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The road to reality by Penrose

  1. Sep 29, 2007 #1


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    I just borrowed this book, and am about to start reading it. However, I am a just a third year undergraduate, and flipping through the book, there looks like there is going to be a lot of new material, and some difficult math. How hard do you think it will be for me to get through it? Is it presented in an understandable way?
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  3. Sep 29, 2007 #2


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    Don't worry about the math. If you want to worry, worry about the foundational physics that he will address. I have "The Emperor's New Mind" and have plowed through parts of that over and over again, and I try to keep up with his lectures on the confluence of GR and quantum theory and how we might craft a convergence by letting go of some features of either model or both. I've got to get the "Road to Reality" but financial strains forbid that for now.

    It is possible that gravitation does not follow the Newtonian model, nor the GR model. We don't know if that is true, and since gravitation is the big player on large scales, there is some question as to whether MOND (which has exhibited some predictive capacity) or other alternative gravitational models may gain some traction. In the Solar system (with the possible exception of the Pioneer probes), classical gravitational models seem to work OK. Once we get to galactic scales, MOND seems to work very well, but it is pretty ad hoc, and cannot cleanly explain the excess binding energy or excess lensing exhibited by clusters of galaxies. The really big questions at the foundations of physics, including the mechanics of gravitation, are up for grabs.
    Last edited: Sep 29, 2007
  4. Oct 1, 2007 #3
    I have been reading this book on and off for at least 6 months now. I was trying to get through the chapters on Calculus on Manifolds (the last I remember:)). I think this book is very different from other books on modern physics that have been written for people not working in physics/maths.

    This book requires understanding of underlying concepts to be of any use. I tried skipping things that I didn't understand but that didn't help since later chapters depend a lot on the initial material.

    Well I am an Electrical Engineer and I have had to go off and read of things I never had in school to understand the material. I remember going back to my Math lectures on complex analysis. I even read some group theory leading to basics of Galois theory. Now I am stuck on differential geometry. Once I am through this I will be able to get to the actual Physics sections of the book:). So I would suggest reading some introductory books on

    1) Complex/Real analysis
    2) Group theory
    3) Differential geometry

    to make sense out of this book. But I must say I have been enjoying this book a lot.
  5. Oct 1, 2007 #4
    I bought this book almost a year ago and find it very amusing and educative. However, I thought that problem in me that I constantly return back in chapters and clarify thing over and over again (should be mentioned that understanding increasing with each turn), but now I see, that I am not the only one!

    At first, I suggest to really concentrate on basics - first chapters, calculus, geometry and, especially, group theory. Later, with this baggage, it will be easier to handle gauge connections, quantum mechanics and other topics. If you do not understand some things then just go to wikipedia or consult other special books on that particular topic...

    If you are not a physicist or matematitian then I suggest to read several popular books on physics to get some general ideas and to get a map for orientation in science.

    Penrose did a very good job. Have fun.
  6. Oct 2, 2007 #5


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    I love the book, honestly. But Penrose sets out to do the impossible: bring the reader from, say, middle school level up to PhD in theoretical physics level in one single book. This is what makes the book on one hand extremely valuable, but also high in information content per word. So you have to read, re-read, and re-read again.
  7. Oct 2, 2007 #6


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    Thanks for the replies everyone... my goal was to finish it by christmas, but I'm starting to think that will be impossible. However, there seems to be so much to gain from finishing it, that I can't not read it!
  8. Mar 9, 2008 #7
    The Road to Reality is a HARD one

    I have been trying to read this book for about two years. I am up to chapter 12. I picked up Visual Complex Analysis by Tristan Needham along the way to help me get to this point. Visual Complex Analysis is a "real" math book, but it was like reading a romance novel compared to The Road. Unless you already are familiar with the matter covered in this book, you would have to be a http://en.wikipedia.org/wiki/Srinivasa_Ramanujan" [Broken] to understand it without other resources, other books, Wikipedia, whatever. A finger pointing at the moon.
    Last edited by a moderator: May 3, 2017
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