霍金与黑洞学说【英文】Hawking分析
关于霍金的作文英文
关于霍金的作文英文英文：Stephen Hawking was a brilliant physicist who has made many important contributions to our understanding of the universe. He was known for his groundbreaking work on black holes and the nature of time, as well as his popular science books that made complex concepts accessible to the general public.One of the things that I admire most about Hawking is his perseverance in the face of adversity. He was diagnosed with a rare form of motor neuron disease at the age of 21, which gradually left him paralyzed and unable to speak. Despite these challenges, he continued to work and communicate through the use of a computerized voice synthesizer, and became an inspiration to many people around the world.Another aspect of Hawking's legacy that I findinspiring is his commitment to using science to improve the lives of people everywhere. He was a strong advocate forthe importance of scientific research and education, and believed that science could help us solve some of theworld's most pressing problems.Overall, I believe that Stephen Hawking's life and work serve as a reminder of the power of human curiosity and determination. He showed us that even in the face of seemingly insurmountable obstacles, we can still make important contributions to the world around us.中文：史蒂芬·霍金是一位杰出的物理学家，他为我们对宇宙的理解做出了许多重要贡献。
StephenHawking短文英汉对译
StephenHawking短文英汉对译Stephen Hawking, a world famous British physicist,--- 短文英汉对译Stephen Hawking, a world famous British physicist, will write a children's book with his daughter. Hawking said the book will be "a bit like Harry Potter" but without the magic. "It explains the wonders of the universe(宇宙)," said Hawking, while he was on a visit to Hong Kong last week.Hawking, 64, is probably the world's most famous scientist after Albert Einstein. He is an expert on black holes. He has put his whole life into digging into the beginning (and the end) of the universe."My goal is simple," Hawking once said. "It is to completely understand the universe, why it is as it is and why it is there at all."Hawking has a bad illness that stops him from moving or talking. For a period of time, he had no way to communicate except by blinking(眨眼).Now he sits on a wheelchair with a computer by his side. To communicate, he moves two fingers to control the computer's mouse. He selects his words from the screen, which are then spoken by a voice synthesizer(音响合成器)."I have had the disease for most of my life," Hawking once said. "Yet it has not stopped me from being successful at my work."Although Hawking is such a disabled man, he made great achievements. He has received many awards and prizes for his work over the years. This includes winning the Albert Einstein Award. It is the highest achievement in theoretical physics(理论物理).闻名遐迩的英国物理学家斯蒂芬霍金，将与他女儿一道编写一部孩子们的书籍。
英语作文霍金的故事简介
英语作文霍金的故事简介英文：Stephen Hawking was a renowned physicist and cosmologist who made groundbreaking contributions to our understanding of the universe. He was born in 1942 in Oxford, England, and showed an early interest in science and mathematics. However, at the age of 21, he was diagnosed with amyotrophic lateral sclerosis (ALS), a motor neuron disease that gradually paralyzed him over the years.Despite his physical limitations, Hawking continued his research and became a professor at the University of Cambridge. He is best known for his work on black holes and the theory of relativity, as well as his popular science books such as "A Brief History of Time." His ability to communicate and work despite his severe disability made him an inspiration to people around the world.Hawking's story is a reminder that determination andpassion can overcome even the most daunting obstacles. His famous quote, "However difficult life may seem, there is always something you can do and succeed at," resonates with people facing challenges in their own lives.中文：史蒂芬·霍金是一位著名的物理学家和宇宙学家，他对我们对宇宙的理解做出了开创性的贡献。
霍金与黑洞学说【英文】Hawking
Hawking and Black Holes
Outline: The scientist Information and black holes Hawking radiation Detection of black holes Bets on black holes
The Scientist
equal to the Schwarzschild radius of
the black hole.
• What is inside the event horizon cannot
be known by anyone outside because
even light cannot escape out.
writing, turning a key in a lock Atrophy of hand muscles Atrophy of tongue Difficulty chewing food Difficulty swallowing (dysphagia) Difficulty speaking Muscle cramp
Born 1942 1st class honours from Oxford, after “not
very much work” Symptoms of ALS during Oxford years PhD and Research Fellow in Cambridge Discovered Hawking radiation in 1974 “A Brief History of Time” published in 1987 Numerous honorary degrees and awards Outspoken for world peace, welfare of the
斯蒂芬·霍金英语介绍
斯蒂芬·霍金是以研究是宇宙起源和黑洞闻名于世的。
Stephen Hawking is famous for his research on the origin of the universe and black holes.他做了穿气管手术，因为患有肺炎。
被彻底剥夺了说话的能力，演讲和问答只能通过语音合成器来完成。
霍金的轮椅和语音机器的计算机生成的独特电脑声很容易被世界各地认出来。
He had a tracheotomy because of pneumonia. Being completely deprived of the ability to speak, speech and question-and-answer can only be accomplished through a speech synthesizer. Hawking's wheelchair and voice machine generate unique computer sounds that are easily recognized around the world.我觉得霍金最鼓舞人心的地方是不怕困难的精神。
他患有运动神经元疾病，当时医生曾诊断身患绝症的他只能活两年，I think Hawking's most inspiring place is the spirit of not afraid of difficulties. He suffered from motor neuron disease, when doctors diagnosed him with terminal illness and he could only live for two years.可他一直坚强地活了下来。
成为世界上存活时间最长的病人之一。
2009年，他不再能独立驾驶他的轮椅，他的呼吸越加困难，时常需要使用人工呼吸器，还有几次严重到需要去医院诊疗。
霍金英文例子作文
2019-2020学年浙江省杭州市萧山区高桥初中八年级（上）竞赛数学试卷（12月份）一、选择题（共12小题，每小题3分，满分36分）A ．125的平方根是±15B ．±3都是27的立方根C ．16的算术平方根是4D ．-9是81的一个平方根1．（3分）下列说法不正确的是（ ）A ．3，5，3B ．4，6，8C ．7，24，25D ．6，12，132．（3分）以下列各组数据为边长作三角形，其中能组成直角三角形的是（ ）A ．55°B ．35°C ．25°D ．30°3．（3分）如图，在平行四边形ABCD 中，CE ⊥AB 且E 为垂足．如果∠A =125°，则∠BCE =（ ）A ．155=3B ．116+125=14+15=920C ．(−2)2=22=2D ．(−3)×(−2)=−3×−24．（3分）下列计算正确的是（ ）√√√√√√√√A ．1个B ．2个C ．3个D ．4个5．（3分）观察下列银行标志，从图案看既是轴对称图形又是中心对称图形的有（ ）个．A ．6到7之间B ．7到8之间C ．8到9之间D ．9到10之间6．（3分）估计32×12+20的运算结果应在（ ）√√√A ．A 图B ．B 图C ．C 图D ．D 图7．（3分）在下图右侧的四个三角形中，不能由△ABC 经过旋转或平移得到的是（ ）A ．甲量得窗框两组对边分别相等B ．乙量得窗框的对角线相等C ．丙量得窗框的一组邻边相等D ．丁量得窗框的两组对边分别相等且两条对角线也相等8．（3分）甲、乙、丙、丁四位同学到木工厂参观时，一木工师傅要他们拿尺子帮助检测一个窗框是否是矩形，他们各自做了如下检测：检测后，他们都说窗框是矩形，你认为最有说服力的是（ ）A ．72°B ．108°C ．144°D ．216°9．（3分）如图，该图形围绕自己的旋转中心，按下列角度旋转后，不能与其自身重合的是（ ）A ．32B ．23C ．42D ．3310．（3分）如图，△ABC 是等腰直角三角形，BC 是斜边，将△ABP 绕点A 逆时针旋转后，能与△ACP ′重合，如果AP =3，那么PP ′的长等于（ ）√√√√A ．b ≠0B ．b =0C ．b ≥0D ．b ≤011．（3分）若以a 2−a =b ，则b 的取值范围是（ ）√A ．112.5°B ．120°C ．122.5°D ．135°12．（3分）如图，延长正方形ABCD 的一边BC 至E ，使CE =AC ，连接AE 交CD 于F ，则∠AFC 的度数是（ ）二、填空题（共6小题，每小题4分，满分24分）三、解答题（共6小题，满分60分）13．（4分）化简(−4)2= ．√14．（4分）在平行四边形ABCD 中，若AB =3cm ,BC=4cm ,则平行四边形ABCD 的周长为 cm .15．（4分）如图，在数轴上，A ，B 两点之间表示整数的点有 个．16．（4分）一个多边形的内角和等于它的外角和的5倍，那么此多边形的边数为 ．17．（4分）如图，在梯形ABCD 中，AD ∥BC ，AB =AD ，BC =BD ，∠A =120°．则∠C = 度．18．（4分）已知菱形的两对角线长分别为6cm 和8cm ,则菱形的面积为 cm 2．19．（12分）计算：（1）340−25−2110（2）12+273√√√√√√20．（8分）老师准备测量一段河水的深度，他把一根竹竿插到离岸边1.5m 远的水底，竹竿露出水面的部分刚好0.5m ,把竹竿的顶端拉向岸边，竿顶和岸边的水面刚好相齐，请你帮老师计算河水的深度是多少米？21．（8分）把如图所示的图案，绕点O 依次顺时针旋转90°，180°，270°，你将会得到一个美丽的图案，请作出该图案．22．（10分）如图，在Rt△OAB中，∠OAB=90°，OA=AB=6，将△OAB绕点O沿逆时针方向旋转90°得到△OA1B1．（1）线段OA1的长是，∠AOB1的度数是；（2）连接AA1，求证：四边形OAA1B1是平行四边形；（3）求四边形OAA1B1的面积．23．（10分）如图，在梯形ABCD中，AD∥BC，AB⊥AC，∠B=45°，AD=2，BC=42，求DC的长．√√24．（12分）将平行四边形纸片ABCD按如图方式折叠，使点C与A重合，点D落到D′处，折痕为EF．（1）求证：△ABE≌△AD′F；（2）连接CF，判断四边形AECF是什么特殊四边形？证明你的结论．。
介绍霍金的英文作文
介绍霍金的英文作文英文回答：Stephen Hawking was a renowned theoretical physicist, cosmologist, and author. He was born on January 8, 1942, in Oxford, England. Hawking is best known for his work on black holes and the theory of relativity. His book "A Brief History of Time" became a bestseller and brought complex scientific concepts to a wider audience.Hawking was diagnosed with ALS, a motor neuron disease, at the age of 21. Despite being wheelchair-bound and unable to speak without the use of a voice synthesizer, he continued his groundbreaking work in theoretical physics. His determination and resilience in the face of adversity inspired many people around the world.One of the things that I find most fascinating about Hawking is his ability to communicate complex scientific ideas in a way that is accessible to the general public. Hehad a gift for using analogies and everyday language to explain difficult concepts. For example, he famously described black holes as "the point of no return" and compared the behavior of black holes to the way that cream mixes into coffee.中文回答：史蒂芬·霍金是一位著名的理论物理学家、宇宙学家和作家。
有关霍金英文作文
有关霍金英文作文英文：Stephen Hawking, a world-renowned physicist and cosmologist, is one of the most influential scientists of our time. His contributions to the field of physics have been groundbreaking and have helped to shape our understanding of the universe.One of Hawking's most famous contributions is his work on black holes. He proposed that black holes emit radiation, which is now known as Hawking radiation. This discovery challenged the long-held belief that black holes were completely black and had no emissions.Another important contribution of Hawking's is his work on the origins of the universe. He proposed that the universe began as a singularity, a point of infinitedensity and temperature, and that it expanded rapidly in a phenomenon known as the Big Bang.Hawking's work has also had a significant impact on popular culture. He wrote several books, including "A Brief History of Time," which became a bestseller and helped to make complex scientific concepts accessible to the general public.Overall, Stephen Hawking's contributions to physics and cosmology have been immense and have helped to shape our understanding of the universe.中文：斯蒂芬·霍金，一位世界著名的物理学家和宇宙学家，是我们这个时代最有影响力的科学家之一。
一段英语作文写霍金
一段英语作文写霍金Stephen Hawking, a renowned physicist and cosmologist, was born on January 8, 1942, in Oxford, England. Despite being diagnosed with a rare form of motor neuron disease called amyotrophic lateral sclerosis (ALS) at the age of 21, Hawking's determination and exceptional intellect propelled him to become one of the most influential scientists of our time.Hawking's groundbreaking work on black holes and the theory of relativity has revolutionized our understandingof the universe. His book "A Brief History of Time" became an international bestseller, making complex scientific concepts accessible to the general public.In addition to his scientific achievements, Hawking also made significant contributions to the field of disability rights. Through his own experiences, he raised awareness about the challenges faced by individuals with disabilities and advocated for equal opportunities. He used a computer-based communication system to communicate, which allowedhim to continue his research and share his ideas with the world.Despite his physical limitations, Hawking had an indomitable spirit and an infectious sense of curiosity. He believed that there are no limits to what humans canachieve and emphasized the importance of exploring the unknown. His determination to unlock the mysteries of the universe and his ability to communicate complex scientific concepts to a wide audience have made him an inspiration to countless individuals.霍金，一位著名的物理学家和宇宙学家，于1942年1月8日出生于英国牛津。
霍金的贡献英文作文
霍金的贡献英文作文英文：Stephen Hawking was a renowned physicist and cosmologist who made significant contributions to the field of science. His work on black holes, quantum mechanics, and the origins of the universe revolutionized our understanding of the cosmos.One of Hawking's most significant contributions was his theory of black hole radiation. He proposed that black holes emit radiation, which is now known as Hawking radiation. This discovery challenged the long-held belief that nothing could escape the gravitational pull of a black hole. Hawking's work on black holes also led to a better understanding of the nature of space and time.Hawking also made significant contributions to the study of quantum mechanics. He proposed that the universeis not deterministic, but instead, it is governed byprobabilities. This idea challenged the traditional view of physics, which held that the universe was deterministic and predictable.In addition to his scientific contributions, Hawking was also an advocate for disability rights. He was diagnosed with ALS at the age of 21 and was confined to a wheelchair for most of his life. Despite his physical limitations, he continued to work and inspire others.Overall, Hawking's contributions to science and advocacy for disability rights have left a lasting impact on the world.中文：霍金是一位著名的物理学家和宇宙学家，他对科学领域做出了重大贡献。
描写霍金的英文作文
描写霍金的英文作文英文：Stephen Hawking was a brilliant physicist and cosmologist who made significant contributions to our understanding of the universe. He was born in 1942 in Oxford, England, and was diagnosed with a rare form of motor neuron disease at the age of 21. Despite his physical limitations, he continued to work and pursue his passionfor science.One of his most famous theories is the Hawking radiation, which suggests that black holes emit radiation and eventually evaporate over time. This theory challenged the traditional belief that black holes were completely black and had no way of releasing energy.Hawking was also known for his popular science books, such as "A Brief History of Time," which explained complex scientific concepts in a way that the general public couldunderstand. He believed that science should be accessible to everyone and worked to make it more relatable and interesting.In addition to his scientific achievements, Hawking was also a symbol of perseverance and determination. Despite his physical disabilities, he continued to work and inspire others until his death in 2018.中文：史蒂芬·霍金是一位杰出的物理学家和宇宙学家，对我们对宇宙的理解做出了重要贡献。
我眼中的霍金英文作文
我眼中的霍金英文作文英文：Stephen Hawking is a renowned physicist and cosmologist who has made significant contributions to the field of science. He was diagnosed with a rare motor neuron diseaseat the age of 21, which eventually left him completely paralyzed and unable to speak without the use of a computerized voice system.Despite his physical limitations, Hawking continued to pursue his passion for science and became a leading figurein the study of black holes and the origins of the universe. His work on the theoretical prediction that black holesemit radiation, now known as Hawking radiation, is considered one of his most significant contributions to physics.In addition to his scientific achievements, Hawking was also an inspiration to many for his resilience anddetermination in the face of adversity. He once said, "However difficult life may seem, there is always something you can do and succeed at."中文：霍金是一位著名的物理学家和宇宙学家，他对科学领域做出了重要的贡献。
关于霍金英文作文80词
关于霍金英文作文80词English: Stephen Hawking, a brilliant theoretical physicist, captured the imagination of the world with his groundbreaking work on black holes and the nature of the universe. Diagnosed with a rare motor neuron disease at the age of 21, he defied the odds and continued to make significant contributions to the field of cosmology. His book, "A Brief History of Time", brought complex scientific concepts to a wider audience and solidified his status as a scientific celebrity. Hawking's determination, humor, and resilience in the face of his physical limitations inspired millions around the world and left a lasting legacy in the world of science.Translated content: 史蒂芬·霍金是一位才华横溢的理论物理学家，他凭借其对黑洞和宇宙本质的突破性工作吸引了全世界的想象力。
在21岁被诊断出患有一种罕见的运动神经疾病后，他挑战了种种困难，并继续为宇宙学领域做出重大贡献。
他的著作《时间简史》将复杂的科学概念传播给更广泛的读者群，巩固了他作为科学名人的地位。
霍金英文初中作文
霍金英文初中作文英文：Stephen Hawking is one of the most famous scientists in the world. He was a theoretical physicist and cosmologist who made groundbreaking contributions to our understanding of the universe. Despite being diagnosed with a motor neuron disease at the age of 21, he continued to work and inspire others until his death in 2018.Hawking's work focused on the study of black holes and the origins of the universe. He proposed the idea that black holes emit radiation, which is now known as Hawking radiation. He also worked on the theory of the Big Bang, which explains how the universe began.In addition to his scientific contributions, Hawking was known for his popular science books and his ability to explain complex concepts in a way that was accessible to everyone. He was also a strong advocate for disabilityrights and spoke out about the importance of funding for scientific research.I think that Hawking's legacy will continue to inspire future generations of scientists and thinkers. His work has helped us to better understand the universe and our placein it. He also showed us that even in the face of adversity, we can still achieve great things.中文：史蒂芬·霍金是世界上最著名的科学家之一。
霍金一生英文作文
霍金一生英文作文英文：Stephen Hawking is a legendary figure in the field of science. He was a brilliant physicist and cosmologist who made significant contributions to our understanding of the universe. Despite being diagnosed with a rare form of motor neuron disease at the age of 21, he went on to achieve great success in his career.Hawking's work on black holes and the Big Bang theory has had a profound impact on the scientific community. He was the first to propose that black holes emit radiation, which is now known as Hawking radiation. He also developed a theory of cosmology that combined general relativity and quantum mechanics, known as the Hawking-Hartle state.In addition to his scientific achievements, Hawking was known for his resilience and determination. Despite being confined to a wheelchair and unable to speak, he continuedto work and communicate with the world through a computerized voice system. He also had a great sense of humor and was known for his witty remarks.One of my favorite quotes from Hawking is, "Intelligence is the ability to adapt to change." This quote resonates with me because it reminds me that in order to succeed in life, we must be able to adapt to the challenges that come our way. Hawking's own life is a testament to this, as he faced many obstacles but never gave up on his pursuit of knowledge.中文：史蒂芬·霍金是科学领域的传奇人物。
原创英语阅读理解霍金 Hawking
The world has lost one of its brightest stars. British physicist Stephen Hawking died on March 14, at the age of 76.Hawking was known for his vast knowledge of black holes and the Big Bang theory, which attempts to explain how the universe began. His 1988 book A Brief History of Time, which contains his understanding of the universe, is one of the biggest-selling science books of all time.His hard work led him to receive many awards and prizes. Forexample, in 2006, he was awarded the Copley Medal, anoutstanding award for scientific achievement.But his fame didn’t only come f rom his scientific achievements—his life experience was also inspiring. At the age of 21, he was diagnosed with motor neurone disease (运动神经元病), before being confined to a wheelchair and needing the help of a voice synthesizer (合成器) to speak. He was predicted to die within a few years, yet he lived on to become one of the greatest scientists the world has ever known.Although he’s no longer with us, his legacy will surely live on. As Sajid Javid, a UK government minister, put it, “A brie f history on Earth; an eternity in the stars.”【语篇概述】本文是一篇时文报道。
霍金英语介绍带翻译
霍金以其在理论物理和宇宙学方面的研究而闻名。他建立了一种由广义相对论和量子力学联合解释的宇宙学理论。他还发现黑洞会发射辐射，这种辐射后来被称为霍金辐射，这是物理学界一个重大的突破性发现。
In addition to his scientific work, Hawking also made significant contributions to popularizing science. He appeared in numerous television shows and documentaries, and wrote several popular science books aimed at a general audience. Hawking's ability to explain complex scientific theories in a way that was accessible to the public has made him a household name around the world.
除了他的科学研究工作外，霍金还对科学的普及做出了重大贡献。他出现在许多电视节目和纪录片中，并撰写了几本面向普通读者的科普书籍。霍金能够以通俗易懂的方式解释复杂的科学理论，使他成为了全球家喻户晓的名字。
Stephen Hawking passed away on March 14, 2018, at the age of 76, leaving behind a legacy of scientific discovery and popularization. His work has had a lasting impact on the field of physics and has inspired countless young scientists to pursue a career in the sciences.
霍金学无止境英文作文
霍金学无止境英文作文English: Stephen Hawking's study of the universe seems to have no end. Throughout his career, he made significant contributions to our understanding of black holes, the Big Bang theory, and the nature of space and time. His groundbreaking work on the theory of everything and his popular science books brought complex scientific concepts to a wider audience. Despite his physical limitations due to ALS, he continued to inspire people with his determination and remarkable mind until his passing in 2018. Hawking's legacy lives on through his research, teachings, and the impact he has had on the scientific community and beyond.中文翻译: 斯蒂芬·霍金对宇宙的研究似乎没有尽头。
在他的整个职业生涯中，他对我们对黑洞、宇宙大爆炸理论和时空本质的理解做出了重要贡献。
他关于万物理论的开创性工作和他的科普书籍将复杂的科学概念带给了更广泛的读者。
尽管受到肌萎缩侧索硬化症的身体限制，他仍然以他的决心和卓越的头脑鼓舞着人们，直至他在2018年离世为止。
霍金的遗产通过他的研究、教导以及他对科学界及其他领域的影响而延续。
霍金英语作文,六年级四十字
霍金的精神启示In the vast universe, there was a man whose spirit shone brighter than any star. His name was Stephen Hawking, a British theoretical physicist and cosmologist, renowned for his groundbreaking work in the field of black holes and relativity. Despite being confined to a wheelchair for most of his life, Hawking's mind was free to explore the mysteries of the universe, making him a true hero of science.Hawking's journey was not an easy one. Diagnosed with Amyotrophic Lateral Sclerosis (ALS) at the age of 21, he was told that he had only a few years to live. But instead of succumbing to despair, Hawking chose to fight back. With the help of a voice synthesizer, he continued his research, sharing his insights and theories with the world. His courage and perseverance were an inspiration to many, showing that no matter what obstacles life throws at us, we can still achieve greatness if we have the will and determination.Hawking's legacy is not just in his scientific contributions but also in his unwavering spirit. He taughtus that life is not about how many breaths you take, but about the moments that take your breath away. Despite his physical limitations, Hawking lived each day to the fullest, making the most of every moment. His life was a testamentto the power of the human spirit, showing us that we can overcome any obstacle if we have the will and the courage.In conclusion, Stephen Hawking's life was a remarkable journey of courage, perseverance, and scientific discovery. His spirit continues to inspire us to pursue our dreams and aspirations, reminding us that the true measure of aperson's worth is not their physical abilities but their spirit and determination. Hawking's legacy will forever bea beacon of hope for those facing challenges and obstaclesin their own lives.**霍金的精神启示**在浩瀚的宇宙中，有一位名叫斯蒂芬·霍金的人，他的精神比任何星星都要闪耀。
写霍金的英文作文100
写霍金的英文作文100英文：Stephen Hawking, a brilliant physicist and cosmologist, is a name that is synonymous with intelligence, perseverance, and determination. He was diagnosed with ALS at the age of 21, which left him paralyzed and unable to speak, but he did not let that stop him from pursuing his passion for science.As a scientist, he made groundbreaking discoveries in the field of black holes and the origins of the universe. His book, A Brief History of Time, became an international bestseller and brought complex scientific concepts to the general public. He also made appearances on popular TV shows, such as The Simpsons and The Big Bang Theory, and became a pop culture icon.Despite his physical limitations, Hawking continued to work and inspire people until his death in 2018. He oncesaid, "Remember to look up at the stars and not down atyour feet. Try to make sense of what you see and wonder about what makes the universe exist. Be curious."中文：霍金，一个才华横溢的物理学家和宇宙学家，是智慧、毅力和决心的代名词。
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Dissecting a Black Hole
• A non-rotating black hole is particularly event horizon simple. • There is a point at the center called the singularity (奇點). It has zero size and infinite density. In fact, its properties cannot be described by currently known physics. • The event horizon (穹界) is a sphere centered at the singularity with radius equal to the Schwarzschild radius of the black hole. • What is inside the event horizon cannot be known by anyone outside because even light cannot escape oand Singularity
8
No-hair Theorem
Hair here means something complicated (e.g. different styles, colors, perms, etc…). Black holes have no hair because they are simple. Only three things completely characterize a black hole (Hawking 1972): – mass – angular momentum – electric charge
3 June 2006
Hawking and Black Holes
Outline: The scientist Information and black holes Hawking radiation Detection of black holes Bets on black holes
The Scientist
Amyotrophic Lateral Sclerosis
肌萎縮性脊髓側索硬化症 Also called Lou Gehrig’s disease Symptoms: Difficulty standing, walking, or running
Clumsiness – Frequent tripping or falls Difficulty with fine hand motions such as
5
The Black Hole Radius
2GM rs 2 c
For any mass, there is a smallest radius beyond which the object becomes a black hole. This smallest radius rs is called the Schwarzschild radius. Hawking: This defines the size of a black hole, and it depends on the mass only. Anything smaller than its corresponding Schwarzschild radius becomes a black hole.
Black Hole
Black holes represent the final victory of gravity. A black hole is black because gravity is so strong that light cannot escape. The escape velocity at a distance r from the center of an object with mass M is
4
Space Warps
If
we imagine the spacetime as a “rubber sheet”, then any mass would produce warpings in it. Since black holes produce very strong gravity, spacetime is significantly warped (curved) around them. We see strong light-bending and gravitational redshift.
Born
1942 1st class honours from Oxford, after “not very much work” Symptoms of ALS during Oxford years PhD and Research Fellow in Cambridge Discovered Hawking radiation in 1974 “A Brief History of Time” published in 1987 Numerous honorary degrees and awards Outspoken for world peace, welfare of the handicapped, and other current issues
buttoning,
writing, turning a key in a lock Atrophy of hand muscles Atrophy of tongue Difficulty chewing food Difficulty swallowing (dysphagia) Difficulty speaking Muscle cramp
v escape
2GM r
Light rays
The escape velocity increases with mass and decreases with radius. If vescape> c, then light cannot escape and we have a black hole.