Understanding Photon Emission: Random Time Delay and Duration Explained

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Photon emission occurs in discrete bursts, known as wave packets, rather than continuously. Each photon is emitted individually with a random time delay, and while the duration of a photon from white light is approximately 10^-9 seconds, this does not imply that photons cease to exist after this time; they persist until absorbed. The discussion clarifies that photons do not "die out" but continue traveling until they interact with matter. The concept of emission timing suggests that after the first photon is emitted, subsequent photons may follow at unpredictable intervals. Understanding these principles is crucial for grasping the nature of light and photon behavior.
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hi, as we know, lamp emits light not continuously but in 'burst', which we may call wave packet or photon. my question is,
1. Is it emitted one photon by one photon with random time delay ?
2. it is said that the duration time of the photon from white light is about 10^-9 sec(nanosecond), does it mean that each photon lasts for 10^-9 sec ?
3. if the above two questions are both correct, then does it mean that 10^-9 sec late after the emission of the first photon, wait an unpredictable time later, another photon emitted ? then how about the first one ? where does it go ? die out ?

can anyone help ? thank you so much !
 
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Photons don't 'die out'. They continue until they are absorbed, at which time they no longer exist as photons.

Surely you can see this must be so ? If each photon lasted only for a short time, we would be in a dark universe. When you look at starlight, some of it could have been traveling for hundreds of millions of years to get to your eye and be absorbed.
 
coke said:
2. it is said that the duration time of the photon from white light is about 10^-9 sec(nanosecond),

Where does it say that?
 
coke said:
hi, as we know, lamp emits light not continuously but in 'burst', which we may call wave packet or photon. my question is,

I don't get this. Care to elaborate, please ? What's this "burst" you are talking about ?

marlon
 
Time reversal invariant Hamiltonians must satisfy ##[H,\Theta]=0## where ##\Theta## is time reversal operator. However, in some texts (for example see Many-body Quantum Theory in Condensed Matter Physics an introduction, HENRIK BRUUS and KARSTEN FLENSBERG, Corrected version: 14 January 2016, section 7.1.4) the time reversal invariant condition is introduced as ##H=H^*##. How these two conditions are identical?

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