Tagged Questions
5
votes
1answer
67 views
Photons: Collection of Wave Packets that produce a plane wave
Is it possible mathematically for photons, which behave as individual Gaussian wave packets, to combine in such a way that the approximate result is a plane wave at one particular frequency (i.e., the ...
5
votes
2answers
188 views
Why is the photon emitted in the same direction as incoming radiation in Laser?
When an atom “lases” it always gives up its energy in the same direction and phase as the incoming light. Why does this happen? How can this be explained?
How does the photon generated because of ...
30
votes
5answers
4k views
Why doesn't light kill me?
I was attending my philosophy class and in the middle of student presentations, I found myself mentally wondering off and thinking about light. After a few minutes of trying to piece together how the ...
0
votes
0answers
21 views
Does quantum mechanics depend solely on electromagnetic waves? [duplicate]
I am beginning to learn quantum mechanics. Since determining the position of an object involves probing by electromagnetic waves and since i have read a simple derivation of Heisenberg's uncertainty ...
1
vote
1answer
83 views
How can we detect X-rays?
I know that X-rays can be detected by various ways, like ionizing of air particles.
Is there a way to detect X-rays,which are photons, by detecting ? Can something absorb the energy of the X-rays and ...
2
votes
1answer
68 views
Is the de Broglie wavelength of a photon equal to the EM wavelength of the radiation?
Is the de Broglie (matter) wavelength $\lambda=\frac{h}{p}$ of a photon equal to the electromagnetic wavelength of the radiation?
I guess yes, but how come that photons have both a matter wave and an ...
2
votes
1answer
80 views
Difference between electromagnetic radiation (EMR) and Electromagnetic Field?
I'm a freshly graduated electrical engineer. One course that I really struggled with was Field Theory, because it was a lovely assortment of vector calculus and things that were explained to me well ...
2
votes
1answer
99 views
Where is the amplitude of electromagnetic waves in the equation of energy of e/m waves? [duplicate]
Does the amplitude of the photon oscillations always stay constant and if it is not - what are the physical differences between the photon with higher amplitude in comparison to the one with the less ...
4
votes
2answers
195 views
How photons represent colors that you see?
Right now, my understanding is that, a mixture of photons of many different frequencies is perceived as white by your eye. While no photons at all, is perceived as black. And photons with the blue ...
1
vote
2answers
111 views
Do photons actually generate a slight kinetic force?
My question is even though photons have no (rest) mass, do they emit a external force due to EM radiation causing electrons to be excited and jump to higher energy shells which electrons have mass ...
5
votes
2answers
206 views
If photons move linearly, what's actually stopping them from passing through a microwave oven mesh?
So, my understanding is that the wavelength of a photon is the distance traveled in the time it takes it's magnetic field to oscillate. And it's inversely proportional to it's energy and it's ...
1
vote
2answers
238 views
What is light, and how can it travel in a vacuum forever in all directions at once without a medium?
I know there are many questions that are similar (maybe identical?). I am not a physicist nor a student - I am just interested in physics and have been watching many physics channels on youtube ...
1
vote
1answer
144 views
How photons move along with EM wave?
So the wave moves like. a wave, it moves up and down, up and down. But how do photons move? Do they follow the same path or do they just go straight forward without oscillating?
14
votes
3answers
844 views
Amplitude of an electromagnetic wave containing a single photon
Given a light pulse in vacuum containing a single photon with an energy $E=h\nu$, what is the peak value of the electric / magnetic field?
0
votes
0answers
52 views
Electromagnetic charge [duplicate]
Possible Duplicate:
If electromagnetic field give charge to particles, does photon carry charge?
Is it possible to charge photons
I was wondering if light when it's in wave form (seeing ...
6
votes
5answers
814 views
Why is Light invisible?
Why can't we see light? The thing which makes everything visible is itself invisible. Why is it so?
6
votes
1answer
235 views
Why is there a photon every millimeter on earth coming from a star millions of light years away?
I've been having this confusing thought for so long now it would be amazing if someone could answer me.
Imagine this asterisk * . As you see, from the center point, lines go outwards, just like a ...
0
votes
1answer
154 views
The electron jumps and lets loose photons
Where is the source of the photon.
If the photon propagates from within the electrons transit does this point to some sort of field?
Does the energy come from a boundary being broken in laymens ...
1
vote
2answers
158 views
PV cell for invisible spectrum only
Is it possible to make a photovoltaic cell that would only absorb the invisible part of the electromagnetic spectrum, while letting visible light pass through or bounce off its surface?
I guess that ...
1
vote
2answers
292 views
Frequency and wavelength of photons
I try to better understand how electromagnetic radiation works. So I have some questions.
If an antenna emits at 100MHz (the charges on the antenna oscillate at 100MHz) what frequency will have the ...
1
vote
2answers
647 views
Producing photons with same frequency, different amplitude wave
I don't understand how two photons of the same frequency can have different amplitudes, neither how to produce them.
I know that classically the square of the amplitude is proportional to the energy, ...
3
votes
2answers
326 views
Is the electron wave function defined during photon emission
I have heard the term quantum leap to describe the (instantaneous?) transition from a higher energy orbital to a lower energy orbital. Yet, I understand that this transition time has now been ...
4
votes
2answers
222 views
What frequency photons are involved in mediating physical force?
If the force felt when pushing an object is mediated by the electromagnetic interaction and hence photons, what is their frequency?
4
votes
1answer
1k views
Why are lasers inefficient?
Why are lasers inefficient? Is it because of the heat lost during lasing? Why couldn't there be thermocouples or turbines in parts of the cooling circuits to extract something out of that heat?
3
votes
1answer
235 views
Is there a limit to the visual information a photon can carry?
As photons bounce around and finally find their way into our eyes, are they continually relinquishing the information of the previous thing they "bounced off of"? Is this the reason why we receive a ...
3
votes
3answers
132 views
Distant bodies emitting photons
This comes from a discussion forum, where a friend of mine asked the following:
We can see objects in space billion of light years away, right? I started wondering about that.
If you take 2 ...
3
votes
1answer
745 views
Light waves and Schrödinger probability waves
Ok, bearing in mind that I only have a brief understanding of quantum mechanics (no formal education, only from reading about concepts in books), so I could be way off here, I have a question ...
-5
votes
3answers
298 views
Could a bubble of photons make a spaceship massless?
I'm not sure how theoretically possible this is but my question is...
If we could somehow make a perfect bubble of photons (a massless bubble) and put a spaceship inside it, could it therefore ...
2
votes
3answers
690 views
Reconciling refraction with particle theory and wave theory
I have searched the web for good answers to why refraction occurs when light moves from one medium to another with different density. I have limited background in physics and want to know if there is ...
4
votes
4answers
1k views
Do mirrors increase the amount of light in a room?
So if you have a light bulb in a room, and you had a tool to measure the amount of light that's in the room, then let's assume the amount of light only caused by the bulb is "1"
If you place a mirror ...
6
votes
3answers
2k views
Properties of the photon: Electric and Magnetic field components
Consider an electromagnetic wave of frequency $\nu$ interacting with a stationary charge placed at point $x$. My question concerns the consistency of two equally valid quantum-mechanical descriptions ...
25
votes
9answers
14k views
If photons have no mass, how can they have momentum?
As an explanation of why a large gravitational field (such as a black hole) can bend light, I have heard that light has momentum. This is given as a solution to the problem of only massive objects ...
