Question re photons/EM waves and the double slit experiment

In summary, the conversation discussed the concept of electromagnetic waves and their behavior as both particles and waves. The difficulty in detecting and studying these waves at different frequencies was also mentioned. The question was posed whether all EM frequencies in the spectrum exhibit interference patterns as seen in the famous slit experiment with photons. It was noted that not only EM waves, but also massive particles exhibit such interference patterns. The possibility of conducting experiments with different frequencies to demonstrate this effect was also mentioned. Additionally, the conversation touched on the interaction of photons with atomic nuclei and the use of interference in technologies such as phased array antennas and aperture synthesis in radio astronomy.
  • #1
profbuxton
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TL;DR Summary
Do all EM waves exhibit interference patterns as per the slit experiment with photons?
Not a physicist. Background is in electronics over many years. Have recently been "binge" watching youtube lectures on the "dreaded" QUANTUM MECHANICS by various people(Susskind, Feynman et al) and trying to comprehend the whole thing.
While I can generally follow the lectures I must admit the symbology and the maths is a bit(greatly, actually) over my head.
My question is as follows: Since it seems that photons of light seem to act as particles at some stage but also exhibit wave charactheristics and they are part of a spectrum of the electromagnetic waves covering low(relatively) frequencies to the high end of the spectrum (x-rays and gamma rays) should not ALL of this spectrum exhibit similar behaviour. For instance, radio waves should be able to be shown to behave as particles and also waves(as per the slit experiment.
This would also apply to the high frequency end( microwaves, x-rays and gamma ray)surely.
I can only imagine that no-one has demonstrated this due to the difficulty of building test equipment suitable for the task.
I assume one would need to make special slits and detectors for the experiment which may be beyond current efforts. I am not aware of any experiments done with any frequencies other than in the visible light part of the spectrum to show the same effect(particle or wave interference) for EM fields other than light.
I guess the question is: Would ALL EM frequencies in the spectrum show particle behaviour or only a special part of the EM spectrum? What
about the magnetic wave associated with electric fields.
Thanks for your interest. I will keep watching the lectures and try to get my thoughts around this difficult(to me) subject.
 
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  • #2
EM radiation is all the same stuff, basically. The energy of a photon of any frequency f of EM is E=hf . h is Planck's constant.
h
= 6.62607015×10−34 J⋅Hz−1 which is a very small quantity. The individual photon energy for visible light is millions of times higher than for microwaves. The energy of a single photon of visible light is small but can be detected fairly easily. It is enough to make Photo-electric cells work and provide PV energy for homes and TV cameras.
You can also detect individual photons of IR too but beyond this, you have the problem that the energy due to the temperature of the detector can affect the Signal to Noise ratio so that the individual photons have less energy than the electrons in the detector. So you cannot easily distinguish between them. There is no fundamental lower frequency limit but this link (just read the title!) shows just how difficult they are to detect.
 
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  • #3
EM Waves of all frequencies exhibit particle and wave behavior. But the particle behavior is more easily detectable for high frequencies, while the wave behavior is more easily detectable for low frequencies.
 
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  • #4
Thanks,sophiecentaur, for your reply. So my "deduction" was almost correct, in that it all revolves around wavelength and the difficulty of detection apparatus. The one issue I did not allow for was the energy factor. Maybe at some time technology will allow us to do this experiment for more EM frequencies,maybe.
If I may be allowed to ask another question re photons,
I understand that a photon will "energize" an electron that it "strikes"(or matches with somehow) and this electron gains energy to move to a higher energy state. Given that we have determined that an atom is mostly "empty" has a photon ever been observed to "strike" a nucleus or is that not "allowed" due to the "positive" charge around the nucleus even though a photon has no charge(as I understand it). Thanks.
 
  • #5
Gamma photons have high enough energy to affect atomic nuclei.
Lower frequency photons (eg RF) will not just just interact with individual electrons. Whole molecules are affected and also the currents in wires etc..
 
  • #7
profbuxton said:
Summary:: Do all EM waves exhibit interference patterns as per the slit experiment with photons?

I am not aware of any experiments done with any frequencies other than in the visible light part of the spectrum to show the same effect(particle or wave interference) for EM fields other than light.
Phased array antennas used the interference from many sources (and therefore receivers) in a more or less flat 2D geometry to steer the beam by controlling the relative phase. These are typically GHz items and replace mechanically steered dishes.
Astronomers regularly use aperture synthesis techniques to do radio astronomy on much longer wavelengths.
Its all the physics of interference.
 
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  • #8
hutchphd said:
Phased array antennas used the interference from many sources (and therefore receivers) in a more or less flat 2D geometry to steer the beam by controlling the relative phase.
. . . or any multi element array that has directivity.
hutchphd said:
Its all the physics of interference.
absolutely.

And, of course, any antenna that's large, compared with the wavelength will have a pattern due to diffraction.
 
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FAQ: Question re photons/EM waves and the double slit experiment

What is the double slit experiment?

The double slit experiment is a classic experiment in physics that demonstrates the wave-particle duality of light. It involves shining a beam of light through two parallel slits and observing the resulting interference pattern on a screen. This experiment has been used to study the properties of photons and electromagnetic waves.

What is the significance of the double slit experiment?

The double slit experiment is significant because it challenges our understanding of the nature of light. It shows that light can behave as both a wave and a particle, depending on how it is observed. This experiment has also been used to support the theory of quantum mechanics and has led to further discoveries in the field of physics.

How does the double slit experiment relate to photons and electromagnetic waves?

The double slit experiment is used to study the properties of photons and electromagnetic waves. By observing the interference pattern created by the light passing through the slits, scientists can determine the wavelength and frequency of the light, as well as its particle-like behavior. This experiment has provided valuable insights into the nature of light and its behavior.

Can the double slit experiment be replicated with other particles?

Yes, the double slit experiment has been replicated with other particles such as electrons, neutrons, and even large molecules. The results of these experiments have been consistent with the behavior of light, further supporting the wave-particle duality of matter.

What are the practical applications of the double slit experiment?

The double slit experiment has practical applications in fields such as optics, quantum mechanics, and information technology. It has also been used in the development of technologies such as electron microscopy and diffraction gratings. Additionally, the principles learned from this experiment have led to advancements in fields such as quantum computing and cryptography.

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