Our excerpt of QUANTUM MAN: Richard Feynman's Life in Science (W. W. Norton, 2011), by Lawrence M. Krauss, has expired. The book is now in paperback and is available from numerous booksellers.

5 Comments

1. 1. radobozov 09:25 AM 3/19/11

   Feynman diagram is way too general description of quantum world although it had its strength for its time.

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2. 2. jack.123 07:02 PM 3/21/11

   I had thought that an explanation of antiparticles going backward in time was forth coming,I guess not.Could someone please explain?

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3. 3. kenkoskinen in reply to jack.123 01:40 AM 3/23/11

   jack.123 no one can explain what any particle that goes backwards in time means. Similarly, no one can really explain what extra spatial dimensions are in superstring theory. However these things have a mathematical sense (I hate to use the term "meaning" since its nonsense to our normal conception). "A particle going backwards in time" only has a mathematically equivalence to an anti-particle. It isn't anything that we can detect/observe.
   
   The case of adding extra spatial dimensions is also a mathematical concept that is inserted into equations so it tames or casts out pesky infinite values. Thereby it eliminates mathematical breakdowns. You cannot do math with infinite values! This doesn't mean extra spatial dimensions do not exist but we have yet to detect one.
   
   The problem of infinite values also relates to the reason Feynman was awarded the Nobel Prize. He was instrumental in "normalizing" quantum electrodynamics (QED). In other words he helped to clean up the mathematics by eliminating them. This is done by guessing at counter-values & inserting them into the equation until one is found to normalize infinite ones. You keep doing it until you wind up with a clean equation. Sometimes normalization works and sometimes it doesn't. In any case, it is the most unscientific activity since this guessing at values have no basis in theory or detections. Nevertheless in the end it worked for QED.
   
   When Feynman was once asked why he got the Noble Prize, he irreverently answered, "For sweeping them under the carpet." Of course the "them" meant the infinite values and "under the carpet" meant they were out-of-sight but not really scientifically solved. Science sometimes proceeds by a pragmatic route. Why the early infinities arose in QED and why they succumbed to the normalization procedure is unknown. However, the end result is QED works smoothly predicting phenomena which is a hallmark of a good theory and is amongst our finest!(See my website: http://antspub.com

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4. 4. jack.123 08:16 PM 3/23/11

   kenkoskinen-So getting rid of the infinities is like adding and subtracting an amount to both sides of an equation.I didn't know that normalization was that easy.So if an antiparticle is traveling backward in time Could it escape a black hole?Is that possible?

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5. 5. debu 12:21 AM 3/25/11

   There is nothing like backward in time. We do not understand entropy in its positive and negative form. Time is a by product of entropy . Durgadas Datta in his balloon inside balloon theory of matter and antimatter universe on opposite entropy path producing FIVE GOD PARTICLES by annihilation at common boundary and injected into our universe as SPACE/DARK ENERGY/ETHER/WIMPS what ever you like to say and our universe is blessed with all laws , gravity which is non uniform as per permeability factor of this cosmic soup causing also expansion of our universe. Mathematics indicate many things which we have to visualise in reality of experiments and cosmic observation and Feynman was the first to help us to explore by saying sweeping under the carpet.

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