Editing Multiverse (section)

== Search for evidence ==
In the 1990s, after recent works of fiction about the concept gained popularity, scientific discussions about the multiverse and [[Scientific journal|journal]] articles about it gained prominence.<ref>{{Cite web |last=Romeo |first=Jess |date=2022-01-07 |title=The Real Science of the Multiverse |url=https://daily.jstor.org/the-real-science-of-the-multiverse/ |access-date=2023-07-15 |website=JSTOR Daily |publisher=[[JSTOR]] |language=en-US}}</ref>

Around 2010, scientists such as Stephen M. Feeney analyzed [[Wilkinson Microwave Anisotropy Probe]] (WMAP) data and claimed to find evidence suggesting that this universe collided with other (parallel) universes in the distant past.<ref>{{cite web|title=Astronomers Find First Evidence Of Other Universe|url=https://www.technologyreview.com/s/421999/astronomers-find-first-evidence-of-other-universes/|publisher=technologyreview.com|access-date=12 October 2013|date=13 December 2010}}</ref><ref>{{cite web |author=Tegmark |first1=Max |last2=Vilenkin |first2=Alexander |date=19 July 2011 |title=The Case for Parallel Universes |url=https://www.scientificamerican.com/article/multiverse-the-case-for-parallel-universe/ |access-date=12 October 2013 |website=[[Scientific American]]}}</ref><ref>{{cite web|title=Is Our Universe Inside a Bubble? First Observational Test of the 'Multiverse'|url=https://www.sciencedaily.com/releases/2011/08/110803102844.htm|work=Science Daily|publisher=sciencedaily.com|access-date=12 October 2013|date=3 August 2011}}</ref> However, a more thorough analysis of data from the WMAP and from the [[Planck (spacecraft)|Planck satellite]], which has a resolution three times higher than WMAP, did not reveal any statistically significant evidence of such a [[bubble universe]] collision.<ref name="Feeney">{{cite journal |title=First observational tests of eternal inflation: Analysis methods and WMAP 7-year results  |journal=Physical Review D |volume=84 |issue=4 |page=43507  |date=2011 |arxiv=1012.3667 |last1=Feeney|first1=Stephen M. |display-authors=1 |bibcode=2011PhRvD..84d3507F |last2=Johnson |first2=Matthew C.|last3=Mortlock |first3=Daniel J.  |last4=Peiris  |first4=Hiranya V.  |doi=10.1103/PhysRevD.84.043507  |s2cid=43793857 }}</ref><ref name="Feeney2">{{cite journal|title=First observational tests of eternal inflation |journal=Physical Review Letters |volume=107 |issue=7 |page=071301 |date=2011 |arxiv=1012.1995 |author=Feeney |display-authors=etal   |bibcode = 2011PhRvL.107g1301F |doi = 10.1103/PhysRevLett.107.071301 |pmid=21902380 |s2cid=23560957 }}. {{Cite journal|arxiv=1309.4060|last1=Bousso|first1=Raphael|title=Inflation after False Vacuum Decay: Observational Prospects after Planck|journal=Physical Review D|volume=91|issue=8|page=083527|last2=Harlow|first2=Daniel|last3=Senatore|first3=Leonardo|year=2015|doi=10.1103/PhysRevD.91.083527|bibcode = 2015PhRvD..91h3527B |s2cid=118488797}}</ref> In addition, there was no evidence of any gravitational pull of other universes on ours.<ref>{{Cite journal|arxiv=1303.5090 |title= Planck intermediate results. XIII. Constraints on peculiar velocities |journal=Astronomy & Astrophysics |volume=561 |pages=A97 |date=2013-03-20 |last1=Collaboration |first1=Planck |last2= Ade |first2=P. A. R. |last3= Aghanim |first3=N.|author3-link=Nabila Aghanim |last4= Arnaud |first4=M. |last5= Ashdown |first5=M. |last6= Aumont |first6=J. |last7= Baccigalupi |first7=C. |last8= Balbi |first8=A. |last9= Banday |first9=A. J. |last10= Barreiro |first10=R. B. |last11= Battaner |first11=E. |last12= Benabed |first12=K. |last13= Benoit-Levy |first13=A. |last14= Bernard |first14=J. -P. |last15= Bersanelli |first15=M. |last16= Bielewicz |first16=P. |last17= Bikmaev |first17=I. |last18= Bobin |first18=J. |last19= Bock |first19=J. J. |last20= Bonaldi |first20=A. |last21= Bond |first21=J. R. |last22= Borrill |first22=J. |last23= Bouchet |first23=F. R. |last24= Burigana |first24=C. |last25= Butler |first25=R. C. |last26= Cabella |first26=P. |last27= Cardoso |first27=J. -F. |last28= Catalano |first28=A. |last29= Chamballu |first29=A. |last30= -Y Chiang |first30=L. |display-authors=29 |doi=10.1051/0004-6361/201321299 |bibcode = 2014A&A...561A..97P |s2cid= 2745526 }}</ref><ref>{{cite news|title=Blow for 'dark flow' in Planck's new view of the cosmos|url=https://www.newscientist.com/article/dn23340-blow-for-dark-flow-in-plancks-new-view-of-the-cosmos|access-date=10 March 2014|newspaper=[[New Scientist]]|date=3 April 2013}}</ref>

In 2015, an astrophysicist may have found evidence of alternate or parallel universes by looking back in time to a time immediately after the [[Big Bang]], although it is still a matter of debate among physicists.<ref name="www.usatoday.com">{{cite web |title=Study may have found evidence of alternate, parallel universes |url=http://www.usatoday.com/story/tech/2015/11/03/alternate-universes-discovered/75102502/ |publisher=www.usatoday.com}}<!-- auto-translated by Module:CS1 translator --> por Doyle Rice, ''[[USA Today]]'' (2015).</ref> Dr. Ranga-Ram Chary, after analyzing the [[Cosmic microwave background|cosmic radiation spectrum]], found a signal 4,500 times brighter than it should have been, based on the number of [[Proton|protons]] and [[Electron|electrons]] scientists believe existed in the very early universe. This signal—an emission line that arose from the formation of atoms during the era of recombination—is more consistent with a universe whose ratio of matter particles to photons is about 65 times greater than our own. There is a 30% chance that this signal is noise, and not really a signal at all; however, it is also possible that it exists because a parallel universe dumped some of its matter particles into our universe. If additional protons and electrons had been added to our universe during recombination, more atoms would have formed, more photons would have been emitted during their formation, and the signature line that arose from all of these emissions would be greatly enhanced. Chary himself is skeptical:{{quotation|text=Many other regions beyond our observable universe would exist with each such region governed by a different set of physical parameters than the ones we have measured for our universe.<ref name="www.usatoday.com"/>|author=Ranga-Ram Chary|title=''USA Today''|source=}}

Chary also noted:<ref name="phys.org">{{cite web |title=Cosmologist thinks a strange signal may be evidence of a parallel universe |url=http://phys.org/news/2015-11-cosmologist-strange-evidence-parallel-universe.html#jCp |publisher=phys.org}}<!-- auto-translated by Module:CS1 translator --> por Vanessa Janek, "Universe Today" (2015).</ref>{{quotation|text=Unusual claims like evidence for alternate universes require a very high burden of proof.<ref name="phys.org"/>|author=Ranga-Ram Chary|title="Universe Today"|source=}}

The signature that Chary has isolated may be a consequence of incoming light from distant [[Galaxy|galaxies]], or even from clouds of dust surrounding our own galaxy.<ref name="phys.org"/>