# [ExI] R: Re: Cramer on impossibility of FTL communication

John Clark johnkclark at gmail.com
Fri Sep 4 16:14:19 UTC 2015

```On Thu, Sep 3, 2015  Adrian Tymes <atymes at gmail.com> wrote:

> ​>> ​
>> 4) Some gears and pulleys so that each time the rotary switch is advanced
>> one position the filter is advanced by 30 degrees. This is because it's
>> been known for many years that the amount of light polarized at 0 degrees
>> that will make it through a polarizing filter set at X degrees is [COS
>> (x)]^2; and if x = 30 DEGREES then the value is .75
>>
>> ​> ​
> Here is where your analogy breaks.  (COS(60)^2)/2 != COS(30)^2 !=
> 2*(COS(60)^2).  So you can have full alignment at 0, 75% at 30 degrees, and
> 0 at 90; 60 degrees is neither 50% nor 25%.  This is not a direct
> consequence of quantum mechanics (save for the distribution of photons) or
> hidden variables, but rather how cosine is a non-linear function.
>

​Your math is right but not your physics. The original photon was NOT
polarized at zero degrees, it was oriented at an undetermined polarization
(or rather a undeterminable one). If that photon of undetermined
polarization makes it through that first filter set at 30 degrees (and
there is ALWAYS a 50% chance a unknown photon will make it through a filter
set at ANY angle) then after the photon gets past that first filter the
photon is no longer undetermined, it is now polarized at 30 degrees.

If the second filter is oriented at 30 degrees compared with the first
filter (or to say the same thing with different words, oriented at 30
degrees compared with the photon) then you can use the COS (x)]^2 formula
and get a value of .75.  After the second filter the photon is now  oriented
at 60 degrees. And if the third filter is it oriented at 30 degrees
compared with the second filter the same thing happens, there is a 75%
chance it will get through the second filter.

[COS (x)]^2 is of no use in determining the probability of a photon of
undetermined
polarization making it through a filter because you don't know what value
of x to plug into it, you may know the angle the filter is set at but you
don't know what angle the photon is at relative to that filter. But we do
know from experiment that the probability a photon of undetermined
polarization will make it through a filter set at ANY angle is 50%.

Yes this all sounds ridiculous but you can confirm that it's the way nature
actually works if you happen to have 3 pairs of polarizing sunglasses. Set
2 of them up at right angles and no light gets through, but place a third
pair set at 45 degrees between the two and light does get through.

​> ​
> Further, your original example assumes that because 12 o'clock and 2
> o'clock differ by a certain amount, that 2 o'clock and 4 o'clock must
> differ by the same amount.  That does not have to be the case.
>

​Certainly it doesn't have to be the case, you can make the boxes behave
differently just by changing the pulleys and gears that connect the clock
face switch with the mechanism that rotates the filter. The point isn't
that you have to make the boxes that way but that you can and classical
physics or even classical logic can not explain why they behave as they do.
It's just weird.      ​

> ​> ​
> If 12 o'clock represents perfect alignment with polarization,
>

​With regard to that first filter "perfect alignment" has no meaning, there
is always a 50% chance that a undetermined photon will make it through
regardless of what angle the filter is set at.

> ​> ​
> then 2 o'clock does not represent perfect alignment.
>

​If the second filter is set at the same angle ​as the first then there is
a 100% chance the photon will get through, if the second filter is

​90 degrees
different from ​the first there is a
​0​
% chance it will get through
​,​
​
if the second filter is
​ ​
30 degrees different from ​the first there is a 75% chance it will get
through.

> ​> ​
> The lookup table for 4 o'clock can be more different from 2 o'clock than 2
> o'clock is from 12 o'clock.
>

​If that were true the boxes would behave differently than the way we
observe they actually do. No lookup table can duplicate the way my boxes
behave, and my boxes could actually be built.

John K Clark ​
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.extropy.org/pipermail/extropy-chat/attachments/20150904/96008a52/attachment.html>
```