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Proton mass (was: More Physics Heresay)

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Y.Porat wrote:

>  > ACK.
>   Mu.

“Mu” is the correct answer to a wrong/nonsensical question.  “ACK” is not 
even a question.  You have omitted the attribution lines, and you have 
mangled the quotation of my posting further.  Learn to quote.

>> > An electron has 3 times the charge of a down quark
>> 
>> Correct.
>> 
>> > yet it is at least 3 times lighter.
>> 
>> The electron has a mass that is less than 1∕9 of the mass of the down
>> quark.
> 
> so
>  3  down quark has 3 times 9    times electron  mass

Approximately, yes.  AISB, the electron mass is *less than* 1∕9 of the down 
quark mass (m_e < 1∕9 m_d), meaning that the down quark mass is *more than* 
9 times the electron mass (9 m_e < m_d).

> ie
> 3 down Qarks =Proton ??

No, a proton has electric charge +1 e, so (for that reason alone) if it is a 
non-exotic hadron (and it is) then it must consist (among other stuff with 
zero electric charge, see below) of 2 up quarks (q_u = +⅔ e) and 1 down 
quark (q_d = −⅓ e) as ⅔ + ⅔ − ⅓ = 1.  (Again, simple arithmetic.)

> so
> 9
> times  electron mass = quark mass

For up quark and down quark, slightly more (for e.g. a top quark, 
considerably more).  But in nature there are no single quarks, …
 
>   3 quarks = 27 times Electron mass

… so this calculation is approximately valid only for quarks at rest in the 
QCD vacuum (if one assumes light quarks and that you have meant “≈” instead 
of “=”).
 
> 27 times 0.00045 = 0.01215 AMU

The electron mass is 5.4857990946(22) × 10⁻⁴ u ≈ _0.00055_ u instead.
(What references and units are you using?)

<https://en.wikipedia.org/wiki/Electron>
<http://physics.nist.gov/constants>
<http://pdg.lbl.gov/2015/listings/rpp2015-list-electron.pdf>

> !!(about one percent )!! OF Proton mass ??????!!

The rounded result (1 %) is correct (AISB several times); the calculation is 
not.

>  (1.000 AMU)

[I assume in the following that you mean “atomic mass unit” by “AMU” with 
the old unit symbol in uppercase, but based on carbon.  Previously, “amu” 
was based on oxygen, but this unit was replaced with “u” based on carbon,
in 1961 CE.  So I assume 1 AMU = 1 u.]

A proton does not have a mass of 1.000 u (atomic mass unit; symbol: _u_).
1 u is defined as “the mass of an unbound neutral *atom* of carbon-12 in 
its nuclear and electronic ground state” (emphasis mine), which has 6 
protons, 6 neutrons, and 6 electrons each which has kinetic energy, too.

Compare:

  1 u = 1.660 539 040(20) × 10⁻²⁷ kg

   mₚ = 1.672 621 898(21) × 10⁻²⁷ kg

<https://en.wikipedia.org/wiki/Atomic_mass_unit>
<http://pdg.lbl.gov/2015/listings/rpp2015-list-p.pdf>

> WHERE the HECK IS THE  OTEHER 99 PERCENT OF PROTON MASS !!!
> ????

Uh-oh.  You crackpots reading this have to be really strong now: Special 
relativity and quantum mechanics, i.e. quantum electrodynamics (QED), 
provide the correct answer, exact “to ten decimal places” (Lawrence Krauss; 
see the video URL below).

Because the other 99 % of the proton mass is in the energy of the “empty 
space between the quarks” (AISB) “where virtual particles are popping in and 
out of existence in a timescale so short you can’t see/measure them”.

Or, more precisely, it is in the kinetic energy of the quarks *and*, most of 
all, the total energy (rest energy = 0 and kinetic energy > 0) of the 
virtual gluons that can transfer color charge from one quark to the other.  
(Virtual particles are not observables, hence “you can’t see/measure them”.  
But “we can measure their effects indirectly”.)

Because the mass of a proton is equivalent to its rest energy (m = E₀∕c²; 
Einstein 1905: “Does the inertia of a body depend on its energy content?”), 
and that comes from the *total* energy of each of its constituents:

  E = √((m c²)² + (p c)²)

  p = {γ m v  if m > 0 (as with quarks) – Einstein (SRT)
      {ℎ∕λ    if m = 0 (as with gluons) – DeBroglie hypothesis, confirmed
                                          by the Davisson–Germer experiment

  γ = 1∕√(1 – (v∕c)²)

  where

  E – total energy of constituent
  m – (rest) mass of constituent
  c – speed of light in vacuum
  p – relativistic momentum of constituent
  γ – Lorentz factor
  v – speed of a constituent relative to an observer at rest relative to
      the considered system (here: a proton)
  ℎ – Planck constant
  λ – wavelength of constituent

<https://www.nobelprize.org/educational/physics/matter/9.html> pp.
<https://en.wikipedia.org/wiki/Strong_interaction#/media/File:Nuclear_Force_anim_smaller.gif>
<https://en.wikipedia.org/wiki/Proton#Quarks_and_the_mass_of_a_proton>
<https://youtu.be/sbsGYRArH_w?t=2251>

HTH.

BTW, your keyboard *still* is in *desperate* need of repair, and you should 
really get a first name.

-- 
PointedEars

Twitter: @PointedEars2
Please do not cc me. / Bitte keine Kopien per E-Mail.

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Thread

More Physics Heresay Michael J. Strickland <michael06582@comcast.net> - 2016-07-21 03:05 -0400
  Re: More Physics Heresay Alan Folmsbee <omnilobe@gmail.com> - 2016-07-21 02:15 -0700
  Re: More Physics Heresay Sergio <invalid@invalid.com> - 2016-07-21 10:22 -0500
  Re: More Physics Heresay Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-07-24 18:18 +0200
    e.e hearsay, here said ... that sylli poet? noTthaTguY <abu.kuanysh05@gmail.com> - 2016-07-25 19:59 -0700
      Re: e.e hearsay, here said ... that sylli poet? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-07-26 07:39 +0200
    Re: More Physics Heresay "Y.Porat" <y.y.porat@gmail.com> - 2016-07-26 01:08 -0700
      Proton mass (was: More Physics Heresay) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-07-26 15:35 +0200
        Re: Proton mass Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-07-26 17:05 +0200
          Re: Proton mass john <johnsefton288@gmail.com> - 2016-07-26 08:09 -0700
    Negative mass (was: More Physics Heresay) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-07-31 09:05 +0200
  Re: More Physics Heresay Sylvia Else <sylvia@not.at.this.address> - 2016-07-26 13:03 +1000
  Re: More Physics Heresay Yousuf Khan <bbbl67@spammenot.yahoo.com> - 2016-07-26 12:43 -0400
    Re: More Physics Heresay Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-07-26 20:31 +0200
      Re: More Physics Heresay noTthaTguY <abu.kuanysh05@gmail.com> - 2016-07-26 11:57 -0700
    Re: More Physics Heresay Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-07-31 09:07 +0200
      Re: More Physics Heresay ben6993 <ben6993@hotmail.com> - 2016-08-01 00:19 -0700
  Re: More Physics Heresay ben6993 <ben6993@hotmail.com> - 2016-07-26 15:10 -0700
    more sloganeers noTthaTguY <abu.kuanysh05@gmail.com> - 2016-07-27 12:19 -0700
      Re: more sloganeers noTthaTguY <abu.kuanysh05@gmail.com> - 2016-07-28 14:26 -0700

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