Clarification virtual photons, real photons

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SUMMARY

The discussion clarifies the distinction between virtual photons and real photons, emphasizing that virtual photons facilitate force interactions between static electric charges but cannot be detected. Real photons, emitted by accelerated charges, can be observed and propagate at the speed of light. The conversation also addresses gravitational waves, asserting that they are not the source of gravitational attraction; rather, this attraction arises from the curvature of spacetime. The concept of gravitons as potential carriers of gravitational force is explored, concluding that both gravitational and electromagnetic waves are real phenomena resulting from acceleration.

PREREQUISITES
  • Understanding of quantum field theory and the role of virtual particles
  • Knowledge of electromagnetic radiation and photon behavior
  • Familiarity with general relativity and the concept of spacetime curvature
  • Basic principles of gravitational waves and their detection methods
NEXT STEPS
  • Study quantum electrodynamics to understand virtual photons in depth
  • Explore the principles of general relativity and spacetime curvature
  • Research gravitational wave detection techniques, particularly LIGO
  • Investigate the theoretical framework surrounding gravitons and their implications
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Physicists, students of theoretical physics, and anyone interested in the fundamental interactions of forces and the nature of light and gravity.

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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