Dunking on the Big Bang? Bouncing Cosmology Rebounds🏀
21.1 هزار بار بازدید -
3 سال پیش
-
You probably think all cosmologists
You probably think all cosmologists believe in the Big Bang. After all, there was a TV show named after it! But some cosmologists doubt the Big Bang really happened. Is it the correct description of the origin of our observable universe? Several pernicious problems plague this otherwise 'perfect theory', most prominently the seemingly unavoidable singularity at "time zero" inherent in most versions of the theory. Could a 'bouncing model' explain all the features of our cosmos; preserving the Big Bang's successes, but avoid the problem of the singularity?
This video explores an intriguing new model by Anna Ijjas and Paul Steinhardt wherein the universe evolves from a previous cycle, through a bounce to our present expanding universe, without recourse to singularities, inflation, the multiverse or other 'pesky' features of the Big Bang.
The authors illustrate how cosmological models with a classical (non-quantum gravitational, non-singular) bounce generically resolve fundamental problems in cosmology. These include the well-known horizon, flatness, and inhomogeneity problems; the small tensor-to-scalar ratio observed in the cosmic microwave background; the low entropy at the beginning of a hot, expanding phase; and the avoidance of quantum runaway. The same diagrammatic approach can be used to compare with other cosmological scenarios. The most tantalizing aspect of this new model is, to many cosmologists, its falsifiability -- the ability to be proven WRONG, not right, via CMB polarization experiments like the Simons Observatory.
So the question becomes: "Bang or Bounce?" Which do you think is more plausible?
00:00 Solutons often create problems
01:00 Big Bang
02:00 The singularity problem
03:50 Inflation
07:00 Bouncing Basics
12:00 No need for quantum gravity
19:00 Smoothness challenges
20:00 Another Scalar field to the rescue
25:00 future Cosmic Microwave Background probes
Credits:
"Bouncing Cosmology Made Simple" by Anna Ijjas and Paul Steinhardt (2018) https://arxiv.org/abs/1803.01961
CMB Images courtesy of NASA https://www.nasa.gov/feature/making-s...
Simons Observatory simonsobservatory
My TEDx talk: Going to the ends of the Earth to dis...
More info: Patrick Peter www.cpt.univ-mrs.fr/~cosmo/SW_2017/PPT/Peter.pdf
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~-~~-~~~-~~-~
Please watch: "Neil DeGrasse Tyson: Plays the Race Card!"
Neil DeGrasse Tyson Hit Me With the R...
~-~~-~~~-~~-~
This video explores an intriguing new model by Anna Ijjas and Paul Steinhardt wherein the universe evolves from a previous cycle, through a bounce to our present expanding universe, without recourse to singularities, inflation, the multiverse or other 'pesky' features of the Big Bang.
The authors illustrate how cosmological models with a classical (non-quantum gravitational, non-singular) bounce generically resolve fundamental problems in cosmology. These include the well-known horizon, flatness, and inhomogeneity problems; the small tensor-to-scalar ratio observed in the cosmic microwave background; the low entropy at the beginning of a hot, expanding phase; and the avoidance of quantum runaway. The same diagrammatic approach can be used to compare with other cosmological scenarios. The most tantalizing aspect of this new model is, to many cosmologists, its falsifiability -- the ability to be proven WRONG, not right, via CMB polarization experiments like the Simons Observatory.
So the question becomes: "Bang or Bounce?" Which do you think is more plausible?
00:00 Solutons often create problems
01:00 Big Bang
02:00 The singularity problem
03:50 Inflation
07:00 Bouncing Basics
12:00 No need for quantum gravity
19:00 Smoothness challenges
20:00 Another Scalar field to the rescue
25:00 future Cosmic Microwave Background probes
Credits:
"Bouncing Cosmology Made Simple" by Anna Ijjas and Paul Steinhardt (2018) https://arxiv.org/abs/1803.01961
CMB Images courtesy of NASA https://www.nasa.gov/feature/making-s...
Simons Observatory simonsobservatory
My TEDx talk: Going to the ends of the Earth to dis...
More info: Patrick Peter www.cpt.univ-mrs.fr/~cosmo/SW_2017/PPT/Peter.pdf
Join this channel to get access to perks:
@drbriankeating
Support the podcast: Patreon: drbriankeating
And please join my mailing list to get resources and enter giveaways to win a FREE copy of my book (and more) http://briankeating.com/mailing_list.php 📝
🎥 🎥 Watch my most popular videos🎥 🎥
Frank Wilczek Nobel Prizewinner Frank Wilczek: Beau...
Weinstein and Wolfram Stephen Wolfram vs. Eric Weinstein: M...
Sheldon Glashow: Sheldon Glashow: The Power of Useless...
Michael Saylor The Physics of Bitcoin Michael Saylor: The Physics of Bitcoi...
Sir Roger Penrose, Nobel Prize winner: Nobel Prize in Physics, Black Holes a...
Jill Tarter Jill Tarter: Time to Stop SETI?
Sara Seager Venus LIfe: Did Scientists Discover Life on Venus...
Noam Chomsky: Noam Chomsky: Consciousness, Elon Mus...
Sabine Hossenfelder: Sabine Hossenfelder: That New Theory ...
Sarah Scoles: Sarah Scoles, Author of “They Are Alr...
Stephen Wolfram: Has Stephen Wolfram discovered a new ...
🏄♂️ Find me on Twitter at Twitter: DrBrianKeating
🔥 Find me on Instagram at Instagram: DrBrianKeating
📖 Buy my book LOSING THE NOBEL PRIZE: http://amzn.to/2sa5UpA
🔔 Subscribe for more great content https://www.youtube.com/DrBrianKeatin...
✍️Detailed Blog posts here: https://briankeating.com/blog.php
📧Join my mailing list: http://briankeating.com/mailing_list.php
👪Join my Facebook Group: Facebook: losingthenobelprize
🎙️Please subscribe, rate, and review the INTO THE IMPOSSIBLE Podcast on iTunes: https://itunes.apple.com/us/podcast/i...
🎙️Listen on all other platforms: https://wavve.link/into
A production of http://imagination.ucsd.edu/
Support the podcast: Patreon: drbriankeating
Please watch: "Neil DeGrasse Tyson: Plays the Race Card!"
Neil DeGrasse Tyson Hit Me With the R...
3 سال پیش
در تاریخ 1400/05/07 منتشر شده
است.
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