What is Big Think?  

We are Big Idea Hunters…

We live in a time of information abundance, which far too many of us see as information overload. With the sum total of human knowledge, past and present, at our fingertips, we’re faced with a crisis of attention: which ideas should we engage with, and why? Big Think is an evolving roadmap to the best thinking on the planet — the ideas that can help you think flexibly and act decisively in a multivariate world.

A word about Big Ideas and Themes — The architecture of Big Think

Big ideas are lenses for envisioning the future. Every article and video on bigthink.com and on our learning platforms is based on an emerging “big idea” that is significant, widely relevant, and actionable. We’re sifting the noise for the questions and insights that have the power to change all of our lives, for decades to come. For example, reverse-engineering is a big idea in that the concept is increasingly useful across multiple disciplines, from education to nanotechnology.

Themes are the seven broad umbrellas under which we organize the hundreds of big ideas that populate Big Think. They include New World Order, Earth and Beyond, 21st Century Living, Going Mental, Extreme Biology, Power and Influence, and Inventing the Future.

Big Think Features:

12,000+ Expert Videos

1

Browse videos featuring experts across a wide range of disciplines, from personal health to business leadership to neuroscience.

Watch videos

World Renowned Bloggers

2

Big Think’s contributors offer expert analysis of the big ideas behind the news.

Go to blogs

Big Think Edge

3

Big Think’s Edge learning platform for career mentorship and professional development provides engaging and actionable courses delivered by the people who are shaping our future.

Find out more
Close

The Multiverse: Reviving the Crazy Aunt of Quantum Theory

December 7, 2013, 9:00 AM
137159main_firststars_top_pannel_lg

What is the idea of the multiverse?  It gets back into the issue of what entails a measurement in a quantum mechanical system.  Schrödinger himself actually disliked the idea that the Schrödinger Equation only told you the probability of finding where the electron might be at some point in space and time.  

The equation does work very well for describing, for instance, radioactive isotopes decays.  If I have a radioactive isotope and I say it has a half life of one year, what that means is that after a year, there’s a 50% chance that it decays or a 50% chance that it doesn’t decay.  And if I have a million isotopes after a year, sure enough I’ll have half a million.  However, I don’t know which half will have decayed until the year is up, but I can predict accurately that roughly half of them will go.  

Schrödinger said, "Well what if I had not a million isotopes, but one isotope?  Let’s say it has a half life of an hour.  If it decays, it will emit an alpha particle, that particle will break open a bottle of poisoned gas and the poisoned gas can kill a cat that we put inside a box."  It’s not like we physicists hate cats, but you may argue that the process of observing the radioactive isotope changes whether it decays or doesn’t decay, but few people would say, looking at a cat, that changes whether it’s alive or dead.  So it’s a way of amplifying a microscopic event to something macroscopic.  

You put the cat in the box, you close the lid. After an hour, you open it up.  Quantum mechanics says that there’s a 50% chance that the isotope has decayed in which case it has emitted a particle and the cat has died.  But there is a 50% chance it doesn’t decay in which case we would find a live cat.  Until you open the box, the only way to describe the cat is in an average of half alive and half dead.  This sounds so stupid that we use different language.  

In 1957, Hugh Everett III, in part of his PhD thesis at Princeton proposed an alternative explanation.  He said there was not an average of half alive, half dead.  No collapsing wave functions.  What happened was when we closed up the box initially we split off two parallel universes.  And at the end of the hour, the wave functions don’t collapse. We discover that we live in a universe where the cat lived or the universe where the cat died.  And for every quantum event that has two outcomes, there’s at least that many universes.  So there is in principle an infinite number of parallel universes.  

Needless to say, physicists did not consider this helpful.  And these ideas, which had been later on described by Brice DeWitt as the many worlds interpretation of quantum mechanics had been considered the crazy aunt of quantum theory and ignored up until fairly recently.  But String Theorists and other physicists trying to develop a quantum theory of gravity have found that they needed to dust off the many worlds interpretation and apply it to their theories in order to make them work out.  

In Their Own Words is recorded in Big Think's studio.

Image courtesy of Shutterstock

 

 

The Multiverse: Reviving th...

Newsletter: Share: