Bylgjulķkir eiginleikar ljóss, fręgri tilraun sem Thomas Young gerši fyrst snemma į nķtjįndu öld. Ķ upphaflegri tilraun lżsir punktljós upp tvęr mjóar ašliggjandi raufar į skjįnum og myndin af ljósinu sem fer ķ gegnum raufin sést į öšrum skjį.

Žś veršur aš lesa nišur aš 000000, ca 20 lķnur

Hér lżsa žeir myndpunkti ķ heilmyndinni. jg

Here they describe an image point in the hologram. jg

 

Sś stašreynd aš skammtakerfi, svo sem rafeindir og róteindir, hafa óįkvešna žętti žżšir aš žau eru til sem möguleikar frekar en rauneiginleikar. Žetta gefur žeim žann eiginleika aš vera hlutir sem gętu veriš eša gętu gerst, frekar en hlutir sem eru. Žetta er ķ skörpri mótsögn viš ešlisfręši Newtons žar sem hlutirnir eru eša ekki, žaš er engin óvissa nema žau sem sett eru vegna lélegra gagna eša takmarkana į gagnaöflunarbśnašinum.

Frekari tilraunir sżndu aš raunveruleikinn į skammtafręšilegu (smįsjį) stigi samanstendur af tvenns konar veruleika, raunverulegum og möguleikum. Raunverulegt er žaš sem viš fįum žegar viš sjįum eša męlum skammtaeiningu,

(Žegar viš horfum į geislaskjįinn hans Nikola Tesla žį kveikir hann og viš sjįum myndpunktinn sem birtir hinar og žessar myndir sem eru, viš setjum, leikum ķ heilmyndinni jg)

möguleikinn er įstandiš žar sem hluturinn (myndpunkturinn įšur en kveikt var į honum meš įhorfi jg) var til įšur en hann var męldur.

(Nišurstašan er sś aš skammtaeining (ljóseind, rafeind, nifteind o.s.frv.) er til ķ mörgum möguleikum raunveruleika sem kallast superpositions. (Eins og myndpunkturinn ķ nśtķma sjónvarpi er til en žį ekki meš myndtjįninguna, slöktur jg)

Hęgt er aš sżna fram į yfirbyggingu mögulegra stašsetninga rafeindar meš athugušu fyrirbęri sem kallast skammtagöng.

000000

Ef heimurinn er heilmynd , hvaš kveikir eša slekkur į henni. Er žaš upplżsandinn, sį sem beinir athygli aš, skošar, viršir fyrir sér, horfir į, er žįtt takandi, leikari ķ heilmyndinni sem veršur til viš geršir og višbrögš, žįtttakenda.

If the world is a hologram, what turns it on or off. Is it the informant, the one who pays attention to, examines, observes, watches, is a participant, an actor in the hologram created by the actions and reactions of the participants.

000

Nś į ég eftir aš finna śt hvernig og hvort ég hef tķma til aš fęra myndirnar. Ég gef mér ekki tķma til aš lesa žetta yfir, fer śt aš hjóla, hef nagla į hjólunum allt įriš. snjóžekja um 5 sentimetrar. 

 

Hér er greinin į tölvu ķslensku ķ Word: klikka slóš

http://www.herad.is/00/2022-12-07-two-riffts/ 

 

Bylgjulķkir eiginleikar ljóss, fręgri tilraun sem Thomas Young gerši fyrst snemma į nķtjįndu öld. Ķ upphaflegri tilraun lżsir punktljós upp tvęr mjóar ašliggjandi raufar į skjįnum og myndin af ljósinu sem fer ķ gegnum raufin sést į öšrum skjį.

7.12.2022 | 12:27

1.1.1970 | 00:00

Ef ég mį ekki kynna žetta svona, žį tek ég žaš strax nišur.

Tveggja rifa tilraunir (uoregon.edu)

Žaš er betra aš horfa į slóšina hér nešan viš.

http://abyss.uoregon.edu/~js/21st_century_science/lectures/lec13.html

 

Tilraun meš ungum tveimur raufum:

 

Lestur:

tvęr raufartilraunir Kaupmannahöfn InterpretationQuantum Mechanics

 

§  tilraunin meš tveimur rifum er lykillinn aš žvķ aš skilja smįsjįrheiminn

§   

§  Tveggja rifa tilraunin er lykillinn aš žvķ aš skilja smįsjįrheiminn

Bylgjulķkir eiginleikar ljóss voru sżndir meš fręgri tilraun sem Thomas Young gerši fyrst snemma į nķtjįndu öld. Ķ upphaflegri tilraun lżsir punktljós upp tvęr mjóar ašliggjandi raufar į skjįnum og myndin af ljósinu sem fer ķ gegnum raufin sést į öšrum skjį. 

Bylgjukenndir eiginleikar ljóssins voru sżndir meš hinni fręgu tilraun sem Thomas Young gerši fyrst snemma į nķtjįndu öld. Ķ upphaflegri tilraun lżsir ljósgjafi upp tvęr mjóar samliggjandi raufar į skjį og myndin af ljósinu sem fer ķ gegnum raufarnar sést į öšrum skjį.

 

 

 

Smelltu hér til aš trufla eftirlķkingu

 

§  Bylgjur geta truflaš, fyrir ljós mun žetta gera röš af ljósum og dökkum böndum

§  efnisagnir, eins og rafeindir, framleiša einnig truflunarmynstur vegna bylgjulķks ešlis žeirra

§  Svo meš miklu flęši annaš hvort ljóseinda eša rafeinda er einkennandi truflunarmynstriš sżnilegt

Dökku og ljósu svęšin eru kölluš vķxlunarrįkir, uppbyggileg og eyšileggjandi truflun ljósbylgna. Svo spurningin er mun skipta mįli einnig framleiša truflunarmynstur. Svariš er jį, prófaš meš žvķ aš skjóta straumi rafeinda.

 

 

 

§  Ef viš lękkum ljósstyrkinn, eša flęši rafeinda (rafstrauminn), ęttum viš aš geta séš hverja ljóseind slį skjįinn

§  hver ljóseind gerir punkt į skjįnum, en hvar er truflunarmynstriš?

Takiš žó eftir aš rafeindir virka sem agnir, eins og ljóseindir. Til dęmis gera žeir eitt högg į bakskautslampaskjį. Žannig aš ef viš lękkum fjölda rafeinda ķ geislanum nišur ķ, segjum eina į sekśndu. Hverfur truflunarmynstriš?

 

 

 

§  truflunarmynstriš er enn til stašar, žaš tekur einfaldlega nokkurn tķma fyrir nęgar ljóseindir, eša rafeindir, aš slį į skjįinn til aš byggja upp žekkjanlegt mynstur

§  truflun, eša bylgjufyrirbęri, er enn aš eiga sér staš jafnvel žótt viš hleypum ašeins ljóseindum, eša rafeindum, ķ gegnum eina ķ einu

§  Svo hvaš eru einstakar agnir aš trufla? aš žvķ er viršist, sjįlfir

Svariš er nei, viš sjįum einstakar rafeindir (og ljóseindir) slį į skjįinn og meš tķmanum byggist truflunarmynstriš upp. Taktu eftir žvķ aš meš svo hęgum hraša hefur hver ljóseind (eša rafeind) ekki samskipti viš ašrar ljóseindir til aš framleiša truflunarmynstriš. Reyndar eru ljóseindirnar ķ samskiptum viš sjįlfa sig, innan eigin bylgjupakka til aš framleiša truflanir.

 

 

 

§  til žess aš ögn trufli sig veršur hśn aš fara ķ gegnum bįšar raufarnar

§  žetta neyšir okkur til aš gefa upp heilbrigša skynsemi hugmynd um stašsetningu

En bķddu, hvaš ef viš gerum žetta svo hęgt aš ašeins ein rafeind eša ein ljóseind fer ķ gegnum raufarnar ķ einu, hvaš er žį aš trufla hvaš? ž.e. žaš eru ekki tvęr bylgjur til aš trufla og trufla į uppbyggilegan hįtt. Žaš viršist, į einhvern undarlegan hįtt, aš hver ljóseind eša rafeind trufli sig. Aš bylgjuešli hennar trufli eigin bylgju (!).

Myndun truflunarmynstursins krefst žess aš til séu tvęr raufar, en hvernig getur ein ljóseind sem fer ķ gegnum eina rauf 'know' um tilvist hinnar rifunnar? Viš erum föst viš aš hugsa um hverja ljóseind sem bylgju sem lendir į bįšum raufunum. Eša viš veršum aš hugsa um ljóseindina sem klofna og fara ķ gegnum hverja rauf fyrir sig (en hvernig veit ljóseindin aš raufar koma?). Eina lausnin er aš gefa upp hugmyndina um ljóseind eša rafeind sem hefur stašsetningu. Stašsetning subatomic agna er ekki skilgreind fyrr en hśn er athuguš (s.s. aš slį į skjį).

 

 

Hlutverk įheyrnarfulltrśa:

§  Žar sem ekki er hęgt aš fylgjast meš skammtaheiminum beint, neyšumst viš til aš nota tęki sem framlengingu skynfęra okkar

§  žó, skammtaeiningar eru svo litlar aš jafnvel snerting viš eina ljóseind breytir stöšu žeirra og skrišžunga = męlingarvandamįl

§  1. vķsbending um aš athugandinn sé mikilvęgur hluti af skammtatilraun, getur ekki einangraš athugandann eša įhrif žeirra

Ekki er hęgt aš skynja skammtaheiminn beint, heldur meš žvķ aš nota męlitęki. Og svo, žaš er vandamįl meš žį stašreynd aš męlingarašgeršin truflar orku og stöšu subatomic agna. Žetta er kallaš męlingarvandamįliš.

 

 

 

§  Tveggja rifa tilraunin er góš prófraun į hlutverk athugandans ķ skammtasvišinu

§  öll tilraunahönnun žar sem reynt er aš įkvarša hvaša rauf ljóseind hefur fariš ķ gegnum (prófun į agnaešli hennar) eyšileggur truflunarmynstriš (bylgjulaga ešli hennar)

§  žetta er sundurlišun į hlutlęgum veruleika

§  Hver skammtaeining hefur tvķžętta mögulega eiginleika sem verša raunverulegt einkenni ef og žegar hśn er athuguš

Žannig byrjum viš aš sjį sterka tengingu eiginleika skammtahlutar og athöfnina aš męla žį eiginleika. Spurningin um raunveruleika skammtaeiginleika er enn óleyst. Allar skammtafręšilegar meginreglur verša aš hverfa til newtonķskra meginreglna į stórsęju stigi (žaš er samfella milli skammtafręšinnar og Newtonķskrar aflfręši).

Hvernig hefur hlutverk athugandans įhrif į bylgju- og agnaešli skammtaheimsins? Eitt próf er aš fara aftur ķ raufartilraunina tvęr og reyna aš įkvarša talningu hvaša rauf ljóseindin fer ķ gegnum. Ef ljóseindin er ögn, žį žarf hśn aš fara ķ gegnum eina eša ašra rauf. Aš gera žessa tilraun leišir til žess aš žurrka śt truflunarmynstriš. Bylgjuešli ljóssins er śtilokaš, ašeins agnaešliš er eftir og agnir geta ekki valdiš truflunarmynstri. Ljóst er aš raufartilraunirnar tvęr, ķ fyrsta skipti ķ ešlisfręši, benda til žess aš mun dżpra samband sé į milli athugandans og fyrirbęrisins, aš minnsta kosti į undiratómsstigi. Žetta er öfgafullt brot frį hugmyndinni um hlutlęgan veruleika eša žar sem nįttśrulögmįlin eiga sér sérstaka, platónska tilveru.

 

Ef ešlisfręšingurinn leitar aš ögn (notar agnaskynjara), žį finnst ögn. Ef ešlisfręšingurinn leitar aš bylgju (notar bylgjuskynjara) žį finnst bylgjumynstur. Skammtaeining hefur tvķžęttan möguleika, en raunverulegt (athugaš) ešli hennar er eitt eša annaš.

 

 

Skammtabylgjufall:

§  Tślkun bylgjupakka fyrir agnir žżšir aš žaš er ešlislęgur fuzziness śthlutaš žeim

§  Bylgjufalliš er stęršfręšilegt tęki til aš lżsa skammtaeindum

Bylgjuešli smįsjįrheimsins gerir hugmyndina um 'stöšu' erfitt fyrir subatomic agnir. Jafnvel bylgjupakki hefur einhvern 'fuzziness' ķ tengslum viš žaš. Rafeind į sporbraut hefur enga stöšu til aš tala um, ašra en hśn er einhvers stašar į sporbraut sinni.

Til aš takast į viš žetta vandamįl žróaši skammtafręšin verkfęri skammtabylgjufallsins sem  stęršfręšilega lżsingu į umgjöršum sem tengjast skammtaeiningu į tilteknu augnabliki.

 

 

§  bylgjufall tjį lķkur *žar til* męling er gerš

Lykilatrišiš ķ bylgjufallinu er aš stašsetning agna er ašeins gefin upp sem lķkur eša lķkur žar til męling er gerš. Til dęmis leišir žaš til stašsetningarmęlingar aš slį rafeind meš ljóseind og viš segjum aš bylgjufalliš hafi 'hruniš' (ž.e. bylgjuešli rafeindarinnar umbreytist ķ agnaešli).

 

 

Superposition:

§  skammtafręši er vķsindi um möguleika frekar en nįkvęmni Newtons ešlisfręši

§  Skammtahlutir og magn verša raunveruleg žegar athugaš er

§  Lykilsönnun į skammtayfirbyggingu er fyrirbęriš skammtagöng

 Hér lżsa žeir myndpunkti ķ heilmyndinni. jg

Here they describe an image point in the hologram. jg

 

Sś stašreynd aš skammtakerfi, svo sem rafeindir og róteindir, hafa óįkvešna žętti žżšir aš žau eru til sem möguleikar frekar en rauneiginleikar. Žetta gefur žeim žann eiginleika aš vera hlutir sem gętu veriš eša gętu gerst, frekar en hlutir sem eru. Žetta er ķ skörpri mótsögn viš ešlisfręši Newtons žar sem hlutirnir eru eša ekki, žaš er engin óvissa nema žau sem sett eru vegna lélegra gagna eša takmarkana į gagnaöflunarbśnašinum.

Frekari tilraunir sżndu aš raunveruleikinn į skammtafręšilegu (smįsjį) stigi samanstendur af tvenns konar veruleika, raunverulegum og möguleikum. Raunverulegt er žaš sem viš fįum žegar viš sjįum eša męlum skammtaeiningu, möguleikinn er įstandiš žar sem hluturinn var til įšur en hann var męldur. Nišurstašan er sś aš skammtaeining (ljóseind, rafeind, nifteind o.s.frv.) er til ķ mörgum möguleikum raunveruleika sem kallast superpositions.

Hęgt er aš sżna fram į yfirbyggingu mögulegra stašsetninga rafeindar meš athugušu fyrirbęri sem kallast skammtagöng.

 

 

§  Stašsetning rafeindarinnar, bylgjufallsins, er sannarlega dreifš, ekki óvķst

§  Athugun veldur žvķ aš bylgjufalliš fellur saman ķ raunverulegt

Takiš eftir aš eina skżringin į skammtagöngum er ef stašsetning rafeindarinnar er sannarlega dreifš, ekki bara falin eša ómęld. Žaš hrį óvissa gerir kleift aš bylgjuvirknin komist ķ gegnum hindrunina. Žetta er raunveruleg óįkvešni, ekki bara óžekkt magn fyrr en einhver męlir žaš.

Mikilvęgt er a taka tillit til ess a yfirfęrsla möguleika į kostum į sér ekki sta fyrr en einingin er sönnu . Žegar athugun hefur fariš fram (stašsetning er męld, massi įkvaršašur, hraši męldur) breytist yfirstašan ķ raun. Eša, į skammtamįli, segjum viš aš bylgjufalliš hafi hruniš.

 

 

§  Skammtatilvist er bundin umhverfinu, gagnstętt sjįlfstęši stórsęja hluta

Hrun bylgjufallsins viš athugun er umbreyting frį mörgum til žeirra, frį möguleika til raunveruleika. Sjįlfsmynd og tilvist skammtaeininga er bundin viš heildarumhverfi žess (žetta er kallaš samhengishyggja). Eins og einsheiti, orš sem fara eftir žvķ samhengi sem žau eru notuš ķ, breytir skammtaveruleikinn ešli sķnu ķ samręmi viš umhverfi sitt.

Ķ žeim stórsęja heimi sem stjórnaš er af klassķskri ešlisfręši eru hlutirnir eins og žeir eru. Ķ smįsjįrheiminum sem stjórnaš er af skammtaešlisfręši er tilvistarsamtal mešal agnanna, umhverfis hennar og žess sem rannsakar hana.

 

00000000000000000000000000 

vvv

1.1.1970 | 00:00

Ef ég mį ekki kynna žetta svona, žį tek ég žaš strax nišur.

Two-Slit Experiments (uoregon.edu) 

Žaš er betra aš horfa į slóšina hér nešan viš.

http://abyss.uoregon.edu/~js/21st_century_science/lectures/lec13.html 

 

Young Two-Slit Experiment:

 

Readings:

two slit experiment
Copenhagen Interpretation
Quantum Mechanics

 

§  tilraunin meš tveimur rifum er lykillinn aš žvķ aš skilja smįsjįrheiminn

§   

§  the two slit experiment is key to understand the microscopic world

Bylgjulķkir eiginleikar ljóss voru sżndir meš fręgri tilraun sem Thomas Young gerši fyrst snemma į nķtjįndu öld. Ķ upphaflegri tilraun lżsir punktljós upp tvęr mjóar ašliggjandi raufar į skjįnum og myndin af ljósinu sem fer ķ gegnum raufin sést į öšrum skjį. 

The wave-like properties of light were demonstrated by the famous experiment first performed by Thomas Young in the early nineteenth century. In original experiment, a point source of light illuminates two narrow adjacent slits in a screen, and the image of the light that passes through the slits is observed on a second screen.

 

 

 

click here to interference simulation

 

§  waves can interfere, for light this will make a series of light and dark bands

§  matter particles, such as electrons, also produce interference patterns due to their wave-like nature

§  so with a high flux of either photons or electrons, the characteristic interference pattern is visible

The dark and light regions are called interference fringes, the constructive and destructive interference of light waves. So the question is will matter also produce interference patterns. The answer is yes, tested by firing a stream of electrons.

 

 

 

§  if we lower the intensity of light, or the flux of electrons (the electric current), we should be able to see each photon strike the screen

§  each photon makes a dot on the screen, but where is the interference pattern?

However, notice that electrons do act as particles, as do photons. For example, they make a single strike on a cathode ray tube screen. So if we lower the number of electrons in the beam to, say, one per second. Does the interference pattern disappear?

 

 

 

§  the interference pattern is still there, it simply takes some time for enough photons, or electrons, to strike the screen to build up a recognizable pattern

§  interference, or a wave phenomenon, is still occurring even if we only let the photons, or electrons, through one at a time

§  so what are the individual particles interfering with? apparently, themselves

The answer is no, we do see the individual electrons (and photons) strike the screen, and with time the interference pattern builds up. Notice that with such a slow rate, each photon (or electron) is not interacting with other photons to produce the interference pattern. In fact, the photons are interacting with themselves, within their own wave packets to produce interference.

 

 

 

§  in order for a particle to interfere with itself, it must pass through both slits

§  this forces us to give up the common sense notion of location

But wait, what if we do this so slow that only one electron or one photon passes through the slits at a time, then what is interfering with what? i.e. there are not two waves to destructively and constructively interfere. It appears, in some strange way, that each photon or electron is interfering with itself. That its wave nature is interfering with its own wave (!).

The formation of the interference pattern requires the existence of two slits, but how can a single photon passing through one slit `know' about the existence of the other slit? We are stuck going back to thinking of each photon as a wave that hits both slits. Or we have to think of the photon as splitting and going through each slit separately (but how does the photon know a pair of slits is coming?). The only solution is to give up the idea of a photon or an electron having location. The location of a subatomic particle is not defined until it is observed (such as striking a screen).

 

 

Role of the Observer:

§  since the quantum world can not be observed directly, we are forced to use instruments as extensions of our senses

§  however, quantum entities are so small that even contact with one photon changes their position and momentum = measurement problem

§  1st hint that the observer is an important piece of any quantum experiment, can not isolate the observer or their effects

The quantum world can be not be perceived directly, but rather through the use of instruments. And, so, there is a problem with the fact that the act of measuring disturbs the energy and position of subatomic particles. This is called the measurement problem.

 

 

 

§  the two slit experiment is a good test of the role of the observer in the quantum realm

§  any experimental design that attempts to determine which slit a photon has passed through (test for its particle nature) destroys the interference pattern (its wavelike nature)

§  this is a breakdown of objective reality

§  each quantum entity has dual potential properties, which become an actual characteristic if and when it is observed

Thus, we begin to see a strong coupling of the properties of an quantum object and and the act of measuring those properties. The question of the reality of quantum properties remains unsolved. All quantum mechanical principles must reduce to Newtonian principles at the macroscopic level (there is a continuity between quantum and Newtonian mechanics).

How does the role of the observer effect the wave and particle nature of the quantum world? One test is to return to the two slit experiment and try to determine count which slit the photon goes through. If the photon is a particle, then it has to go through one or the other slit. Doing this experiment results in wiping out the interference pattern. The wave nature of the light is eliminated, only the particle nature remains and particles cannot make interference patterns. Clearly the two slit experiments, for the first time in physics, indicates that there is a much deeper relationship between the observer and the phenomenon, at least at the subatomic level. This is an extreme break from the idea of an objective reality or one where the laws of Nature have a special, Platonic existence.

 

If the physicist looks for a particle (uses particle detectors), then a particle is found. If the physicist looks for a wave (uses a wave detector), then a wave pattern is found. A quantum entity has a dual potential nature, but its actual (observed) nature is one or the other.

 

 

Quantum Wave Function:

§  a wave packet interpretation for particles means there is an intrinsic fuzziness assign to them

§  the wave function is the mathematical tool to describe quantum entities

The wave nature of the microscopic world makes the concept of `position' difficult for subatomic particles. Even a wave packet has some `fuzziness' associated with it. An electron in orbit has no position to speak of, other than it is somewhere in its orbit.

To deal with this problem, quantum physics developed the tool of the quantum wave function as a mathematical description of the superpositions associated with a quantum entity at any particular moment.

 

 

§  wave function express likelihood *until* a measurement is made

 

 

The key point to the wave function is that the position of a particle is only expressed as a likelihood or probability until a measurement is made. For example, striking an electron with a photon results in a position measurement and we say that the wave function has `collapsed' (i.e. the wave nature of the electron converted to a particle nature).

 

 

Superposition:

§  quantum physics is a science of possibilities rather than exactness of Newtonian physics

§  quantum objects and quantities becomes actual when observed

§  key proof of quantum superpositions is the phenomenon of quantum tunneling

 Hér lżsa žeir myndpunkti ķ heilmyndinni. jg

Here they describe an image point in the hologram. jg

The fact that quantum systems, such as electrons and protons, have indeterminate aspects means they exist as possibilities rather than actualities. This gives them the property of being things that might be or might happen, rather than things that are. This is in sharp contrast to Newtonian physics where things are or are not, there is no uncertainty except those imposed by poor data or limitations of the data gathering equipment.

Further experimentation showed that reality at the quantum (microscopic) level consists of two kinds of reality, actual and potential. The actual is what we get when we see or measure a quantum entity, the potential is the state in which the object existed before it was measured. The result is that a quantum entity (a photon, electron, neutron, etc) exists in multiple possibilities of realities known as superpositions.

The superposition of possible positions for an electron can be demonstrated by the observed phenomenon called quantum tunneling.

 

 

§  the position of the electron, the wave function, is truly spread out, not uncertain

§  observation causes the wave function to collapse to an actual

Notice that the only explanation for quantum tunneling is if the position of the electron is truly spread out, not just hidden or unmeasured. It raw uncertainty allows for the wave function to penetrate the barrier. This is genuine indeterminism, not simply an unknown quantity until someone measures it.

It is important to note that the superposition of possibilities only occurs before the entity is observed. Once an observation is made (a position is measured, a mass is determined, a velocity is detected) then the superposition converts to an actual. Or, in quantum language, we say the wave function has collapsed.

 

 

§  quantum existence is tied to the environment, opposite to the independence of macroscopic objects

The collapse of the wave function by observation is a transition from the many to the one, from possibility to actuality. The identity and existence of a quantum entities are bound up with its overall environment (this is called contextualism). Like homonyms, words that depend on the context in which they are used, quantum reality shifts its nature according to its surroundings.

In the macroscopic world ruled by classical physics, things are what they are. In the microscopic world ruled by quantum physics, there is an existential dialogue among the particle, its surroundings and the person studying it.

 


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