Clarification virtual photons, real photons

In summary: However, virtual particles (photons or gravitons) can be exchanged between masses or charges and contribute to their interaction. These virtual particles do not have the same properties as real particles and cannot be detected or measured in the same way. Therefore, they cannot be counted or observed. In summary, virtual photons and radiated photons are different in that virtual photons are not observable, while radiated photons can be detected with a camera sensor. Virtual photons are also not said to propagate between two points, unlike real photons. Similarly, gravitational waves are not the source of attraction between two masses, but rather the curvature of spacetime. They are similar to EM waves in that they are the result of accelerated charges and travel at the speed of light, but
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Albertgauss
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I need clarification on the difference between a virtual photon of a transmitted force and “radiated photons” of accelerated charges.

Imagine two electric charges separated by a distance “d” but not moving. They exchange virtual photons which tell the electric charges to attract/repel. How are these virtual photons the same/different to the real photons emitted from accelerated charge like in an antenna?

Why can’t virtual photons be detected from non-accelerating electric charges? If they are truly present, and cause the real observable attraction and repulsion of electric charges, shouldn’t they be able to be detected going back and forth between the electric charges? It seems that photons are photons.

This now applies to gravity waves. Similarly, I know that masses exchange gravity waves from which they know to attract. If such gravity waves really are present between the masses, shouldn’t I be able to detect them? Yet I know that accelerated masses are required for the detection of gravity waves also (LIGO). This seems like a contradiction. Aren’t the gravity waves always there, always moving between the masses, whether the masses accelerate or not? Or like, with electromagnetism, is there some fundamental difference I am missing between the virtual photons? of gravity and the gravitational radiation we observe from binary black holes?

Is the graviton the "virtual photon" responsible for the attraction of masses in gravrity?
 
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Albertgauss said:
Imagine two electric charges separated by a distance “d” but not moving. They exchange virtual photons which tell the electric charges to attract/repel. How are these virtual photons the same/different to the real photons emitted from accelerated charge like in an antenna?

You can't observe them. Ever.

Real photons can be counted with a detector (like a camera sensor) and propagate at the speed of light. Virtual photons cannot be counted. A camera sensor will not detect them. They cannot even be said to propagate between two points.

Albertgauss said:
This now applies to gravity waves. Similarly, I know that masses exchange gravity waves from which they know to attract.

This is incorrect. Gravitational waves are not the source of the attraction between two masses. That belongs to the curvature of spacetime, not to the waves within it.

Albertgauss said:
Aren’t the gravity waves always there, always moving between the masses, whether the masses accelerate or not? Or like, with electromagnetism, is there some fundamental difference I am missing between the virtual photons? of gravity and the gravitational radiation we observe from binary black holes?

Gravitational waves are similar to EM waves in that they are the result of accelerated charges (positive and negative charges in EM, acceleration of masses in gravity). They both travel at the speed of light and carry energy away from their source. Neither the photons composing the EM waves nor the gravitons composing the gravitational waves (if they exist) are virtual. They are real.
 
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FAQ: Clarification virtual photons, real photons

1. What is the difference between virtual photons and real photons?

Virtual photons are particles that exist only temporarily as a result of quantum fluctuations, while real photons are particles that exist as a constant and measurable entity. Virtual photons are responsible for mediating the electromagnetic force between charged particles, while real photons are the fundamental particles of light.

2. How are virtual photons created?

Virtual photons are created when a charged particle emits or absorbs energy. This process can occur spontaneously due to quantum fluctuations, or it can be induced by the presence of another charged particle.

3. Can virtual photons be detected?

No, virtual photons cannot be directly detected because they exist only for a brief moment and do not have enough energy to be measured. However, their effects can be observed through the interactions between charged particles.

4. What is the role of virtual photons in the quantum vacuum?

Virtual photons play a crucial role in the quantum vacuum as they constantly pop in and out of existence, mediating the interactions between particles and giving the vacuum its energy and structure.

5. Are virtual photons important in everyday life?

While virtual photons are not directly observable in our daily lives, they play a crucial role in the behavior of matter and energy at the subatomic level. Without virtual photons, many fundamental forces and interactions in the universe would not exist.

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