Ask a physicist anything. (8)

[Loudmouth]

That is a though experiment that leads down a dead end road. There is no such thing as a particle capable of being in two states simultaneously until it is observed. It is one or the other, always has been, you just observe it in one of the possible states at any given time.

Evidence?

 

[Justatruthseeker]

Evidence?

Where is your evidence that it is in two states simultaneously until observed? Not theory, evidence.

My evidence is that you only ever observe it in one state, not both, not in a transitional phase, but one and one state only.

 

[Subduction Zone]

Where is your evidence that it is in two states simultaneously until observed? Not theory, evidence.

My evidence is that you only ever observe it in one state, not both, not in a transitional phase, but one and one state only.

.

The evidence is the double slit interference experiments of one electron at a time. The electrons interfere with themselves by going through "both slots" at the same time.

Even larger objects can do this:


Pushing The Boundaries Of Quantum Reality : 13.7: Cosmos And Culture : NPR

Now, what is your evidence to the contrary?

 

[Wiccan_Child]

That is a though experiment that leads down a dead end road. There is no such thing as a particle capable of being in two states simultaneously until it is observed. It is one or the other, always has been, you just observe it in one of the possible states at any given time. Just as two objects on set courses and velocities will ALWAYS interact in one predictable outcome. Such are the laws of physics.

Such are the laws of CLASSICAL physics, which fails spectacularly to predict how atomic and subatomic particles behave. Enter quantum mechanics, which successfully explains to absurd degrees of accuracy the behaviour of such particles. One of the implications of the theory is superposition and wavefunction collapse.

Two billard balls colliding will always react in one, and only one course of action, depending on their velocities and angles of interaction. Once speed and angle is set, there can be but one outcome. Don't go down the dead end road of particles being in different states simultaneously, that is simply sciences cop-out for not understanding all the variables involved.

You might have had a good chance at selling classical determinism in the late 1800s, but we're quite far down the quantum road now. Technology is based on quantum ideas, we're teleporting systems of particles and even energy, and we're building quantum computing based on superposition. Classical mechanics is so long dead is antique.

The ultimate goal of science is to simplify the natural world, not complicate it with theories that in reality explain nothing at all.

BS.

The ultimate goal of science is the truth. If the truth is complicated, so be it. We will not simplify just for the sake of it.

But being tenor-ship requires a set amount of published papers, papers are written that have nothing to do with reality that creep into dogmatic belief.

You seem to be unaware of that core facet of science: FALSIFIABILITY. Papers published replicable results. If the paper has nothing to do with reality, it would be exposed as such as soon as another scientist tried to replicate the results.

In reality we simply lack the technology and knowledge to account for all the unseen variables, so we hedge our bets and describe it in both states, so one or the other is always true, and observation seems to back theory. But it only hides a flaw in the underlying theories themselves.

This simply belies your severely naive understanding of quantum mechanics. Uncertainty principles and superposition aren't mere technological limitations, they're necessary consequences of the theory.

Just as if you believe in resonance, that an electron here will resonate instantly with an electron on the other side of the universe, then you are propagating belief in a force capable of FTL interaction. And if that is true, then it is also possible for gravity to be an instantaneous action at a distance force. Declared impossible, so by extension, so is resonance. It can not be both ways.

A particle is in one state or another at the time of observation, not both states simultaneously until observed. It may take another 100 years before we are capable of understanding all the variables involved, but we should not propagate incorrect theories simply because that would leave us without an explanation, but should instead search for one. Better to have no theory, than to continue with an incorrect one.

Except you have no evidence the theory is incorrect. As it stands, QM is superb at predicting subatomic behaviour. Reality doesn't give a flying whoop whether this upsets your sensibilities - if particles exist in superpositions, then so be it. The evidence overwhelmingly supports QM, so QM is where we go.

 

[Wiccan_Child]

Where is your evidence that it is in two states simultaneously until observed? Not theory, evidence.

My evidence is that you only ever observe it in one state, not both, not in a transitional phase, but one and one state only.

Don't dodge the question - you made a claim, put up the evidence.

QM has been substantiated since the early 1900s. You can pick up a child's textbook and see for yourself. If QM implies superpositions, and the evidence supports QM, then superpositions enjoys all the evidence of QM. This is basic logic.

 

[Cactus Jack]

Explain to me the theory of Fluid Dynamics. I'm not a dummy when it comes to electronics, but this one is a stumper for me.

 

[Justatruthseeker]

.

The evidence is the double slit interference experiments of one electron at a time. The electrons interfere with themselves by going through "both slots" at the same time.

Even larger objects can do this:


Pushing The Boundaries Of Quantum Reality : 13.7: Cosmos And Culture : NPR

Now, what is your evidence to the contrary?

And the slit experiment proved the wave theory, not the photon theory of light.

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."


Once again, you are trying to use an experiment that proves the wave theory of light, to attempt to prove the particulate theory of light. The phenomenon is completely explained by the wave theory.

I am not saying photons do not exist, merely that you can not use an experiment that proves the wave theory to now attempt to prove the particle theory. Nor one that has explanation in the wave theory that is twisted to try to prove the particle theory.

Nor can you tell me technology is advanced enough to detect a single photon, despite their claims. We can't even image an electron, but as a mere cloud, and you want me to believe we can faithfully detect even smaller particles with complete accuracy? Hogwash!

 

[essentialsaltes]

Nor can you tell me technology is advanced enough to detect a single photon

Yes, we can.

Photomultiplier

"These detectors multiply the current produced by incident light by as much as 100 million times (i.e., 160 dB), in multiple dynode stages, enabling (for example) individual photons to be detected "

 

[AV1611VET]

As I understand it, the speed of light can be slowed down.

Question:

When a beam of light goes through a translucent object ... and slows down ... does it then speed back up after it emerges from that object?

 

[essentialsaltes]

As I understand it, the speed of light can be slowed down.

Question:

When a beam of light goes through a translucent object ... and slows down ... does it then speed back up after it emerges from that object?

Yes it does. When we talk about c, the speed of light, that's the speed of light in vacuum, a constant. In any particular medium, light travels at the speed of light in that medium. For common materials, the speed of light in that medium is c divided by the index of refraction. So vacuum would be like an index of refraction of exactly 1. Air slows down light a little. The index of refraction of air is 1.0003.

In water, it's 1.33, so light travels at a speed of only about 75% of c in water. Glass varies, but is around 1.5. Diamond has an index of refraction of 2.42, so light travels at less than half of c in diamonds.

So light going from air into glass slows down, and when it comes back into air, it speeds up.

 

[essentialsaltes]

PS The animation here shows how a change in speed of the wave as it passes from one medium to another causes the light to bend, i.e. refract. This is why it's called the index of refraction.

 

[AV1611VET]

PS The animation here shows how a change in speed of the wave as it passes from one medium to another causes the light to bend, i.e. refract. This is why it's called the index of refraction.

Thank you, sir!

 

[Tinker Grey]

Yes it does. When we talk about c, the speed of light, that's the speed of light in vacuum, a constant. In any particular medium, light travels at the speed of light in that medium. For common materials, the speed of light in that medium is c divided by the index of refraction. So vacuum would be like an index of refraction of exactly 1. Air slows down light a little. The index of refraction of air is 1.0003.

In water, it's 1.33, so light travels at a speed of only about 75% of c in water. Glass varies, but is around 1.5. Diamond has an index of refraction of 2.42, so light travels at less than half of c in diamonds.

So light going from air into glass slows down, and when it comes back into air, it speeds up.

How does it speed back up? Does it acquire energy, or does it have something to do with a fundamental property? Or something else?

 

[Subduction Zone]

And the slit experiment proved the wave theory, not the photon theory of light.

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."


Once again, you are trying to use an experiment that proves the wave theory of light, to attempt to prove the particulate theory of light. The phenomenon is completely explained by the wave theory.

I am not saying photons do not exist, merely that you can not use an experiment that proves the wave theory to now attempt to prove the particle theory. Nor one that has explanation in the wave theory that is twisted to try to prove the particle theory.

Nor can you tell me technology is advanced enough to detect a single photon, despite their claims. We can't even image an electron, but as a mere cloud, and you want me to believe we can faithfully detect even smaller particles with complete accuracy? Hogwash!

My point totally went over your head. The link I provided showed that not only electrons can be in "two places at once". How do you explains electrons interfering with themselves in regards to the double slit experiment? It is no problem to send one electron at a time through a double slit, why do you think that it interferes with itself?

The point is that particles are not purely particles, waves are not purely waves. Physics uses the tools that are available to it. If "reality" does not agree with experiment then "reality" is usually wrong. Physicists treat objects like particles when it is useful to treat them that way and as waves when that is the useful manner. Reality does not care what physicists claim.

 

[essentialsaltes]

How does it speed back up? Does it acquire energy, or does it have something to do with a fundamental property? Or something else?

It doesn't acquire energy. It's more that when light goes through some medium, the matter in the medium reaches out grabby hands that slow down the photon passing through it. But when the grabby hands go away, the photon can go back to its previous speed.

 

[Wiccan_Child]

How does it speed back up? Does it acquire energy, or does it have something to do with a fundamental property? Or something else?

Light never slows down - it always travels at c. The snag is that it seems to slow down because, when it travels through a medium like glass, it has to navigate all the atoms, bouncing off them like a pinball. Though it travels a straight line on average, its actual path is longer, which makes it look like it's taking longer to travel.

It's like a truck driving from Scotland to Germany. We know the distance (as the crow flies), we know how long it took, divide one by the other, and we get speed - say, 30 mph. But the truck's speedometer records a constant 50 mph. Why? Because it didn't travel in a straight line - it meandered all over the place to follow the roads.

 

[Justatruthseeker]

Yes, we can.

Photomultiplier

"These detectors multiply the current produced by incident light by as much as 100 million times (i.e., 160 dB), in multiple dynode stages, enabling (for example) individual photons to be detected "

So you want to use a vacuum plasma tube to explain photons, but then ignore plasma in the universe in favor of Fairie Dust?

And you forgot to add "when the incident flux of light is very low."

So when the flow of light through the device is low, you can measure individual photons? It amplifies the current produced by incident light, yet incident light is not used in slit tests, but direct beams. Beams where the incident flux of light is not very low.

"Incident photons strike the photocathode material, which is present as a thin deposit on the entry window of the device, with electrons being produced as a consequence of the photoelectric effect."

You can not rule out the secondary refraction pattern as being caused by these electrons, which themselves emit EM radiation, i.e. photons. Also every material in existence is constantly emitting EM fields, which you claim to be mediated by photons. So now you want me to believe that a device made of material that emits photons constantly, one can be singled out from all those produced, as being the one originally produced. I got news for you. Even when the device is turned off, it is emitting EM radiation, as if everything around you including you.

 

[AV1611VET]

Light never slows down - it always travels at c. The snag is that it seems to slow down because, when it travels through a medium like glass, it has to navigate all the atoms, bouncing off them like a pinball. Though it travels a straight line on average, its actual path is longer, which makes it look like it's taking longer to travel.

It's like a truck driving from Scotland to Germany. We know the distance (as the crow flies), we know how long it took, divide one by the other, and we get speed - say, 30 mph. But the truck's speedometer records a constant 50 mph. Why? Because it didn't travel in a straight line - it meandered all over the place to follow the roads.

Then what breaks it up into the colors of the rainbow?

 

[Wiccan_Child]

Then what breaks it up into the colors of the rainbow?

Diffraction. When light comes from the Sun, not all the photons have the same energy; some are red, some are green, etc. To our eyes, this is perceived as 'white'. But when rainbows are formed, the light does a U-turn inside the water droplets, and higher-energy light does a tighter U-turn. This means they go in as one, but come out at different angles, because light of different energy is diffracted harder or weaker.

But that's just one drop, so it's a little harder to imagine why this forms the coherent object in the sky - the rainbow. The reason this happens is that only those photons leaving the raindrop at the right angle hit our eye:

If you can imagine it, it's like a laser beam of white light coming from the Sun, hitting the sheet of rain, and being sent back the other way, splaying out in a sort of cone. Because of the horizon, we only see the upper half -the bow. In an airplane, pilots report seeing the full thing.

The sheet of rain reflects the sunlight back into your eyes, but it's diffracted, making it rainbow-y.

 

[essentialsaltes]

So when the flow of light through the device is low, you can measure individual photons?

Yes, when the intensity of light is high, there are too many photons to count them individually.