In article <sch6j1$vff$1@dont-email.me>, Indy Jess John
<bathwatchdog@OMITTHISgooglemail.com> wrote:
> Not quite. The cannon ball has a greater mass than a feather. Therefore
> the Newton theory indicates that the mutual attraction of two bodies,
> and given that the earth is the constant on one side, the greater mass
> of the cannon ball should mean it reaches the ground a fraction sooner
> than the lower mass of a feather. When an experiment to demonstrate what
> actually happens in a vacuum did not show that theoretical difference
> in time, it reduced Newton's Law to the status of best guess.

The attraction increases. But so does the intertial mass. The two factors
essentially cancel.

Or is your point that the *Earth* moves further?

Again, I can't recall this being said in the programme.

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics https://www.st-andrews.ac.uk/~www_pa/Scots_Guide/intro/electron.htm
biog http://jcgl.orpheusweb.co.uk/history/ups_and_downs.html
Audio Misc http://www.audiomisc.co.uk/index.html

In article <un8oegdhs82jo7brkf9vkf94ngamqc1rd4@4ax.com>, Roderick Stewart
<rjfs@escapetime.myzen.co.uk> wrote:

> Curved space must have consistent rules too, complicated ones I'm sure,
> but consistent within its own terms.

> Defining things in flat space (as we do for pi for example) and then
> curving it afterwards and declaring the definitions to be therefore
> untrue is just cheating by moving the goalposts.

The Universe doesn't care about what we think is 'cheating'. It just
returns a different diameter/circumference ratio depending on the local GR
details. :-)

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics https://www.st-andrews.ac.uk/~www_pa/Scots_Guide/intro/electron.htm
biog http://jcgl.orpheusweb.co.uk/history/ups_and_downs.html
Audio Misc http://www.audiomisc.co.uk/index.html

In article <fb9oeg12itvnbcgi8herphha0f0d9c015k@4ax.com>, Roderick Stewart
<rjfs@escapetime.myzen.co.uk> wrote:
> Maybe I'm not making myself clear. If you draw a circle on a ball in
> order to measure the value of pi, you're not drawing it on a flat
> surface. The value of pi is *defined* on a flat surface.

By "is" you mean that this is what you and many textbooks assume.

However mere reality may not have read those books, and innocently does
otherwise. :-)

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics https://www.st-andrews.ac.uk/~www_pa/Scots_Guide/intro/electron.htm
biog http://jcgl.orpheusweb.co.uk/history/ups_and_downs.html
Audio Misc http://www.audiomisc.co.uk/index.html

In article <f8qoegtfjh5qjab754s795nfiss67qvu3k@4ax.com>, BrightsideS9
<reply_to_address_is_not@invalid.invalid> wrote:

> I am keeping up. C/R =pi is reality in Eclidean geometry (one of many
> geometries) You cleverly (or so you thought) used non euclidean geometry
> to try to disprrove the C/R = pi. And then a sweeping statement that
> geometry isn't as constant as someone believes. What geomertry isn't
> constant? Eluidate. Name the geometry. I am an eager student.

Define what you mean by "geometry". :-)

Will General Relativity do? It is usually defined in terms of 4D geometric
form. And can be used to specify how the measured value of pi will vary in
accord with local mass/etc distributions, etc.

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics https://www.st-andrews.ac.uk/~www_pa/Scots_Guide/intro/electron.htm
biog http://jcgl.orpheusweb.co.uk/history/ups_and_downs.html
Audio Misc http://www.audiomisc.co.uk/index.html

On Wed, 14 Jul 2021 10:18:52 +0100
Jim Lesurf <noise@audiomisc.co.uk> wrote:
>In article <mg2oeglrdsapvpki52kgnk6cmpida9rutf@4ax.com>, Roderick Stewart
><rjfs@escapetime.myzen.co.uk> wrote:
>
>> The circumference of planet Zog on the other side of the universe
>> divided by its diameter will be the same value as any equivalent
>> measurement of any circle anywhere in existence, regardless of the
>> number system in which you express it, or the number of fingers the
>> inhabitants of planet Zog may have.
>
>That is incorrect. General Relativity tells us that the geometry of
>space-time alters with the distribution of mass/energy/stress. The standard
>definition of pi assumes a 'flat' space. Which in general is just a good
>approximation.

Thats already been explained to him. He didn't get it.

On Wed, 14 Jul 2021 10:35:53 +0100, Jim Lesurf <noise@audiomisc.co.uk>
wrote:

>In article <f8qoegtfjh5qjab754s795nfiss67qvu3k@4ax.com>, BrightsideS9
><reply_to_address_is_not@invalid.invalid> wrote:
>
>> I am keeping up. C/R =pi is reality in Eclidean geometry (one of many
>> geometries) You cleverly (or so you thought) used non euclidean geometry
>> to try to disprrove the C/R = pi. And then a sweeping statement that
>> geometry isn't as constant as someone believes. What geomertry isn't
>> constant? Eluidate. Name the geometry. I am an eager student.
>
>Define what you mean by "geometry". :-)

What part of the expression Euclidean Geometry is not understood. Oh!
Did the typo confuse you. ;-)

Euclidean Geometry - the geometric properties of objects that exist in
a flat two-dimensional plane.

--
brightside S9

On Thu, 15 Jul 2021 10:09:10 +0100
BrightsideS9 <reply_to_address_is_not@invalid.invalid> wrote:
>On Wed, 14 Jul 2021 10:35:53 +0100, Jim Lesurf <noise@audiomisc.co.uk>
>wrote:
>
>>In article <f8qoegtfjh5qjab754s795nfiss67qvu3k@4ax.com>, BrightsideS9
>><reply_to_address_is_not@invalid.invalid> wrote:
>>
>>> I am keeping up. C/R =pi is reality in Eclidean geometry (one of many
>>> geometries) You cleverly (or so you thought) used non euclidean geometry
>>> to try to disprrove the C/R = pi. And then a sweeping statement that
>>> geometry isn't as constant as someone believes. What geomertry isn't
>>> constant? Eluidate. Name the geometry. I am an eager student.
>>
>>Define what you mean by "geometry". :-)
>
>What part of the expression Euclidean Geometry is not understood. Oh!
>Did the typo confuse you. ;-)
>
>Euclidean Geometry - the geometric properties of objects that exist in
>a flat two-dimensional plane.

The discussion was about the nature of reality and the jury is still out
on whether space is flat.

On Wed, 14 Jul 2021 10:30:16 +0100, Jim Lesurf <noise@audiomisc.co.uk>
wrote:

>In article <fb9oeg12itvnbcgi8herphha0f0d9c015k@4ax.com>, Roderick Stewart
><rjfs@escapetime.myzen.co.uk> wrote:
>> Maybe I'm not making myself clear. If you draw a circle on a ball in
>> order to measure the value of pi, you're not drawing it on a flat
>> surface. The value of pi is *defined* on a flat surface.
>
>By "is" you mean that this is what you and many textbooks assume.

I mean that as far as I know it's the universally agreed definition.
The textbooks don't "assume" it; they tell us what it is; it can be
worked out.

The ratio of circumference to diameter may be different on a curved
surface, but it's not pi, it's some other number depending on the type
and degree of curvature. If you prefer, you could regard pi as a
special case of a wider definition that just happens to have a
particular value when the curvature of the surface is zero, but
whatever words you use to describe the stuation, the numerical value
you end up with is fixed and not the result of anybody's decision. Any
intelligent lifeform anywhere in the universe that worked it out from
first principles (which is possible without reference to anything in
physical reality, because it doesn't depend on physical reality, it's
a pure abstract idea) would arrive at exactly the same value.

Thus pi, like every other mathematical truth, relationship or value,
is an example of something which could not have been "created" in the
sense of somebody (or something) deciding how it should be. It may be
made to look different depending on the language or notaion you
choose, but its numerical value cannot be anything other than what it
is, and even a god could not change it.

Rod.

On Wed, 14 Jul 2021 10:25:03 +0100, Jim Lesurf <noise@audiomisc.co.uk>
wrote:

>In article <sch6j1$vff$1@dont-email.me>, Indy Jess John
><bathwatchdog@OMITTHISgooglemail.com> wrote:
>> Not quite. The cannon ball has a greater mass than a feather. Therefore
>> the Newton theory indicates that the mutual attraction of two bodies,
>> and given that the earth is the constant on one side, the greater mass
>> of the cannon ball should mean it reaches the ground a fraction sooner
>> than the lower mass of a feather. When an experiment to demonstrate what
>> actually happens in a vacuum did not show that theoretical difference
>> in time, it reduced Newton's Law to the status of best guess.
>
>The attraction increases. But so does the intertial mass. The two factors
>essentially cancel.
>
>Or is your point that the *Earth* moves further?
>
>Again, I can't recall this being said in the programme.
>
>Jim

Perhaps if you were being super extra pedantic, you might argue that
if you dropped a cannon ball and a feather side by side at the same
time, the extra mass of the cannon ball would move the Earth closer to
both of them, and thus shorten the time for the feather to hit it,
from the time it would have taken if the feather had been dropped on
its own. I doubt if you'd be able to measure the effect in reality,
but it's just a thought experiment, isn't it?

Rod.

On 14/07/2021 10:18, Jim Lesurf wrote:
> In article <mg2oeglrdsapvpki52kgnk6cmpida9rutf@4ax.com>, Roderick Stewart
> <rjfs@escapetime.myzen.co.uk> wrote:
>
>> The circumference of planet Zog on the other side of the universe
>> divided by its diameter will be the same value as any equivalent
>> measurement of any circle anywhere in existence, regardless of the
>> number system in which you express it, or the number of fingers the
>> inhabitants of planet Zog may have.
>
> That is incorrect. General Relativity tells us that the geometry of
> space-time alters with the distribution of mass/energy/stress. The standard
> definition of pi assumes a 'flat' space. Which in general is just a good
> approximation.

Not so much a flat spce, but taken in the plane of the circle, so even
when the circle is drawn on a ball, the plane of the circle through
the ball defines PI.

On 15/07/2021 11:09, Roderick Stewart wrote:
> On Wed, 14 Jul 2021 10:30:16 +0100, Jim Lesurf <noise@audiomisc.co.uk>
> wrote:
>
>> In article <fb9oeg12itvnbcgi8herphha0f0d9c015k@4ax.com>, Roderick Stewart
>> <rjfs@escapetime.myzen.co.uk> wrote:
>>> Maybe I'm not making myself clear. If you draw a circle on a ball in
>>> order to measure the value of pi, you're not drawing it on a flat
>>> surface. The value of pi is *defined* on a flat surface.
>>
>> By "is" you mean that this is what you and many textbooks assume.
>
> I mean that as far as I know it's the universally agreed definition.
> The textbooks don't "assume" it; they tell us what it is; it can be
> worked out.
>
> The ratio of circumference to diameter may be different on a curved
> surface, but it's not pi, it's some other number depending on the type
> and degree of curvature.

Irrespectiive of the nature of the curvature of the surface, if all
parts of what you draw are not coplanar, then what you haven't got
is a circle!

eg, were you to have a circle drawn on a flat piece of paper, and then
that paper were to be wrapped around some other curved object, then
the resultant shape will have some other geometric definition other
than a circle.

On 15/07/2021 01:07, Bill Findlay wrote:
> On 15 Jul 2021, williamwright wrote
> (in article <il9c7cF8oe3U2@mid.individual.net>):
>
>> On 14/07/2021 23:53, Bill Findlay wrote:
>>> On 14 Jul 2021, gareth evans wrote
>>> (in article <scmjf7$n74$1@dont-email.me>):
>>>
>>>> On 14/07/2021 01:24, Bill Findlay wrote:
>>>>>
>>>>> Homophobes do seem to have a bit of a shit fixation.
>>>>
>>>> ... as do male homosexuals?
>>>
>>> No.
>> Why should they have?
>
> It seems we have flushed out another homophobe.
>

To know that some behaviours are abnormal does not
make one hating nor fearing.

"gareth evans" <headstone255@yahoo.com> wrote in message
news:scp2ca$vp9$1@dont-email.me...
> Irrespectiive of the nature of the curvature of the surface, if all
> parts of what you draw are not coplanar, then what you haven't got
> is a circle!
>
> eg, were you to have a circle drawn on a flat piece of paper, and then
> that paper were to be wrapped around some other curved object, then
> the resultant shape will have some other geometric definition other
> than a circle.

What's the geometric definition of wrinkles and creases? ;-)

On Thu, 15 Jul 2021 09:11:27 +0000 (UTC),
MrSpud_1_c@nv4til6krizewk.biz wrote:

>On Thu, 15 Jul 2021 10:09:10 +0100
>BrightsideS9 <reply_to_address_is_not@invalid.invalid> wrote:
>>On Wed, 14 Jul 2021 10:35:53 +0100, Jim Lesurf <noise@audiomisc.co.uk>
>>wrote:
>>
>>>In article <f8qoegtfjh5qjab754s795nfiss67qvu3k@4ax.com>, BrightsideS9
>>><reply_to_address_is_not@invalid.invalid> wrote:
>>>
>>>> I am keeping up. C/R =pi is reality in Eclidean geometry (one of many
>>>> geometries) You cleverly (or so you thought) used non euclidean geometry
>>>> to try to disprrove the C/R = pi. And then a sweeping statement that
>>>> geometry isn't as constant as someone believes. What geomertry isn't
>>>> constant? Eluidate. Name the geometry. I am an eager student.
>>>
>>>Define what you mean by "geometry". :-)
>>
>>What part of the expression Euclidean Geometry is not understood. Oh!
>>Did the typo confuse you. ;-)
>>
>>Euclidean Geometry - the geometric properties of objects that exist in
>>a flat two-dimensional plane.
>
>The discussion was about the nature of reality and the jury is still out
>on whether space is flat.
>

It's possible to derive the value of pi (not by me but by somebody
clever enough) without reference to geometry at all. The same can be
said of a great many other mathematical properties and relationships,
because they can exist in pure thoughtspace and so are unaffected by
any aspect of physical reality.

But we can observe that the dependency often does apply the other way
round. Many aspects of physical reality, such as the inverse square
law, maximum packing densities of various shapes, and many others, are
affected by mathematical relationships, and this leads me to speculate
that maybe they all are. Maybe the whole of reality is dependent on
mathematical truth, and if anybody ever does find a Grand Unified
Theory of Everything, that's what it will have to be based on.

Rod.

On Thu, 15 Jul 2021 12:03:21 +0100
Roderick Stewart <rjfs@escapetime.myzen.co.uk> wrote:
>But we can observe that the dependency often does apply the other way
>round. Many aspects of physical reality, such as the inverse square
>law, maximum packing densities of various shapes, and many others, are
>affected by mathematical relationships, and this leads me to speculate
>that maybe they all are. Maybe the whole of reality is dependent on

Maths intersects with aspects of reality, but there are some aspects of
mathematics that do not exist in the real world , eg various types of
infinity. Also mathametics cannot describe reality accuractly as witnessed
by pi being an irrational number.

Jim Lesurf <noise@audiomisc.co.uk> wrote:
> Will General Relativity do? It is usually defined in terms of 4D geometric
> form. And can be used to specify how the measured value of pi will vary in
> accord with local mass/etc distributions, etc.

An important point here is that any "measured value of pi" is *not*
the value of the mathematical constant pi, because the value of the
mathematical constant is defined mathematically.

Also, in any region of constant curvature, the "measured value of pi"
will depend on the size of the circle used; e.g. for fixed curvature,
as a circle shrinks, the flatter the space appears, and so that circle,
if ideally measured, will produce a measured value of pi ever closer
to the mathematically defined value.

#Paul

On 15/07/2021 12:03, Roderick Stewart wrote:
>>
>
> It's possible to derive the value of pi (not by me but by somebody
> clever enough) without reference to geometry at all.

ISTR 4*ARCTAN(1)

.... and hopefully the series expansion for ARCTAN does not
depend on an initial use of PI else it would be
Post Hoc Ergo Propter Hoc

On 15 Jul 2021, gareth evans wrote
(in article <scp2f6$vp9$2@dont-email.me>):

> On 15/07/2021 01:07, Bill Findlay wrote:
> > On 15 Jul 2021, williamwright wrote
> > (in article <il9c7cF8oe3U2@mid.individual.net>):
> >
> > > On 14/07/2021 23:53, Bill Findlay wrote:
> > > > On 14 Jul 2021, gareth evans wrote
> > > > (in article <scmjf7$n74$1@dont-email.me>):
> > > >
> > > > > On 14/07/2021 01:24, Bill Findlay wrote:
> > > > > >
> > > > > > Homophobes do seem to have a bit of a shit fixation.
> > > > >
> > > > > ... as do male homosexuals?
> > > >
> > > > No.
> > > Why should they have?
> >
> > It seems we have flushed out another homophobe.
>
> To know that some behaviours are abnormal does not
> make one hating nor fearing.

That is why I neither hate nor fear you.

--
Bill Findlay

On 15/07/2021 19:01, Bill Findlay wrote:
> On 15 Jul 2021, gareth evans wrote
> (in article <scp2f6$vp9$2@dont-email.me>):
>
>> On 15/07/2021 01:07, Bill Findlay wrote:
>>> On 15 Jul 2021, williamwright wrote
>>> (in article <il9c7cF8oe3U2@mid.individual.net>):
>>>
>>>> On 14/07/2021 23:53, Bill Findlay wrote:
>>>>> On 14 Jul 2021, gareth evans wrote
>>>>> (in article <scmjf7$n74$1@dont-email.me>):
>>>>>
>>>>>> On 14/07/2021 01:24, Bill Findlay wrote:
>>>>>>>
>>>>>>> Homophobes do seem to have a bit of a shit fixation.
>>>>>>
>>>>>> ... as do male homosexuals?
>>>>>
>>>>> No.
>>>> Why should they have?
>>>
>>> It seems we have flushed out another homophobe.
>>
>> To know that some behaviours are abnormal does not
>> make one hating nor fearing.
>
> That is why I neither hate nor fear you.
>

You seem determined to be rude

On 15 Jul 2021, gareth evans wrote
(in article <scq3mc$7jj$1@dont-email.me>):

> On 15/07/2021 19:01, Bill Findlay wrote:
> > On 15 Jul 2021, gareth evans wrote
> > (in article <scp2f6$vp9$2@dont-email.me>):
> >
> > > On 15/07/2021 01:07, Bill Findlay wrote:
> > > > On 15 Jul 2021, williamwright wrote
> > > > (in article <il9c7cF8oe3U2@mid.individual.net>):
> > > >
> > > > > On 14/07/2021 23:53, Bill Findlay wrote:
> > > > > > On 14 Jul 2021, gareth evans wrote
> > > > > > (in article <scmjf7$n74$1@dont-email.me>):
> > > > > >
> > > > > > > On 14/07/2021 01:24, Bill Findlay wrote:
> > > > > > > >
> > > > > > > > Homophobes do seem to have a bit of a shit fixation.
> > > > > > >
> > > > > > > ... as do male homosexuals?
> > > > > >
> > > > > > No.
> > > > > Why should they have?
> > > >
> > > > It seems we have flushed out another homophobe.
> > >
> > > To know that some behaviours are abnormal does not
> > > make one hating nor fearing.
> >
> > That is why I neither hate nor fear you.
>
> You seem determined to be rude

What a deeply silly and unreflective accusation.
Your "I'm the gentleman here" act impresses no one.

--
Bill Findlay

On 15/07/2021 21:06, Bill Findlay wrote:
> On 15 Jul 2021, gareth evans wrote
> (in article <scq3mc$7jj$1@dont-email.me>):
>
>> On 15/07/2021 19:01, Bill Findlay wrote:
>>> On 15 Jul 2021, gareth evans wrote
>>> (in article <scp2f6$vp9$2@dont-email.me>):
>>>
>>>> On 15/07/2021 01:07, Bill Findlay wrote:
>>>>> On 15 Jul 2021, williamwright wrote
>>>>> (in article <il9c7cF8oe3U2@mid.individual.net>):
>>>>>
>>>>>> On 14/07/2021 23:53, Bill Findlay wrote:
>>>>>>> On 14 Jul 2021, gareth evans wrote
>>>>>>> (in article <scmjf7$n74$1@dont-email.me>):
>>>>>>>
>>>>>>>> On 14/07/2021 01:24, Bill Findlay wrote:
>>>>>>>>>
>>>>>>>>> Homophobes do seem to have a bit of a shit fixation.
>>>>>>>>
>>>>>>>> ... as do male homosexuals?
>>>>>>>
>>>>>>> No.
>>>>>> Why should they have?
>>>>>
>>>>> It seems we have flushed out another homophobe.
>>>>
>>>> To know that some behaviours are abnormal does not
>>>> make one hating nor fearing.
>>>
>>> That is why I neither hate nor fear you.
>>
>> You seem determined to be rude
>
> What a deeply silly and unreflective accusation.
> Your "I'm the gentleman here" act impresses no one.
>

You still seem determined to be rude.

On 15/07/2021 01:07, Bill Findlay wrote:
> On 15 Jul 2021, williamwright wrote
> (in article <il9c7cF8oe3U2@mid.individual.net>):
>
>> On 14/07/2021 23:53, Bill Findlay wrote:
>>> On 14 Jul 2021, gareth evans wrote
>>> (in article <scmjf7$n74$1@dont-email.me>):
>>>
>>>> On 14/07/2021 01:24, Bill Findlay wrote:
>>>>>
>>>>> Homophobes do seem to have a bit of a shit fixation.
>>>>
>>>> ... as do male homosexuals?
>>>
>>> No.
>> Why should they have?
>
> It seems we have flushed out another homophobe.
>
The fact that this sort of topic interests a surprisingly large number
of men makes me wonder if a lot of people are not completely at ease
with all aspects of their sexuality.

Bill

On 15/07/2021 11:25, gareth evans wrote:

>>
>> It seems we have flushed out another homophobe.
>>
>
> To know that some behaviours are abnormal does not
> make one hating nor fearing.

'phobe' is a silly suffix.

Bill

On Thu, 15 Jul 2021 12:03:21 +0100, Roderick Stewart
<rjfs@escapetime.myzen.co.uk> wrote in
<qg40fglmuueuovoh3hsq69njpble39sr0s@4ax.com>:

>It's possible to derive the value of pi (not by me but by somebody
>clever enough) without reference to geometry at all. The same can be
>said of a great many other mathematical properties and relationships,
>because they can exist in pure thoughtspace and so are unaffected by
>any aspect of physical reality.

Euler's formula - e^(i*pi) = -1 - is an example that relates three of
the important numbers in mathematics. From what I remember, there is no
geometry involved in that.

On Thu, 15 Jul 2021 11:31:16 +0000 (UTC),
MrSpud__6_Empu@_wcx8qng2806nrkb65.co.uk wrote in
<scp6a4$ns5$1@gioia.aioe.org>:

>Also mathametics cannot describe reality accuractly as witnessed
>by pi being an irrational number.

Pi is transcendental rather than just irrational (this has been known
since the 19th Century). There are whole branches of mathematics that
deal with things that cannot be expressed in the number system we use in
normal life. The difficulty in describing reality is not a weakness in
mathematics.