Saturday, May 25, 2013

Physics PhD in wrong theory

A theoretical physicist defends what he does:
I study a theory called N=4 super Yang-Mills. ...

First of all, N=4 super Yang-Mills involves supersymmetry. Some forms of supersymmetry are being searched for by the Large Hadron Collider. But those forms involve symmetries that are broken, which allow the particles to have distinctive characters.

In N=4 super Yang-Mills, supersymmetry is unbroken. Every particle has the same mass and the same charge. Furthermore, in N=4 super Yang-Mills that mass is equal to zero; like photons, the particles of N=4 super Yang-Mills would all travel at the speed of light.

There is no group of particles like that in the Standard Model. They can’t be undiscovered particles, either. Particles that travel at the speed of light are part of the everyday world if they have any interaction with normal matter whatsoever, so if the particles existed, we’d know about them. Since they don’t in N=4 super Yang-Mills, we know the theory isn't “true.”

Even with this knowledge, there is an even more certain way to know that N=4 super Yang-Mills isn't “true": it was never supposed to be true in the first place.

A theory by any other name

More than a few of you are probably objecting to my use of the word “theory” in the last few paragraphs. If N=4 super Yang-Mills isn't part of the real world, how could it possibly be a theory? After all, a scientific theory is "a well-substantiated explanation of some aspect of the natural world, based on a body of facts that have been repeatedly confirmed through observation and experiment.”

That's courtesy of the American Association for the Advancement of Science. Confused? You must have been talking to the biologists again. Let’s explain. ...

I’m not a mathematician, however. I’m a physicist. I don’t study things merely because they are mathematically interesting. Given that, why do I (and many others) study theories that aren’t true?

Let me give you an analogy. Remember back in 2008, when Sarah Palin made fun of funding “fruit fly research in France?" Most people I know found that pretty ridiculous.
The AAAS is dominated by leftist-atheist-evolutionists who are sensitive about use of the word "theory" in "theory of evolution". I understand that they are on the warpath against Christians and creationists, but in my experience, scientists frequently use the word theory to describe a collection of ideas that have not been substantiated or confirmed at all.

Fruit fly research is at least telling us truths about fruit flies. One man's research could be proved wrong by another man doing a fruit fly experiment. This guy is bragging that nothing can be done to prove anyone wrong in the field, because the whole field is wrong.

A couple of the comments say that his work is justified because he is a mathematician doing math. But he explicity denies that he is a mathematician, so that is not right.

He also explains:
In referring to the theory I study as “wrong”, I’m attempting to bring readers face to face with a common misconception: the idea that every theory in physics is designed to approximate some part of the real world. For the physicists in the audience, this is the public perception that everything in theoretical physics is phenomenology. If we don’t bring this perception to light and challenge it, then we’re sweeping a substantial amount of theoretical physics under the rug for the sake of a simpler message. And that’s risky, because if people don’t understand what physics really is then they’re likely to balk when they glimpse what they think is “illegitimate” physics.
Silly me, I thought that science was all about trying to approximate the real world. Until I discovered string theorists and others who want nothing to do with the real world.

1 comment:

  1. "Fruit fly research is at least telling us truths about fruit flies. One man's research could be proved wrong by another man doing a fruit fly experiment. This guy is bragging that nothing can be done to prove anyone wrong in the field, because the whole field is wrong."

    The guy did a very good job explaining a very simple concept, and you have missed the whole point of the article. Yes, fruit fly research is teaching us truths about biology. Likewise, N=4 SYM is teaching us a lot about physics. There are several examples in the article and many others that he didn't mention. This theory is not "wrong" in your sense of the word. It doesn't even attempt to provide an exact model of a real physical system.

    "Silly me, I thought that science was all about trying to approximate the real world."

    I think his choice of words here is not the best. The N=4 SYM theory does, in fact, approximate quantum chromodynamics. As a result, it's taught us a lot about nuclear physics.

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