Discussion:
Quarks are obsolete
(too old to reply)
Thomas 'PointedEars' Lahn
2018-06-29 02:05:58 UTC
Permalink
Quark experimental basis was 3 jets of hadrons.
Only in the broadest possible sense. Instead, like before with the atom,
the observed scattering off nucleons (which are also hadrons) did not
correspond to the previous idea that nucleons would be elementary particles.

Take for example the proton. We knew before:

Q_p = +1 e,

and thought it would be like this:

. '+' .
' + + + '
:+ + + + +:
. + + + ,
`-.+.-'

So this should have been observed:

Elementary nucleon model (postulated in 1815, confirmed in 1917,
falsified in 1968+)

^ ^ ^
\ : .'
(+)-----\>. '+' . (−)------>.''+' .
(+)----->' + + + ' (−)----->' + + + '
(+)<--->:+ + + + +: (−)---->:+ + + + +:
(+)----->. + + + , (−)----->. + + + , __
(+)-----/>` .+. ' (−)------>`..+. ' |PE
/ : `.
v v v

Instead, this is observed:

Quark model (postulated in 1964, confirmed in 1968+)

(+)-------.-'-'-.------> (−)-------.-'-'-.------->
(+)<----->(?) (?)' (−)------>(?) (?)'
(+)-----:---------:----> (−)-----:---------:----->
(+)------.->(?) , (−)<------->(?) , __
(+)-------`-.-.-'------> (−)-------`-.-.-'-------> |PE

So we know now:

p ≡ uud

. ' ' .
'(+) (+)'
: :
. (−) ,
` . . '

And the math gives as the total charge the known numbers, too:

Q_p = 2 × Q_u + Q_d = 2 × (+2∕3 e) + (−1∕3 e) = +1 e.

Likewise the neutron:

n ≡ udd

. ' ' .
'(+) (−)'
: :
. (−) , __
` . . ' |PE

Q_n = Q_u + 2 × Q_d = (+2∕3 e) + 2 × (−1∕3 e) = 0 e.

And we know (experimentally) that there are mesons, too. For example, the pion:

π⁺ ≡ ud̅

. ' ' .
' (+) '
: :
. (+) ,
`-. .-'

Q_π⁺ = Q_u + Q_d̅ = (+2∕3 e) + (−(−1∕3 e)) = +1 e.


π⁻ ≡ u̅d

. ' ' .
' (−) '
: :
. (−) ,
`-. .-'

Q_π⁻ = Q_u̅ + Q_d = −(+2∕3 e) + (−1∕3 e)) = −1 e.


π⁰ ≡ uu̅

. ' ' .
' (−) '
: :
. (+) ,
`-. .-'

Q_π⁰ = Q_u + Q_u̅ = (+2∕3 e) + (−(+2∕3 e)) = 0 e.


π⁰ ≡ dd̅

. ' ' .
' (+) '
: :
. (−) , __
`-. .-' |PE

Q_π⁰ = Q_d + Q_d̅ = (−1∕3 e) + (−(−1∕3 e)) = 0 e.
I suggest that the 3 orthogonal dimensions enforce that jet shape
Not even wrong.
and the evidence is new! The cube at the center of iron is
the realistic shape of a static nucleus. The Simple Cubic
core of the elements is evidence of the strict 3D basis
that made those 3 jets of hadrons.
I don't have any reason to think
that the atomic nucleus isn't
billiard ball or plum pudding.
There are scattering experiments by Rutherford et al. that *show* it is neither.

<https://en.wikipedia.org/wiki/Proton#History>
<https://en.wikipedia.org/wiki/Quark#History>

X-Post & F’up2 sci.physics.particle
--
PointedEars

Twitter: @PointedEars2
Please do not cc me. / Bitte keine Kopien per E-Mail.
Tom Roberts
2018-06-29 03:18:53 UTC
Permalink
Post by Thomas 'PointedEars' Lahn
Quark experimental basis was 3 jets of hadrons.
Only in the broadest possible sense.
Not really, in ANY sense.

3-jet events were not observed until well after QCD and the standard
model were formulated. Basically it takes high energy to be able to
identify jets as jets [#], and this pretty much had to wait for LEP and
the Tevatron -- at lower energies the particles of different "jets"
overlap too much. The kicker is that 3-jet events were seen first in
e+e- collisions, in which there are no quarks in the initial state --
since quarks can only be created in pairs, having THREE jets is evidence
for GLUONS, not quarks.

[#] in the sense of being an initial quark exiting a
pointlike high-energy interaction that became "dressed"
into a bunch of nearly co-moving hadrons.

The original motivation for quarks was the observed patterns in meson
and baryon masses, spins, parities, and decays. This was long before QCD
and the standard model, but became the basis for them.
Post by Thomas 'PointedEars' Lahn
I suggest that the 3 orthogonal dimensions enforce that jet shape
Not even wrong.
Right -- that is not even wrong. Here there are THREE coincidences that
involve the number 3:
a. we see 3 spatial dimensions
b. baryons have 3 valence quarks [@]
c. there are 3-jet events
As far as we know today, there are indeed COINCIDENCES:
For (a) -- what about the 4th dimension of time?
For (b) -- what about mesons with 2 quarks?
For (c) -- what about 2-jet and 4-jet events?

[@] Baryons have LOTS more inside than just 3 quarks.
For instance, the proton has a mass of ~ 938 MeV, but
the rest masses of its three valence quarks sum up to
about 9 MeV (!) -- there is A LOT more going on in there!
Post by Thomas 'PointedEars' Lahn
I don't have any reason to think
that the atomic nucleus isn't
billiard ball or plum pudding.
There are scattering experiments by Rutherford et al. that *show* it is neither.
<https://en.wikipedia.org/wiki/Proton#History>
<https://en.wikipedia.org/wiki/Quark#History>
Plus all the evidence supporting the standard model, which is
essentially every one of the many thousands of particle experiment ever
performed.

Tom Roberts
r***@gmail.com
2018-06-29 20:46:55 UTC
Permalink
Post by Tom Roberts
Post by Thomas 'PointedEars' Lahn
Quark experimental basis was 3 jets of hadrons.
Only in the broadest possible sense.
Not really, in ANY sense.
3-jet events were not observed until well after QCD and the standard
model were formulated. Basically it takes high energy to be able to
identify jets as jets [#], and this pretty much had to wait for LEP and
the Tevatron -- at lower energies the particles of different "jets"
overlap too much. The kicker is that 3-jet events were seen first in
e+e- collisions, in which there are no quarks in the initial state --
since quarks can only be created in pairs, having THREE jets is evidence
for GLUONS, not quarks.
[#] in the sense of being an initial quark exiting a
pointlike high-energy interaction that became "dressed"
into a bunch of nearly co-moving hadrons.
The original motivation for quarks was the observed patterns in meson
and baryon masses, spins, parities, and decays. This was long before QCD
and the standard model, but became the basis for them.
Post by Thomas 'PointedEars' Lahn
I suggest that the 3 orthogonal dimensions enforce that jet shape
Not even wrong.
Right -- that is not even wrong. Here there are THREE coincidences that
a. we see 3 spatial dimensions
c. there are 3-jet events
For (a) -- what about the 4th dimension of time?
For (b) -- what about mesons with 2 quarks?
For (c) -- what about 2-jet and 4-jet events?
For instance, the proton has a mass of ~ 938 MeV, but
the rest masses of its three valence quarks sum up to
about 9 MeV (!) -- there is A LOT more going on in there!
Post by Thomas 'PointedEars' Lahn
I don't have any reason to think
that the atomic nucleus isn't
billiard ball or plum pudding.
There are scattering experiments by Rutherford et al. that *show* it is neither.
<https://en.wikipedia.org/wiki/Proton#History>
<https://en.wikipedia.org/wiki/Quark#History>
Plus all the evidence supporting the standard model, which is
essentially every one of the many thousands of particle experiment ever
performed.
Tom Roberts
Thanks, I quite mostly agree, and there was follow-up
back in sci.physics.relativity, where this broken
"Google Groups" usenet browser doesn't know it.

("Plum pudding" was wrong because that's
an atomic model of electrons and protons,
not a nuclear model of protons and neutrons.)

Tom Roberts
2018-06-29 05:07:19 UTC
Permalink
Post by Thomas 'PointedEars' Lahn
Quark experimental basis was 3 jets of hadrons.
Only in the broadest possible sense.
Not really, in ANY sense.

3-jet events were not observed until well after QCD and the standard
model were formulated. Basically it takes high energy to be able to
identify jets as jets [#], and this pretty much had to wait for LEP and
the Tevatron -- at lower energies the particles of different "jets"
overlap too much. The kicker is that 3-jet events were seen first in
e+e- collisions, in which there are no quarks in the initial state --
since quarks can only be created in pairs, having THREE jets is evidence
for GLUONS, not quarks.

[#] in the sense of being an initial quark exiting a
pointlike high-energy interaction that became "dressed"
into a bunch of nearly co-moving hadrons.

The original motivation for quarks was the observed patterns in meson
and baryon masses, spins, parities, and decays. This was long before QCD
and the standard model, but became the basis for them.
Post by Thomas 'PointedEars' Lahn
I suggest that the 3 orthogonal dimensions enforce that jet shape
Not even wrong.
Right -- that is not even wrong. Here there are THREE coincidences that
involve the number 3:
a. we see 3 spatial dimensions
b. baryons have 3 valence quarks [@]
c. there are 3-jet events
As far as we know today, there are indeed COINCIDENCES:
For (a) -- what about the 4th dimension of time?
For (b) -- what about mesons with 2 quarks?
For (c) -- what about 2-jet and 4-jet events?

[@] Baryons have LOTS more inside than just 3 quarks.
For instance, the proton has a mass of ~ 938 MeV, but
the rest masses of its three valence quarks sum up to
about 9 MeV (!) -- there is A LOT more going on in there!
Post by Thomas 'PointedEars' Lahn
I don't have any reason to think
that the atomic nucleus isn't
billiard ball or plum pudding.
There are scattering experiments by Rutherford et al. that *show* it is neither.
<https://en.wikipedia.org/wiki/Proton#History>
<https://en.wikipedia.org/wiki/Quark#History>
Plus all the evidence supporting the standard model, which is
essentially every one of the many thousands of particle experiment ever
performed.

Tom Roberts
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