Motion Mountain - The Adventure of Physics, Vol 3 of 6 - Light, Charges and Brains

330 Pages·2011·38.27 MB·English

by  Christoph Schiller

Christoph Schiller
MOTION MOUNTAIN
the adventure of physics – vol.iii
light, charges and brains
www.motionmountain.net

ChristophSchiller
Motion Mountain
The Adventure of Physics
Volume III
Light, Charges and Brains
Edition24.24,available asfreepdfat
www.motionmountain.net
Editiovicesimaquarta.
Proprietasscriptoris©ChrestophoriSchiller
tertioannoOlympiadisvicesimaenonae.
Omniaproprietatisiurareservanturetvindicantur.
Imitatioprohibitasineauctorispermissione.
Nonlicetpecuniamexpetereproaliquo,quod
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proomnibussempergratuituseratetmanet.
Twenty-fourthedition.
Copyright©2010byChristophSchiller,
thethirdyearofthe29thOlympiad.
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ToBritta,EstherandJustusAaron
τῷἐμοὶδαὶμονι
DieMenschenstärken,dieSachenklären.
PREFACE
“Primummovere,deindedocere.* ”
Antiquity
This book is written for anybody who is curious about nature and motion. Curiosity
M
o
about how people, animals, things, images and space move leads to many adventures. tio
n
Thisvolumepresentstheadventuresoneencounterswhenexploringeverythingelectric. Mo
u
n
The story ranges from the weighing of electric current to the use of magnetic fields to tain
healbonefracturesanduptotheunderstandingofthehumanbrain. –Th
e
In the structure of physics, shown in Figure 1, motion due to electricity is the most A
d
ve
fascinatingaspectofthestartingpointatthebottom.Indeed,almosteverythingaround ntu
us is due toelectric processes.The presentintroductionto electricity,magnetism, light reo
f
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aanimdtthheatbIrahianviespthuerstuheidrdsoinfcaes1i9x9-v0o:ltuompereosveenrtvmieowtioofnpihnyasicwsatyhtahtaatroissesifmropmle,autphrteoedfoaltde hysics
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andcaptivating. f
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necIenssoarrdyermtionbimeusimm.plUe,ntdheerstetaxntdfoincgustehseocnocnocnecpetpstos,fwphhyilseickseeispignigvemnapthreecmedateincscetootvheer availab
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usingformulaeincalculations.Thewholetextiswithinthereachofanundergraduate. free
o
Inordertobeuptodate,thetextisenrichedbythemanygems–boththeoreticaland fch
empirical–thatarescatteredthroughoutthescientificliterature. arg
e
Inordertobecaptivating,thetexttriestostartlethereaderasmuchaspossible.Read- atw
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ing a book on general physics should be like going to a magic show. We watch, we are w.m
o
astonished, we do not believe our eyes, we think, and finally we understand the trick. tio
n
m
Whenwelookatnature,weoftenhavethesameexperience.Indeed,everypagepresents o
u
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atleastonesurpriseorprovocationforthereadertothinkabout.Numerousinteresting tain
.n
challengesareproposed. et
C
Themottoofthetext,dieMenschenstärken,dieSachenklären,afamousstatementby o
p
HartmutvonHentigonpedagogy,translatesas:‘Tofortifypeople,toclarifythings.’Clar- yrig
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t
ifyingthingsrequirescourage,aschanginghabitsofthoughtproducesfear,oftenhidden ©
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byanger.Butbyovercomingourfearswegrowinstrength.Andweexperienceintense risto
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and beautifulemotions.Allgreatadventuresin life allow this, and exploringmotion is h
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oneofthem. iller
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Munich,24June2011. vemb
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*‘Firstmove,thenteach.’Inmodernlanguages,thementionedtypeofmoving(theheart)iscalledmotivat- ne
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ing;bothtermsgobacktothesameLatinroot. 01
1
8 preface
PHYSICS: Unified description of motion Why does motion
Describing motion with action. Adventures: understanding occur? What are
motion, intense joy with space, time and
thinking, catching a quantum particles?
glimpse of bliss,
calculating
masses and
couplings.
Quantum
General relativity theory with gravity Quantum field theory
Adventures: the Adventures: bouncing Adventures: building
night sky, measu- neutrons, under- accelerators, under-
ring curved space, standing tree standing quarks, stars,
exploring black growth. bombs and the basis of
holes and the life, matter, radiation. Mo
universe, space How do small tionM
and time. things move? ou
n
What are things? tain
–
How do The
Classical gravity everyday, Special relativity Quantum theory Adve
Adventures: fast and large Adventures: light, Adventures: death, ntu
climbing, skiing, things move? magnetism, length sexuality, biology, reo
f
space travel, contraction, time enjoying art and P
h
the wonders of dilation and colours, all high-tech ysics
astronomy and E0 = mc2. business, medicine, pd
geology. chemistry, evolution. ffi
le
G c h, e, k availab
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Galilean physics, heat and electricity freeo
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Adventures: sport, music, sailing, cooking, ch
describing beauty and understanding its origin, arge
using electricity and computers, atw
w
understanding the brain and people. w
.m
o
FIGURE 1 Acompletemapofphysics:theconnectionsaredefinedbythespeedoflightc,the tion
m
gravitationalconstantG,thePlanckconstanth,theBoltzmannconstantkandtheelementarychargee. ou
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Advice for learners pyrig
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©
Inmyexperienceasateacher,therewasonelearningmethodthatneverfailedtotrans- Ch
form unsuccessful pupilsintosuccessful ones: if you readabook for study, summarize ristop
h
every section you read, in your own words, aloud. If you are unable to do so, read the Sch
section again. Repeat this until you can clearly summarize what you read in your own iller
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words,aloud.Youcandothisaloneinaroom,orwithfriends,orwhilewalking.Ifyou vem
b
dothiswitheverythingyouread,youwillreduceyourlearningandreadingtimesignif- er
1
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icantly. In addition, you will enjoy learning from good texts much more and hate bad 97
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textsmuchless.Mastersofthemethodcan use itevenwhilelisteningtoalecture,ina Jun
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2
lowvoice,thusavoidingtoevertakenotes. 01
1
preface 9
Using this book
Textingreen,asfoundinmanymarginalnotes,marksalinkthatcanbeclickedinapdf
reader. Such green links are either bibliographic references, footnotes, cross references
tootherpages,challengesolutions,orpointerstowebsites.
Solutionsandhintsforchallengesaregivenintheappendix.Challengesareclassified
as research level (r), difficult (d), standard student level (s) and easy (e). Challenges of
typer,dorsforwhichnosolutionhasyetbeenincludedinthebookaremarked(ny).
Feedback and support
This text is and will remain free to download from the internet. In exchange, I would
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followingissues: Mo
tio
n
Challenge1s — Whatwasunclearandshouldbeimproved? Mo
u
n
— Whatstory,topic,riddle,pictureormoviedidyoumiss? tain
— Whatshouldbecorrected? –Th
e
A
d
Alternatively,youcanprovidefeedbackonline,onwww.motionmountain.net/wiki.The ve
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feedbackwillbeusedtoimprovethenextedition.Onbehalfofallreaders,thankyouin ture
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