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Icarus physicists’
study upholds Einstein’s theory of relativity Under Einstein’s theory of relativity, nothing can travel faster than the speed of light. Otherwise, it would be possible to travel through time. Use social media
to help e-governance
This
Universe Trends |
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Icarus physicists’ study upholds Einstein’s theory of relativity A study
showing that sub-atomic particles can travel faster than the speed of light — thereby overturning more than 100 years of theoretical physics established by Albert Einstein — must be wrong, according to a rival team of physicists. Last September, scientists involved in the international Opera experiment said that a beam of neutrinos had arrived 60 billionths of a second faster than light would have travelled from the underground particle physics laboratory at Cern in Geneva to the Gran Sasso facility in Italy, 466 miles away. Over the weekend, the Opera scientists said they had repeated the experiment with minor modifications to the length of the particle beam to take into account a possible source of error. They said they found the same result — neutrinos that could travel faster than light. Under Einstein’s theory of relativity, nothing can travel faster than the speed of light. Otherwise, it would be possible to travel through time. Now a second group of scientists, part of the Icarus collaboration, has re-analysed the same beam and concluded that the particles could not have travelled faster than light speed without exhibiting a fall in energy levels, which was not detected. The re-analysis of the same neutrino beam by the Icarus group of physicists is the first serious study to question the “faster-than-light” findings that have astonished and confounded scientists in equal measure. Physicists involved in the Icarus collaboration have posted the new interpretation of the Opera’s results on a scientific website stating that the neutrinos would have lost discernible amounts of energy had they travelled faster than the “universal constant” of light speed — about 186,282 miles per second. As this was not the case, the particles could not have travelled faster than light, the Icarus team said. “Our results therefore refute a superluminal (faster than light speed) interpretation of the Opera result.” Tommaso Dorigo, a high-energy physicist at Cern who was not part of the Icarus group, said that the Icarus study was “very simple yet definitive” in refuting the almost heretical notion that sub-atomic particles could travel faster than light. “The Icarus result says that the difference between the speed of neutrinos and the speed of light cannot be as large as that seen by Opera, and is certainly smaller than that by three orders of magnitude and compatible with zero,” Dr Dorigo said on his blog. A definitive answer to the question of whether the Opera results hold water may have to wait until next year when scientists involved in the Minos consortium will carry out similar tests with American particle accelerators in Illinois. — The Independent
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Use social media to help e-governance SOCIAL media tools encompass a conglomeration of web-based technologies and services such as blogs, micro blogs (Twitter), social-sharing services (YouTube, Flickr, Last.fm, Stumble Upon), text messaging, email, discussion forums, collaborative editing tools (wikis), virtual worlds, and social networking services (Facebook, MySpace). While at the personal level, the utility and usage of such media is gaining rapid popularity, the use of such media for official purpose remain ambiguous. Today, social media tools are proving really helpful for various governments and many countries are adopting social media for many reasons. The US, for example, has adopted social media to share information within and across government agencies and above all to disseminate information to the public. The US government is using blogs to attract new audiences and to give a human face to government or using wikis to enhance community participation in decision making. Nowadays wide range of information can be disseminated. For many departments and services, mobile-based voice or text services and web-based presence can serve as an additional channel for information sharing. Governments around the world have been working to provide government information to public. This allows for more transparent governments over the long term, creating better informed, more demanding, future voters generating political capital because of accountability and transparency. Social media has been most effective for this purpose. However, Internet penetration is very low in India. There is a huge difference in communication styles with respect to government officials and citizens from different regions and even gender, which will make accumulation of information a difficult process. While citizen feedback, where the government takes inputs form citizens on different issues, will give a skewed picture if the government relies on social media, there is no doubt that among those who have Internet facility, social sites are a great draw. Internet users are becoming more and more active on social media which is really boosting crowd sourcing. Hence the association of existing e-governance projects with social media is fruitful. One of the ways for governments to ensure responsibility and accountability is by actively engaging with the public while making policies that impact them directly. One of the reasons cited for a high failure rate of e-governance projects across the world is the poor understanding of users’ needs and inability to involve citizens. It is, therefore, believed that citizen engagement would result in improved project conceptualisation and decision making because it would help the government to know the exact requirements of the public. In addition, public participation also increases awareness among citizens and gives them a sense of ownership of development processes by making them a part of it. Citizen participation is of great importance, especially in a democratic country like India, while social media tools have the potential to enhance citizen engagement. Finally, universal access and privacy and confidentiality issues as well as citizen-focused change must be considered throughout e-government development. Both in India as well as across the world, various government departments and agencies at federal, state and local government level are using this media. However, this is a dynamic and evolving area and continuous engagement and nimbleness of response to such an evolving scenario will determine the success of such efforts.
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This Universe How is the temperature at the Sun's centre, said to be about 15 million degrees Celsius, actually estimated? This is one of the most surprising methods, surprising and ingenious. I will go through this in some detail and hope that this would be enjoyable for those interested in such matters. We can measure the temperature of the surface of the sun by analysing the spectrum of the light coming from there. The physics involved is well known, but estimating or measuring the temperature at the centre of the sun requires that we use a fairly well-understood theory of the internal structure of the star. The energy of the sun is produced by thermonuclear reactions. This involves many transformations which lead finally to conversion of hydrogen into helium. The relevant reactions have been worked out in great detail. Many of the steps include emission and absorption of electrons, a crucial step which is necessary that enormous number of neutrinos is produced. We can understand that this will have to be so because large number of protons are effectively converted into neutrons. Just think of the fact that we use four protons to make one Helium nucleus, the basic reaction of nuclear fusion in which enormous amount of energy is released. The conversion of protons into neutrons will involve a beta decay type of reaction which has to involve production of neutrinos. These neutrinos carry enormous amount of the energy produced, but very small fraction of their energy is deposited back into the material of the sun. Indeed the neutrinos leak through the sun with little loss in the upper layers. The number and energy spectrum of the produced neutrinos is not altered greatly while they come out of the sun. The spectrum of the produced neutrinos through various interactions is carefully calculated. It is found that the number and spectrum of neutrinos is very sensitive to the energy distribution of individual particles or, in other words, it is very sensitive function of the temperature at the centre where fusion is intensively active. A result of this is that a measurement of the flux of neutrinos received at the earth can become a sensitive measurement of the temperature at the Centre of the sun! I consider this to be one of the most amazing measurements in whole of astronomy. It almost seems that nature had planned that we should be able to make this astonishing measurement without which the future of astrophysics would have been seriously jeopardized. Neutrinos have to be produced in abundance in thermonuclear reactions at the centre of the sun. Their number would depend sensitively on the temperature of the thermonuclear plasma. And this signal can come out of the interior of the sun because neutrinos have such a low probability of interaction. Readers wanting to ask Prof Yash Pal a question can e-mail him at palyash.pal@gmail.com
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Trends BEIJING: An unmanned Chinese spacecraft returned to Earth successfully on Thursday after more than two weeks in orbit, marking a pivotal moment for the rising power's plans to secure a long-term manned foothold in space. The Shenzhou 8 spacecraft touched down in northern China's Inner Mongolia region after a fiery return to Earth, a live broadcast on Chinese television showed.
Low-level radiation in Europe still a mystery VIENNA: The source of low levels of radioactive iodine-131 detected in several European countries over the past few weeks is still unclear, the UN nuclear agency said. The International Atomic Energy Agency (IAEA) first announced last week that traces had been detected in Europe, after it was tipped off by authorities in the Czech Republic.
— Reuters |
