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This page and all subsidiary pages or files are copyright © 1996 Leonard Cottrell.

Table of Contents

• the Planck units:
  • intent
  • a range of quantities for comparison
  • why look at Planck quantities?
  • profoundly ordinary
  • involvement with everyday experience
  • connection with gravitational length
  • the day you reach the billion mark
  • other cultures from an 1899 perspective
  • the universal impulse
  • the role of humanly scaled versions
• the earth as a threepenny planet:
  • lengths describing gravity
  • measuring gravitational length
  • connecting gravitational length and Planck quantities
  • where gravilengths are more accurate than inertias
  • sample calculations with gravitational length
  • gravitational length and baryon number
• measuring and visualizing Planck quantities:
  • logging Planck speed
  • gauging Planck force
  • the split-beta-fourth ratio of forces
  • access to Planck charge--the solid state electron counter
  • access to Planck length as a geometric mean
  • bluer light overcomes a higher voltage
  • experience of Planck time and length
  • visualizing Planck force and Planck power
  • fractions of Planck power as light
  • instances of the Planck heat capacity
• naming the humanly scaled set:
  • reminder of intent
  • Planck quantities scaled for direct perception
  • semisecond
  • mile
  • gallon
  • span
  • stone
  • spanstone
  • dram
  • volt
  • amber
  • eevee
  • degree
• advantages of the humanly scaled set:
  • c e k-mate--ease of reckoning
  • coherence resulting from exact powers-of-ten
  • sample coherence: Compton effect and Chandrasekhar limit
  • simple values of Planck quantities
  • clear constants in Planck terms
  • transparency in humanly scaled terms
  • case study: basic numbers in an ionization energy
  • another example: the energy of an electron's being
• how exact constants come about:
  • exact constants in the metric context
  • exact constants in our context--imitating the Bureau
  • exact constants seen as a trend
• conversion factors:
  • official metric factors courtesy of CODATA
  • connecting our units with the 1990 electrical standards
• amber and lodestone:
  • quote from Jackson's Classical Electrodynamics
  • expert avoidance of metric units
  • balanced versus unbalanced forms of Maxwell's equations
  • the metric permies
  • "the essential asymmetry of the sources"
  • the metric variant including sources
  • the spine of a current
  • metric etiquette: using the right permie
  • volts per span is intuitive--using a single field unit
  • coherence is another advantage
  • an electric field of routine interest
• mole:
  • a mole is 10--a deep breath is a mole
  • how to weigh out a mole in the lab
  • the Avogadro hypothesis and standard conditions
  • breathing after a climb
• a firmer grip:
  • reduced uncertainty with humanly scaled Planck units
  • based on CODATA recommended values
  • the metric handicap
• chance agreements:
  • Prague is rounding the turn at Mach one: [ c ]
  • the multitude in a breath: [# / ]
  • the light on the land: 0.98 [ / ]
  • the midday speed to the west: 0.99 [ c ]
  • the average color of sunlight: 1.1 [ ]
  • ninetysix quivers of sunshine in Planck time: 0.96 [# / ]
  • the sun's radiance: 1.06 [ ]
  • the mass of a black hole as hot as the sun: 0.98 [ ]
  • the heft of terrestrial stuff: 1.07 [ / ]
  • the upchill sufficient for wind: 1.1 [ / ]
  • the speed of sound: [ c ]
  • pacing the toss-up
  • a leather hat, useful for carrying water
  • nanospan nanostone, a rule of Planck thumb
  • a trail of likenesses of alpha centauri
  • stars do not come much Plancker than the sun
  • the electron's voltage makes a spanish spark
  • wavelength in span is cyclelength in meters divided by 1.02
  • a speed the dish watches: 1.03 [ c ]
  • the price of an electron's freedom: 1.1 [ ]
• a durable perspective:
  • reckoning with long-lasting numbers
  • examples of mantissa-calculations
  • useful skepticism
  • mindfulness of cultural inertia
  • perspective going beyond particular linguistic choices
  • non-appearance of the Planck set in general physics courses
• the convenience playoffs:
  • competitive comparison is not really necessary
  • what didn't go wrong, or went unexpectedly right
  • no guaranteed convenience, as the second shows
  • a cubic meter is clumsy in a way that a gallon is not
  • our speed scale has decimal benchmarks
  • our mole and its volume are easily recalled
  • practical electric units with a memorable constant or two
  • our force is recognizable
  • convertibility and improved precision
  • technicality concerning the definition of Planck quantities
  • the humanly scaled unit of inertia
• some alternative formulations of physical law:
  • extending the range of expression
  • example of Hawking temperature
  • recalling the chapter on gravitational length