These conservation laws are special because they are, in some sense, the most fundamental things we know about the universe. We may not know what quarks are made of or how gravity fits with electro-magnetism, but whatever theories we come up with have to conserve energy and momentum (and a few other things like charge)....

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These conservation laws are special because they are, in some sense, the most fundamental things we know about the universe. We may not know what quarks are made of or how gravity fits with electro-magnetism, but whatever theories we come up with have to conserve energy and momentum (and a few other things like charge)....

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To see how important symmetry is to our understanding of the universe, you need to look very closely at what's between my hands. Way, WAY closer than that... Still not close enough... There! The emptiness between the atoms and photons, the substrate everything else rests on... ...space-time itself has certain symmetries. To put it another...

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To see how important symmetry is to our understanding of the universe, you need to look very closely at what's between my hands. Way, WAY closer than that... Still not close enough... There! The emptiness between the atoms and photons, the substrate everything else rests on... ...space-time itself has certain symmetries. To put it another...

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This week on Cartoon Physics, we have Emmy Noether, a mathematician who figured out a lot of important stuff about SYMMETRY (among other things). Hi! Symmetry is one of those physics concepts that everyone has some intuitive understanding of--or at least we all think we do. We can all look at an object and say,...

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This week on Cartoon Physics, we have Emmy Noether, a mathematician who figured out a lot of important stuff about SYMMETRY (among other things). Hi! Symmetry is one of those physics concepts that everyone has some intuitive understanding of--or at least we all think we do. We can all look at an object and say,...

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Why E=mc^2 is cool The Answer Key (Sort of) So if the last two sheets weren’t the full story, why is E=mc^2 so cool? It starts with how Einstein got it. He started with this puzzle: it was was well known that if you push a magnet through a loop of wire, it creates an...

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Why E=mc^2 is cool The Answer Key (Sort of) So if the last two sheets weren’t the full story, why is E=mc^2 so cool? It starts with how Einstein got it. He started with this puzzle: it was was well known that if you push a magnet through a loop of wire, it creates an...

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Why E=mc^2 is Cool Assignment 2: High School Physics E=mc^2 means that Energy (E) equals (=) mass (m) times the speed of light © squared(2). GRADE: CORRECT. That’s what the symbols stand for. As an interesting note, Einstein used “V” for the speed of light in his early papers on E=mc^2. He changed it because,...

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Why E=mc^2 is Cool Assignment 2: High School Physics E=mc^2 means that Energy (E) equals (=) mass (m) times the speed of light © squared(2). GRADE: CORRECT. That’s what the symbols stand for. As an interesting note, Einstein used “V” for the speed of light in his early papers on E=mc^2. He changed it because,...

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