Humanists4Science: BBC - Everything and Nothing

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.

Everything

Summary

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

Gauss, Reimann, einstein

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'

Nothing

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'

light must be carried by luminiferous 'ether' - 12'

Albert Michelson - measured speed of light

speed of light should differ if ether exists - 15'

Michelson & Edward Morley - speed of light is constant

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 Field Theory 46'
Willis Lamb - proves activity in nothingness 48'
electron is wobbled by the vacuum which has an energy

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'

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About Humanists4Science (Hum4Sci)

Humanists4Science (H4S) Mission "To promote, within the humanist community, the application of the scientific method to issues of concern to broader society."

H4S Vision "A world in which important decisions are made by applying the scientific method to evidence rather than according to superstition."

H4S is for humanists with an active interest in science. We believe that science is a fundamental part of humanism but also that it should be directed to humane and ethical ends. Science is, in our view, more a method than a body of facts.

H4S take a naturalistic view and believe, like 62% of the UK population, that science, the scientific method & other evidence provides the best way to understand the universe.

H4S are a Special Interest Group of the British Humanist Association (BHA).

Since 2008 H4S members have discussed many Humanist-Science topics in our Yahoo Group.

Prof. Jim Al-Khalili - 11TH BHA President - On Scientific Method

'I have a rational unshakeable conviction that our universe is understandable, that mysteries are only mysteries because we have yet to figure out, the almost always logical answers. For me there is simply no room, no need, for a supernatural divine being to fill in the gaps in our understanding. We’ll get there, we’ll fill in those gaps with objective scientific truths: [with] answers that aren't subjective, because of cultural or historical whims or personal biases, but because of empirically testable and reproducible truths. We may not get the full picture, we may never get the full picture, but science allows us to get ever closer.’ Jim Al-Khalili, BHA AGM 2013

"A lot of people say science is just one way of looking at the world, at reality, and poets and musicians and, of course, people of faith, have said there are other ways. I don't buy that. For me there is an objective reality that is there and real. For a theoretical physicist who's trained in thinking about quantum mechanics, which involves the idea that by observing something you alter its nature, you have to have some sort of working definitions of reality"
Jim Al-Khalili in New Humanist magazine Mar Apr 2013

Lord Taverne

Science depends on reason and regard for evidence. For me, the scientific approach lies at the heart of humanism as well as atheism. We all accept that science has made us healthier and wealthier. What has been seldom acknowledged or realised is that since the Enlightenment, which it helped to bring about, science has played an essential part in making us more civilised.

Science is the enemy of autocracy because it replaces claims to truth based on authority with those based on evidence and because it depends on the criticism of established ideas. Scientific knowledge is the enemy of dogma and ideologies and makes us more tolerant because it is tentative and provisional and does not deal in certainties. It is the most effective way of learning about the physical world and therefore erodes superstition, ignorance and prejudice, which have been causes of the denial of human rights throughout history. Science is also the enemy of narrow nationalism and tribalism and, like the arts, is one of the activities in this world that is not motivated by greed.

What can compare, for example, with the recent achievement of the Large Hadron Collider, a venture of collaboration by 10,000 scientists and engineers from 113 countries, free from bureaucratic and political interference? Those people put aside all national, political, religious and cultural differences in pursuit of truth and for the one purpose of exploring and understanding the natural world.

Without the contribution of science, which is, in my view, the rock on which atheism and humanism are built, we would be less inclined to be critical, tolerant and understanding and more prone to prejudice, bigotry and tribalism. We would be a less civilised society.

Lord Taverne, 25th July 2013, House of Lords debate on contribution of Humanism and Atheism

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Sunday, 17 April 2011

BBC - Everything and Nothing - Jim Al-Khalili

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