What is the Universe made of? How old is it?
| dc.creator | Lineweaver, Charles H. | |
| dc.date | 1999-11-16 | |
| dc.date.accessioned | 2026-07-07T02:34:28Z | |
| dc.date.available | 2026-07-07T02:34:28Z | |
| dc.description | For the past 15 years most astronomers have assumed that 95% of the Universe was in some mysterious form of cold dark matter. They also assumed that the cosmological constant, Omega_Lambda, was Einstein's biggest blunder and could be ignored. However, recent measurements of the cosmic microwave background combined with other cosmological observations strongly suggest that 75% of the Universe is made of cosmological constant (vacuum energy), while only 20% is made of non-baryonic cold dark matter. Normal baryonic matter, the stuff most physicists study, makes up about 5% of the Universe. If these results are correct, an unknown 75% of the Universe has been identified. Estimates of the age of the Universe depend upon what it is made of. Thus, our new inventory gives us a new age for the Universe: 13.4 +/- 1.6 Gyr. | |
| dc.description | 15 pages including 8 figures, to be published in "The Australian and New Zealand Physicist" | |
| dc.identifier | https://arxiv.org/abs/astro-ph/9911294 | |
| dc.identifier | http://arxiv.org/abs/astro-ph/9911294 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/15254 | |
| dc.subject | Astrophysics | |
| dc.title | What is the Universe made of? How old is it? | |
| dc.type | text |