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Dave Tweed
Dave Tweed
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No, the system cannot distinguish individual photons.

A single photon at, say, 10 GHz has an energy of about 6.62607015×10−24 J. A barely-detectable radio signal has a power of about 1 femtowatt, or 10-15 J/sec, which represents (10-15 J/sec)/(6.62607015×10−24 J/photon) = about 1.8×1018 photons/sec.

While the antenna can be thought of as interacting with individual photons, there's simply no way that you can detect the effects of a single photon buried in the midst of all the other photons.

Your instructor is not doing you any favors by describing the process in this way. The electrical signal you get from an antenna arises from the statistical properties of vast numbers of photons, only some of which represent the desired signal. It is far more useful to think of it in terms of relative field strengths in fields and voltage/current levels in wires. The purpose of the antenna is to convert from one to the other.

No, the system cannot distinguish individual photons.

A single photon at, say, 10 GHz has an energy of about 6.62607015×10−24 J. A barely-detectable radio signal has a power of about 1 femtowatt, or 10-15 J/sec, which represents (10-15 J/sec)/(6.62607015×10−24 J) = about 1.8×1018 photons/sec.

While the antenna can be thought of as interacting with individual photons, there's simply no way that you can detect the effects of a single photon buried in the midst of all the other photons.

Your instructor is not doing you any favors by describing the process in this way. The electrical signal you get from an antenna arises from the statistical properties of vast numbers of photons, only some of which represent the desired signal. It is far more useful to think of it in terms of relative field strengths in fields and voltage/current levels in wires. The purpose of the antenna is to convert from one to the other.

No, the system cannot distinguish individual photons.

A single photon at, say, 10 GHz has an energy of about 6.62607015×10−24 J. A barely-detectable radio signal has a power of about 1 femtowatt, or 10-15 J/sec, which represents (10-15 J/sec)/(6.62607015×10−24 J/photon) = about 1.8×1018 photons/sec.

While the antenna can be thought of as interacting with individual photons, there's simply no way that you can detect the effects of a single photon buried in the midst of all the other photons.

Your instructor is not doing you any favors by describing the process in this way. The electrical signal you get from an antenna arises from the statistical properties of vast numbers of photons, only some of which represent the desired signal. It is far more useful to think of it in terms of relative field strengths in fields and voltage/current levels in wires. The purpose of the antenna is to convert from one to the other.

Source Link
Dave Tweed
Dave Tweed
  • 178.3k
  • 17
  • 242
  • 418

No, the system cannot distinguish individual photons.

A single photon at, say, 10 GHz has an energy of about 6.62607015×10−24 J. A barely-detectable radio signal has a power of about 1 femtowatt, or 10-15 J/sec, which represents (10-15 J/sec)/(6.62607015×10−24 J) = about 1.8×1018 photons/sec.

While the antenna can be thought of as interacting with individual photons, there's simply no way that you can detect the effects of a single photon buried in the midst of all the other photons.

Your instructor is not doing you any favors by describing the process in this way. The electrical signal you get from an antenna arises from the statistical properties of vast numbers of photons, only some of which represent the desired signal. It is far more useful to think of it in terms of relative field strengths in fields and voltage/current levels in wires. The purpose of the antenna is to convert from one to the other.