a st ro - p h / 99 06 46 3 v 2 8 J ul 1 99 9 The Cosmic Triangle : Assessing the State of the Universe
نویسندگان
چکیده
The cosmic triangle is introduced as a way of representing the past, present, and future status of the universe. Our current location within the cosmic triangle is determined by the answers to three questions: How much matter is in the universe? Is the expansion rate slowing down or speeding up? And, is the universe flat? A review of recent observations suggests a universe that is lightweight (matter density about one-third the critical value), is accelerating, and is flat. The acceleration implies the existence of cosmic dark energy that overcomes the gravitational self-attraction of matter and causes the expansion to speed up.
منابع مشابه
X iv : a st ro - p h / 99 06 46 3 v 1 2 9 Ju n 19 99 The Cosmic Triangle : Assessing the State of the Universe
The cosmic triangle is introduced as a way of representing the past, present, and future status of the universe. Our current location within the cosmic triangle is determined by the answers to three questions: How much matter is in the universe? Is the expansion rate slowing down or speeding up? And, is the universe flat? A review of recent observations suggests a universe that is lightweight (...
متن کاملar X iv : a st ro - p h / 99 06 46 3 v 3 1 4 Ju l 1 99 9 The Cosmic Triangle : Assessing the State of the Universe
The cosmic triangle is introduced as a way of representing the past, present, and future status of the universe. Our current location within the cosmic triangle is determined by the answers to three questions: How much matter is in the universe? Is the expansion rate slowing down or speeding up? And, is the universe flat? A review of recent observations suggests a universe that is lightweight (...
متن کاملar X iv : a st ro - p h / 99 06 46 3 v 4 1 A ug 1 99 9 The Cosmic Triangle : Assessing the State of the Universe
The cosmic triangle is introduced as a way of representing the past, present, and future status of the universe. Our current location within the cosmic triangle is determined by the answers to three questions: How much matter is in the universe? Is the expansion rate slowing down or speeding up? And, is the universe flat? A review of recent observations suggests a universe that is lightweight (...
متن کاملar X iv : a st ro - p h / 98 07 09 3 v 1 9 J ul 1 99 8 HOW SMOOTH IS THE UNIVERSE ON LARGE SCALES ?
We review cosmological inference from optical and radio galaxy surveys, the X-Ray Background and the Cosmic Microwave Background. We focus on three topics: (i) First results from the 2dF galaxy redshift survey; (ii) Estimation of cosmological parameters by joint analysis of redshift surveys and CMB data; and (iii) The validity of the Cosmological Principle, and constraints on the fractal dimens...
متن کاملar X iv : a st ro - p h / 99 04 06 2 v 1 5 A pr 1 99 9 CBR Polarization Experiments
A handful of new experiments aimed at measuring the asyet-undetected polarization of the cosmic background radiation (CBR) are described, with somewhat more detail given for three experiments with which the authors are associated.
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