution of the universe|journal=[[Nature (journal)|Nature]]|volume=162|pages=680–682|doi=10.1038/162680a0}}</ref><ref>

{{cite journal|last=Alpher|first=R. A.|last2=Herman|first2=R. C.|year=1948|title=On the Relative Abundance of the Elements|journal=[[Physical Review]]|volume=74|issue=12|pages=1737–1742|doi=10.1103/PhysRev.74.1737}}</ref>.

{{cite journal|last=Alpher|first=R. A.|last2=Herman|first2=R. C.|year=1948|title=On the Relative Abundance of the Elements|journal=[[Physical Review]]|volume=74|issue=12|pages=1737–1742|doi=10.1103/PhysRev.74.1737}}</ref> Alpher and Herman were able to estimate the temperature of the cosmic microwave background to be 5 K, though two years later they re-estimated it at 28 K.<ref group="nb">This high estimate was due to an mis-estimate of the Hubble constant by Alfred Behr, which could not be replicated and was later abandoned for the earlier estimate.</ref> Although there were several previous estimates of the temperature of space,<ref group="nb">See the timeline.</ref> these suffered from two flaws. First, they were measurements of the [[effective temperature|''effective'' temperature]] of space and did not suggest that space was filled with a thermal [[Planck spectrum]]. Next, they depend on our being at a special spot at the edge of the [[Milky Way galaxy]] and they did not suggest the radiation is isotropic. The estimates would yield very different predictions if Earth happened to be located elsewhere in the Universe.<ref>

{{cite journal|last=Assis|first=A. K. T.|last2=Neves|first2=M. C. D.|year=1995|title=History of the 2.7 K Temperature Prior to Penzias and Wilson|url=http://www.ifi.unicamp.br/~assis/Apeiron-V2-p79-84(1995).pdf|journal=[[Apeiron (journal)|Apeiron]]|volume=2|issue=3|pages=79–87|doi=}} but see also {{cite web|last=Wright|first=E. L.|year=2006|title=Eddington's Temperature of Space|url=http://www.astro.ucla.edu/~wright/Eddington-T0.html|publisher=UCLA|accessdate=2008-12-11}}</ref>

Alpher e Herman sono stati in grado di stimare la temperatura della radiazione cosmica di fondo a 5 K, anche se due anni dopo la ricalcolano a 28 K<ref group="nb">Questa stima è così elevata a causa di una sottostima della [[costante di Hubble]] da parte di Alfred Behr, che non poteva essere replicata, e fu in seguito abbandonata per la stima precedente.</ref>. Anche se ci sono state diverse stime precedenti della temperatura dello spazio<ref group="nb">Si veda la tabella della timeline.</ref>, queste soffrivano di due difetti. In primo luogo, erano misure della [[temperatura effettiva]] dello spazio e non lasciava supporre che lo spazio è stato riempito con uno [[corpo nero|spettro termico di Planck]]. Poi, dipendono dalla nostra posizione speciale ai margini della [[Via Lattea]] e non specificano che la radiazione è isotropa. Le stime produrrebbe previsioni molto diverse se la Terra si trovasse in un altro punto dell'universo<ref>

The 1948 results of Alpher and Herman were discussed in many physics settings through about 1955, when each left the Applied Physics Laboratory at Johns Hopkins University. The mainstream astronomical community, however, was not intrigued at the time by cosmology. Alpher and Herman's prediction was rediscovered by [[Yakov Zel'dovich]] in the early 1960s, and independently predicted by [[Robert Dicke]] at the same time. The first published recognition of the CMB radiation as a detectable phenomenon appeared in a brief paper by [[Soviet Union|Soviet]] astrophysicists [[A. G. Doroshkevich]] and [[Igor Dmitriyevich Novikov|Igor Novikov]], in the spring of 1964.<ref>{{cite web|last=Penzias|first=A. A.|year=2006|title=The origin of elements|url=http://nobelprize.org/nobel_prizes/physics/laureates/1978/penzias-lecture.pdf|work=Nobel lecture|publisher=[[Nobel Foundation]]|accessdate=2006-10-04}}</ref> In 1964, [[David Todd Wilkinson]] and Peter Roll, Dicke's colleagues at [[Princeton University]], began constructing a Dicke radiometer to measure the cosmic microwave background.<ref>

{{cite journal|last=Assis|first=A. K. T.|last2=Neves|first2=M. C. D.|year=1995|title=History of the 2.7 K Temperature Prior to Penzias and Wilson|url=http://www.ifi.unicamp.br/~assis/Apeiron-V2-p79-84(1995).pdf|journal=[[Apeiron (journal)|Apeiron]]|volume=2|issue=3|pages=79–87|doi=}} bute seesi alsoveda anche {{cite web|last=Wright|first=E. L.|year=2006|title=Eddington's Temperature of Space|url=http://www.astro.ucla.edu/~wright/Eddington-T0.html|publisher=UCLA|accessdate=2008-12-11}}</ref>.

{{cite journal|last=Dicke|first=R. H.|year=1946|title=The Measurement of Thermal Radiation at Microwave Frequencies|journal=[[Review of Scientific Instruments]]|volume=17|pages=268–275|doi=10.1063/1.1770483}} This basic design for a radiometer has been used in most subsequent cosmic microwave background experiments.</ref> In 1965, [[Arno Penzias]] and [[Robert Woodrow Wilson]] at the [[Crawford Hill]] ___location of [[Bell Telephone Laboratories]] in nearby [[Holmdel Township, New Jersey]] had built a Dicke radiometer that they intended to use for radio astronomy and satellite communication experiments. Their instrument had an excess 3.5 K [[noise temperature|antenna temperature]] which they could not account for. After receiving a telephone call from Crawford Hill, Dicke famously quipped: "Boys, we've been scooped."<ref name="apj142:419" /><ref>

TheI 1948risultati resultsdel of1948 di Alpher ande Herman werevennero discusseddiscussi infino manyal physics1955, settingsquando throughognuno aboutdi 1955,loro whenlasciò eachil left''Laboratorio thedi AppliedFisica PhysicsApplicata'' Laboratory atdella [[Johns Hopkins University]]. TheLa mainstreamcomunità astronomical communityastronomica, howevertuttavia, wasnon notera intriguedincuriosita ata thesuo timetempo bydalla cosmologycosmologia. La predizione di Alpher ande Herman's prediction wasfu rediscoveredriscoperta byda [[Yakov Zel'dovich]] inall'inizio thedegli earlyanni 1960s1960, ande independentlyindipendentemente predictedpredetta byda [[Robert Dicke]] at the same timecontemporaneamente. TheLa firstprima publishedpubblicazione recognitiondella ofradiazione thedi CMBfondo radiationcome asun afenomeno detectablerilevabile phenomenon appearedapparse in aun briefbreve paperelaborato bydegli astrofisici [[SovietUnione UnionSovietica|Sovietsovietici]] astrophysicists [[A. G. Doroshkevich]] ande [[Igor Dmitriyevich Novikov|Igor Novikov]], innella theprimavera spring ofdel [[1964.]]<ref>{{cite web|last=Penzias|first=A. A.|year=2006|title=The origin of elements|url=http://nobelprize.org/nobel_prizes/physics/laureates/1978/penzias-lecture.pdf|work=Nobel lecture|publisher=[[Nobel Foundation]]|accessdate=2006-10-04}}</ref>. InNel 1964, [[David Todd Wilkinson]] ande [[Peter Roll]], Dicke'scolleghi colleaguesdi at[[Robert Dicke]] all'[[PrincetonUniversità Universitydi Princeton]], beganiniziarono constructingla acostruzione di un radiometro Dicke radiometerper tomisurare measurela theradiazione cosmiccosmica microwavedi background.fondo<ref>

{{cite journal|last=Dicke|first=R. H.|year=1946|title=The Measurement of Thermal Radiation at Microwave Frequencies|journal=[[Review of Scientific Instruments]]|volume=17|pages=268–275|doi=10.1063/1.1770483}} This basic design for a radiometer has been used in most subsequent cosmic microwave background experiments.</ref>. Nel 1965, Arno Penzias e Robert Woodrow Wilson nel luogo Crawford Hill di Bell Telephone Laboratories nella vicina Holmdel Township, New Jersey aveva costruito un radiometro Dicke che intendevano utilizzare per la radioastronomia e gli esperimenti di comunicazione via satellite. Il loro strumento ha avuto un eccesso di temperatura di 3,5 K antenna che non riuscivano a spiegare. Dopo aver ricevuto una telefonata da Crawford Hill, Dicke famosa frase: "Ragazzi, siamo stati scavati." [1] [34] [35] Una riunione tra i gruppi di Princeton e Crawford Hill stabilito che la temperatura di antenna era effettivamente dovuto il forno a microonde sfondo. Penzias e Wilson ha ricevuto il Premio Nobel 1978 per la Fisica per la scoperta [36].

{{cite journal|last=Dicke|first=R. H.|year=1946|title=The Measurement of Thermal Radiation at Microwave Frequencies|journal=[[Review of Scientific Instruments]]|volume=17|pages=268–275|doi=10.1063/1.1770483}} This basic design for a radiometer has been used in most subsequent cosmic microwave background experiments.</ref> In 1965, [[Arno Penzias]] and [[Robert Woodrow Wilson]] at the [[Crawford Hill]] ___location of [[Bell Telephone Laboratories]] in nearby [[Holmdel Township, New Jersey]] had built a Dicke radiometer that they intended to use for radio astronomy and satellite communication experiments. Their instrument had an excess 3.5 K [[noise temperature|antenna temperature]] which they could not account for. After receiving a telephone call from Crawford Hill, Dicke famously quipped: "Boys, we've been scooped."<ref name="apj142:419" /><ref>

{{cite journal|last=Dicke|first=R. H.|coauthors=''et al.''|year=1965|title=Cosmic Black-Body Radiation|journal=[[Astrophysical Journal]]|volume=142|pages=414–419|doi=10.1086/148306}}</ref><ref>The history is given in {{cite book|last=Peebles|first=P. J. E|year=1993|title=Principles of Physical Cosmology|pages=139–148|publisher=[[Princeton University Press]]|isbn=0691019339}}</ref> A meeting between the Princeton and Crawford Hill groups determined that the antenna temperature was indeed due to the microwave background. Penzias and Wilson received the 1978 [[Nobel Prize in Physics]] for their discovery.<ref>{{cite web|year=1978|title=The Nobel Prize in Physics 1978|url=http://nobelprize.org/nobel_prizes/physics/laureates/1978/|publisher=[[Nobel Foundation]]|accessdate=2009-01-08}}</ref>