890:
constant, that is, the farther an object is, the less light we receive, but its apparent area diminishes as well, so the light received divided by the apparent area should be constant. In an expanding universe, the surface brightness diminishes with distance. As the observed object recedes, photons are emitted at a reduced rate because each photon has to travel a distance that is a little longer than the previous one, while its energy is reduced a little because of increasing redshift at a larger distance. On the other hand, in an expanding universe, the object appears to be larger than it really is, because it was closer to us when the photons started their travel. This causes a difference in surface brilliance of objects between a static and an expanding
Universe. This is known as the
928:
882:
570:
47:
1232:... gravitational analogue of the Compton effect It is easy to see that the above redshift should broaden these absorption lines asymmetrically toward the red. If these lines can be photographed with a high enough dispersion, the displacement of the center of gravity of the line will give the redshift independent of the velocity of the system from which the light is emitted.
582:
1320:, but ten months later, in the same journal, such tired light models were shown to be inconsistent with extant observations. As cosmological measurements became more precise and the statistics in cosmological data sets improved, tired light proposals ended up being falsified, to the extent that the theory was described in 2001 by science writer
1240:
recessional-velocity based theory. He writes, referring to sources of light within our galaxy: "It is especially desirable to determine the redshift independent of the proper velocities of the objects observed". Subsequent to this, astronomers have patiently mapped out the three-dimensional velocity-position
889:
By the 1990s and on into the twenty-first century, a number of falsifying observations have shown that "tired light" hypotheses are not viable explanations for cosmological redshifts. For example, in a static universe with tired light mechanisms, the surface brightness of stars and galaxies should be
1691:
Goldhaber, G.; Groom, D. E.; Kim, A.; Aldering, G.; Astier, P.; Conley, A.; Deustua, S. E.; Ellis, R.; Fabbro, S.; Fruchter, A. S.; Goobar, A.; Hook, I.; Irwin, M.; Kim, M.; Knop, R. A.; Lidman, C.; McMahon, R.; Nugent, P. E.; Pain, R.; Panagia, N.; Pennypacker, C. R.; Perlmutter, S.; Ruiz-Lapuente,
1223:
One might expect a shift of spectral lines due to the difference of the static gravitational potential at different distances from the center of a galaxy. This effect, of course, has no relation to the distance of the observed galaxy from our own system and, therefore, cannot provide any explanation
829:
has noted "Zwicky’s hypothesis was the best known and most elaborate alternative to the expanding universe, but it was far from the only one. More than a dozen physicists, astronomers and amateur scientists proposed in the 1930s tired-light ideas having in common the assumption of nebular photons
1263:
both incline to the opinion, however, that if the red-shift is not due to recessional motion, its explanation will probably involve some quite new physical principles use of a static
Einstein model of the universe, combined with the assumption that the photons emitted by a nebula lose energy on
741:
realized that this correlation could fit non-static solutions to the equations of
Einstein's theory of gravity, the Friedmann–Lemaître solutions. However Lemaître's article was appreciated only after Hubble's publication of 1929. The universal redshift-distance relation in this solution is
730:) generally exhibited redshift rather than blueshifts independent of where they were located. Since the relation holds in all directions it cannot be attributed to normal movement with respect to a background which would show an assortment of redshifts and blueshifts. Everything is moving
935:
is an image of galaxies that are in excess of 10 billion light years away. If tired light was a correct explanation, these galaxies would appear blurred in comparison to closer galaxies. That they do not rules out the suggestion that scattering processes are causing the redshift-distance
873:
that precisely specifies the state and evolution of the universe. Although the proposals of "tired light cosmologies" are now more-or-less relegated to the dustbin of history, as a completely alternative proposal tired-light cosmologies were considered a remote possibility worthy of some
1239:
Zwicky also notes, in the same paper, that according to a tired light model a distance-redshift relationship would necessarily be present in the light from sources within our own galaxy (even if the redshift would be so small that it would be hard to measure), that do not appear under a
1205:
on those free electrons But then the light scattered in all directions would make the interstellar space intolerably opaque which disposes of the above explanation. it is evident that any explanation based on a scattering process like the
Compton effect or the
1268:
These conditions became almost impossible to meet and the overall success of general relativistic explanations for the redshift-distance relation is one of the core reasons that the Big Bang model of the universe remains the cosmology preferred by researchers.
1295:
three months later in response to this suggestion heavily criticizing the approach, "No generally accepted physical mechanism has been proposed for this loss." Still, until the so-called "Age of
Precision Cosmology" was ushered in with results from the
663:
have been observed—these effects should not be present if the cosmological redshift was due to any tired light scattering mechanism. Despite periodic re-examination of the concept, tired light has not been supported by observational tests and remains a
1214:
This expected "blurring" of cosmologically distant objects is not seen in the observational evidence, though it would take much larger telescopes than those available at that time to show this with certainty. Alternatively, Zwicky proposed a kind of
973:, in his paper proposing these models investigated a number of redshift explanations, ruling out some himself. The simplest form of a tired light theory assumes an exponential decrease in photon energy with distance traveled:
864:
developed in the late twentieth century and the associated data became more numerous and accurate, the Big Bang emerged as the cosmological theory most supported by the observational evidence, and it remains the accepted
1276:
proposed a redshift as "the result of loss of energy by observed photons traversing a radiation field". which was cited and argued for as an explanation for the redshift-distance relation in a 1962 astrophysics theory
1051:
1745:
Lubin, Lori M.; Sandage, Allan (2001). "The Tolman
Surface Brightness Test for the Reality of the Expansion. IV. A Measurement of the Tolman Signal and the Luminosity Evolution of Early-Type Galaxies".
171:
856:, both of which relied on the general relativistic expansion of the universe of the FRW metric. Through the middle of the twentieth century, most cosmologists supported one of these two
2240:
Measurements of the cosmic microwave background put the theory firmly on the fringe of physics 30 years ago; still, scientists sought more direct proofs of the expansion of the cosmos.
2046:"Our Age of Precision Cosmology". Proceedings of the 2002 International Symposium on Cosmology and Particle Astrophysics (CosPA 02) Taipei, Taiwan, 31 May – 2 June 2002 (pp. 314–325)
644:, who suggested that if photons lost energy over time through collisions with other particles in a regular way, the more distant objects would appear redder than more nearby ones.
860:, but there were a few scientists, especially those who were working on alternatives to general relativity, who worked with the tired light alternative. As the discipline of
1264:
their journey to the observer by some unknown effect, which is linear with distance, and which leads to a decrease in frequency, without appreciable transverse deflection.
542:
919:
of general relativity. Such theories are sometimes referred to as "tired-light cosmologies", though not all authors are necessarily aware of the historical antecedents.
1187:
1156:
1129:
1082:
1692:
P.; Schaefer, B.; Walton, N. A.; York, T.; The
Supernova Cosmology Project (2001). "Timescale Stretch Parameterization of Type Ia Supernova B-band Light Curves".
1102:
1308:
proposing "photon decay" in a curved spacetime that was five months later criticized in the same journal as being wholly inconsistent with observations of the
1244:
for the galaxy and found the redshifts and blueshifts of galactic objects to accord well with the statistical distribution of a spiral galaxy, eliminating the
612:
734:
from the Milky Way galaxy. Hubble's contribution was to show that the magnitude of the redshift correlated strongly with the distance to the galaxies.
1382:
978:
1304:, tired light models could occasionally get published in the mainstream journals, including one that was published in the February 1979 edition of
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2268:
1868:
1816:
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1538:
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that do not have an expanding universe in them need an alternative to explain the correspondence between redshift and distance that is
1634:
555:
1528:
1389:
2101:
Beckers, J. M.; Cram, L. E. (July 1979). "Use of the solar limb effect to test photon decay and cosmological redshift theories".
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906:
188:
901:. They often refer to age and distance to objects in terms of redshift rather than years or light-years. In such a scale, the
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264:
818:
703:
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116:
1236:
Such broadening of absorption lines is not seen in high-redshift objects, thus falsifying this particular hypothesis.
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598:
574:
121:
1316:. In 1986 a paper claiming tired light theories explained redshift better than cosmic expansion was published in the
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320:
128:
73:
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interacting with intergalactic matter to which they transferred part of their energy." Kragh noted in particular
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711:
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637:
166:
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835:
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100:
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In general, any "tired light" mechanism must solve some basic problems, in that the observed redshift must:
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303:
183:
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1309:
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that in those studies favors the expanding universe hypothesis and rules out static tired light models.
508:
310:
252:
1554:
Kragh, Helge (2019). "Alternative
Cosmological Theories". In Kragh, Helge; Longair, Malcolm S. (eds.).
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The Tolman surface brightness test rules out the tired light explanation for the cosmological redshift.
801:
by interaction with matter or other photons, or by some novel physical mechanism. Since a decrease in
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2010:
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1932:
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1804:
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1711:
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866:
521:
493:
315:
1838:
1587:
Wilson, O. C. (1939). "Possible
Applications of Supernovae to the Study of the Nebular Red Shifts".
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1983:
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consideration in cosmology texts well into the 1980s, though it was dismissed as an unlikely and
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At the same time, other explanations were proposed that did not concord with general relativity.
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38:
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1885:
1864:
1812:
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898:
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but not general relativity that there was a giant explosion that could explain redshifts (see
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503:
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2018:
1975:
1940:
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Zwicky's proposals were carefully presented as falsifiable according to later observations:
870:
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from an object toward lower energies and frequencies, associated with the phenomenon of the
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of light would blur the images of distant objects more than what is seen. Additionally, the
586:
398:
388:
373:
224:
93:
1563:
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30 years ago; still, scientists sought more direct proofs of the expansion of the cosmos".
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2014:
1971:
1936:
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1808:
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1715:
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1600:
1485:
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2001:
Alpher, R. A. (1962). "Laboratory Test of the Finlay-Freundlich Red Shift
Hypothesis".
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458:
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1944:
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attributable to the effect an expanding universe has on a photon traveling on a null
723:
719:
656:
483:
468:
368:
2132:
1888:(November 1935). "Two Methods of Investigating the Nature of the Nebular Redshift".
1731:
2087:
2043:
2030:
1987:
1881:
1252:
1210:, etc., will be in a hopeless position regarding the good definition of the images.
1207:
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is a large constant characterizing the "resistance of the space". To correspond to
970:
782:
691:
641:
488:
463:
438:
423:
279:
1409:
Peebles, P. J. E. (1998). "The Standard Cosmological Model". In Greco, M. (ed.).
1363:
636:. These models have been proposed as alternatives to the models that involve the
1622:
1241:
911:
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Redshift is directly observable and used by cosmologists as a direct measure of
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778:
236:
229:
1923:
Finlay-Freundlich, E. (1954). "Red-Shifts in the Spectra of Celestial Bodies".
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1359:
806:
648:
478:
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compared recessional redshift with a non-recessional one, writing that they
951:
428:
1513:
1494:
17:
1201:... light coming from distant nebulae would undergo a shift to the red by
1760:
1706:
1436:
The light/dark universe: light from galaxies, dark matter and dark energy
1419:
902:
857:
846:
810:
794:
747:
699:
677:
629:
161:
63:
56:
969:
A number of tired light mechanisms have been suggested over the years.
1979:
821:
with the distance of the source. The term "tired light" was coined by
46:
2146:
LaViolette, P. A. (April 1986). "Is the universe really expanding?".
2124:
2079:
2022:
1190:
802:
790:
786:
754:, though relative velocities need to be handled with more care since
727:
695:
2205:
2167:
1909:
1777:
1723:
1676:
1651:
1608:
845:
Tired light mechanisms were among the proposed alternatives to the
750:). In this formulation, there was still an analogous effect to the
632:
mechanisms that was proposed as an alternative explanation for the
1958:
Brown, P. F. (1962). "The Case for an Exponential Red Shift Law".
926:
880:
785:
proposed a "tired light" mechanism in 1929. Zwicky suggested that
781:
could explain the redshift-distance correlation. Along this line,
687:
2184:(February 1987). "Source counts in the chronometric cosmology".
1297:
1046:{\displaystyle E(x)=E_{0}\exp \left(-{\frac {x}{R_{0}}}\right)}
1470:"On the Redshift of Spectral Lines Through Interstellar Space"
1197:
could account for the scale normalization of the above model:
2056:
Crawford, D. F. (1979). "Photon Decay in Curved Space-time".
1287:
physics professor P. F. Browne. The pre-eminent cosmologist
690:
was an idea that came about due to the observation made by
1530:
The Enigmatic Photon: Theory and Practice of the B3 Field
1193:. For example, Zwicky considered whether an integrated
1131:
is the energy of the photon at the source of light, and
659:
of cosmological sources, and a thermal spectrum of the
1556:
The Oxford Handbook of the History of Modern Cosmology
726:
observed that these objects (now known to be separate
1168:
1137:
1110:
1090:
1061:
981:
825:in the early 1930s as a way to refer to this idea.
1181:
1150:
1123:
1096:
1076:
1045:
950:follow the detailed Hubble relation observed with
944:admit the same measurement in any wavelength-band
653:surface brightness of galaxies evolving with time
1434:Overduin, James Martin; Wesson, Paul S. (2008).
1219:explanation for the redshift distance relation:
1474:Proceedings of the National Academy of Sciences
1261:
1230:
1221:
1199:
737:Basing on Slipher's and Hubble's data, in 1927
1527:Evans, Myron W.; Vigier, Jean-Pierre (1996).
606:
8:
1801:The Routledge Companion to the New Cosmology
640:. The concept was first proposed in 1929 by
1799:Barrow, John D. (2001). Peter Coles (ed.).
1438:. World Scientific Publishing. p. 10.
1411:Rencontres de Physique de la Vallee d'Aosta
1355:
1353:
1652:"Test of the Expanding Universe Postulate"
1224:of the phenomenon discussed in this paper.
613:
599:
213:
87:
45:
29:
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1650:Geller, M. J.; Peebles, P. J. E. (1972).
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1643:
1503:
1493:
1418:
1404:
1402:
1383:University of California at Santa Barbara
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1167:
1142:
1136:
1115:
1109:
1089:
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1030:
1021:
1001:
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682:Non-standard cosmology § Tired light
27:Class of hypothetical redshift mechanisms
2224:"'Tired-Light' Hypothesis Gets Re-Tired"
1834:"Prospecting for C IV at high redshifts"
1463:
1461:
1459:
1457:
1455:
1084:is the energy of the photon at distance
878:proposal by mainstream astrophysicists.
769:proposed an explanation compatible with
1349:
905:corresponds to a redshift of infinity.
244:
216:
108:
37:
1377:
1375:
1373:
805:corresponds to an increase in light's
1925:Proceedings of the Physical Society A
647:Zwicky acknowledged that any sort of
7:
1629:. (1980) W. H. Freeman and Company.
1564:10.1093/oxfordhb/9780198817666.013.4
758:can be defined in different ways in
1832:Newton, Elisabeth (27 April 2011).
341:2dF Galaxy Redshift Survey ("2dF")
25:
1381:Tommaso Treu, Lecture slides for
965:of cosmologically distant events.
556:Timeline of cosmological theories
321:Cosmic Background Explorer (COBE)
1251:Following after Zwicky in 1935,
580:
569:
568:
1364:Errors in Tired Light Cosmology
907:Alternative theories of gravity
336:Sloan Digital Sky Survey (SDSS)
189:Future of an expanding universe
2274:Physical cosmological concepts
1863:. Princeton University Press,
1071:
1065:
991:
985:
892:Tolman surface brightness test
809:, this effect would produce a
746:(also known as a "light-like"
634:redshift-distance relationship
551:History of the Big Bang theory
347:Wilkinson Microwave Anisotropy
1:
706:. Redshift is a shift in the
543:Discovery of cosmic microwave
194:Ultimate fate of the universe
2269:Obsolete theories in physics
1621:See, for example, p. 397 of
661:cosmic microwave background
628:is a class of hypothetical
311:Black Hole Initiative (BHI)
2290:
1945:10.1088/0370-1298/67/2/114
1803:. Routledge. p. 308.
1104:from the source of light,
675:
74:Chronology of the universe
1859:Binney & Merrifield:
1694:The Astrophysical Journal
1656:The Astrophysical Journal
1589:The Astrophysical Journal
923:Specific falsified models
712:electromagnetic radiation
638:expansion of the universe
167:Expansion of the universe
1748:The Astronomical Journal
1533:. Springer. p. 29.
1324:as being "firmly on the
1285:University of Manchester
1248:component as an effect.
836:William Duncan MacMillan
777:). Others proposed that
331:Planck space observatory
117:Gravitational wave (GWB)
1300:space probe and modern
1274:Erwin Finlay-Freundlich
933:Hubble Ultra Deep Field
862:observational cosmology
184:Inhomogeneous cosmology
1495:10.1073/pnas.15.10.773
1310:gravitational redshift
1266:
1234:
1226:
1212:
1183:
1152:
1125:
1098:
1078:
1047:
937:
886:
702:proportional to their
2186:Astrophysical Journal
2148:Astrophysical Journal
1890:Astrophysical Journal
1385:Astrophysics course.
1318:Astrophysical Journal
1184:
1182:{\displaystyle R_{0}}
1153:
1151:{\displaystyle R_{0}}
1126:
1124:{\displaystyle E_{0}}
1099:
1079:
1048:
956:accelerating universe
930:
884:
760:an expanding universe
672:History and reception
275:Large-scale structure
253:Shape of the universe
1272:In the early 1950s,
1189:must be several giga
1166:
1135:
1108:
1088:
1077:{\displaystyle E(x)}
1059:
979:
947:not exhibit blurring
793:as they travel vast
587:Astronomy portal
545:background radiation
522:List of cosmologists
2198:1987ApJ...313..551W
2160:1986ApJ...301..544L
2117:1979Natur.280..255B
2072:1979Natur.277..633C
2015:1962Natur.196..367A
1972:1962Natur.193.1019B
1966:(4820): 1019–1021.
1937:1954PPSA...67..192F
1902:1935ApJ....82..302H
1809:2001rcnc.book.....C
1770:2001AJ....122.1084L
1716:2001ApJ...558..359G
1668:1972ApJ...174....1G
1601:1939ApJ....90..634W
1486:1929PNAS...15..773Z
1468:Zwicky, F. (1929).
1338:Dispersion (optics)
961:explain associated
832:John Quincy Stewart
287:Structure formation
179:Friedmann equations
69:Age of the universe
33:Part of a series on
1886:Tolman, Richard C.
1861:Galactic Astronomy
1392:2010-06-23 at the
1291:wrote a letter to
1289:Ralph Asher Alpher
1246:intrinsic redshift
1217:Sachs–Wolfe effect
1179:
1148:
1121:
1094:
1074:
1043:
938:
887:
789:might slowly lose
779:systematic effects
771:special relativity
744:spacetime interval
326:Dark Energy Survey
270:Large quasar group
39:Physical cosmology
2111:(5719): 255–256.
2066:(5698): 633–635.
2009:(4852): 367–368.
1980:10.1038/1931019a0
1869:978-0-691-02565-0
1818:978-0-415-24312-4
1573:978-0-19-881766-6
1540:978-0-7923-4044-7
1445:978-981-283-441-6
1326:fringe of physics
1097:{\displaystyle x}
1036:
917:expanding metrics
668:in astrophysics.
623:
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294:
293:
136:
135:
16:(Redirected from
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2222:(28 June 2001).
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2125:10.1038/280255a0
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2080:10.1038/277633a0
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2044:Smoot, George S.
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2023:10.1038/196367b0
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1761:astro-ph/0106566
1754:(3): 1084–1103.
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1707:astro-ph/0104382
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1312:observed in the
1302:redshift surveys
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739:Georges Lemaître
696:distant galaxies
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572:
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265:Galaxy formation
225:Lambda-CDM model
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206:Components
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1480:(10): 773–779.
1467:
1466:
1453:
1446:
1433:
1432:
1428:
1408:
1407:
1400:
1394:Wayback Machine
1380:
1371:
1358:
1351:
1346:
1334:
1169:
1164:
1163:
1162:, the constant
1138:
1133:
1132:
1111:
1106:
1105:
1086:
1085:
1057:
1056:
1026:
1017:
1013:
997:
977:
976:
925:
871:parametrization
869:with a current
867:consensus model
799:static universe
718:. Observers of
710:of the emitted
684:
674:
619:
581:
579:
561:
560:
547:
544:
537:
535:Subject history
527:
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363:
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351:
348:
306:
296:
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258:Galaxy filament
211:
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150:
145:Expansion
138:
137:
122:Microwave (CMB)
101:Nucleosynthesis
85:
28:
23:
22:
15:
12:
11:
5:
2287:
2285:
2277:
2276:
2271:
2266:
2261:
2259:Fringe physics
2251:
2250:
2245:
2244:
2211:
2206:10.1086/164996
2173:
2168:10.1086/163922
2138:
2093:
2048:
2036:
1993:
1950:
1931:(2): 192–193.
1915:
1910:10.1086/143682
1873:
1852:
1839:astrobites.org
1824:
1817:
1791:
1778:10.1086/322134
1737:
1724:10.1086/322460
1700:(1): 359–368.
1683:
1677:10.1086/151462
1639:
1614:
1609:10.1086/144134
1579:
1572:
1558:. p. 29.
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1398:
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1333:
1330:
1257:Richard Tolman
1203:Compton effect
1195:Compton effect
1176:
1172:
1145:
1141:
1118:
1114:
1093:
1073:
1070:
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948:
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924:
921:
840:Walther Nernst
823:Richard Tolman
819:proportionally
817:that increase
815:spectral lines
775:Milne universe
752:Doppler effect
720:spiral nebulae
716:Doppler effect
673:
670:
621:
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129:Neutrino (CNB)
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84:Early universe
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2220:Charles Seife
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2182:Wright, E. L.
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1882:Hubble, Edwin
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1635:0-7167-1812-X
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1360:Wright, E. L.
1356:
1354:
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1322:Charles Seife
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963:time dilation
960:
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899:lookback time
895:
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724:Vesto Slipher
721:
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657:time dilation
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58:
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48:
44:
43:
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36:
32:
31:
19:
2239:
2233:. Retrieved
2227:
2214:
2189:
2185:
2176:
2151:
2147:
2141:
2108:
2102:
2096:
2063:
2057:
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2006:
2002:
1996:
1963:
1959:
1953:
1928:
1924:
1918:
1893:
1889:
1876:
1860:
1855:
1843:. Retrieved
1837:
1827:
1800:
1794:
1751:
1747:
1740:
1697:
1693:
1686:
1659:
1655:
1627:The Big Bang
1626:
1617:
1592:
1588:
1582:
1555:
1549:
1529:
1522:
1477:
1473:
1435:
1429:
1410:
1362:
1317:
1305:
1292:
1278:
1271:
1267:
1262:
1253:Edwin Hubble
1250:
1238:
1235:
1231:
1227:
1222:
1213:
1208:Raman effect
1200:
1160:Hubble's law
1054:
975:
971:Fritz Zwicky
968:
939:
910:
896:
888:
875:
851:Steady State
844:
783:Fritz Zwicky
767:Edward Milne
764:
736:
731:
692:Edwin Hubble
685:
666:fringe topic
646:
642:Fritz Zwicky
625:
624:
349:Probe (WMAP)
283:
280:Reionization
261:
233:
207:
175:
158:
155:Hubble's law
146:
125:
97:
60:
2192:: 551–555.
2154:: 544–553.
1623:Joseph Silk
1242:phase space
912:sui generis
854:cosmologies
827:Helge Kragh
626:Tired light
304:Experiments
237:Dark matter
230:Dark energy
172:FLRW metric
109:Backgrounds
18:Tired Light
2253:Categories
2235:2016-06-03
1845:4 November
1344:References
1314:solar limb
954:data (see
807:wavelength
797:through a
676:See also:
649:scattering
384:Copernicus
362:Scientists
217:Components
1786:118897528
1625:'s book,
1283:paper by
1019:−
1011:
952:supernova
936:relation.
858:paradigms
795:distances
756:distances
700:redshifts
514:Zeldovich
414:Friedmann
389:de Sitter
316:BOOMERanG
245:Structure
210:Structure
94:Inflation
2133:43273035
1732:17237531
1514:16577237
1390:Archived
1332:See also
903:Big Bang
849:and the
847:Big Bang
811:redshift
748:geodesic
728:galaxies
722:such as
708:spectrum
704:distance
678:Redshift
630:redshift
575:Category
494:Suntzeff
454:Lemaître
404:Einstein
369:Aaronson
162:Redshift
64:Universe
57:Big Bang
2229:Science
2194:Bibcode
2156:Bibcode
2113:Bibcode
2088:4317887
2068:Bibcode
2031:4197527
2011:Bibcode
1988:4154001
1968:Bibcode
1933:Bibcode
1898:Bibcode
1896:: 302.
1805:Bibcode
1766:Bibcode
1712:Bibcode
1664:Bibcode
1597:Bibcode
1595:: 634.
1482:Bibcode
1191:parsecs
915:to the
787:photons
499:Sunyaev
484:Schmidt
474:Penzias
469:Penrose
444:Huygens
434:Hawking
419:Galileo
2131:
2104:Nature
2086:
2059:Nature
2029:
2003:Nature
1986:
1960:Nature
1867:
1815:
1784:
1730:
1633:
1570:
1537:
1512:
1505:522555
1502:
1442:
1306:Nature
1293:Nature
1280:Nature
1055:where
876:ad hoc
838:, and
803:energy
791:energy
686:Tired
573:
509:Wilson
504:Tolman
464:Newton
459:Mather
449:Kepler
439:Hubble
399:Ehlers
379:Alpher
374:Alfvén
282:
260:
232:
174:
157:
149:Future
124:
96:
59:
2264:Light
2129:S2CID
2084:S2CID
2027:S2CID
1984:S2CID
1782:S2CID
1756:arXiv
1728:S2CID
1702:arXiv
1662:: 1.
1415:arXiv
1387:p. 16
698:have
694:that
688:light
489:Smoot
479:Rubin
424:Gamow
409:Ellis
394:Dicke
1865:ISBN
1847:2023
1813:ISBN
1631:ISBN
1568:ISBN
1535:ISBN
1510:PMID
1440:ISBN
1298:WMAP
1255:and
931:The
732:away
680:and
429:Guth
2202:doi
2190:313
2164:doi
2152:301
2121:doi
2109:280
2076:doi
2064:277
2019:doi
2007:196
1976:doi
1964:193
1941:doi
1906:doi
1774:doi
1752:122
1720:doi
1698:558
1672:doi
1660:174
1605:doi
1560:doi
1500:PMC
1490:doi
1008:exp
813:in
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2070::
2033:.
2021::
2013::
1990:.
1978::
1970::
1947:.
1943::
1935::
1912:.
1908::
1900::
1871:.
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1821:.
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