Wheeler Definition and 42 Threads

  1. M

    A MTW Gravitation: Exercise 5.1 | Beginner GR Stress-Energy Tensor Symmetry

    I am a beginner in GR, working my through Gravitation by the above authors. If there is a better place to ask this question, please let me know. I understand (from section 5.7) that the stress-energy tensor is symmetric, and from equation 5.23 (p. 141), it is explicitly symmetric. But...
  2. D

    B Breit Wheeler Matter Production

    Are there any limitations on producing a significant number of electron-positron pairs (say, 10E24 electrons) in one second using the Breit-Wheeler Process or Nonlinear Breit-Wheeler Process? What variables affect this outcome? I suspect it mostly comes down to the pulse repetition rate and...
  3. S

    A Any model or theory in physics akin to "Law without law"?

    When trying to explain from where did all the laws come from, John Wheeler proposed the anaphorism of "Law without law". He proposed that at the "beginning" there were no laws whatsoever, only pure chaos, and that they emerged from randomness and chaos when our universe was created. In his own...
  4. MidgetDwarf

    Relativity Question Regarding Different Editions of Spacetime Physics by Wheeler

    Greetings! I have misplaced my copy of Spacetime Physics by Wheeler (1966 ed/red cover) and wanted to read it again. Was wondering if there is a major difference between the earlier blue hardback?
  5. bob012345

    Understanding Tensors: Is Misner Thorne and Wheeler Enough?

    Summary:: Does the textbook Misner Thorne and Wheeler have all I need to understand tensors in order to learn GR? Does the textbook Misner Thorne and Wheeler have all I need to understand tensors in order to learn GR? I have that textbook but never went through it. Tensors greatly intimidate...
  6. S

    I Wheeler's Pre-geometry model and multiple universes?

    John A Wheeler proposed that the universe emerged from a primordial chaos (some sort of pre-geometry or pre-space) from where all physics emerged in the universe. I thought this could be interesting in the context of multiple universes. Therefore, has any well renowned physicist considered...
  7. S

    I Wheeler's Mutability principle and multiple universes?

    Physicist John A Wheeler proposed the "Principle of mutability" which said that it could be the case that the universe would eventually shrink in a "Big Crunch" and the be re-born in another Big Bang. He proposed that the laws of physics (even the considered most fundamental ones) would change...
  8. Quantum Alchemy

    I Wigner's Friend shows the difference between Observer and Measurement

    You often hear this debate about the role of the observer in Quantum Mechanics. How you view this role is usually dictates the interpretation you prefer. If it's Copenhagen, then the observer is more robust and plays a crucial role in wave function collapse. If it's Many Worlds, then the...
  9. robphy

    Did John Wheeler's Lost FBI File Reveal Secrets of the H-Bomb?

    "The FBI file of John Wheeler" https://physicstoday.scitation.org/do/10.1063/PT.6.4.20191203a/full/ "John Wheeler’s H-bomb blues" https://physicstoday.scitation.org/doi/10.1063/PT.3.4364 "How the Nation’s Hydrogen Bomb Secrets Disappeared"...
  10. S

    A Would Wheeler's oscillatory universe model create different laws?

    According to physicist John Wheeler, the universe is part of a sequence of cycles of Big Bangs and Big Crunches, called cyclic or oscillatory universe model (https://en.m.wikipedia.org/wiki/Multiverse (Mentioned in "Classification schemes") According to this author, in each cycle, the laws of...
  11. S

    I Did Wheeler consider Carter's anthropic multiverse?

    Physicist John Wheeler wrote an article called "Genesis and Observership" where he said near the end: "We have reviewed the evidence out of the big bang tat the universe did come into being and the evidence that not only space but all the structures and laws of physics are mutable. In the...
  12. N

    B "Spacetime Physics" by Taylor and Wheeler

    I've tried to get through this book a couple times in the past but didn't succeed, and am now trying it a third time. I managed to re-read and redo the problems from the first chapter recently, and now I'm on the second one where the authors get into free float frames and the force of gravity...
  13. jedishrfu

    Relativity Wheeler, Thorne and Misner Gravitation Book Revised in 2017

    The classic book on General Relativity by Wheeler, Thorne and Misner is now out: https://www.amazon.com/gp/product/0691177791/?tag=pfamazon01-20 I got to use preprints of the book while doing an independent study of General Relativity in 1973. It brings back fond memories of being tortured by...
  14. J

    Relativity Is Gravitation by Misner, Thorne, Wheeler outdated?

    Hi! With the re-release of the textbook "Gravitation" by Misner, Thorne and Wheeler, I was wondering if it is worth buying and if it's outdated. Upon checking the older version at the library, I found that the explanations and visualization techniques in the sections on differential(Riemannian)...
  15. E

    John Wheeler Biography: A Comprehensive Look

    [mentor's note: moved here from the Quantum Physics forum] Can anybody recommend a good bio of John Wheeler? I'd especially like to read one that tracks his thoughts and theories, rather than one focusing on his personal life. Any suggestions for non-biographical treatment of his work would...
  16. M

    John Wheeler & QM: Unpacking His Interpretation of Quantum Mechanics

    Does anyone know how Wheeler understood QM? Here are some well-known sayings of his (slightly paraphrased): "the wave function does not represent the electron- it represents what we know about the electron; the joint product of all the evidence that is available to those who communicate" "it is...
  17. davidbenari

    Does anyone know what motivated this quote from Wheeler?

    You can talk about people like Buddha, Jesus, Moses, Confucius, but the thing that convinced me that such people existed were the conversations with Bohr. About his time working with Niels Bohr in Copenhagen. http://www.todayinsci.com/W/Wheeler_John/WheelerJohn-Quotations.htm I find this quote...
  18. Z

    An excercise in graviation by misner, thorne and wheeler

    Homework Statement My question is on problem 4.1 of Gravitation. In a generic case of electric field and magnetic field(i.e not $$E=0$$ or $$B=0$$ or $$E$$ and $$B$$ perpendicular), define the direction $$\hat{n}$$ unit vector , $$\hat{n}\tanh...
  19. T

    The book: Spacetime Physics (Taylor - Wheeler) - missing solutions

    Hi I have buyed the book Spacetime physics - Introduction to Special Relativity; Second Edition. It is a great book, although I am currently only at second chapter. There are exercises with solutions in this book. The problem is, there are solutions only to odd numbered exercises. Can I...
  20. R

    About Taylor & Wheeler 3-1 practice problem

    Hi, I'm an amateur italian physics addict, so please sorry for my english, eventually. I'm reading carefully the Taylor & Wheeler 2nd edition, and I'm trying to do all the problems before jumping to the next chapter. Practice problem 3-1, page 78: let's talk about point b. Here we have two...
  21. T

    Exercise 2.5 in Misner, Thorne and Wheeler

    If the squared length of a 4-velocity is -1, how can you have a component v0 =0? I've played with equation (2.35) and produced a result of v = γ(-u2, -u1, -u2, -u3), which doesn't have a squared length of -1. Can anyone help out? TerryW
  22. P

    How to find center of gavity of 2 wheeler

    hi can anyone tell me how to find cg location(height ,position) for two wheeler bike weighing 116 kg....and also the cg of a person(70kg) riding the vehicle and cg of passenger(80kg )sitting at the back......please tell me the procedure in brief to calculate cg of vehicle,rider,passenger...
  23. micromass

    Relativity Gravitation by Misner, Thorne and Wheeler

    Author: Charles W. Misner, Kip S. Thorne, John Archibald Wheeler Title: Gravitation Amazon Link: https://www.amazon.com/dp/0716703440/?tag=pfamazon01-20 Prerequisities: Level:
  24. Greg Bernhardt

    Relativity Spacetime Physics by Edwin F. Taylor and John Archibald Wheeler

    Author: Edwin F. Taylor (Author), John Archibald Wheeler (Author) Title: Spacetime Physics Amazon Link: https://www.amazon.com/dp/0716723271/?tag=pfamazon01-20 Prerequisities: Contents:
  25. E

    Wheeler Feynman absorber theory and non locality

    As per the Wheeler Feynman absorber theory, there cannot be electromagnetic radiation without an emitter and absorber. If we had only a single electron in the universe then disturbing it (accelerating it) would not produce any radiation since there was nothing to absorb it. Hence it would...
  26. R

    Did John Wheeler Really Believe Consciousness Causes Collapse?

    I found this article in 2002 that says Wheeler beleives that counsciousness causes collapse but there is a famous quote in 1983 where he argues counsciusness does not cause collapse. My question is did he change his mind or did the article misinterpret him complelty to sell a "entertaining" sudo...
  27. S

    Are John Wheeler's Unconventional Theories Scientifically Valid?

    He seems very influential but at the same time a lot of his ideas seem inherently unfalsifiable and a bit on the crackpot side (it from bit, PAP, delayed choice, etc). Is this accurate on the whole?
  28. T

    I can't find this reference (Wheeler, N. A.)

    During the D.J. Griffiths, Introduction to Elementary Particles, the author introduces unpublished references "Classical Chromodynamics" and "Bare Bones of the Classical Theory of Gauge Fields", Reed College, Portland, O.R. which is written by Wheeler, N. A. (1981). Where can I find this...
  29. M

    Dismantling 3 Wheeler Gearbox: Idler in Differential Case

    i recently dismantled a 3 speed (tuk tuk) gearbox.But unlike usual 4 wheelers,i found the idler in the differential case.usually for reverse ,idler is also present in the gearbox . When i asked i was told that in 3 wheelers when the reverse gear is applied,the differential as a whole rotates...
  30. N

    Hill wheeler variational equation

    how to solve this equation using mesh point method? and what is the mesh point?
  31. Rasalhague

    Taylor & Wheeler on Thomas rotation

    I have a couple of questions about exercise **103 (yes, a two-star problem!) in Taylor & Wheeler's Spacetime Physics. In part (a), it says "For an atom \beta_r \leq Z/137 (Ex. 101), and for small Z, \beta_r \ll 1. Therefore \tan(d\phi) \approx d\phi \approx -\beta_r^2 \sin(\alpha)." But it's...
  32. pellman

    What are the shortcomings of Misner, Thorne, Wheeler?

    MTW Gravitation is a standard text. For someone learning from this text, what advances since 1973 should he be aware of? Are there any actual corrections: instances of something accepted in 1973 but now known to be wrong?
  33. wolram

    Is a Fiberglass Monocoque Suitable for Building a 50-MPH Electric 3-Wheeler?

    Electric car, it has to have a 50 mile range before recharge, carry two people with room for cargo (shopping), be a home garage project, i have been looking round and think the WarP motor and Zilla controller are a good drive system run on 72 volts. Would a fiber glass monocoque with molded in...
  34. M

    John Wheeler's Legacy: Einstein v. Wheeler's Black Holes

    Einstein v. Wheeler's Black Holes John Wheeler who died earlier this month (13 April) not only coined the term 'black hole', but is of course closely identified with the very concept of a gravitationally collapsed object. So he surely carries much of the blame for the basic deviation...
  35. B

    RIP John Wheeler: Remembering a Great Scientist

    In case anyone has not heard about the sad news that John Wheeler has passed away. http://www.nytimes.com/2008/04/14/science/14wheeler.html?ref=science http://cosmicvariance.com/2008/04/13/goodbye/
  36. Hans de Vries

    John Archibald Wheeler passed away, July 4, 1911, April 13, 2008

    John Archibald Wheeler passed away, July 9, 1911, April 13, 2008 http://cosmicvariance.com/2008/04/13/goodbye/ http://www.nytimes.com/2008/04/14/science/14wheeler.html?_r=2&ex=1365912000&en=ce4e6ed8195a73e5&ei=5090&partner=rssuserland&emc=rss&oref=slogin&oref=slogin...
  37. O

    Solutions manual for Exploring Black Holes by Taylor and Wheeler

    In the Acknowledgements of "Exploring Black Holes" by Taylor and Wheeler they mention that a solutions manual was created by G.P. Sastry and several students. Does anyone know whether it is possible to get a hold of this solutions manual for us self learners. It would be a great help...
  38. P

    Gravitation - Thorne, Misner, Wheeler

    What do you think about this book? What level of mathematics and physics knowledge is needed to understand the material?
  39. fargoth

    Exploring the Feynman-Wheeler Theory

    while looking into huygen's principle i found a site that showed its just another way to look at waves in 1\3\5\...odd dimensions. but i bumped into this: i wanted to know more about this wheeler theory, i tried googling for it, but couldn't find more then 10 lines about it... anyone...
  40. P

    Spacetime Physics by J. Wheeler and E. Taylor

    I have had this book for a while and never really looked into it. It claims to be an easy/nonmathematical approach to relativity. Has anyone read this book before? Can I really understand what the subject matter is covering without any post-calculus math? Is it also a good beginer's guide to...
  41. wolram

    How to Design Suspension Geometry for a Front Wheel Driven Trike?

    A front wheel driven trike to be exact, how would i start designing the suspension geometry, i have in mind an ultra light vehicle driven by the most economical engine "within reason", and street legal, maximum speed 70 mph, to carry two persons with some comfort. the driven wheels would be...
  42. S

    Weinberg vs. Misner, Thorne and Wheeler

    Which book on general relativity is better to start with? "Gravitation" by Misner, Thorne and Wheeler, or "Gravitation and Cosmology" by Weinberg ?
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