# The Holy Grail of Quantum Physics on Your Kitchen Table [Excerpt]

In this excerpt from his new book, Love and Math, University of California, Berkeley, professor Edward Frenkel uses the Russian soup borscht as a metaphor to explain the duality between electric and magnetic forces

Image: Basic Books/Edward Frenkel

• ### Neutrino Hunters

Editor's Note: Excerpted with permission from “Love and Math: The Heart of Hidden Reality by Edward Frenkel. Available from Basic Books, a member of the Perseus Books Group. Copyright © 2013.

We are all familiar with the electric and magnetic forces. Electric force is what makes electrically charged objects attract or repel each other depending on whether their charges are of the same or opposite signs. For example, an electron has negative electric charge, and a proton has a positive charge (of opposite value). The attractive force between them is what makes the electron spin around the nucleus of the atom. Electric forces create what is called an electric field. We have all seen it in action during a lightning strike, which is caused by the movement of warm wet air through an electric field.

Photo by Shane Lear. NOAA photo library.

Magnetic force has a different origin. It is the force that is created by magnets or by moving electrically charged particles. A magnet has two poles: north and south. When we place two magnets with opposite poles facing each other, they attract, whereas the same poles repel each other. The Earth is a giant magnet, and we take advantage of the magnetic force it exerts when we use a compass. Any magnet creates a magnetic field, as we can see clearly on the picture.

Photo by Dayna Mason.

In the 1860s, British physicist James Clerk Maxwell developed an exquisite mathematical theory of electric and magnetic fields. He described them by a system of differential equations that now carry his name. You might expect these equations to be long and complex, but in fact they are quite simple: there are only four of them, and they look surprisingly symmetrical. It turns out that if we consider the theory in the vacuum (that is, without any matter present), and exchange the electric field and magnetic fields, the system of equations will not change. In other words, the switching of the two fields is a symmetry of the equations. It is called the electromagnetic duality. This means the relationship between the electric and magnetic fields is symmetrical: each of them affects the other in exactly the same way.

Now, Maxwell’s beautiful equations describe classical electromagnetism, in the sense that this theory works well at large distances and low energies. But at small distances and high energies, the behavior of the two fields is described by the quantum theory of electromagnetism. In the quantum theory, these fields are carried by elementary particles, photons, which interact with other particles. This theory goes under the name of quantum field theory.

To avoid confusion, I want to stress that the term “quantum field theory” has two different connotations: in a broad sense, it means the general mathematical language that is used to describe the behavior and interaction of elementary particles; but it may also refer to a particular model of such behavior – for example, quantum electromagnetism is a quantum field theory in this sense. I will mostly use the term in the latter sense.

In any such theory (or model), some particles (like electrons and quarks) are the building blocks of matter, and some (like photons) are the conduits of forces. Each particle has various characteristics: some familiar ones, like mass and electric charge, and some less familiar, like “spin.” A particular quantum field theory is then a recipe to combine them together.

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1. 1. Layer_8 04:28 AM 9/29/13

Worst case if they find magnetic monopoles and they turn out to be bosons.

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2. 2. FB3636 04:41 PM 9/29/13

Electromagnetic waves (photons) propagate because of a ripple effect. A ripple in electric field creates a ripple in magnetic field and vice versa.

A crazy thought:
Maybe gravitational waves propagate in similar way:
A ripple in space creates a ripple in time and vice versa.

I actually come across a recent theory that was based on assuming space and time are exchangeable (just like electric and magnetic fields are).

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3. 3. Percival in reply to FB3636 06:02 AM 9/30/13

To quote Neils Bohr:

"We are all agreed that your theory is crazy. The question that divides us is whether it is crazy enough to have a chance of being correct."

I find that to be an exceedingly interesting crazy idea. Can you provide a cite for more details, please?

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4. 4. FB3636 in reply to Percival 08:49 AM 9/30/13

http://www.technologyreview.com/view/419984/big-bang-abandoned-in-new-model-of-the-universe/

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5. 5. FB3636 12:13 PM 9/30/13

Another one:

What if all kinds of particles propagate using electromagnetic ripple effect; not just photons?

Wouldn't that explain why speed of all kinds of particles limited by speed of light?

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6. 6. Dr. Strangelove in reply to FB3636 02:57 AM 10/1/13

"Maybe gravitational waves propagate in similar way:
A ripple in space creates a ripple in time and vice versa."

Not crazy idea but the standard theory. In general relativity, spacetime is a single entity so gravitational wave propagates in spacetime, not just space or time.

"What if all kinds of particles propagate using electromagnetic ripple effect; not just photons?"

Quantum mechanics is more complicated than that. The wave function of electrons propagate in multi-dimensional phase space. You can't even imagine how they can exist in our four-dimensional universe.

"Wouldn't that explain why speed of all kinds of particles limited by speed of light?"

This is explained by special relativity. Particles with mass cannot move at speed of light because it will require infinite kinetic energy. The speed of light is an asymptote for particle's kinetic energy except for massless particles.

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7. 7. My-higgsbosons 09:09 AM 10/1/13

if it were proven that magnetic monopoles existed , what would they be composed of ?

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8. 8. FB3636 in reply to Dr. Strangelove 01:16 PM 10/1/13

All I know is revolutions in science do not come from conventional thinkers. :-)

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9. 9. verdai 04:48 PM 10/3/13

related from the greatest distance.

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10. 10. dadster 12:43 AM 10/4/13

All this talk about supersymmetry is not crazy enough to have a chance of it being true !

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11. 11. dadster 12:58 AM 10/4/13

Yeah, it's crazier what Dr. Robert Lanza, MD has to say in his seminal work on "BIOCENTRISM " . Time that we seek answers in bio-matter and in life forms than getting obsessed with purely digital logic we seek through non-life material.
There are no objective observation . Material Science has been driven to come to terms with that hard- to- accept concept. Now material scientists are not dealing with physical objects but engaged in the study of objects created by mathematical abstractions ie, objects created in our minds that do not exist in three dimensional physical world palpable to our five physical senses or to our scientific instruments . So, mind is taking precedence over matter. The relationship between mind and matter is what we observe as phenomena the secrets of which cannot be unraveled only from the dimension of physical matter alone . Otherwise ,It would be like studying the projection in two dimensions ,
three dimensional objects and drawing our inferences . It's time, that hardcore mainstream physicists factor in mind into their observations and conclusions and create qualitative maths to express the relationships switching off just purely quantitative approaches only.

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12. 12. edprochak in reply to dadster 09:02 AM 10/9/13

when you come up with an independently measurable unit for MIND, then it can be factored in. until then, I have half a mind that says you can't do it.

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