# Bell's circuit beginner's question: Sampling alters, - what's normal?

• I
• ndvcxk123
In summary: I'm sure there are some good "introduction to quantum mechanics" sites around as well.In summary, the conversation discusses the concept of normality in relation to observing unsplit photon spin and the possibility of split photons having different probability outcomes. The speaker is seeking clarification on how normal outcomes can be determined without sampling and acknowledges their lack of familiarity with bra-ket notation. The responder suggests using more common terminology and resources to better understand the topic.
ndvcxk123
TL;DR Summary
Sampling one of the two split photons results in probability alteration toward spin of entangled photon, ok, but how can normal outcome be determined w.o. sampling ?
Yes, I should hit the books more, so forgive the basic question. I take it normality is known by observing unsplit photon spin ? But how can one then exclude that split photons in themselves might have different probability outcomes ? Thx much in advance. (Please pardon that only moderately-talented people outside physics cannot quickly learn bra-ket notation...)

I've no clue what you are talking about. You should clearly describe your problem. Maybe you then even get a clue about the answer yourself!

ndvcxk123, DrChinese and Demystifier
ndvcxk123 said:
Summary: Sampling one of the two split photons results in probability alteration toward spin of entangled photon, ok, but how can normal outcome be determined w.o. sampling ?

Yes, I should hit the books more, so forgive the basic question. I take it normality is known by observing unsplit photon spin ? But how can one then exclude that split photons in themselves might have different probability outcomes ? Thx much in advance. (Please pardon that only moderately-talented people outside physics cannot quickly learn bra-ket notation...)
Just to add to vanhees71's comment: you are using lingo that is not common, and therefore we can't understand your question.

Parametric down conversion (PDC or SPDC) can split a photon into a system of 2 entangled photons. We usually just talk about the system of 2 entangled photons rather than discussing how they became entangled (since there are a number of other ways to create entanglement). I am guessing you want to talk about entanglement, and not parametric down conversion (which is actually a completely different topic).

I don't know what you mean by "probability alteration" or "normal outcome without sampling" as these phrases are unique to you. Bell tests on entangled photon pairs produce statistical results which match the predictions of quantum mechanics (specifically the percentage of matches - HH or VV - relative to the angles the photons' polarization is measured). Phrases such as "normality" and "unsplit photon spin" are likewise unique to you.

If you could reformulate your questions in more common terminology, we could attempt to answer. You might try reading some existing PF threads to get a better idea of phrasing, or perhaps a few Wikipedia articles.

ndvcxk123 and vanhees71

## 1. What is Bell's circuit and how does it work?

Bell's circuit is a simple electronic circuit that consists of a battery, a resistor, and a light bulb. When the circuit is closed, the battery provides a flow of electrons through the resistor, which creates heat and causes the light bulb to light up.

## 2. How does sampling alter Bell's circuit?

Sampling alters Bell's circuit by interrupting the flow of electrons from the battery to the light bulb. This can be done by using a switch or by physically disconnecting and reconnecting the circuit. When the circuit is interrupted, the light bulb will turn off until the circuit is closed again.

## 3. Why is sampling important in Bell's circuit?

Sampling is important in Bell's circuit because it allows us to control the flow of electricity and the behavior of the circuit. By interrupting the circuit, we can turn the light bulb on and off, which is the basic principle behind many electronic devices.

## 4. How does sampling affect the normal functioning of Bell's circuit?

Sampling does not affect the normal functioning of Bell's circuit in a significant way. As long as the circuit is closed, the battery will continue to provide a flow of electrons through the resistor and the light bulb will continue to light up. Sampling only interrupts this flow temporarily.

## 5. Are there any risks associated with sampling in Bell's circuit?

Sampling in Bell's circuit does not pose any significant risks as long as the circuit is properly designed and the voltage and current levels are within safe limits. However, it is important to always handle electronic circuits with caution to avoid electric shocks or other accidents.