Friday, 4 September 2020

3 wonders of the universe, explained | Michelle Thaller | Big Think


3 wonders of the universe, explained Watch the newest video from Big Think: https://bigth.ink/NewVideo Learn skills from the world's top minds at Big Think Edge: https://bigth.ink/Edge ---------------------------------------------------------------------------------- Most people have seen atoms illustrated in textbooks and know about the Big Bang and the speed of light, but there is a good chance what you think you know is not scientifically accurate. Michelle Thaller, an astronomer and Assistant Director for Science Communication at NASA, is here to clear up the misconceptions and explain why atoms don't actually look that way, why the Big Bang is a misnomer, and why the speed of light is more than just really fast. Is there an edge of space? Does light experience time? Watch this video for answers to those and other interesting questions. ---------------------------------------------------------------------------------- MICHELLE THALLER: Dr. Michelle Thaller is an astronomer who studies binary stars and the life cycles of stars. She is Assistant Director of Science Communication at NASA. She went to college at Harvard University, completed a post-doctoral research fellowship at the California Institute of Technology (Caltech) in Pasadena, Calif. then started working for the Jet Propulsion Laboratory's (JPL) Spitzer Space Telescope. After a hugely successful mission, she moved on to NASA's Goddard Space Flight Center (GSFC), in the Washington D.C. area. In her off-hours often puts on about 30lbs of Elizabethan garb and performs intricate Renaissance dances. For more information, visit https://ift.tt/3aB1IjD ---------------------------------------------------------------------------------- TRANSCRIPT: TEXT: This is NOT what an atom really looks like. MICHELLE THALLER: Calling what an electron is and where it is around an atom an ""orbit"" is actually very misleading. In truth electrons don't move around a nucleus the same way that planets move around a star at all. It's very, very different and part of that has to do with what an electron really is. Elementary particles are not tiny, tiny little balls that are actually moving through space. They're more properly described as waves and an electron does not exist in only one location around an atom. It actually exists as a wave. And what that means is that there are volumes around the nucleus of an atom that an electron will fill in. A single electron can actually be an entire sphere around the nucleus of an atom, or these orbitals as we call them, but again I caution you nothing is actually moving around like a planet around a star. Some of these orbitals are shaped like dumbbells and a single electron actually fills out a volume that looks like a dumbbell, or sometimes they look like a disc. So these actually are mathematical solutions which show you where the probability of finding this electron is around an atom. We call these electron shells and it's not that a single electron is moving around inside the shell. It's in the whole shell all at once. The electron actually fills in that volume and all you're looking at is a probability area of where that electron may be. So despite our depictions of atoms with the nucleus in the middle and electrons going around the outside, reality is nothing like that. Electrons form these volumes and some of those volumes even go through the nucleus. Some of these dumbbells actually have electrons existing inside the nucleus as well. What an atom really is, is far more complicated than our artistic depictions of it, far more mysterious and I think really wonderful. One of the best things to study in quantum mechanics is how electrons form these volumes. TEXT: The Big Bang wasn't an explosion. Visualize it like this instead. Now when you hear the term Big Bang that implies an explosion, and we all know how explosions work from our experience. Things actually fly out from a common center. And one of the things is that scientists really don't like describing the Big Bang as an explosion at all. That sort of sets you up in the wrong direction right away because you could imagine that there are galaxies all flying apart away from each other, away from a common center, and flying out into empty space. And the universe we observe is absolutely nothing like that. For example, the whole volume of the universe that we can see with the Hubble space telescope. We can see to a distance of nearly 13 billion lightyears. All of that volume is filled with galaxies. There is no empty center to the universe. And the other thing that we don't observe and we're pretty sure that nobody else ever could either is being on the edge of that. Being on a galaxy right on the edge of expansion and seeing all of the galaxies in one direction because you're looking inside and nothing but... Read the full transcript at https://ift.tt/32Xrmxd

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