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What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<

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  What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Keith Stein <keithstein111@gmail.com> - 2018-11-15 17:17 +0000
    Re:What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com> - 2018-11-15 19:54 +0100
      Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-11-15 20:32 +0100
        Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< mlwozniak@wp.pl - 2018-11-15 12:04 -0800
        Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Shon Wible <shwn@shouve.wd> - 2018-11-16 20:22 +0000
        Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Sergio <invalid@invalid.com> - 2018-11-19 17:26 -0600
          Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Lochù Umská <lare@cpi2alwa.cc> - 2018-11-19 23:35 +0000
            Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Sergio <invalid@invalid.com> - 2018-11-19 22:05 -0600
              Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Elden Lathan <an@tnettw.ea> - 2018-11-22 19:25 +0000
          Gravitational waves (was: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-11-20 03:11 +0100
            Re: Gravitational waves (was: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<) Sergio <invalid@invalid.com> - 2018-11-19 22:23 -0600
              Re: Gravitational waves Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-11-20 09:08 +0100
          Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Tom Roberts <tjroberts137@sbcglobal.net> - 2018-11-19 22:23 -0600
          Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< benj <benj.fake@gmail.com> - 2018-11-20 11:46 -0500
            Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-11-20 21:26 +0100
              Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< benj <benj.fake@gmail.com> - 2018-11-20 19:43 -0500
                Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-11-21 02:18 +0100
            Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Tom Roberts <tjroberts137@sbcglobal.net> - 2018-11-20 15:51 -0600
              Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Paul Edgar <lara@uldewan.lg> - 2018-11-21 18:12 +0000
                Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Sergio <invalid@invalid.com> - 2018-11-21 13:43 -0600
          Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< JanPB <filmart@gmail.com> - 2018-11-20 14:06 -0800
            Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Tom Roberts <tjroberts137@sbcglobal.net> - 2018-11-20 19:55 -0600
              Re: What Every Physicist Needs to Know Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-11-21 03:02 +0100
              Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< JanPB <filmart@gmail.com> - 2018-11-20 19:21 -0800
                Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Gary Harnagel <hitlong@yahoo.com> - 2018-11-20 19:44 -0800
                  Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Tom Roberts <tjroberts137@sbcglobal.net> - 2018-11-21 12:20 -0600
                    Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< JanPB <filmart@gmail.com> - 2018-11-21 17:20 -0800
      Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Keith Stein <keithstein111@gmail.com> - 2018-11-15 20:54 +0000
        Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< mlwozniak@wp.pl - 2018-11-15 13:07 -0800
          Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Keith Stein <keithstein111@gmail.com> - 2018-11-16 02:07 +0000
            Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-11-16 03:25 +0100
              Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Keith Stein <keithstein111@gmail.com> - 2018-11-16 13:34 +0000
                Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-11-16 19:50 +0100
                  Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Keith Stein <keithstein111@gmail.com> - 2018-11-16 20:46 +0000
                    Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-11-16 22:36 +0100
                      Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Keith Stein <keithstein111@gmail.com> - 2018-11-16 22:10 +0000
                        Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-11-16 23:25 +0100
                          Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Keith Stein <keithstein111@gmail.com> - 2018-11-17 02:44 +0000
                            Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-11-17 18:39 +0100
                            Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Shon Wible <shwp@swouve.we> - 2018-11-17 19:21 +0000
                              Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-11-18 15:29 +0100
                                Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Isidro Vitti <itri@ovwdiwi.ot> - 2018-11-18 17:04 +0000
                                  Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-11-18 19:31 +0100
            Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< mlwozniak@wp.pl - 2018-11-15 23:03 -0800
              Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Keith Stein <keithstein111@gmail.com> - 2018-11-16 13:53 +0000
                Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< mlwozniak@wp.pl - 2018-11-16 09:31 -0800
                  Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Keith Stein <keithstein111@gmail.com> - 2018-11-19 22:34 +0000
                    Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< JanPB <filmart@gmail.com> - 2018-11-19 15:02 -0800
        Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Sergio <invalid@invalid.com> - 2018-11-19 21:57 -0600
          Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-11-20 09:16 +0100
            Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< moroney@world.std.spaamtrap.com (Michael Moroney) - 2018-11-20 17:48 +0000
          Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Keith Stein <keithstein111@gmail.com> - 2018-11-20 12:47 +0000
          Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Sergio <invalid@invalid.com> - 2018-11-20 10:01 -0600
          Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< JanPB <filmart@gmail.com> - 2018-11-20 14:14 -0800
    Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< numbernumber1964@gmail.com - 2018-11-19 10:16 -0800
    Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< numbernumber1964@gmail.com - 2018-11-20 15:55 -0800
    Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< numbernumber1964@gmail.com - 2018-11-20 15:59 -0800
    Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< numbernumber1964@gmail.com - 2018-11-21 12:20 -0800

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#477649

On Monday, November 19, 2018 at 3:26:09 PM UTC-8, Sergio wrote:
> On 11/15/2018 1:32 PM, Thomas 'PointedEars' Lahn wrote:
> > Libor Striz wrote on 15.11.18 19:54:
> >> Keith Stein <keithstein111@gmail.com> Wrote in message:
> >>> How to Program a Computer eh!
> >>
> >> They have programmers for that.
> > 
> > Speaking as a professional software developer, it is seldom efficient to
> > employ a professional software developer (the term “programmer” as a job
> > description went out of fashion some 30 years ago, and rightly so) for this
> > because you have to understand the physics, too.
> 
> true
> 
> > 
> > This is why learning to use computers for solving physics problems is a part
> > of the undergraduate physics curriculum.  So, for a change, Keith Stein is
> > (probably accidentally) correct this time.
> 
> in the old days, you had to do the calculations/equations by hand, now
> they are in libraries like Java libraries on your computer, and they are
> well tested.

Ugh, Java. Always hated the stuff. For any GUI programming work Qt in C++
is much better, and for mathematical libraries you have C++ template (NOT
binary!) libraries like Eigen or Boost, they work fantastic: speed,
reliability, and superior debugging using them since they are all
explicit source code, so you can step through it if necessary, and even
change it (used to happen in the early days of Qt, extremely
convenient). Last but not least, Java floating-point engine has
problems which AFAIK have never been fixed, despite being pointed
out 20(!) years ago by William Kahan: 
https://people.eecs.berkeley.edu/~wkahan/JAVAhurt.pdf 

If they have in fact been fixed, let me know.

--
Jan

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#477685

On 11/20/18 4:06 PM, JanPB wrote:
> [... programming languages]

I am both physicist and professional software developer. To me, the 
choice of programming language is secondary -- I always choose libraries 
that support what I am doing [#]; I can learn a new programming language 
in a day or two. So for particle simulations, I use C++ because of the 
Geant4 and CLHEP toolkits. For simple analyses and plotting, I use 
Python because of numpy, scipy, and matplotlib. For GUIs, C++/Qt and 
Python/tkinter are quite different but I use both, depending on what 
they are interfacing to.

	[#] Choice of programming language affects productivity
	at the 10% level; choice of libraries affects it by
	factors of 10 to 1000 or more. Geant4 makes possible
	programs that would be utterly infeasible without it (due
	to the _physics_ that went into it).

I have in the past used FORTRAN, but it has been completely replaced by 
C++. I have also used Java, but it has now been replaced by Python.

	By "use" I mean I have written > 50,000 lines of code,
	so I am (or was) expert. I have written less code in Ruby,
	SNOBOL, BASIC, ALGOL, lisp, HTML+Javascript+PHP, bash, and
	assembly languages of nearly a dozen CPUs. Unusually, I have
	written or been the primary architect and developer of three
	different real-time OS kernels (Z80, BELLMAC-8, PowerPC).

I anticipate looking into machine-learning and AI toolkits....

Tom Roberts

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#477686 — Re: What Every Physicist Needs to Know

Tom Roberts wrote:
> I anticipate looking into machine-learning and AI toolkits....

Good idea.  For example, Dr. Barish also mentioned that it will be important
for GW research to combine machine learning with statistics.

-- 
PointedEars

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

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#477689

On Tuesday, November 20, 2018 at 5:55:29 PM UTC-8, tjrob137 wrote:
> On 11/20/18 4:06 PM, JanPB wrote:
> > [... programming languages]
> 
> I am both physicist and professional software developer. To me, the 
> choice of programming language is secondary -- I always choose libraries 
> that support what I am doing [#]; I can learn a new programming language 
> in a day or two. So for particle simulations, I use C++ because of the 
> Geant4 and CLHEP toolkits. For simple analyses and plotting, I use 
> Python because of numpy, scipy, and matplotlib. For GUIs, C++/Qt and 
> Python/tkinter are quite different but I use both, depending on what 
> they are interfacing to.
> 
> 	[#] Choice of programming language affects productivity
> 	at the 10% level; choice of libraries affects it by
> 	factors of 10 to 1000 or more. Geant4 makes possible
> 	programs that would be utterly infeasible without it (due
> 	to the _physics_ that went into it).
> 
> I have in the past used FORTRAN, but it has been completely replaced by 
> C++. I have also used Java, but it has now been replaced by Python.
> 
> 	By "use" I mean I have written > 50,000 lines of code,
> 	so I am (or was) expert. I have written less code in Ruby,
> 	SNOBOL, BASIC, ALGOL, lisp, HTML+Javascript+PHP, bash, and
> 	assembly languages of nearly a dozen CPUs. Unusually, I have
> 	written or been the primary architect and developer of three
> 	different real-time OS kernels (Z80, BELLMAC-8, PowerPC).

SNOBOL! Hehehe. How about Simula? I programmed in it in the 1970s,
before even the WORD "object-oriented" existed. Typed nicely on the
80-column Hollerith cards on the Juki punch machines.

--
Jan

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#477694

On Tuesday, November 20, 2018 at 8:21:46 PM UTC-7, JanPB wrote:
>
> On Tuesday, November 20, 2018 at 5:55:29 PM UTC-8, tjrob137 wrote:
> >
> > On 11/20/18 4:06 PM, JanPB wrote:
> > >
> > > [... programming languages]
> > 
> > I am both physicist and professional software developer. To me, the 
> > choice of programming language is secondary -- I always choose libraries 
> > that support what I am doing [#]; I can learn a new programming language 
> > in a day or two. So for particle simulations, I use C++ because of the 
> > Geant4 and CLHEP toolkits. For simple analyses and plotting, I use 
> > Python because of numpy, scipy, and matplotlib. For GUIs, C++/Qt and 
> > Python/tkinter are quite different but I use both, depending on what 
> > they are interfacing to.
> > 
> > 	[#] Choice of programming language affects productivity
> > 	at the 10% level; choice of libraries affects it by
> > 	factors of 10 to 1000 or more. Geant4 makes possible
> > 	programs that would be utterly infeasible without it (due
> > 	to the _physics_ that went into it).
> > 
> > I have in the past used FORTRAN, but it has been completely replaced by 
> > C++. I have also used Java, but it has now been replaced by Python.
> > 
> > 	By "use" I mean I have written > 50,000 lines of code,
> > 	so I am (or was) expert. I have written less code in Ruby,
> > 	SNOBOL, BASIC, ALGOL, lisp, HTML+Javascript+PHP, bash, and
> > 	assembly languages of nearly a dozen CPUs. Unusually, I have
> > 	written or been the primary architect and developer of three
> > 	different real-time OS kernels (Z80, BELLMAC-8, PowerPC).
> 
> SNOBOL! Hehehe. How about Simula? I programmed in it in the 1970s,
> before even the WORD "object-oriented" existed. Typed nicely on the
> 80-column Hollerith cards on the Juki punch machines.
> 
> --
> Jan

Ah, the good ol' keypunch machines.  Make a mistake and start a new card
'cause you can't find your hole-eraser.

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#477739

On 11/20/18 9:44 PM, Gary Harnagel wrote:
> Ah, the good ol' keypunch machines.  Make a mistake and start a new card
> 'cause you can't find your hole-eraser.

At Fermilab they prohibited hole fillers (erasers), as they would clog 
the high-speed card readers. Those readers were amazing to watch -- a 
whole tray of cards (4000 IIRC) in about 10 seconds, and amazingly quiet.

Sometime ~ 1978, the introduction of teletype machines (110 baud) was a 
revolution, and almost overnight we changed from card decks to 
disk-stored programs. And shortly thereafter, 10-20% of terminal use was 
playing Adventure games ("You are in a maze of twisty little passages 
all alike.").

	This was in the "Antique Computer Museum" on the 7th floor,
	so-named because the computers were rather old. When a new
	Amdahl computer arrived, they took out a window and used a
	tall crane to get it in. The new Feynman Computing Center
	has machine rooms on the same level as the loading dock.

Tom Roberts

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#477779

On Wednesday, November 21, 2018 at 10:20:14 AM UTC-8, tjrob137 wrote:
> On 11/20/18 9:44 PM, Gary Harnagel wrote:
> > Ah, the good ol' keypunch machines.  Make a mistake and start a new card
> > 'cause you can't find your hole-eraser.

Unless it's "Yellow Submarine".

> At Fermilab they prohibited hole fillers (erasers), as they would clog 
> the high-speed card readers. Those readers were amazing to watch -- a 
> whole tray of cards (4000 IIRC) in about 10 seconds, and amazingly quiet.

The only high(er) speed one I worked with was on a CDC Cyber mainframe.
First compressed air would inflate and separate slightly the cards next to
the scanning slot and then vrrrooomm, see them go. Not very quiet but not
very loud either.

--
Jan

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#477185

On 15/11/2018 18:54, Libor Striz wrote:
> Keith Stein <keithstein111@gmail.com> Wrote in message:
>> How to Program a Computer eh!
> 
> They have programmers for that.

But what you are completely missing Mr.Striz
is just how very much easier physics is, when
you know how to program a computer. You need
to learn to think like a computer, Mr.Striz.
> 
HOW WOULD A COMPUTER SOLVE THE PROBLEM eh!

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#477187

On Thursday, 15 November 2018 21:54:50 UTC+1, Keith Stein  wrote:
> On 15/11/2018 18:54, Libor Striz wrote:
> > Keith Stein <keithstein111@gmail.com> Wrote in message:
> >> How to Program a Computer eh!
> > 
> > They have programmers for that.
> 
> But what you are completely missing Mr.Striz
> is just how very much easier physics is, when
> you know how to program a computer. You need
> to learn to think like a computer, Mr.Striz.


Keith, computer doesn't think.
It's stupider even than a physicist.

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#477202

On 15/11/2018 21:07, mlwozniak@wp.pl wrote:
> On Thursday, 15 November 2018 21:54:50 UTC+1, Keith Stein  wrote:
>> On 15/11/2018 18:54, Libor Striz wrote:
>>> Keith Stein <keithstein111@gmail.com> Wrote in message:
>>>> How to Program a Computer eh!
>>>
>>> They have programmers for that.
>>
>> But what you are completely missing Mr.Striz
>> is just how very much easier physics is, when
>> you know how to program a computer. You need
>> to learn to think like a computer, Mr.Striz.
> 
> 
> Keith, computer doesn't think.
> It's stupider even than a physicist.
> 

While what you say is true, Mr.Wozniak, nevertheless
they can play a better game of chess than you or i,
and with help from a competent physicist they can solve
the 'n-body problem', when you or i would struggle with
predicting the paths of anything more than two, without
the aid of a computer eh!

keith stein

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#477205

Keith Stein wrote on 16.11.18 03:07:
> On 15/11/2018 21:07, mlwozniak@wp.pl wrote:
>> On Thursday, 15 November 2018 21:54:50 UTC+1, Keith Stein  wrote:
>>> On 15/11/2018 18:54, Libor Striz wrote:
>>>> Keith Stein <keithstein111@gmail.com> Wrote in message:
>>>>> How to Program a Computer eh!
>>>> They have programmers for that.
>>>
>>> But what you are completely missing Mr.Striz
>>> is just how very much easier physics is, when
>>> you know how to program a computer. You need
>>> to learn to think like a computer, Mr.Striz.
>> Keith, computer doesn't think.
>> It's stupider even than a physicist.
> 
> While what you say is true, Mr.Wozniak, nevertheless
> they can play a better game of chess than you or i,

After programmed so by "you and me", and maybe after having been trained
by "you and me" for quite a while.  That is not thinking, and there is
reasonable concern about machines that could think independently as they
need not be guided by the same moral framework as humans.

> and with help from a competent physicist they can solve
> the 'n-body problem',

But only for special cases.

-- 
PointedEars

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

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#477219

On 16/11/2018 02:25, Thomas 'PointedEars' Lahn wrote:
> Keith Stein wrote on 16.11.18 03:07:
>> On 15/11/2018 21:07, mlwozniak@wp.pl wrote:
>>> On Thursday, 15 November 2018 21:54:50 UTC+1, Keith Stein  wrote:
>>>> On 15/11/2018 18:54, Libor Striz wrote:
>>>>> Keith Stein <keithstein111@gmail.com> Wrote in message:
>>>>>> How to Program a Computer eh!
>>>>> They have programmers for that.
>>>>
>>>> But what you are completely missing Mr.Striz
>>>> is just how very much easier physics is, when
>>>> you know how to program a computer. You need
>>>> to learn to think like a computer, Mr.Striz.
>>> Keith, computer doesn't think.
>>> It's stupider even than a physicist.
>>
>> While what you say is true, Mr.Wozniak, nevertheless
>> they can play a better game of chess than you or i,
> 
> After programmed so by "you and me", and maybe after having been trained
> by "you and me" for quite a while.  That is not thinking, and there is
> reasonable concern about machines that could think independently as they
> need not be guided by the same moral framework as humans.

I see what you mean, if you mean what I SAID eh!
and right here and now i will demonstrate just HOW RIGHT YOU ARE
by hitting the "paste" and my computer without any moral judgement

On 24/03/2018 08:36, Keith Stein wrote:
 > Searching for an alternative explanation of the Hubble Red Shifts, it
 > occurred to me that if the speed of light is slowing down, then this
 > will necessarily lead to increasing red-shift with increasing
 > distance, as observed by Hubble et. al., without any expansion at all.
 >
 > Merely by assuming      dc = -K c dt ..................(1)
 > I was led to             c = c(0) e^-Kt ...............(2)
 > and on to               Red-Shift = e^-Kt - 1 .........(3)
 >
 >      K ~= 10^-10 /year
 >      t = time in years
 >
 > Only after starting the PHYSICS PRIZE thread, in which i was trying to
 > enlist the help of sci.physics.relativity readers to obtain a more
 > accurate value of K, did the obvious solution occur to me...........
 >
 >                         K = H = Hubble's Constant
 > and                    t = -t  ( so times past become +ve)
 >
 > which substituted in (3) gives:
 >
 >              Red-Shift = e^Ht - 1 .........(4)
 >
 > then for times which are small compared to 1/H (i.e. small compared
 > to the 'age of the universe'), we may use the approximation:
 >              e^x ~= 1 + x .................(5)
 >
 > So for t << 1/H we have:
 >
 >              Red-Shift = H * t ............(6)
 >
 > which is of course the normal "Hubble's Law", valid only
 > for modest times into the past ( t < ~5 billion years).
 >
 > As our telescopes manage to see further out into space, and therefore 
 > further back in time, we will find that the normal linear Hubble's 
Law > expressed in equation(6), will have to be replaced by the more
 > accurate exponential form expressed in equation(4). This is indeed
 > what is found  in observatories all around the world eh!


The Joys of the UNCENSORED CLIPBOARD eh! Thomas?




>> and with help from a competent physicist they can solve
>> the 'n-body problem',
> 
> But only for special cases.

if you mean that they need to be told the "Initial Conditions"
of all n bodies eh!
  then once again
YOU ARE RIGHT Thomas.

keith stein

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#477259

Keith Stein wrote on 16.11.18 14:34:
> On 16/11/2018 02:25, Thomas 'PointedEars' Lahn wrote:
>> Keith Stein wrote on 16.11.18 03:07:
>>> and with help from a competent physicist they can solve
>>> the 'n-body problem',
>> But only for special cases.
> 
> if you mean that they need to be told the "Initial Conditions"
> of all n bodies eh!

No, I mean that I remember to have heard in one of the recent lectures that
presently it is not possible to solve this problem for an arbitrary number
of bodies even with the best supercomputers.

-- 
PointedEars

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

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#477272

On 16/11/2018 18:50, Thomas 'PointedEars' Lahn wrote:
> Keith Stein wrote on 16.11.18 14:34:
>> On 16/11/2018 02:25, Thomas 'PointedEars' Lahn wrote:
>>> Keith Stein wrote on 16.11.18 03:07:
>>>> and with help from a competent physicist they can solve
>>>> the 'n-body problem',
>>> But only for special cases.
>>
>> if you mean that they need to be told the "Initial Conditions"
>> of all n bodies eh!
> 
> No, I mean that I remember to have heard in one of the recent lectures that
> presently it is not possible to solve this problem for an arbitrary number
> of bodies even with the best supercomputers.


Well clearly it does depend on how big you want to make n, and
how long you are prepared to wait for the answer, but even a
modest little desktop like my own could certainly model the
solar system, if i asked it to eh! Mr. Lahn.

keith stein
> 

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#477279

Keith Stein wrote on 16.11.18 21:46:
> On 16/11/2018 18:50, Thomas 'PointedEars' Lahn wrote:
>> No, I mean that I remember to have heard in one of the recent lectures that
>> presently it is not possible to solve this problem for an arbitrary number
>> of bodies even with the best supercomputers.
> 
> Well clearly it does depend on how big you want to make n, and
> how long you are prepared to wait for the answer, but even a
> modest little desktop like my own could certainly model the
> solar system, if i asked it to eh! Mr. Lahn.

Not even remotely.  Do you even know how many celestial bodies there are
in the Sol system alone?

You must not confuse a simplified simulation like Celestia with a proper
computer model.
 --
PointedEars

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

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#477283

On 16/11/2018 21:36, Thomas 'PointedEars' Lahn wrote:
> Keith Stein wrote on 16.11.18 21:46:
>> On 16/11/2018 18:50, Thomas 'PointedEars' Lahn wrote:
>>> No, I mean that I remember to have heard in one of the recent lectures that
>>> presently it is not possible to solve this problem for an arbitrary number
>>> of bodies even with the best supercomputers.
>>
>> Well clearly it does depend on how big you want to make n, and
>> how long you are prepared to wait for the answer, but even a
>> modest little desktop like my own could certainly model the
>> solar system, if i asked it to eh! Mr. Lahn.
> 
> Not even remotely.  Do you even know how many celestial bodies there are
> in the Sol system alone?
> 
> You must not confuse a simplified simulation like Celestia with a proper
> computer model.

I am not talking about running same packaged simulation on my computer,
Mr.Lahn, I am talking about writing a model of the solar system in a
high level computer language,  BASIC would be my choice, but C++ would
probably be the professionals choice, it really doesn't matter, so long
as one appreciates just how it is done eh!

keith stein

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

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#477285

Keith Stein wrote on 16.11.18 23:10:
> On 16/11/2018 21:36, Thomas 'PointedEars' Lahn wrote:
>> Keith Stein wrote on 16.11.18 21:46:
>>> Well clearly it does depend on how big you want to make n, and
>>> how long you are prepared to wait for the answer, but even a
>>> modest little desktop like my own could certainly model the
>>> solar system, if i asked it to eh! Mr. Lahn.
>> Not even remotely.  Do you even know how many celestial bodies there are
>> in the Sol system alone?
>>
>> You must not confuse a simplified simulation like Celestia with a proper
>> computer model.
> 
> I am not talking about running same packaged simulation on my computer,
> Mr.Lahn, I am talking about writing a model of the solar system in a
> high level computer language,  BASIC would be my choice, but C++ would
> probably be the professionals choice, it really doesn't matter, so long
> as one appreciates just how it is done eh!

You have no clue what you are talking about there, too.

FYI, according to my astronomy textbook of 2009, in addition to the star,
Sol, and the 8 planets, the Sol system consists of more than 100 moons,
ca. 10 million asteroids; ca. 1 billion, short scale, transneptunian objects
(TNOs); ca. 10 million to 100 billion comets, and a gazillion meteoroids.
Not counting any of the orbiting spacecraft and debris, which are tens of
thousands.

And those are just *estimations* of the objects *known* *in 2009*.

-- 
PointedEars

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

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#477300

On 16/11/2018 22:25, Thomas 'PointedEars' Lahn wrote:
> Keith Stein wrote on 16.11.18 23:10:
>> On 16/11/2018 21:36, Thomas 'PointedEars' Lahn wrote:
>>> Keith Stein wrote on 16.11.18 21:46:
>>>> Well clearly it does depend on how big you want to make n, and
>>>> how long you are prepared to wait for the answer, but even a
>>>> modest little desktop like my own could certainly model the
>>>> solar system, if i asked it to eh! Mr. Lahn.
>>> Not even remotely.  Do you even know how many celestial bodies there are
>>> in the Sol system alone?
>>>
>>> You must not confuse a simplified simulation like Celestia with a proper
>>> computer model.
>>
>> I am not talking about running same packaged simulation on my computer,
>> Mr.Lahn, I am talking about writing a model of the solar system in a
>> high level computer language,  BASIC would be my choice, but C++ would
>> probably be the professionals choice, it really doesn't matter, so long
>> as one appreciates just how it is done eh!
> 
> You have no clue what you are talking about there, too.
> 
> FYI, according to my astronomy textbook of 2009, in addition to the star,
> Sol, and the 8 planets, the Sol system consists of more than 100 moons,
> ca. 10 million asteroids; ca. 1 billion, short scale, transneptunian objects
> (TNOs); ca. 10 million to 100 billion comets, and a gazillion meteoroids.
> Not counting any of the orbiting spacecraft and debris, which are tens of
> thousands.
> 
> And those are just *estimations* of the objects *known* *in 2009*.

Well it may be a little difficult to find accurate initial conditions 
for all those millions, and billions and gazillion objects, and even if
you did find it it's going to take more than one evening to type it all
in at the keyboard eh! You might be better advised just to stick with
the sun, planets, and maybe our moon for starters Thomas. Can we take
it that you could write the program to simulate that mini solar system 
Thomas?


> 

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#477326

Keith Stein wrote on 17.11.18 03:44:
> On 16/11/2018 22:25, Thomas 'PointedEars' Lahn wrote:
>> FYI, according to my astronomy textbook of 2009, in addition to the star,
>> Sol, and the 8 planets, the Sol system consists of more than 100 moons,
>> ca. 10 million asteroids; ca. 1 billion, short scale, transneptunian objects
>> (TNOs); ca. 10 million to 100 billion comets, and a gazillion meteoroids.
>> Not counting any of the orbiting spacecraft and debris, which are tens of
>> thousands.
>>
>> And those are just *estimations* of the objects *known* *in 2009*.
> 
> Well it may be a little difficult to find accurate initial conditions 
> for all those millions, and billions and gazillion objects, and even if
> you did find it it's going to take more than one evening to type it all
> in at the keyboard eh!

The initial conditions are not main problem, the *equations of motion* are:

<https://en.wikipedia.org/wiki/N-body_problem>

And one would certainly not type in the initial conditions.

> You might be better advised just to stick with the sun, planets, and maybe
> our moon for starters Thomas. Can we take it that you could write
> the program to simulate that mini solar system Thomas?
Wrong question.  You are missing the point.  AISB, you are mistaking
simplified simulations for accurate models of planetary system dynamics.

-- 
PointedEars

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

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#477332

Keith Stein wrote:

> On 16/11/2018 22:25, Thomas 'PointedEars' Lahn wrote: 
>> FYI, according to my astronomy textbook of 2009, in addition to the
>> star,
>> Sol, and the 8 planets, the Sol system consists of more than 100 moons,
>> ca. 10 million asteroids; ca. 1 billion, short scale, transneptunian
>> objects (TNOs); ca. 10 million to 100 billion comets, and a gazillion
>> meteoroids.
>> And those are just *estimations* of the objects *known* *in 2009*.
> 
> Well it may be a little difficult to find accurate initial conditions
> for all those millions, and billions and gazillion objects, and even if

Never again try to contradict a german. You don't know what those people 
can do. They can be the reason for generated, unneeded, unspeakable pain.

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