WHAT WE CANNOT KNOW

The dou­ble-slit expe­ri­ment men­tio­ned in the text,
con­sists of pas­sing a light ray throu­gh two sli­ts made in an opa­que barrier
and then obser­ving the figu­re for­med on a screen at the back.
It was fir­st con­cei­ved by Tho­mas Young in 1801,
repea­ted and impro­ved many times sin­ce then, until the years 2000 with elec­trons too.
It shat­ters in the most chee­ky way, the firm deter­mi­na­cy of clas­si­cal phy­sics we are used to.
With it, eve­ry­thing in our world beco­mes fluc­tua­ting, inde­ter­mi­na­te, dou­ble, pro­ba­ble, statistical,
… to an extent that we are not even aware of today.
So much so that the Nobel Pri­ze win­ner Richard Feyn­man sta­ted that
for the pro­gress of scien­ce, uncer­tain­ty is a fun­da­men­tal part of the dee­per natu­re itself.
If inde­ter­mi­na­cy is a foun­da­tion of reality,
the phi­lo­so­phy of the last cen­tu­ry at lea­st, had also to endu­re the chal­lan­ge.  (a. m. III/’22)

| | | | |

I don’t demand that a theo­ry cor­re­spond to reality,
becau­se I don’t know what it is.
Rea­li­ty is not a qua­li­ty you can test with lit­mus paper.
All I’m con­cer­ned with is that the theo­ry should pre­dict the resul­ts of measurements.
S. Haw­king

     My real pro­blem with the cur­rent main­stream inter­pre­ta­tion on quan­tum phy­sics is that if you run the dou­ble slit expe­ri­ment twi­ce, setup with exac­tly the same con­di­tions, the out­co­me can be dif­fe­rent each time. This goes again­st eve­ry­thing I belie­ve in. It is why I was dra­wn to mathe­ma­tics: the cer­tain­ty of the proof that the­re are infi­ni­te­ly many pri­me num­bers means I’m not sud­den­tly going to get fini­te­ly many pri­me num­bers next time I check.
I belie­ve that the ulti­ma­te­ly scien­ce was made up of simi­lar cer­tain­ties, even if we as humans might not ultim­te­ly have access to them.
I throw my dice and the mathe­ma­tics of chaos theo­ry I reco­gni­ze means I may never be able to cal­cu­la­te the final out­co­me of the throw of the dice. But at lea­st the mathe­ma­tics says that I start the throw in the same pla­ce it will end up with the same face poin­ting up. But now the phy­sics deve­lo­ped in this Edge fun­da­men­tal­ly, que­stions whea­ther this is the case.
Pro­ba­bi­li­ty for the dice is an expres­sion of lack of infor­ma­tion. In quan­tum phy­sics it’s not about the physicist’s igno­ran­ce of the com­ple­te pic­tu­re. Even if I knew eve­ry­thing, pro­ba­bi­li­ty and chan­ce remain. Accor­ding to cur­rent inter­pre­ta­tions of quan­tum phy­sics, dif­fe­rent out­co­mes of the roll of the dice real­ly can result from the same star­ting point, the same input.
Some would que­stion if it makes sen­se to talk about set­ting up the expe­ri­ment and run­ning it again with exac­tly te same con­di­tions – that in fact it is an impos­si­bi­li­ty. Local­ly you might get the con­di­tions exac­tly the same, but you have to embed the expe­ri­ment in the uni­ver­se, and that has moved on. You can’t rewind the wave func­tion of the uni­ver­se and rerun it.
The uni­ver­se is a one-time-only expe­ri­ment which inclu­de us as part of its wave func­tion. Each obser­va­tion chan­ges the wave func­tion of the uni­ver­se and there’s no going back.

The wave func­tion descri­bes the sta­te of a system
– that means the con­di­tions of any­thing you can think of – in a cer­tain instant.
You can get velo­ci­ty, ener­gy, posi­tion and so on, of a par­ti­cle or of all the Uni­ver­se on your fingertip.
Ama­zing isn’t it ? But, but, but, not precisely;
you will be able to know only the pro­ba­bi­li­ty of the­se sta­tes in that exact moment !
And if you say it’s a mess, you are right.
The same Erwin Rudolf Josef Ale­xan­der Schrödinger,
fra­mer of the Wave function’s equa­tions in 1926 and Nobel Pri­ze in 1933, said …
« If the­se damn quan­tum jumps were to exist,
I would regret having taken up quan­tum mechanics!»
Any­way this is the sta­te of the Art,
hol­ding up with plen­ty of confirmations
for near­ly a century.

But what if rea­li­ty is ran­dom and not as deter­mi­ni­stic as I might want? Feyn­man in his Lec­tu­res on Phy­sics (1961-’63) sta­tes: «At the pre­sent time we must limit our­sel­ves to com­pu­ting pro­ba­bi­li­ties. We say “at the pre­sent time” but we suspect very stron­gly that it is some­thing that will be with us fore­ver – that it is impos­si­ble to bear the puzz­le – that it is the way natu­re real­ly is.» … .

——————————————————————

Mar­cus du Sau­toy   WHAT WE CANNOT KNOW
4th Esta­te ed. 2016 – pg. 157–8
                                                              all ita­lics: a.m. III’22