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Can the Multiverse Be Tested Scientifically?
astroengine writes: Physicists aren't afraid of thinking big, but what happens when you think too big? This philosophical question overlaps with real physics when hypothesizing what lies beyond the boundary of our observable universe. The problem with trying to apply science to something that may or may not exist beyond our physical realm is that it gets a little foggy as to how we could scientifically test it. A leading hypothesis to come from cosmic inflation theory and advanced theoretical studies — centering around the superstring hypothesis — is that of the "multiverse," an idea that scientists have had a hard time in testing. But now, scientists at the Perimeter Institute for Theoretical Physics, in Ontario, Canada have, for the first time, created a computer model of colliding universes in the multiverse in an attempt to seek out observational evidence of its existence.
String theory is math, not science.
Can the Multiverse Be Tested Scientifically?
You can test specific hypotheses related to how the parts of a multiverse might interact, but no you can't test the general concept of a multiverse since there's nothing inherent to it that requires any detactable phenomena.
There are many multiverse theories and they can all be tested.
Many Worlds: The theory that there are no real "probability waves" in QM, merely overlapping realities that diverge at the time the "waveform" collapses.
This is an easy one. Entangled particles operate using the same physics as wormholes. If one of the entangled pair is accelerated to relativistic velocities, say in a particle accelerator, they will not exist in the same relative timeframe. It would seem to follow that if Many Worlds is correct, one of the particles will be entangled with multiple instances of the other particle, which would imply that every state would be seen at the same time. If the options are left spin and right spin, you'd see an aggregate state of no spin even if no spin isn't a physical possibility. And seeing something that doesn't exist either means you're in a Phineas and Ferb cartoon or Many Worlds is correct.
Foam Universe: This is the sort described in the article.
Yes, impact studies are possible, but they're only meaningful if you have enough data and you can't possibly know if you do. You're better off trying to make a universe, preferably a very small one with a quantum black hole at the throat of the bridge linking this universe to that one. What you will observe is energy apparently vanishing, not existing in any form - mass included, then reappearing as the bridge completely collapses.
Orange Slice Universe: This conjectures that multiple, semi-independent, universes formed out of the same big bang and will eventually converge in a big crunch.
It doesn't matter that this universe would expand forever, left to its own devices, because the total mass is the total mass of all the slices. Although they are semi-independent, they interact at the universe-to-universe level. In this scheme, because there's a single entity (albeit partitioned), leptons cannot have just any of the theoretical states. The state space must also be partitioned. Ergo, if you can't create a state for an electron (for example) that it should be able to take, this type of multiverse must exist.
Membrane-based Universe: This postulates that universes are at an interface between a membrane and something else, such as another membrane.
However, membranes intersecting with the universe are supposed to be how leptons are formed, in this theory. The intersection will be governed by the topology of the membranes involved (including the one the universe resides on), which means that lepton behaviour must vary from locality to locality, since the nature of the intersections cannot vary such as to perfectly mirror variations in the shape of the membrane the universe is on. Therefore, all you need to do is demonstrate a result that is perfectly repeatable anywhere on Earth but not, say, at the edge of the solar system.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
Correct me if I'm wrong, but this would only "prove" the existence of (that variety of) multiverse in a very small subset of universes.
So, let's say I try to poison myself with a pill from a bottle containing 99 cyanide pills and 1 sugar pill. There is a 99% chance I'll die, and a 1% chance I'll live. So in 1% of all universes, I live. I repeat the expriement multiple times, until only 1 in 1 million universes has a surviving me in. That means that in 0.0001% of universes, a very smug version of me is winning a Nobel prize for proving the existence of the multiverse. In 99.9999% of universes, I am dead and nothing has been proven except that I really shouldn't be allowed access to the lab's supply of cyanide pills.
"This is an easy one. Entangled particles operate using the same physics as wormholes. If one of the entangled pair is accelerated to relativistic velocities, say in a particle accelerator, they will not exist in the same relative timeframe. (SNIP)"
That's a misunderstanding of entanglement. There is not per see communication between the particle. When you have an entangled particle there is not one "communicating" the other that it is getting observed. What happens is that *both* particle form a single system with the specific property that when the spin of one particle is measured , the other particle has the anti spin state. Using all sort of relativistic trick on one particle will not do anything whatsoever because there is no communication to the other particle therefor frame of reference do nothing whatsoever.
I dislike the analogy because it does not represent the true nature of QM entanglement , but think of this : you have a red ball and a yellow ball. Put one in a packet at random, keep another one hiddden in a safe on earth. Then send the packet at c speed somewhere. Openning the safe 10 years later will reveal the color of the safe ball and by extent the color of the packet ball no matter how far and that despite not being in the same frame of reference and 10 light years away.
What happens here in entanglement is similar. There is no "teleportation" at c speed of the state of one to the others. Read up on bell's inequality violation.
C. Sagan : A demon haunted world:
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