work out the speed of light by making cheese on toast.

source: http://www.youtube.com/watch?v=_t0EgviIbR0

HASSNERS.org highlights

HASSNERS.org comments

41:04 - Dara O'Briain works out the speed of light by making cheese on toast.

A microwave travels at the speed of light.

speed of light = frequency x wavelength

6.5cm between hot spots of cheese x 2 = wavelength = 13cm = 0.13metres

frequency (from back of microwave) = 2450 MHz = 2.45 x 109 giga hertz
calculated speed of light = 0.13m x 2.45 x109 = 3.2 x 108 m/s

Actual speed of light is 3.0 x 108 m/s (300,000 km/s=3 x 105 km/s)

Pretty close, eh!

Marcus Brigstocke investigates 'Nothing'

source: http://www.youtube.com/watch?v=_t0EgviIbR0

From 17:45s:
Marcus Brigstocke investigates 'Nothing' with Jim Al-Khalili  in Dara O Briain's Science Club:

Einsteins' theory of relativity proved that the aether did not exist. In space there are photons flying about everywhere. Between two electrons there are photons being emitted.

Nothing does not exist (20:34). Empty space is filled with forces (20:51), for example the force of gravity is something which Einstein thought was pulling everything together. We now know that 'vacuum energy' is making the universe expand faster and faster outwards. (21:22).

(NB. One contribution to the vacuum energy are from virtual particles - particle pairs that blink into existence and then annihilate in a timespan too short to observe. They are expected to do this everywhere, throughout the Universe.)

A cloud chamber demonstrates electrons and anti-electrons which have come from outer space (22:30).'

Bob Nichol: 'The universe is accelerating in its expansion'. The expansion is caused by 'dark energy' (24:00) a term for anything that could be causing this expansion - the most favoured explanation is 'vacuum energy'.

[According to a 2003 theory] eventually galaxies will move away from each other faster than the speed of light. (24:39) In about 60 billion years the 'Big Rip' [quintessence in which dark energy destabilises] could occur and space itself might dismantle (it will be the end of the universe - all atoms will be destroyed) (24:44).

Fields permeate empty space:- Electric, magnetic, higgs and gravitational fields. Neutrinos are elementary subatomic particles which pass through us from space. (Janna Levin 25:58s)

http://scienceblogs.com/startswithabang/2011/05/16/the-fate-of-the-universe/

http://scienceblogs.com/startswithabang/2011/05/16/the-fate-of-the-universe/

Pew Forum: In USA One-in-Five Adults Have No Religious Affiliation

source and Full pdf Report. My comments in blue.

Some of the religiously unaffiliated (excluding atheists and agnostics) are religious or spiritual in some way, pray each day, feel a deep connection with nature and the earth and are “spiritual” but not “religious”. A mixed bunch!

• "The number of Americans who do not identify with any religion continues to grow at a rapid pace. One-fifth of the U.S. public – and a third of adults under 30 – are religiously unaffiliated today, the highest percentages ever in Pew Research Center polling."
• "In the last five years alone, the Religiously Unaffiliated have increased from just over 15% to just under 20% of all U.S. adults. Their ranks now include more than 13 million self-described atheists and agnostics (nearly 6% of the U.S. public), as well as nearly 33 million people who say they have no particular religious affiliation (14%)"

• "This large and growing group of Americans (the religiously unaffiliated) is less religious than the public at large on many conventional measures, including frequency of attendance at religious services and the degree of importance they attach to religion in their lives."
• "many of the country’s 46 million unaffiliated adults are religious or spiritual in some way. Two-thirds of them say they believe in God (68%) though less than half say they are absolutely certain of God’s existence." ie these are NOT the Atheists & Agnostics. 
• "More than half say they often feel a deep connection with nature and the earth (58%)"
• "more than a third classify themselves as “spiritual” but not “religious” (37%)"
• "one-in-five (21%) say they pray every day" (!!)

• "The growth in the number of religiously unaffiliated Americans – sometimes called the rise of the “nones” – is largely driven by generational replacement, the gradual supplanting of older generations by newer ones. A third of adults under 30 have no religious affiliation (32%), compared with just one-in-ten who are 65 and older (9%). And young adults today are much more likely to be unaffiliated than previous generations were at a similar stage in their lives."

• "most religiously unaffiliated Americans think that churches and other religious institutions benefit society by strengthening community bonds and aiding the poor"
• "typically the unaffiliated say they are not looking for a religion that would be right for them"
• "Overwhelmingly, they think that religious organizations are too concerned with money and power, too focused on rules and too involved in politics"

Pew - The Global Religious Landscape - The Religiously Unaffiliated

Source and pdf - Published: The Global Religious Landscape, December 18, 2012

Summary

• one-in-six people around the globe (1.1 billion, or 16%) have no religious affiliation
• the unaffiliated are the third-largest religious group worldwide, behind Christians and Muslims, and about equal in size to the world’s Catholic population
• Three-quarters of the religiously unaffiliated (76%) live in the Asia- Pacific region
• most religiously unaffiliated people (71%) live in countries in which they are the predominant religious group
• The Religiously Unaffiliated includes atheists, agnostics and people who do not identify with any particular religion in surveys. However, many of the religiously unaffiliated do hold religious or spiritual beliefs.
• More than six-in-ten (62%) of all religiously unaffiliated people live in one country, China
• There are six countries where the religiously unaffiliated make up a majority of the population

More

• "Pew Forum finds that roughly one-in-six people around the globe (1.1 billion, or 16%) have no religious affiliation. The religiously unaffiliated include atheists, agnostics and people who do not identify with any particular religion in surveys. This makes the unaffiliated the third-largest religious group worldwide, behind Christians and Muslims, and about equal in size to the world’s Catholic population." (source: pdf, pg 9)

• "Many of the religiously unaffiliated have some religious beliefs. For example, belief in God or a higher power is shared by 7% of Chinese unaffiliated adults, 30% of French unaffiliated adults and 68% of unaffiliated U.S. adults. Some of the unaffiliated also engage in certain kinds of religious practices. For example, 7% of unaffiliated adults in France and 2 7% of those in the United States say they attend religious services at least once a year. And in China, 44% of unaffiliated adults say they have worshiped at a graveside or tomb in the past year. Beliefs and practices of unaffiliated adults in the United States are documented in the Pew Forum’s October 2012 report “ ‘Nones’ on the Rise.” (source: pdf, pg 24)

• "Three-quarters of the religiously unaffiliated (76%) live in the Asia- Pacific region. The number of religiously unaffiliated people in China alone (about 700 million) is more than twice the total population of the United States." (source: pdf, pg 10)

• ''most religiously unaffiliated people (71%) live in countries in which they are the predominant religious group. The religiously unaffiliated make up a majority of the population in six countries, of which China is by far the largest. The others are the Czech Republic, Estonia, Hong Kong, Japan and North Korea." (source: pdf, pg 11)

• "The Religiously Unaffiliated includes atheists, agnostics and people who do not identify with any particular religion in surveys. However, many of the religiously unaffiliated do hold religious or spiritual beliefs. eg Belief in God or a higher power is shared by 7% of unaffiliated Chinese adults, 30% of unaffiliated French adults and 68% of unaffiliated U.S. adults". See Note 6 below (source: pdf, pg 15)

(source: pdf, pg 9)

Religiously Unaffiliated

(source: pdf, pg 12)

Census 2011: 25.1% of England & Wales population are religiously unaffiliated (No religion).

• There are six countries where the religiously unaffiliated make up a majority of the population: the Czech Republic (76% are religiously unaffiliated), North Korea (71%), Estonia (60%), Japan (57%), Hong Kong (56%) and China (52%). 
• 16.4% of the total U.S. population was unaffiliated as of 2010. As of 2012, 19.6% of U.S. adults are unaffiliated. (source: pdf, pg 25-26)

(source: pdf, pg 25)

(source: pdf, pg 25)

More than six-in-ten (62%) of all religiously unaffiliated people live in one country, China. The largest populations of the religiously unaffiliated outside China are in Japan (6% of all unaffiliated), the United States (5%), Vietnam (2%) and Russia (2%). (source: pdf, pg 25-26)