How do we know the Universe is expanding?
Cosmological redshift was our first clue the universe was expanding. A century ago, Edwin Hubble discovered galaxies outside our own supercluster are all moving away from us. But how do we get from redshift to an expanding universe? That’s the tricky part and most people get it wrong.
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VIDEO ANNOTATIONS/CARDS
Is The Universe Infinite:
https://youtu.be/fApKpDGGDYk
What is the Universe expanding into?
https://youtu.be/0B4tj9c0vG8
How Do We Know Things About Stars?
https://youtu.be/lAu0wenIAIE
What the HECK is Light?!
http://youtu.be/m2-UJAEJzcc
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RELATED YOUTUBE VIDEOS
PBS Space Time on Cosmological Redshift:
https://youtu.be/QXfhGxZFcVE
PBS Space Time on the CMB:
https://youtu.be/3tCMd1ytvWg
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HUGE THANK YOU TO THESE PATRONS
** Andy Kirkham, Nikko Lai, Clint Cloys, Evgeny, Rick Finn, Preston From, Christian McCracken **
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SUPPORT THE SCIENCE ASYLUM
Patreon:
http://www.patreon.com/ScienceAsylum
Advanced Theoretical Physics (eBook):
https://gumroad.com/l/ubSc
Merchandise:
http://shop.spreadshirt.com/scienceasylum/
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OTHER SOURCES
https://arxiv.org/abs/1204.5493
https://arxiv.org/abs/astro-ph/0211011
http://www.astro.ucla.edu/~wright/cosmology_faq.html
Wavelength to RGB:
http://www.wolframalpha.com/widgets/view.jsp?id=23c041a005eec913db5a74171ea72e63
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LINKS TO COMMENTS
Expanding? – seastormsinger:
https://www.youtube.com/watch?v=Vmi_h5A8B2k&lc=z12pzpxwirmiensly23we3wj3nycxxvjq04
Redshift – Yair Eshel Cahansky:
https://www.youtube.com/watch?v=fApKpDGGDYk&lc=z13uhj2r1lb5yxeuu23jh3nx4ubrwdunp
FLOWER Metric – Guest Informant:
https://www.youtube.com/watch?v=fApKpDGGDYk&lc=z12zwpmjcrrbcxspj04cdf0yylucdjnysro0k
List of Topics – aThrasheR:
https://www.youtube.com/watch?v=inPcQeYWVT8&lc=z12iwdxyvruku11hg04chbz5ts2xcxzg0i4
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IMAGE CREDITS
Cosmic Microwave Background:
http://www.esa.int/Our_Activities/Space_Science/Planck/Planck_reveals_an_almost_perfect_Universe
Spectroscope at Lick Observatory:
https://video.kidibot.com/wp-content/uploads/2020/12/youtubomatic/a-3EStar-Spectroscope.jpg
Thumbnail Background:
https://www.nasa.gov/image-feature/goddard/2017/hubble-spots-two-interacting-galaxies-defying-cosmic-convention
