The MultiVerse Simply Explained - Part 5 of 5 (Or How To Bake Your Noodle In A Few Easy Steps)

This is the last in a five part series on Multiverses. I hope that you enjoyed it.

The Multiverse is an hypothesis that there are more universes than the one that we can currently observe with our eyes and various scientific instruments.

In previous parts, I explained the various types of multiverses that are being proposed. There are actually more multiverse ideas than I have talked about but I am not going to get into those because they are more mathematical, more abstract and less interesting in a visceral way.

In this last part I will present the evidence for the Multiverse (short answer: there ain't much)

_{(Image Credit: My dismal MSPaint skills - feel free to mock them in the comments :)}

The Conventional Multiverse

This one which is explained in Part 1 does not have any evidence for it ... yet. As we peer to the edges of the observable universe we also go back into time until we hit the Cosmic Microwave Background. This is the curtain that we cannot peer beyond. It is that point in time when matter cooled enough to re-combined from ions into neutral atoms and allowed the Universe to become safe for photons to travel. So no luck there.

Maybe as the Universe ages further reaches of the Universe will become available to our instruments or we may develop better detectors beyond what we can currently do. This is basically a not-in-our-lifetimes proposition.

_{The Cosmic Microwave Background Providing Clues About the Temperature Distribution of The Universe
(Image Credit: Wikimedia Commons)}

The Bubble Multiverse

It is proposed that if there are many universes that are bubbles separated from one another then they might interfere with each other. This could manifest by injecting energy into the affected regions of our universe and raise the local temperature.

In 2010 an analysis of the WMAP data (Wilkinson Microwave Anisotropy Probe) appeared to find evidence of abnormal warming in one region of the sky suggesting that our universe collided with any other parallel universe in the distant past. Unfortunately, a follow-up investigation of the data from WMAP along with that from the Planck satellite which has a higher resolution did not find any statistically significant evidence for this. As well, other analyses are not finding evidence of any gravitational pull of other universes on ours (i.e. there is no large scale matter flow).

_{(Image Credit:The Blue Diamond Gallery}

Many Worlds Multiverse

This hypothesis apparently ties in well with some string theories in physics and it resolves the weird mysticism of quantum mechanics but alas it seems to have no evidence whatsoever for its existence.

The Holographic Multiverse

Fermilab physicist Craig Hogan proposed that the holographic universe implies that there should be quantum fluctuations in spatial position and that would lead to a background noise that would be measurable by gravitational wave detectors. Analyses of measurements of gamma ray burst GRB 041219A shows that this noise is absent down to a very small scale so it looks like this one may be a no-go as well.

The Simulated Multiverse

If this one were true there would literally be no way to test it as the computer program simulating us would likely disallow such activities. As a physical theory this one is truly un-testable.

Closing Words

The Multiverse ideas are entertaining for a good read over a coffee and a snack. They ultimately may be un-testable which many think makes for a poor scientific hypothesis.

At the very least these ideas have provided good material for many sci-fi novels, TV shows, movies and cartoons.

_{(Image discovered using the 'labelled for re-use' search parameter, the bubble text has been modified.)}

Further Reading

Part 1: The Conventional Multiverse
Part 2: The Bubble Multiverse
Part 3: The Many-Worlds Multiverse
Part 4: The Holographic Universe and the Simulated Universe

Amazon Link (not an affiliate link, I get nothing from this): "The Multiverse: The Theories of the Multiple Universe", ed. Paul F. Kisak, CreateSpace Independent Publishing Platform, December 2015.