Sunday, 17 April 2011

BBC - Everything and Nothing - Jim Al-Khalili

BBC - Everything and Nothing - Nothing

From BBC: 'Two-part documentary which deals with two of the deepest questions there are - what is everything, and what is nothing?

In two epic, surreal and mind-expanding films, Professor Jim Al-Khalili searches for an answer to these questions as he explores the true size and shape of the universe and delves into the amazing science behind apparent nothingness.



  • if our sun was a grain of sand, there are more stars in the universe, than all the grains of sand, on all the beeches on our world 1'
  • if static infinite universe all night sky would be bright (olbers paradox)10'
  • nebullae are other galaxies 17'
    • stellar parallax
    • Hubble - nearest galaxy is Andromeda 2.5M light years 26'
      • contains a trillion stars
  • non-euclidian geometry
  • expanding universe 45'
    • hubble blue / red shifts 46'
    • fabric of space in between galaxies is expanding 47'
    • einstein 'cosmological constant was biggest mistake'
    • big bang 47'
      • flash of light from big bang fills universe - CMB - see on TV 49'
      • fossilised light of the first dawn 13.7 billion years old 51'
        • why it gets dark at night 52'
          • universe is not infinitely old
  • dark energy origin of expansion of universe 57'


The second part, Nothing, explores science at the very limits of human perception, where we now understand the deepest mysteries of the universe lie. Jim sets out to answer one very simple question - what is nothing? His journey ends with perhaps the most profound insight about reality that humanity has ever made. Everything came from nothing. The quantum world of the super-small shaped the vast universe we inhabit today, and Jim can prove it.'

Summary of Part 2, Nothing
  • what is nothing?
    • emptiness is what most of the universe is made up of
      • void or vacuum
  • 14 billions years ago the universe appeared out of nothing 3'
  • Aristotle
    • nothingness was paradoxical, 'nature abhors a vacuum'
    • Torricelli  experimented and showed Aristotle was wrong - he created empty space, atmosphere has a specific weight 5'
      • we live at the bottom of an ocean of air
      • Blaise Pascal - nothing is everywhere - 10'
        • a vacuum is natures default state
        • light travels through a vacuum (but not sound which is carried by air) - 11'
      • Albert Michelson - measured speed of light 
      • Albert Einstein
        • ether does not exist  - 20'
  • TV / lightbulb / computer valves - contain vacuum
  • X Ray / electron / atom discovered 25'
  • quantum mechanics 25' 
    • nothing is not possible
    • Heisenberg Uncertainty Principle 26'
      • nature is based on uncertainty
      • cannot know exactly position in space and time at quantum level 29'
      • create something out of nothing, provided something disappears immediately 31'
  • Paul Dirac 33'
    • a 'dirac' - unit of shyness!
    • Dirac Equation: unified special relativity and quantum mechanics, described electron 36'
      • anti-electron (mirror of electron)
      • made out of vacuum: anti-matter collides with matter; all mass is turned into energy and mass disappear completely 43'
      • whenever particle pops out of empty space so simultaneously does its anti-particle 44'
      • vacuum goes from nothing to teaming with trillions [Dirac Sea] of pairs of matter-antimatter particles which appear and disappear (virtual particles) 45'
  • Quantum shapes the structure of the universe, nothing has shaped everything 51'
    • embryonic universe temperature variations are scars of quantum vacuum 53'
    • matter did not spread out evenly, clumps of quantum irregularities of  the vacuum give galaxies 54'
    • in big bang for every billion particles of matter and anti-matter anialated one particle of matter was left, radiation, gave rise to heat of big bang and CMB. 56'
    • connection between the nothing from which we were created and the infinite in which we are engulfed 59'

No comments: