Many people send multiple emails per day to recap an important meeting, to relay an important update, or simply to contact someone. Writing a formal email in French can be a challenge. Updated: Apby Mylene in Guides and Tips ▪ They feel that a lot more data and theoretical study is required before we can pronounce a judgement on this matter of life and death! ( Nature, Vol 404, p955 and Physical Review Letters, Vol 84, p3523.Writing a Professional Email in French (Sample template included) Though promising, several other astronomers are hedging their bets as to whether this can be taken as the final word on the curvature and hence the fate of our universe. There is just enough matter in the universe to make it flat and avoid the big crunch! Another group that has independently analysed the data and come up with the same conclusions also supports their findings. The group has analysed the data obtained from the balloon flights and has concluded that the data best fits a flat universe. This can provide us with a clue to its curvature and density at that time. With these measurements of the CMBR, they can in a sense study the conditions prevailing when the universe was only 300,000 years old (compared to today when it is about 12-15 billion years old). Since the early universe is relatively simple, scientists think they have a pretty good idea of the mechanisms at work at that time. Their experiment has measured the radiation with a greater degree of accuracy, some 10-30 times more accurate than COBE. The experiment is more accurate than the COBE satellite-based experiment and consists of balloon measurements over the Antarctica.Ī Lange of Caltech and P de Bernardis of the University of Rome led a 36-member international team of scientists in the experiment. Now a new, more accurate map of the radiation has been provided by an experiment known as ‘Balloon Observations Of Millimetric Extragalactic Radiation and Geomagnetics’ (Boomerang). The COBE satellite provided a detailed map of the CMBR in 1992 and it has been extensively studied since then. The radiation is known as the Cosmic Microwave Background Radiation ( CMBR). The temperature of this radiation is 3° above absolute zero, that is, about –270° C. This remnant energy is in the microwave part of the spectrum and was first discovered in the mid-sixties by accident at the Bell Laboratories by Penzias and Wilson. Once this happened, the radiation energy escaped and has been cooling since. When it was about 300,000 years old, the protons and electrons cooled down enough to form neutral hydrogen atoms. The radiation energy was trapped inside such a sea, bouncing off the charged particles. The early universe was very hot and contained protons and electrons which were densely packed and had too much energy to form any stable structures like hydrogen. The current measurements are of the microwave radiation that bathes our universe and is supposed to be a remnant of very early times. Nevertheless, there have been some attempts by astronomers to get information regarding the curvature by using various tools like supernovae explosions and gravitational lenses. The fundamental reason being that to really explore the large-scale structure of our universe we need accurate measurements of regions very distant from the earth. To study the curvature of space is very difficult. Of course, the crunch, even if it comes will occur in billions of years! A flat universe on the other hand has no such end. Such a universe will ultimately implode to a crunch. If the universe is curved positively, that is, in some senses like a sphere (in 4 dimensions) then present theories imply that it contains enough mass to halt the expansion of the universe and force it to contract. A flat universe is more like what we are used to in our lives.Īnother strange thing about cosmology, as we understand it today, is that the curvature is intimately linked with the fate of the universe. This has bizarre, non-commonsense implications for instance, if we travel long enough we come back to the same point. When we say that the universe is curved, we are talking about the curvature of space itself. This result if true will have a profound impact on the standard model of cosmology.Ĭurvature in the universe is not like what we are used to in our everyday world. Now a group of researchers have claimed that the universe is flat. There have been a spate of experiments in the recent past, which provide a clue to this fundamental query. Is our universe ‘flat’ or is it curved? If it is curved, is it ‘open’ or ‘closed’? These questions are of paramount importance for the ultimate fate of the universe we live in. One of the most tantalising questions in cosmology concerns the curvature of the universe.
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