Higgs boson discovery confirmation

Factual Questions
101

Ok, this is going to be a little rremoved from the OP’s question but it’s something that’s been bugging me.

We say that there are a variety of explanations–many worlds, collapsing waves etc–and that it doesn’t matter which one is true if they are mathematically equivalent. At least it doesn’t matter to physicists. But still doesn’t one explanation have to be true? If we take the many worlds explanation seriously, doesn’t that mean that there are many worlds? And either there are many worlds or there aren’t. If a quantum event creates a new world, shouldn’t that new world actually (somehow) exist? Or am I being too naive?

102

That’s not I how read the book. He describes nine fundamentally different types of multiverses. And anywhere from 0 to 9 of these might actually be physically real.

103

The problem is that using “exist” to describe something in a forever inaccessible other universe is depending on everyday words to stretch farther than is allowed. Philosophers have enough problems trying to define “truth,” “reality,” and “existence” in our touchable physical universe. Are mathematical constructs “real”? Does information “exist”? If there are nine distinct types of multiverses is any one more real than any of the others or are they all equal in some sense?

You’re getting into territory that might be described as the singularity of words. They break down at this point and can’t be defined.

104

I mean exists in the same way our world exists. Somewhere there is a world that is identical to our world except in our world a certain electron emitted a photon at time t and in that world it didn’t. Or there isn’t. But there either is or there isn’t.

Math is fine, pure math is fine, but physics has to relate to something. Otherwise it’s not science but rather “making things up,” a very expensive glass bead game.

105

I think you can make distinctions between theories predicting something “real,” but completely outside our realm of being able to test or visualize, vs. theories that are so abstract, they loose any link with what we know and experience.

My understanding of some of Greene’s earlier ideas, as one multiverse idea is 3-dimensional “branes” floating around in some n-dimensional space. That all feels fine and real, even though we’ll never observe it directly.

I’ve never heard any explanation of “Multiple Worlds…” of where the worlds are. Are these newly formed spacial dimension? Some new time axis? what?

106

I have a question too :).

From what I understand, the theory has predicted that if the Higgs exists, it should decay in a certain way, so that type of decay should be more common than would otherwise be expected. But this Higgs decay will be relatively uncommon, so the difference you’d see in “Higgs” and “Non-Higgs” universes is very small. So it’s been necessary to run an enormous number of trials to become confident that this extra bit is really there, and isn’t just some statistical noise.

I guess my question is: what exactly is the event that’s being counted in these trials? Is it literally the exact same experiment run an enormous number of times? If so, is the result of each trial just one of these quantum probabilistic things where occasionally you get a Higgs boson, more commonly you get something else that decays like the Higgs, and sometimes you get something else altogether?

107

I’m having trouble squaring that idea with what’s been stated that many-worlds makes no testable prediction, no new explanatory power, and no new methods for solving wave, or other, equations. So how can the math be “better” in any way?

108

I think I’m confusing The Elegant Universe with this new book. So he’s describing different valid results based on the math? Analogous with -2 and +2 as roots of 4?

109

Also, while I’m just a dumbass on the internet, Lee Smolin is not, and in his book The trouble with Physics he called foundational problems in QM one of the five big unsolved problems in physics, so he at least seems to feel it’s a real problem, not something to be handwaved away with “at least the math works.”

110

Can God make a particle with which He, Himself, cannot collide?

111

It doesn’t :slight_smile:

It fits with what we observe to the same extent that any other interpretation of QM fits with what we observe. When you are faced with multiple explanations of the same phenomena which make the same testable predictions, you have to use Occam’s razor to decide which explanation is worth aligning yourself with. In this case, collapse of the wave function is more similar to invisible dragons, in that it is an unnecessary and overly complicated explanation.

It is not meant to nor does it promise to provide any testable predictions. It is merely an ontology. Not a whole lot of time has been spent on it. It is simply an observation that is “obvious” to some, and “silly” to the sadly misinformed :slight_smile:

It sounds like you agree this is a case of trusting the math, you just don’t like the fact that the math implies something which is unfalsifiable.

There are many potential outcomes in the ordinary vanilla quantum mechanics that everybody agrees is correct. The non-MWI camp would argue that the other outcomes predicted by the Schrodinger equation magically disappear in some ill-understood process corresponding to no known law of physics, under circumstances that are ill-understood, and for which no ontology has ever been found. Many years of human life have been spent trying to understand what this process might be. The MWI camp simply suggests that the other outcomes live-on. We simply do not observe them due to decoherence. To me this provides a far simpler explanation, and a very satisfying ontology. It is also possible that, since this explanation seems so much more reasonable, that it could help provide a foundation for future theories which themselves may very well be falsifiable.

Now, you may think this is all mental masturbation, but most of us (at least those not interested in philosophy) don’t obsess about it. It’s no big deal. It is simply nice to have a satisfying ontology at the back of one’s mind, in the same way that when you aren’t looking up at the sky you assume the moon is still orbiting the earth, even though you cannot prove it without looking at it. Of course, we use Occam’s razor to provide the most useful and agreeable ontology; that even when we aren’t looking, the moon orbits the earth. It’s the same reason most of us are not solipsistic. The MWI is no more mental masturbation that many of the things you take for granted about the world.

112

Relevant

113

Your description is exactly correct!

114

First off, extra points for calling me out my using the euphamism of “sterile intellectualizing” (well, it does sound more polite than “mental masterbation”).

Everything you say makes perfect sense, though I think it’d be better if people clearly labeled a theory like MWI as “philosophy” and not physics to avoid confusion.

The one sticking point is how is MWI less-ugly? Doesn’t that mean it does offer some useful method? Without going into hard-to-explain details, is there any way to convey what you find appealing about the MWI perspective from a “working phycisist” perspective?

115

If there are many worlds, they exist! We wouldn’t say there are many worlds if we didn’t mean it!

116

I don’t know what this means.

117

Yes, I think we’ve arrived at the key sticking point.

MWI doesn’t seem to elegantly explain observed phenomon–where do the additional possibilities live on? Please give us something (e.g., new time dimension), or we can no longer tolerate parasitic string theorists suckling at the teet of the state..:smiley:

118

Thanks!

119

When it comes to the popularizers, they do go overboard in describing things that are more philosophical that physical. However while the MWI is indeed “philosophy of physics”, many would think that it is unfair to draw extra attention to this fact just because it seems bizarre to you. There are many, many bits of ontology that are technically speaking “philosophy” scattered throughout our physics education, and even built into our theories. Most of them you wouldn’t question because they are “obvious” to you, so you are applying a double-standard here. And these bits of philosophy are valuable! It’s very useful to be able to visualize things, and have some underlying picture of reality to fall back on when trying to work out the solution to a problem. As you know from your description of Einstein’s work, a physicist’s intuition about the nature of reality has shown time and time again to be invaluable in moving science forward. An while this intuition is guided by what is technically philosophy, it is in practice very much a part of pragmatic physics. And in moving physics forward, it helps to be able to try to understand “what is really going on.” How else are we to make that “leap” to the next big theory? But when you have mathematics that has many possible interpretations as to “what is really going on” you have to make a mental choice in order to move forward. Typically “beauty” is involved, and of course Occam’s razor. This is, whether you like it or not, a valuable part of practicing physics that is technically philosophy.

To sum up the above paragraph, it is unfair to characterize MWI as philosophy (not that there is anything wrong with philosophy) unless you also characterize the copenhagen interpretation as equally philosophy. If you are going to learn quantum mechanics, it is normal (unless you are an android or are autistic or something) to adopt some mental description of what is actually happening, something that corresponds to the math and is able to give you physical intuition. You have to make some choice. That choice is philosophy, whether you end up on the side of the MWI, copenhagen, or anything else. So it is unfair to pick out the MWI as somehow a special offender. Your real issue with it is that you think it is strange and unnecessarily extravagant. In my opinion this is because you do not understand it well enough.

It offers no useful method. It is less ugly because it makes fewer assumptions. The best I can do is to offer a bit of history and my comment on it.

In the 1920’s it was found that the evolution of particles can be described by a simple differential equation (the Schrodinger equation). This is simple and beautiful. A given particle is described by a wave, which can be many places at once. This wave undulates and evolves according the the Schrodinger equation. But when we make a measurement, we don’t see a wave, we see a ‘blip’. Almost 100 years later today, as far as we can tell, the Schrodinger equation is correct whenever we are not looking. But still, no one knows why or how or what causes the Schrodinger equation to suddenly stop working whenever we make a measurement. Clearly something really crazy is going on! Some complicated physics that causes the wave to “collapse” whenever we try to look at it! But no one has ever figured out any physical interaction that could cause a collapse, because every physical interaction is correctly described by the Schrodinger equation! Except when we are looking! But we are just made up of particles. Our bodies follow the Schrodinger equation too! So there should be no such thing as a special kind of measurement we can make, that would cause a wave function to collapse. How can we cause the wave function to collapse by making a measurement, if we are just made up of particles, and the Schrodinger equation is always correct for particles and doesn’t cause any collapse? Clearly there is a fundamental logical inconsistency in trying to think of the wave function as collapsing. It is a total mess, requires a world-view that is akin to the magical dragons you have mentioned, and some new physical mechanism causing wave function collapse which is ill-defined (what is a measurement?) and self-contradictory. This is why people have tried to use consciousness to explain wave function collapse. This is the ugly mess people get in when they are taught that the wave function actually collapses!

The far simpler explanation is that the Schrodinger equation is always correct. There is no such thing as wave function collapse. There is just the appearance of wave-function collapse due to anthropic self-selection and decoherence. This is a fancy way of saying that there is a large, continuous wave function, and you take that wave function seriously. You don’t postulate “many worlds” so much as you simply assume the wave function exists and evolves according to the Schrodinger equation. The “interpretation” comes in when you notice that the wave function is a sum of many little pieces (like when you integrate a curve you can break it into pieces that you sum up). Because the Schrodinger equation is linear, the evolution of the whole wave function is equivalent to the simultaneous evolution of an infinite number of slightly different “pieces” that make up the wave function. One of those pieces is “you”. Another piece is a slightly different version of “you”. Each version of “you” interacts with pieces of the wave function of the surrounding universe, and becomes entangled with it (interactions mean that conservation laws start forbidding mutually incompatible alternate possibilities). As each version of “you” gets more and more entangled with parts of other waves functions, it becomes impossible for “you v1” to interact with “you v2” because “you v1” has gone and interacted in a way that is logically incompatible with “you v2”. In other words, “you v1” and “you v2” are in “separate universes” practically speaking, although you are both still part of a larger wave function still evolving according to the Schrodinger equation.

It may sound complicated, and it is difficult to explain, and yes, deducing all of this may seem complicated, and some of the deductions may seem bizarre to you, but the underlying idea is very simple and coherent, and not bizarre at all. The universe consists of a wave function that evolves according the Schrodinger equation. Full stop.

120

Multiverse means multiple universes. These are universes separate from our own. They have separate existence. They do not live in our time or space or perhaps even our physics. They are separate. And they all fall out of the math so they are physics. They are not some magic words that physicists dreamed up to be cute. They are as mathematical as the laws of thermodynamics. Where do they live, BTW?

You problem is actually with the philosophy, not with the physics. You’re telling physicists that since you can’t understand the implications of the math in words therefore their math can’t be meaningful. I fully sympathasize with not understanding, but that can’t become the basis for “I’m right, you’re wrong.”

On preview: written before iamnotbatman’s last post.