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Welcome to Einstein Online - relativity and more! — Einstein Online

Welcome to Einstein Online - relativity and more! — Einstein Online

Practical Physics This website is for teachers of physics in schools and colleges. It is a collection of experiments that demonstrate a wide range of physical concepts and processes. Some of the experiments can be used as starting-points for investigations or for enhancement activities. Many have links to carefully selected further reading and all include information and guidance for technicians. Physics is a practical science. Practical activities are not just motivational and fun: they can also sharpen students’ powers of observation, stimulate questions, and help develop new understanding and vocabulary. Good quality, appropriate physics experiments and investigations are the key to enhanced learning, and clarification and consolidation of theory. We have published a new set of resources to support the teaching of practical science for Key Stages 3-5.

Journal of Cosmology "Invitation" to publish does not guarantee acceptance. All articles are peer reviewed. Approximately 30% of invited articles have been rejected. Approximately 50% of invited articles have been rejected then revised and then resubmitted following peer review, and then accepted. Approximately 20% of invited articles have been accepted without suggested revisions following peer review. Approximately 80% of all articles submitted without invitation, have been rejected. Peer Review The Journal of Cosmology welcomes great ideas. Authors should submit the names, affiliations, and email addresses of 5 scientists qualified to review their paper. All papers are reviewed anonymously by at least two referees who are experts in the field in question. If reviewers suggest publication pending revision, authors will be invited to revise and resubmit the manuscript and to address and respond to criticisms and suggestions by the referees. Papers rejected by both referees cannot be revised and resubmitted. 1).

High School Physics and AP Physics Online Wilkinson Microwave Anisotropy Probe (WMAP) Physics and Astronomy Online Portal The age of the universe Because the first generation of stars formed some time after the big bang, the age of the oldest known stars places a lower limit on the age of the universe. Theory of Stellar Evolution. Stars are remarkably simple systems: they are slowly evolving, nearly spherical clouds composed mostly of hydrogen and helium that can be accurately modeled on a computer. Main-sequence stars are stars, like our Sun, that fuse hydrogen to helium in their cores. The fundamental fuel for a star’s luminosity is mass. Astronomers find it convenient to represent the properties of stars on a Hertzsprung–Russell (HR) diagram, a plot of a star’s luminosity and surface temperature. The HR diagram is a particularly useful way to display the properties of stars in a cluster. Astronomers, however, cannot measure the luminosity of a star directly; they can only measure the flux from a star, F. Should We Believe the Models? The stellar models correctly predict the age and structure of the Sun. Figure 1 Figure 2

Smile Into Your Organs: “A smile is an inexpensive way to improve your looks” Charles Gordy I love the idea that smiling is used as a healing and meditation practice by many ancient cultures. Taoists believe that holding a smile on your face and directing it inwards towards your organs and inner body, is the key to good health and longevity. Traditional Balinese healers know that a smile washes away bad energy and recommend smiling meditation as a simple way to calm the mind and bring health to the soul. Photo by stuck in customs: How to smile on the inside: I was first introduced to the Taoist exercise called the “inner smile” about 15 years ago. Each week we were guided to smile on our face, really feel the smiling energy and then imagine ( in our minds eye ) sending the smiling energy into each of our organs. Now, this might sound super easy, however some weeks – to my surprise – some organs simply refused to receive a smiling breath. Smile into your organs and dissolve negative emotions: .

天文学家:宇宙的起源比大爆炸更早吗? 宇宙的起源比大爆炸更早吗? 记者/刘洪宇 最近,有英国和亚美尼亚科学家表示,他们发现了能够证明宇宙在大爆炸前就已存在的证据——在宇宙微波背景辐射(CMB)中存在“同心圆”,可能证明大爆炸前有事件发生。 仰望星空——宇宙的起源一直是人类关心和探求的终极话题。直到近世,随着科学技术的高速发展,有了科学上的宇宙起源于大爆炸的理论——绝大多数科学家相信宇宙是在大爆炸后产生的,但是对如何发生的爆炸还未有定论,英国天文学家的这一发现为宇宙的起源增加了一个新的注释吗? 低温“同心圆”来自更久远的宇宙? 辽宁日报:近来,英国和亚美尼亚科学家说通过对宇宙微波背景辐射的探测数据的分析,发现了12个同心圆,其中一些有5个圆环,说明一些天体在其历史上发生了5次大规模事件,这是首次发现吗? 张同杰:通过宇宙微波背景辐射的观测发现其存在同心圆的现象,是此类现象的首次发现,也是最新的有别于标准大爆炸宇宙起源的一种观测检验,引起了天文学家尤其是宇宙学家的注意,因为“宇宙从何而来,又会向何处去? 辽宁日报:这个同心圆和圆环是什么? 张同杰:在解释他们发现的同心圆现象之前,首先了解一下宇宙微波背景辐射。 辽宁日报:温度低说明什么? 张同杰:周围的辐射平均温度都是2.73K,也是目前通常看到宇宙微波背景辐射的温度,被认为是137亿年前宇宙大爆炸时留下的,但是数据分析表明存在几个温度更低的环形区域,并且是同心圆形状的。 宇宙可能不止我们所处的这一个 辽宁日报:英国科学家的意思是不是说在目前我们所处宇宙之前还有宇宙存在? 张同杰:是的,对于这种现象的解释,英国天文学家主张一种多宇宙理论或者共形循环宇宙论:不仅在我们所处的这个宇宙之前有宇宙,也可能还有与目前我们所处的宇宙同时存在的其他宇宙,即并行宇宙。 辽宁日报:宇宙之外还有宇宙? 张同杰:如果宇宙之外还有其他宇宙的话,以我们目前的科技水平和观测手段来说是不可能观测到的,因为它距离我们太远了——我们所处的宇宙的视界约137亿光年,而我们目前通过功能最强大的射电望远镜也只能探测到宇宙大爆炸后约30万年的图像,也就是刚才我们一直在讨论的宇宙微波背景辐射。 辽宁日报:那么,对于英国天文学家关于 “辐射同心圆”的这个解释、说法能成立吗? 张同杰:我要强调的是,我们观测不到的,并不等于它不可能存在。 辽宁日报:其他科学家对这种解释是否有不同意见? 张同杰:有的,我手里就有两篇文章。 专家档案DANGAN

Higher Density Blog By now, pretty much all of us know and accept that meditation provides a plethora of benefits, including reduced tension and stress and improved focus and concentration. However, how and why meditation does this has long remained unknown—until now! Harvard University scientists have published the results of an 8-week study that used magnetic resonance imaging (MRI) to examine the effects of meditation on the brain. MRIs were taken at the beginning and end of the 8-week study. We know what you’re thinking: what is this mysterious gray matter that meditation is rebuilding? Research on the brain has shown that the amount and density of gray matter differs from individual to individual, and can determine or signify certain traits or talents. The Harvard study found that meditation can increase the density of the gray matter in the hippocampus, specifically. -The Alternative Daily Found at:

霍金谈宇宙起源:我们从何而来 人类正接近答案 宇宙膨胀有如沸水泡泡 宇宙最可能的历史像是泡泡的表面。许多小泡泡出现,然后再消失 詹姆.哈特尔和我发展宇宙自发创生的图景有一点像泡泡在沸腾的水中形成。 其思想是,宇宙最可能的历史像是泡泡的表面。 通货膨胀的世界纪录应归一战以后的德国。 “上帝的确在掷骰子” 我们是极早期宇宙的量子起伏的产物 早期宇宙中的无规性,意味着在有些区域的密度,比其它地方的稍高。 在过去的百年间,我们在宇宙学中取得了惊人的进步。 虽然广义相对论预言了,宇宙来自于过去一个高曲率的时期,但它不能预言宇宙如何从大爆炸形成。 宇宙最终会再次坍缩吗? 我们正接近回答这古老的问题:我们为何在此? 尽管我们已经取得了一些伟大成功,并非一切都已解决。 霍金旋风在港掀起高潮 工商政界人士趋之若鹜 霍金称人类可圆移民太空梦 周日将抵京作讲座