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Albert’s Cow and Special Relativity:Albert s Cow and Special Relativity:A Layman’s Introduction (Almost) Without Mathematics

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Dani Censor This is a popular introduction to SR, for laymen, motivated by being exposed to too many bogus TV programs about the wonders of modern physics withouttoo many bogus TV programs about the wonders of modern physics, without any attempt to explain any of these wonders. The presentation does not go beyond high school junior class physics and mechanics, and mathematics involving two simple equations with two unknowns. The motivation comes f li t i t l t lk b t i bj t d th t tfrom listening to popular talks about various subjects, and the constant questioning: “and what were you doing before you retired?” At this stage I usually start to wave my arms energetically, and comment how radio waves are important to cellular telephony.

Many images and some explanations found on the internet are used. Trying to get approval from all these sources would take years. So here is a collective “thank you”, and an apology for not giving detailed credit, but this humble presentation is not for publication anyhow.

The explanations are honest, although not all the details are meticulouslyexplained. So there are here lies of the kind “suppressio veri” but not “suggestio falsi “. My apologies.

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Ali f ll d th h ft i th ti h hAlice falls down the shaft… is the time she sees when moving towards the clock…

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… the same as the time she would see at the clock if she stopped falling?

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th ti h h f lli…or the time she sees when falling awayfrom the clock?

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common origin: 0 0 0 0c c

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Baron Munchausen - The Cannonball Ride29

Baron Munchausen The Cannonball Ride

  There was a young lady named Bright who traveled much faster than light.

She started one dayShe started one dayin the relative way,

and returned on the previous nightand returned on the previous night.

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Karl Popper

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Michelson-Morely

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Kinematics=Space and Time relations

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2

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2( )t t V

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All traced back to Einstein’s postulate: c constantAll traced back to Einstein’s postulate: c=constant Dynamics=Mechanics, Electromagnetic, etc. involving Material Objects Postulate needed: “Laws of nature are invariant (same for all observers)”Postulate needed: Laws of nature are invariant (same for all observers) BUT WHAT DOES “LAW OF NATURE” MEAN???

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BUT WHAT DOES “LAW OF NATURE” MEAN???

Edict by Divine Inspiration???

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Genesis 8:22 (Hebrew Bible) “ הארץכלעד וחרף:ימי וקיץ וחם וקר וקציר ולילהזרע --ויום ולילה,זרע וקציר וקר וחם וקיץ וחרף: ימי הארץ-כל,עד (Hebrew Bible)ויום ”לא ישבתו

Whil th th i th dti d h t(King James Version) While the earth remaineth, seedtime and harvest, and cold and heat, and summer and winter, and day and night shall not cease.

(Simple English) “As long as the earth exists, sowing and harvest, cold and heat, summer and winter, day and night, will never cease.”, , y g , (Turkish) “Sürece toprak kutsal sayılmaktadır. ekim ve hasat soğuk ve sıcağa yaz ve kış gece ve gündüz ateşkes asla ”sıcağa, yaz ve kış, gece ve gündüz ateşkes asla.

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“Psst… 02

21

mmVc

”

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c

“Psst…2 2 2 4

0( )E p c m c ”

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“P P P P l !!!“Psst… Posst… Postu… Postulate!!!

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Popperian falsificationism610

Newton: 1/ , 2

Censor: 1/ , 2.000...01

F r

F r

Ce so : / , . ...Anonymous: 1/ , 3

by everyday phenomena,RefutedF r

e.g., Kepler laws of planetary mo oti n.

Occam's (or Ockham's) razor, Latin:lex parsimoniae, law of parsimony.

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“Psst… Postulate: 02

1

mmV

”

21c

l i l b 22

2 0m cMultiply by 2c , 2 02

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m cmcVc

c

Approximate the denominator 2 2 21

Ahaa! I see the light2 2 2

0 01 ... (higher terms)2

mc m c m V

21Interpretation: 20

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m V classical kinetic energy2E mc total energy 2E m c rest energy

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E mc total energy, 0 0E m c rest energy.

Cockroft and Walton Experiment Converting Mass into EnergyConverting Mass into EnergyIn 1932, the English physicist John Cockroft and the Irish physicist Ernest Walton produced a nuclear disintegration by bombarding Lithium with artificially accelerated protons.

The following reaction took place:

This was the first artificial splitting of a nucleus. It was also the first transmutation using artificially accelerated particles. y p

Protons were accelerated and slammed into lithium atoms producing alpha-particles and energy. Thus the mass of the proton and lithium was converted into the mass of two alpha-particles and kinetic energy.kinetic energy.

This reaction was the first experimental proof of Einstein's E = mc^2

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THIS IS ALL, FOLKS, THANK YOU

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