Dear Cheap Astronomy Ep. 94: Things Can Only Get Bigger

We enlarge upon enlargement. – Why did the Universe inflate? To coin a phrase, in the beginning there was inflation. Within a tiny fraction of the first second, the volume of the universe expanded exponentially, apparently by a factor of 10 to the 78th power – equivalent to something of one nanometer in length expanding to nearly 11 light years in length. This is not to say the early Universe had a radius of 11 light years at the end of inflation. We don’t really know how big the Universe was then, since we don’t really know how big the Universe is now.   – Why does the Universe expand? Here at CA we think is the question that everyone should be asking – that is why, rather than how is the Universe expanding. The question of how the Universe is expanding is generally answered with the waffly concept of dark energy – even though dark energy was brought in fairly recently when it became apparent the Universe’s expansion had been accelerating over time. It was as though everyone had been OK with the idea that the Universe was steadily expanding, but as soon as we knew the expansion was accelerating we needed to conjure up a mysterious force to explain it.   We've added a new way to donate to 365 Days of Astronomy to support editing, hosting, and production costs.  Just visit: https://www.patreon.com/365DaysOfAstronomy and donate as much as you can! Share the podcast with your friends and send the Patreon link to them too!  Every bit helps! Thank you! ------------------------------------ Do go visit http://www.redbubble.com/people/CosmoQuestX/shop for cool Astronomy Cast and CosmoQuest t-shirts, coffee mugs and other awesomeness! http://cosmoquest.org/Donate This show is made possible through your donations.  Thank you! (Haven't donated? It's not too late! Just click!) ------------------------------------ The 365 Days of Astronomy Podcast is produced by the Planetary Science Institute. http://www.psi.edu Visit us on the web at 365DaysOfAstronomy.org or email us at [email protected].