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zett24 favorited a video
(4 months ago)
Imagine two observers, one seated in the center of a speeding train car, and another standing on the platform as the train races by. As the center ...
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Imagine two observers, one seated in the center of a speeding train car, and another standing on the platform as the train races by. As the center of the car passes the observer on the platform, he sees two bolts of lightning strike the car - one on the front, and one on the rear. The flashes of light from each strike reach him at the same time, so he concludes that the bolts were simultaneous, since he knows that the light from both strikes traveled the same distance at the same speed, the speed of light. He also predicts that his friend on the train will notice the front strike before the rear strike, because from her perspective on the platform the train is moving to meet the flash from the front, and moving away from the flash from the rear.
But what does the passenger see? As her friend on the platform predicted, the passenger does notice the flash from the front before the flash from the rear. But her conclusion is very different. As Einstein showed, the speed of the flashes as measured in the reference frame of the train must also be the speed of light. So, because each light pulse travels the same distance from each end of the train to the passenger, and because both pulses must move at the same speed, he can only conclude one thing: if he sees the front strike first, it actually happened first.
Whose interpretation is correct - the observer on the platform, who claims that the strikes happened simultaneously, or the observer on the train, who claims that the front strike happened before the rear strike? Einstein tells us that both are correct, within their own frame of reference. This is a fundamental result of special relativity: From different reference frames, there can never be agreement on the simultaneity of events.
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zett24 favorited a video
(4 months ago)
Od dobrych kilkudziesięciu lat fizycy kontynuują ostatnie i niedokończone dzieło Alberta Einsteina poszukując Świętego Graala nauki, teorii ostatec...
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Od dobrych kilkudziesięciu lat fizycy kontynuują ostatnie i niedokończone dzieło Alberta Einsteina poszukując Świętego Graala nauki, teorii ostatecznie unifikującej wszystkie znane prawa natury i opisującej cały Wszechświat jednym koherentnym zbiorem równań. Droga, którą kroczą, nie należy do najprostszych. W przeszłości wiodła przez szczególną i ogólną teorię względności, przez mechanikę kwantową, przez zunifikowaną teorię pola, przez jedenaście wymiarów, przez supersymetrię i supergrawitację. Obecnie naukowcy znajdują się na pierwszym z końcowych - tak im się przynajmniej wydaje - etapów. Przypuszczają, że intensywnie badana teoria superstrun stanowi podwaliny ostatecznego rozwiązania, które zostanie osiągnięte w niedalekiej przyszłości
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zett24 favorited a video
(4 months ago)
Carnegie Mellon Professor Randy Pausch (Oct. 23, 1960 - July 25, 2008) gave his last lecture at the university Sept. 18, 2007, before a packed McCo...
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Carnegie Mellon Professor Randy Pausch (Oct. 23, 1960 - July 25, 2008) gave his last lecture at the university Sept. 18, 2007, before a packed McConomy Auditorium. In his moving presentation, "Really Achieving Your Childhood Dreams," Pausch talked about his lessons learned and gave advice to students on how to achieve their own career and personal goals. For more, visit: http://www.cmu.edu/randyslecture. Also learn about the Randy Pausch Memorial Bridge: http://www.cmu.edu/randyslecture/brid...
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bbking808 cleveland ohio
14/88
Do u know where I can download the album "De la Soul is Dead "?
I love this album but i just cant find it