Something From Nothing: Richard Dawkins & Lawrence Krauss

by frankiespeakin 46 Replies latest watchtower beliefs

• 

  PSacramento

  Depends on your definition of nothing I guess.

  The big bang doesn't state that there was nothing and nothing "exploded", it states that the universe began to expand from a single point and continues to expand to this day.

  Some postulate that a cosmic singularity was there "in the beginning" and that it expanded in an "explosion" of energy and "life".

  No one knows for sure how or what caused it, but we do know that the universe is expanding so, at one point, it must have had a beginning ( of the expansion that is).
• 

  rip van winkle

  Watcher!!! You've been quiet. I wondered where you were and what you were watching. Now, I know.
• 

  james_woods

  One of the really interesting things in the book is that while we talk about the speed of light in terms of universal speed limit and causality, mathematically speaking, it's the speed of ANY massless particle, not just photons.

  Aren't photons the only massless particles we actually have knowledge of? (excluding gravitons until they are discovered)

  I like reading Lawrence Krauss - he is a good author. Two books of his for popular readers are "The physics of Star Trek" and "Beyond the physics of Star Trek". He does nothing there to win fans who are enthusiasts for UFOs or ESP - he is a very practical and straightforward thinker.

  I just hope he is not becoming a "celebrity scientist" like Michio Kaku and Steven Hawking have done. He does at least one of those "science cruise boat tours" each year for Scientific American or Discover.
• 

  EntirelyPossible

  In the beginning there was...nothing.

  And then it exploded.

  That's the point. Science is rapidly discovering that what we once thought of as "nothing" actually has lots of stuff in it, leading to a fundamental discussion of whether or not it's even possible to have a true nothingness.

  Aren't photons the only massless particles we actually have knowledge of? (excluding gravitons until they are discovered)

  Gluons are massless, but they have not yet been observed as free particles. Thus far, they are always confined within a hadron when observed. So, I guess it would be more accurate to say "the speed of a free massless particle" because a photon is certainly not moving at c when it has been absorbed by an electron.

  Thanks for the input, I love it when questions push me to be more accurate!
• 

  james_woods

  Strong force Gluons are massless? That was not my understanding at all...

  I just looked them up in "Q is for Quantum" by John Gribben. It says:

  "The best direct evidence for the existence of gluons comes from the three-jet events first observed in experiments at PETRA collider in Hamburg. In these events, an electron and a positron collide and annihilate one another, producing a quark and an antiquark our of the energy of the two original particles. Almost immediately, either the quark or the antiquark radiates a gluon. Before either of these three particles has gone more than 10-15m, they each turn into a shower of other particles, producing three JETS radiating out from the site of the positron-electron collision.

  The jet of particles produced would (to me) imply a mass.

  Yes, I know - we are off topic (but it is interesting).
• 

  EntirelyPossible

  Strong force Gluons are massless? That was not my understanding at all...

  From everything I have read, there are 8 varieties of gluon, one of which is massless.
• 

  james_woods

  Eight color variations of gluon - yes. I have never heard the notion that one of them is massless...maybe you have a reference?
• 

  EntirelyPossible

  http://adsabs.harvard.edu/abs/1974PThPh..51.1575I

  Massless Vector Gluons in a Unified Gauge Theory of Weak, Electromagnetic and Strong Interactions

  Itoh, C. ; Minamikawa, T. ; Miura, K. ; Watanabe, T. Progress of Theoretical Physics, Vol. 51, No. 5, pp. 1575-1584

  Spontaneously broken SU(2) ×\ U(1) ×\ SU(3)^prime gauge symmetry of weak, electromagnetic and strong interactions is given. All generators of SU(3)^prime commute with those of ordinary SU(3). Fractionally charged twelve quarks are assigned to four triplets of SU(3)^prime. Possible unbroken SU(3)^prime symmetry with massless gluon-like gauge bosons is suggested. Strong interactions are induced by these massless gluons. Leptons are assigned to singlets of SU(3)^prime and so leptons have no strong interactions. Potentials due to massless gluons suggest low lying bound states (usual hadrons) for SU(3)^prime singlet three-quark states and SU(3)^prime singlet quark-antiquark states. One massless gluon cannot be emitted in usual hadron processes. Two or more massless gluon emissions in usual hadron processes are suppressed. When quarks are observed, they should emit massless gluons easily.
• 

  james_woods

  But the strong force is a very short-range force, which implies that the carrier particles would be massive...the massless photon carries the electromagnetic force - which can be of infinite range because the carrier is massless.

  I am going to have to do some more reading on this - I have always understood the color gluons to be massive.

  Of course, there may still be some who think the neutrino is massless - but I thought recent experiments proved a tiny neutrino mass.
• 

  caliber

  The light and sound spectrums had to come together since sound has to travel through a medium (such as Air) and light is an electromagnetic wave

  Light is a transverse wave that can pass through a vacuum (and can have the properties of particles). Sound is a longitudinal wave propagated

  through a medium (gas, liquid, or solid). (a mass of some sort )

  Was not " The Big Bang" both a light and sound feature ?