Photons

[TillICollapse]

"...something can be both "yes" and "no" at the same time."

"...things often are "yes" and "no" and "both" and "neither", all at the same time."

I'm not alone here. The famous quantum physicist Roger Penrose said in an interview a few years back (and I'm summarizing here): "There has to be something wrong with QM, because science is supposed to explain things which are logical and acceptable to the human mind, and QM doesn't do it." You know, there's also those quotes by physicists which go something like "if you think you understand QM, you don't understand QM".

Feynman on understanding quantum mechanics - YouTube

Yes, I know it's testable and observable, and some of our modern technologies operate reliably using QM concepts. But that doesn't mean it's not really funky. Then again I believe in a Triune God who is three persons in one, and a lot of people consider that mysterious, inexplicable and funky.

When we start talking "spooky action at a distance", that's when things get funky lol So it's not just Penrose, it's Penrose and company lol.

And you went and played the Feynman card. Since we are throwing quotes around, I'll throw out one more ... one of my all time favorites, and it's from Feynmen ... almost makes me want to fall in love and study physics while the romance is flowing lol:

"I am going to tell you what nature behaves like. If you will simply admit that maybe she does behave like this, you will find her a delightful, entrancing thing."

-- Richard Feynman

 

[Chesterton]

"I am going to tell you what nature behaves like. If you will simply admit that maybe she does behave like this, you will find her a delightful, entrancing thing."

-- Richard Feynman

Interesting that he used the word "maybe" in there. But I concur that it's a fine quote. Nature is a lot of things: delightful, entrancing, beautiful, ugly, wild, dangerous, etc. Not unlike a woman, although I have to add that she's our Sister, not our Mother.

 

[essentialsaltes]

"But an ace can't be dealt to anyone at any time."

Why do say that?
...
It seems to me the location is fixed, by law, before the shuffle, during the shuffle and after the shuffle. There's nothing "variable" about it.

Correct, the locations of the aces are fixed. If the first ace in the deck is the second card, and you are sitting in the first chair (and will receive the top card), then you cannot be dealt the ace. You don't know that, because the information about the locations of the aces is hidden from you. You may believe you can be dealt an ace at any time, but this is false, since the locations are fixed. You cannot be dealt an ace as your first card.

 

[Chesterton]

Correct, the locations of the aces are fixed. If the first ace in the deck is the second card, and you are sitting in the first chair (and will receive the top card), then you cannot be dealt the ace. You don't know that, because the information about the locations of the aces is hidden from you. You may believe you can be dealt an ace at any time, but this is false, since the locations are fixed. You cannot be dealt an ace as your first card.

Merely not knowing where the ace is seems a very different type of "uncertainty". I may not be following you, but it seems you're saying something like the uncertainty principle really just means all things really are determined by fixed laws, and are potentially predictable, but we just can't see them (at least not yet). That's not what I've heard about it.

 

[essentialsaltes]

Merely not knowing where the ace is seems a very different type of "uncertainty". I may not be following you, but it seems you're saying something like the uncertainty principle really just means all things really are determined by fixed laws, and are potentially predictable, but we just can't see them (at least not yet). That's not what I've heard about it.

Sigh. Yes, you are correct. I perhaps made a mistake with my analogy of a real casino, and then also describing a quantum casino.

"For quantum randomness, the locations are not fixed in the shuffle. Any card really can be the ace."

 

[RealityCheck]

Sigh. Yes, you are correct. I perhaps made a mistake with my analogy of a real casino, and then also describing a quantum casino.

"For quantum randomness, the locations are not fixed in the shuffle. Any card really can be the ace."

Even with a quantum casino, there are a finite number of possible outcomes.

 

[TillICollapse]

Even with a quantum casino, there are a finite number of possible outcomes.

Only when you collapse the wave function, or consider the most probable positions. Until then, there are an infinite number of possible positions an ace could be in (since it could be outside of the deck, outside of the casino, etc), yes ?

 

[Justatruthseeker]

Correct, the locations of the aces are fixed. If the first ace in the deck is the second card, and you are sitting in the first chair (and will receive the top card), then you cannot be dealt the ace. You don't know that, because the information about the locations of the aces is hidden from you. You may believe you can be dealt an ace at any time, but this is false, since the locations are fixed. You cannot be dealt an ace as your first card.

That is not a wholly valid argument, because in reality you can not assume the deck has already been shuffled, and even after it has you nor anyone can know the location of the ace. Without first looking through the deck and discerning their locations, the probability that the ace is the first, second or whatever card is just as valid as for any other location within the deck. Only if you already know the answer, which means their is no chance involved, can you make such a claim. Until that first card is turned, the probability is just as valid for it being an ace as it is for any other card, unless you already know the results, in which case there is no probability to begin with.

 

[TillICollapse]

That is not a wholly valid argument, because in reality you can not assume the deck has already been shuffled, and even after it has you nor anyone can know the location of the ace. Without first looking through the deck and discerning their locations, the probability that the ace is the first, second or whatever card is just as valid as for any other location within the deck. Only if you already know the answer, which means their is no chance involved, can you make such a claim. Until that first card is turned, the probability is just as valid for it being an ace as it is for any other card, unless you already know the results, in which case there is no probability to begin with.

I think the deck of cards analogy isn't the greatest because it's talking about classical probabilities verses quantum probabilities. Not being shown the deck and thus not knowing where the ace is, isn't the same as not measuring the position and momentum of a particle. The ace is still SOMEWHERE in that deck, not in superposition.

 

[Justatruthseeker]

Even with a quantum casino, there are a finite number of possible outcomes.

Correct, even in quantum dynamics the probability is limited by the influences with other quantum fluxes.

To bring an analogy a particle will always travel in a straight line, unless and until it encounters another particle, or the influence of another body. Even then its course is already set, depending on the course and speed of both particles. Two objects encountering one another on set velocities and angles of interaction, have only one possible outcome. There is no what if's involved.

 

[sfs]

To bring an analogy a particle will always travel in a straight line, unless and until it encounters another particle, or the influence of another body. Even then its course is already set, depending on the course and speed of both particles. Two objects encountering one another on set velocities and angles of interaction, have only one possible outcome. There is no what if's involved.

Incorrect. Two subatomic particles that scatter off one another do not have a single possible outcome.

 

[RealityCheck]

Only when you collapse the wave function, or consider the most probable positions. Until then, there are an infinite number of possible positions an ace could be in (since it could be outside of the deck, outside of the casino, etc), yes ?

No. There are still a finite number of solutions to quantum probability waves. It's possible there are *a lot* of solutions, but they are finite and discrete. This was the incredible contribution of Planck, after whom the Planck constant is named - there is not an infinite spectrum of possible solutions, but a finite set of discrete solutions.

And in any case, what you're describing with the Ace being outside the deck is equivalent to an electron that is not bound to a nucleus - i.e., it's no longer part of that system. The number of solutions to where an electron may be located within an atom presumes the electron is actually part of the atomic system - if it's not, then you're dealing with a completely different problem altogether. Likewise, the number of solutions to what card might be an ace in a quantum deck presumes that the aces are bound to the deck, regardless of where in the deck or how many there might be.

And of course, no two aces or for that matter no two cards can be in the same state within the deck - that is the same position in the deck cannot hold two different cards at the same time. Same as the Pauli Exclusion Principle for Fermions.

 

[sfs]

No. There are still a finite number of solutions to quantum probability waves. It's possible there are *a lot* of solutions, but they are finite and discrete. This was the incredible contribution of Planck, after whom the Planck constant is named - there is not an infinite spectrum of possible solutions, but a finite set of discrete solutions.

Whether the number of solutions to a QM problem is infinite or finite depends on the problem and the question you're asking. The energy change to an atom when it absorbs a photon has discrete values for example, but only if the atom does not become ionized in the process.

 

[juvenissun]

From what I understand, the science isn't clear on whether photons are particles or waves, because they seem to have characteristics of both.

When light lands on a physical object, some of it's reflected and some of it's absorbed (and in the case of transparent material like glass or water, most of it just passes through).

My question is: what's happening on the level of the individual photon? Are some of them (if they are particles) bouncing off things, and some of them absorbed, or are a percentage of them (if they are waves) doing the same? Can we determine the percentage?

If I can see a rock in my backyard, it's because the photons are bouncing off of it and striking my eyeballs. But on a hot summer day, I can also touch the the rock and feel warmth because of those same photons.

Let's say there were 10 million photons hit a surface. ...
Would that solve your problem?

 

[Loudmouth]

Correct, even in quantum dynamics the probability is limited by the influences with other quantum fluxes.

To bring an analogy a particle will always travel in a straight line, unless and until it encounters another particle, or the influence of another body. Even then its course is already set, depending on the course and speed of both particles. Two objects encountering one another on set velocities and angles of interaction, have only one possible outcome. There is no what if's involved.

How do you explain the results of Young's double slit experiment? What causes a photon to hit one spot, and the next photon to hit another spot?

Double-slit experiment - Wikipedia, the free encyclopedia

 

[Justatruthseeker]

How do you explain the results of Young's double slit experiment? What causes a photon to hit one spot, and the next photon to hit another spot?

Double-slit experiment - Wikipedia, the free encyclopedia

I don't think we really have the technology to count a single photon. We can't even image an electron, but as a cloud, and you expect me to believe we are capable of separating what must be a continuous stream of billions of photons?

This was done at the beginning of the 19th century, when technology was in its infancy. The results of the test backs up the "wave theory of light", not the particle theory of light, as you seem to want to apply it to.

Young's interference experiment - Wikipedia, the free encyclopedia

"After that, the corpuscular theory of light was vanquished, not to be heard of again till the 20th century. Arago later noted that the phenomenon (which was later to be known as the Arago spot) had already been observed by Joseph-Nicolas Delisle[1][7] and Giacomo F. Maraldi[8] a century earlier."

Current theory has decided it backs up both particle and wave theory, but not so, Young's results are clear that only the wave theory of light is supported by his experiment.

So you want to use a theory that supports the wave theory of light in an attempt to support a particle theory and interpretation??????????

 

[Chesterton]

How do you explain the results of Young's double slit experiment? What causes a photon to hit one spot, and the next photon to hit another spot?

God has a sense of humor. He loves to control small particles in order to mess with physicists.

 

[Loudmouth]

I don't think we really have the technology to count a single photon.

Yeah, we do. It produces the same interference pattern.

Interference - Young's experiment with single photons: Physclips - Light

Current theory has decided it backs up both particle and wave theory, but not so, Young's results are clear that only the wave theory of light is supported by his experiment.

Then how do you explain the particle-like detections that are points?

Added by edit: In the single photon experiment above, they use a PMT. The PMT detects photons using the photoelectric effect, the classic example of the particle-like nature of photons. So we have both the wave-like and particle-like characteristics of photons in a single experiment.

 

[leftrightleftrightleft]

There are so many analogies about randomness and probability being thrown around here and I think what is confusing some people is the difference between "what will be" and "what is".

Chesteron, in the shuffled deck analogy, are you wanting to know "whether an ace will be pulled" or "where the aces are in the deck"?

Those are two fundamentally different questions.

The first question involves probability (and is thus temporal). You could state that there is a 1/13 chance of pulling an ace but you will never know for certain until after the card is picked. The answer depends on time. It depends on a before and after (before the card is drawn and after the card is drawn).

The second question does not involve probability (and is atemporal). This is the equivalent of flipping over the deck and looking for the position of the aces. It doesn't depend on time or future events, it is purely a description of what is.


The strangeness of quantum mechanics (and relativity) is that there is no description of "what is" at some point in time. So the answer to the second question does not apply. If you want an answer to the first question that goes beyond "a chance of 1/13 of drawing an ace", then you need a time machine

That's the way I see it, I'm not a quantum physicist though

 

[TillICollapse]

No. There are still a finite number of solutions to quantum probability waves. It's possible there are *a lot* of solutions, but they are finite and discrete. This was the incredible contribution of Planck, after whom the Planck constant is named - there is not an infinite spectrum of possible solutions, but a finite set of discrete solutions.

And in any case, what you're describing with the Ace being outside the deck is equivalent to an electron that is not bound to a nucleus - i.e., it's no longer part of that system. The number of solutions to where an electron may be located within an atom presumes the electron is actually part of the atomic system - if it's not, then you're dealing with a completely different problem altogether. Likewise, the number of solutions to what card might be an ace in a quantum deck presumes that the aces are bound to the deck, regardless of where in the deck or how many there might be.

And of course, no two aces or for that matter no two cards can be in the same state within the deck - that is the same position in the deck cannot hold two different cards at the same time. Same as the Pauli Exclusion Principle for Fermions.

This is why I don't like the casino/deck analogy ... I was talking about an ace, independent of the deck and casino unfortunately. Doing away with the analogies, I was talking about a single electron, for example, before being measured.