Wave interference and energy conservation

In summary, when two light waves with the same frequency and intensity meet, their crest and trough cancel each other out, resulting in no light. However, this is not the case in particle physics. In the collision of an electron and a positron, both particles have positive energy and when they meet, they annialate each other, releasing energy in the form of two photons. The only instance where no energy is released is with virtual particles, which appear and disappear without consuming or releasing any energy.
  • #1
Bill Minerick
8
0
If the crest of one light wave meets the trough of another light wave of the same frequency and intensity they supposedly cancel each other resulting in no light (e.g., the dark areas that result on the screen when both slits are open on a dual slit experiment). In particle physics, why then does the collision of an electron and a positron result in the release of a photon vs. just no energy at all?
 
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  • #2
When light interferes ,the energy does not just disappear. You will get spots where there is destructive interference, and spots with constructive interference; the energy is isolated into the bright bands. As for the collision of an electron and a positron, both have positive energy (ie it takes energy to make them, me*c^2 for both), and so when they meet, they annialate each other releasing energy in the form of two photons (for momentum conservation).
The closest you can get to the release of no energy is with virtual particles; they spring into existence and then annialate each other, consuming or releasing no energy in the process.
 
  • #3


I can explain that the phenomenon of wave interference and energy conservation is a complex and fundamental concept in physics. In the example mentioned, when the crest of one light wave meets the trough of another light wave, they do not completely cancel each other out. Instead, they interfere with each other, resulting in a decrease in the intensity of the light. This is because light is a form of electromagnetic radiation that exhibits wave-like properties, and when two waves meet, they can either reinforce or cancel each other out depending on the phase of the waves.

In the case of a dual slit experiment, the dark areas on the screen are a result of destructive interference, where the waves cancel each other out and result in no light. However, this does not mean that no energy is present in those areas. The energy of the light waves is still present, but it is distributed differently due to the interference.

In particle physics, the collision of an electron and a positron does not result in the release of a photon because of wave interference, but rather because of the conversion of mass into energy. According to Einstein's famous equation, E=mc², energy and mass are equivalent and can be converted into each other. When an electron and a positron collide, they annihilate each other, converting their mass into energy in the form of a photon. This process follows the principle of energy conservation, where the total energy before and after the collision remains the same.

In summary, the concept of wave interference and energy conservation applies to both light waves and particles in different ways. In the case of light waves, interference can result in a decrease in intensity, while in particle collisions, energy is conserved through the conversion of mass into energy. It is essential to understand the underlying principles and mechanisms behind these phenomena to gain a deeper understanding of the behavior of energy in the universe.
 

1. What is wave interference?

Wave interference refers to the phenomenon of two or more waves overlapping and interacting with each other. This can result in constructive interference, where the waves combine to create a larger amplitude, or destructive interference, where the waves cancel each other out.

2. How does wave interference occur?

Wave interference occurs when two or more waves meet at the same point in space and time. The waves will interact with each other, either adding together or subtracting from each other, depending on their amplitudes and phases.

3. What is energy conservation in relation to wave interference?

Energy conservation in wave interference refers to the fact that the total energy of the waves before and after interference remains constant. This means that the energy of the waves is redistributed during interference, but is not created or destroyed.

4. How does wave interference affect the amplitude of a wave?

Wave interference can either increase or decrease the amplitude of a wave, depending on whether it is constructive or destructive. Constructive interference occurs when waves with similar amplitudes and phases overlap, resulting in a larger amplitude. Destructive interference occurs when waves with opposite phases overlap, resulting in a smaller or zero amplitude.

5. Can wave interference occur in different types of waves?

Yes, wave interference can occur in all types of waves, including electromagnetic waves, sound waves, and water waves. However, the specific effects of interference may vary depending on the properties of the waves, such as wavelength and frequency.

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