The DOI matches its Crossref record; 5 of the 5 references it cites were found in a registry or an index.
Difficulties with Inflationary Cosmology a
Overview
Integrity signals
Registry
Cites
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Verification
Claims the paper makes
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
In the citing paper
“Penrose suggests a greatest lower bound on the allowed entropy of our observable universe by calculating what the entropy would be if all of the matter were put into one gigantic black hole, obtaining the famous number 10 122 .”
From In What Sense Is the Early Universe Fine-Tuned? (2014) · cites this paper as [1]
In the citing paper
“Penrose has famously characterized the fine-tuning problem in these terms, emphasizing how small the entropy of the early universe was compared to the current entropy, and how small that is compared to how large the entropy could be [1].”
From In What Sense Is the Early Universe Fine-Tuned? (2014) · cites this paper as [1]
In the citing paper
“a patch of spacetime ready to begin inflating has an enormously lower entropy than the (still quite low-entropy) homogeneous plasma into which it evolves [1, 2].”
From In What Sense Is the Early Universe Fine-Tuned? (2014) · cites this paper as [1]
Citations
Cites
Particle creation by black holes
Hawking, S. W. (1975) · Communications In Mathematical Physics · doi:10.1007/bf02345020 · Cited by 13,106
Inflationary universe: A possible solution to the horizon and flatness problems
Guth, A. H. (1981) · Physical Review D · doi:10.1103/physrevd.23.347 · Cited by 9,983
Linde, A. D. (1982) · Physics Letters B · doi:10.1016/0370-2693(82)91219-9 · Cited by 6,405
Cosmology for Grand Unified Theories with Radiatively Induced Symmetry Breaking
Albrecht, A., & Steinhardt, P. J. (1982) · Physical Review Letters · doi:10.1103/physrevlett.48.1220 · Cited by 4,981
First-order phase transition of a vacuum and the expansion of the Universe
Sato, K. (1981) · Monthly Notices of the Royal Astronomical Society · doi:10.1093/mnras/195.3.467 · Cited by 1,792
Flagged first, then by citations
Research works printed but not linked: 19
- Gliner E. B., 1965, Sov. Phys. JETP, 22, 378
- Guth A. H., 1981, Phys. Rev., 23, 347
- BÖrner G., 1988, The Early Universe—Facts and Fiction
- Penrose R., 1986, Book review of The Very Early Universe
- 10.1090/pspum/048/974344 · DOI
- Penrose R., 1979, General Relativity: An Einstein Centenary System
- Penrose R., 1981, Quantum Gravity 2
- 10.1093/oso/9780198519737.001.0001 · DOI · Paper page
- 10.1103/PhysRev.105.1089 · DOI
- Pirani F. A. E., 1961, Bull. Acad. Pol. Sci. Ser. Sci. Math. Astron. Phys., 9, 543
- 10.1098/rspa.1962.0206 · DOI
- Penrose R., 1966, Perspectives in Geometry and Relativity
- Turner M. S., 1987, General Relativity and Gravitation—Proceedings of the 11th International Conference on GRG, 238
- Davies P. C. W., 1974, The Physics of Time Asymmetry
- Hartle J. B., 1983, Phys. Rev., 31, 1777
- 10.1086/149448 · DOI
- 10.1103/PhysRevLett.22.1071 · DOI · Paper page
- 10.1080/00018737000101171 · DOI · Paper page
- Wheeler J. A., 1962, Geometrodynamics
Cited by
Sorted by citations
The Fine-Tuning of the Universe for Intelligent Life
Barnes, L. A. (2012) · Publications of the Astronomical Society of Australia · doi:10.1071/as12015 · Cited by 156
“The time asymmetry is a consequence of low entropy initial conditions, not the physics itself (Penrose 1989; Hollands & Wald 2002a).”
BackgroundCan the Universe create itself?
Gott, J. R., & Li, L.-X. (1998) · Physical Review D · doi:10.1103/physrevd.58.023501 · Cited by 127
In What Sense Is the Early Universe Fine-Tuned?
Carroll, S. M. (2014) · arXiv · doi:10.48550/arxiv.1406.3057 · Cited by 87
“This fine-tuning is often expressed in terms of entropy; a patch of spacetime ready to begin inflating has an enormously lower entropy than the (still quite low-entropy) homogeneous plasma into which it evolves [1, 2].”
BackgroundBlack holes, quantum theory and cosmology
Penrose, R. (2009) · Journal of Physics Conference Series · doi:10.1088/1742-6596/174/1/012001 · Cited by 42
Self-citationThe Big Bang and its Dark-Matter Content: Whence, Whither, and Wherefore
Penrose, R. (2018) · Foundations of Physics · doi:10.1007/s10701-018-0162-3 · Cited by 26
Self-citation
Metadata
- Authors
- PENROSE, R.
- Affiliations
- University of Oxford (GB)
- Corresponding author
- PENROSE, ROGER
- Venue
- Annals of the New York Academy of Sciences
- Publisher
- Wiley
- Published
- 1989-12
- Volume
- 571
- Issue
- 1
- Pages
- 249-264
- ISSN
- 0077-8923 (ISSN-L)
- 1749-6632
- OpenAlex
- W2129241506
- Cited by
- 165
- References
- 5
- Citations by year
- 2026: 9 · 2025: 8 · 2024: 13 · 2023: 12 · 2022: 10 · 2021: 9 · 2020: 6 · 2019: 7 · 2018: 15 · 2017: 5 · 2016: 5 · 2015: 10 · 2014: 8 · 2013: 8 · 2012: 4
- FWCI
- 2.74
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- Annals of the New York Academy of Sciences (publishedVersion)
- Topics
- Physical Sciences › Physics and Astronomy › Astronomy and Astrophysics › Cosmology and Gravitation Theories
- Physical Sciences › Physics and Astronomy › Astronomy and Astrophysics › Galaxies: Formation, Evolution, Phenomena
- Physical Sciences › Physics and Astronomy › Nuclear and High Energy Physics › Noncommutative and Quantum Gravity Theories
- Keywords
- cosmic inflation
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
Statistics and arithmetic are recomputed, not judged.
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