Jon Letendre

Where are you?

Recommended Posts

15 hours ago, Brant Gaede said:

Bob's not dumb.

No, he's dumb.

He's being childishly stubborn and refusing to consider evidence contrary to his stupid opinion. That's dumb. Willful ignorance is just as dumb as unintentional ignorance.

And it doesn't take much to understand the solutions other than the one that he accepts. It's quite likely that, like Merlin and Tony (and many other O-vish-types), Bob is severely lacking in cognitive abilities in the area of visuospatial/mechanical reasoning. In fact, he has already demonstrated that specific deficiency over on Aristotle's Wheel Paradox thread. He couldn't grasp this simple scenario.

He pretends to be a math wiz, but that's bluff. It's a pose. He's been shown the math on this thread, and he doesn't get it. It's over his head.

J

  • Like 1

Share this post


Link to post
Share on other sites
13 hours ago, BaalChatzaf said:

Science parted company with metaphysics  over 100 years go.  The only philosopher  that  physicists mention without spitting is Carl Popper. 

 

On this thread, no one has cited philosophy or metaphysics, and no one has contradicted science. It's purely been about physical relationships. And yet you can't grasp it.

J

  • Like 1

Share this post


Link to post
Share on other sites

Dumbness is not a personal moral failing but posturing and insults followed by refusal to acknowledge error or apologize certainly are. Serious ones, too. They indicate you are dealing with a very small person.

Share this post


Link to post
Share on other sites

Ah, finally I got the 3rd graph belonging to this post uplodaded:

 

graph2a.thumb.gif.987728b47c0a773b9c6050622ade42f8.gif

I just realized that I should have saved those graphs in GIF format, which in this case is much more efficient. I still had to cut a part with explanations of the symbols to get it small enough, but these are the same as on the previous graph. so that's no great loss. 

But I'd still like to now how long I must wait before my upload limit is reset again. Obviously more than a day; a week, a month, a year, forever...?

  • Like 1

Share this post


Link to post
Share on other sites
23 minutes ago, Darrell Hougen said:

Okay guys, I'm here now. Now that this problem has been beaten to death, I'm ready to jump right in.

First get hosed down. You have to start off clean so you don't contaminate the pool.

--Brant

1) Are you an admirer of Ann Band?

2) Have you read Atlas Bugged?

3) Whose side are you on - HERS or his?

  • Haha 1

Share this post


Link to post
Share on other sites
3 hours ago, Max said:

Ah, finally I got the 3rd graph belonging to this post uplodaded:

 

graph2a.thumb.gif.987728b47c0a773b9c6050622ade42f8.gif

I just realized that I should have saved those graphs in GIF format, which in this case is much more efficient. I still had to cut a part with explanations of the symbols to get it small enough, but these are the same as on the previous graph. so that's no great loss. 

But I'd still like to now how long I must wait before my upload limit is reset again. Obviously more than a day; a week, a month, a year, forever...?

That’s nice work, Max. I’m sure it felt good to nail it down.

Share this post


Link to post
Share on other sites
On 1/13/2019 at 11:44 AM, Max said:

I‘ ve made some calculations for the general case with arbitrary distance Z for the 3 legs of the trip, instead of 1 mile. The calculations are made for an idealized Earth as a perfect sphere, with radius R = 6400 km. See the first figure for the meaning of the different symbols, the drawing is not to scale!

earth.thumb.jpg.ca24aad10d0896548d6460d2408491fb.jpg

The trip starts anywhere on the upper circle with radius r2, goes southwards along a meridian over a distance Z km, then westwards along a circle with circumference Z and radius r1 = Z / 2π, and then back northwards.

 

2π * r1 = Z r1 = Z / 2π

a2 + r12 = R2 a = (R2 – r12)

sin (β) = r1 / R

sin (β + γ) = r2 / R = sin (β) * cos (γ) + cos (β) * sin (γ)

= (r1 / R) * cos (Z / R) + (a / R) * sin (Z / R)

r2 = r1 * cos (Z / R) + ( (R2 – r12)) * sin (Z / R)

 

With these expressions we can now draw a graph of the different variables r1, r2, M and M + Z as a function of Z, see the second figure.*) At the left, for relatively low values of Z, these variables have a linear dependence on Z, but for larger values of Z especially r2 is going to deviate, reaches a maximum and than decreases again to zero, meaning that the radius of the upper circle can increase to the radius of the Earth and then diminishes as the circle becomes smaller when it moves to the North. Finally it shrinks to a point, the North Pole, larger values of Z therefore have no physical meaning.

 

In the next figure *) the first 20 kilometers for Z are given. Here all the variables are quite linear and M r1, and M + Z ≈ r2. For small Z/R the expression for r2 becomes

 

r2 r1 – r1* Z2/(2!*R2) + R (1 – r12/R2) * (Z/R – Z3/(3!*R3)) =

= r1 + Z + O(Z2/R2)

 

as you’d expect when the curvature of the Earth may be neglected. In the graph the value of 1 mile = 1.609344 kilometers is indicated, with the corresponding values for r1 and r2. The large number of decimals seems to be overdone, but this is just to show how small the difference between the exact values and the approximated values in this case is.

 

*) Uh oh, too big to upload here, I'll try it in a separate message

 

It’s interesting to see what you were working on. I follow your method now that you have presented it but I probably would not myself have been able to develop the general case, as you have done, and certainly would not have been able to finish the math.

Share this post


Link to post
Share on other sites
4 hours ago, Jon Letendre said:

Dumbness is not a personal moral failing but posturing and insults followed by refusal to acknowledge error or apologize certainly are. Serious ones, too. They indicate you are dealing with a very small person.

Or an aspie?

I call it the self esteem lock down--that is, one mixes up one's ideas with one's self evaluation and it all freezes up. 

Then there are those who mix up their ideas with their real or merely perceived social group as with politicalized science or modern journalism.

Etc.

--Brant

I work with--dance with--reality

Share this post


Link to post
Share on other sites
1 hour ago, Brant Gaede said:

Or an aspie?

I call it the self esteem lock down--that is, one mixes up one's ideas with one's self evaluation and it all freezes up. 

Then there are those who mix up their ideas with their real or merely perceived social group as with politicalized science or modern journalism.

Etc.

--Brant

I work with--dance with--reality

It’s a character flaw. It is observable from where I am but only he may understand its origins or motivation. It is one of the more irrational ones, too. It has always deeply amazed and puzzled me. I’ve seen many cases.

Another, similar, is the liar who sticks to the lie even after plain demonstration of its status as a lie. It’s like they think plausible doubt is still somehow maintained  Of course the way to preserve one’s reputation at that point is to reverse oneself, but they imagine that the better way is to prove to you that they neither care about the truth nor see you as someone who deserves any. Comically irrational.

Share this post


Link to post
Share on other sites
16 hours ago, Jon Letendre said:

It’s a character flaw. It is observable from where I am but only he may understand its origins or motivation. It is one of the more irrational ones, too. It has always deeply amazed and puzzled me. I’ve seen many cases.

Another, similar, is the liar who sticks to the lie even after plain demonstration of its status as a lie. It’s like they think plausible doubt is still somehow maintained  Of course the way to preserve one’s reputation at that point is to reverse oneself, but they imagine that the better way is to prove to you that they neither care about the truth nor see you as someone who deserves any. Comically irrational.

Who you gunna believe, me or your lyin' eyes?

Share this post


Link to post
Share on other sites
On 1/14/2019 at 9:20 PM, Jon Letendre said:

It’s a character flaw. It is observable from where I am but only he may understand its origins or motivation. It is one of the more irrational ones, too. It has always deeply amazed and puzzled me. I’ve seen many cases.

Another, similar, is the liar who sticks to the lie even after plain demonstration of its status as a lie. It’s like they think plausible doubt is still somehow maintained  Of course the way to preserve one’s reputation at that point is to reverse oneself, but they imagine that the better way is to prove to you that they neither care about the truth nor see you as someone who deserves any. Comically irrational.

There might be a sense of entitlement--idea or position entitlement--at play and you heroically man the barricades to protect them. This is understandable with the young and ignorant. Ignorance of ignorance.

--Brant

Share this post


Link to post
Share on other sites
On 1/5/2019 at 9:22 AM, BaalChatzaf said:

 

 

The original problem was walk a mile south walk a mile west (was it east -- no matter)  walk a mile north.  The east-west walk  is less than the length of line of latitude  reached by the southword leg so that the return trip is along a  different line of longitude.   Let me give an example.  The coordinates of the north geographic pole  are (90, lon)  where lon can be any angle between 0 and 360.  The north geographic pole and the south geographic pole are the only two points on the earth sphere that do not have unique coordinate.  Now let me widen the problem out   Start at a  point, walk to the equator in a southerly direction, walk east along the equator  the same number of steps that one took to reach the equator  then march in a northerly direction  the same number of step.   

Two cases:   

Case 1  the starting point is the north pole.   Assume the first leg is south along the Greenwich meridian, that is to say 0 longitude.  This gets us  down to (0, 0) on the equator.  Walk west the same distance and we get to (0, 90).  Now walk north the same distance and we get to (90,90) which is the same point as (90, 0)   the north pole.

Case 2.  The starting point  is   (x-lat, x-long)  where x-lat is greater than 0 and less than 90.   Assume  x-long = 0 without loss of generality.   Now leg 1: (x-lat, 0)  to (x1, 0)  where x1 < x-lat  and greater or  equal to 0.   Leg  2  (x1,0)   (x1, y1)  where  y1 > 0  but < 360.   That means leg2 moved us to a different point with the same latitude.  Now leg 3  northward by the same distance.  This gets is to (x2, y1) because going north means following a meridian of longitude.   Notice that x2 not = x1.   The final destination is (x2, y1)  which is different from (x-lat, 0).  So we do not end up at the same place if we started out from a point that was not the pole. 

Q.E.D.

Forget drawings.  The proof is abstract and mathematical.  Drawings are crutches for the logically feeble. 

 

“Crutches for the logically feeble.”

Not another word from Bob since.

Pure pomp and disappearance.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...