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video or some proof of basic double split experiment?

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flyboy

Rising Star
Is there somewhere we can see the experience of the supposed paradox of the double split experiment, or are we supposed to take the physicists' word for it? Is there some 'quantum experiment' we can run ourselves?!

Finally, how strong a microscope does one need to see a basic molecule? An atom? Is it all just lenses or is there some greater technology involved that allows one to seomething so small? Is this called an atomic microscope or did i just make up that word?
 
Here's a youtube video of an interference pattern being generated via a double slit. There's no need to be skeptical, the phenomenon is very real. Typically you get shown a demonstration of the experiment as an undergrad at university, which is where I've seen this done.

We have no microscopes capable of seeing small molecules or atoms. You'd need to magnify it to about x10^8 to be able to observe an atom through a microscope. What you're probably thinking of is an electron microscope. Even an electron microscope can only magnify by about 2x10^6, still not large enough to see atoms or small molecules. The only way we can get a look at atoms and molecules is when they're in a regular repeating array (a crystal); in that case we can probe them with x-ray crystallography, which lets us create a 3D image of electron density in the crystal through a process called a Fourier transform.
 
...or by using nuclear magnetic resonance (NMR) in which case a more "dynamic" state of the molecules can be obtained. The electron density clouds from X-ray crystallography are notoriously "static", just as things tend to be inside the crystal structure. NMR solves the structure of atome in solution which is fairly handy at giving an idea about the intramolecular motion of the molecules.

But both X-ray and NMR can give resolutions of around 2 Angstrom (=0.2nanometers) at best. Still nowhere close to even observing the behavior of single electrons.
 
I saw a 5 million x miscroscope in use on some wood, hair, skin etc. on a youtube stlye site but that begs the questions of course if we can get to 5 million why can we not get to 50 million or 1 billion. I mean, if telescopes can see the edge of the universe.... how many time does hubble multiply the zoom?
 
Of course it is feasible, we just do not have the technology. It is all a matter of developing instruments with better resolution.

Resolution in practice means to be able to resolve between different objects that would otherwise look like one. For instance, a piece of dust can look like a single piece to our eyes, but it may appear as a composite of 2-3 smaller pieced when watched using magnifying lenses. The resolution of an instrument is dependent on the medium it uses.

The standard optical microscopes uses light and under the most ideal conditions resolves objects that are up to 500-600nm (average wavelength of visible light) apart. In practice, since the optical lenses of a microscope are not ideal, we never get such a good resolution.

Electron microscopes use electrons as the medium and uneven magnetic fields as "lenses". Thus, in theory they can resolve objects of up to 1 electron in size, but since lenses are (and will always be) imperfect the best possible resolution is 1000x worse.

Maybe if one devises microscopes that use subatomic particles as the medium? then we yould be able to "see" even smaller objects, but for the moment this is science fiction.
 
A few questions hit me while falling asleep last night:

1) in the case of the "observer", i guess this is a basic electron detector. But does the interference pattern dissapear if the detector is in place, but not powered "on"? What about if the detector is deffective, say a few random chips were damaged.. so it's on and trying to detect but does not have the ability to give an accurate reading?

2) can we do an experiment at home with a flashlight or $10 handheld lazer or anything not a million dollars that might at least hint at the duality of light?

3) What exactly is a "quanta", is that a unit of measurement, ie the smallest possible variation of position?

4) OK, so the double slit demonstrates something weird about the nature of matter, has anyone proposed it's relation or relevence to the nature of time?

5) Why can almost everything in the world be split in half at some angle in order to become two almost identical units? From splitting myself down the middle, to a fruit, to a car, to a chicken, to an ipod, to a pc, to a chair.... everything is balanced. I know it's unrelated and probably best asked of the almighty, but does anyone propose why this is?

Bonus Question:

Why am i more interested in this than the job my boss is paying me to be doing right now? :lol:
 
1.) No, an observer is not an electron detector. It's simply anything which interacts with an electron, necessitating that it be in a specific location, not just a probabalistic cloud. This has to do with the schoedingers cat thing, and the resolution of the wavefunction into eigenvalues. It's not involved in the double slit phenomenon. The double slit phenomenon is a result of the wave nature of light.

2.) You can do this with any coherant light source (wikipedia defines coherance w/ respect to light here)

3.)You defined it. A quanta is the smallest possible unit of change. Prior to quantum mechanics, it was assumed that there was no smallest unit of change in position of an electron (ie that the change was continuous along any given axis)

Edit: Motion isn't the only thing that's quatized though; energy levels are too. Statistical mechanics was unable to accurately describe black-body radiation (the color of light emitted by very hot objects, like the glowing of a superheated cast-iron stove) because it treated energy levels as continuous. Einstein realized that the way to resolve this paradox was by treating energy levels as quantized.

4.) Nothing "weird" about it exactly. Light has both a wave nature and a particle nature to it, known as "wave-particle duality". J.J. Thomson's experiments with the photoelectric effect demonstrated its particle nature. The double slit experiment demonstrates its wave nature.

5.) 🤷 Developemental genes for radial symmetry are conserved from early evolution, until they were usurped in the case of higher animals by planar symmetry?
 
flyboy said:
5) Why can almost everything in the world be split in half at some angle in order to become two almost identical units? From splitting myself down the middle, to a fruit, to a car, to a chicken, to an ipod, to a pc, to a chair.... everything is balanced. I know it's unrelated and probably best asked of the almighty, but does anyone propose why this is?
Click to expand...

One of my favorite questions. All of the objects you name have bilateral symmetry. One side is a mirror reflection of the other. Man-made objects look like this because people find them more pleasant looking and they sell better.

Bilateral symmetry in critters is a profoundly awesome question though. It has to do with embryonic development and information. It is simple at the highest level of consideration. When an animal is developing is must map out where it's organs and appendages will be. A simple way to do this is by establishing two axis: a head to tail axis and a front to back axis. All animals do this. Even starfish that appear radially symmetric start out as bilateral embryos.

Here's the kicker: The same genes produce this map of the early embryo in all animals! This blows my mind almost once a week. Later in development a third left-right axis forms that coordinates placement of your internal organs. Flies and worms may lack this axis. So we are, in a very real sense, more three-dimensional than flies and worms.
 
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