Philosophy Forums
Forums Links Articles Gallery Chat
Style:



Register | Forgot Password

What is light?

printPrint


Page: 1 2 3 4

What is light?
ronjanec
Graduate

Usergroup: Members
Joined: Sep 04, 2008
Total Topics: 6
Total Posts: 139
Posted 09/09/08 - 07:14 AM:
Subject: What is light?
quote post
#1
Light is a particle? Light is a wave? Can light be both things or wave/particle? Some experiments appear to prove that light is a particle and others appear to prove that light is a wave?
Death Monkey
Tenured Poster
Avatar

Usergroup: Members
Joined: Sep 18, 2003
Location: Eindhoven, The Netherlands
Total Topics: 7
Total Posts: 2430
Posted 09/09/08 - 08:08 AM:
quote post
#2
Light is the propogation of fluctuations of the electromagnetic field. This field is quantized. The quanta of the field are called photons. Under some conditions photons behave similarly (but not identically) to classical particles. Under other conditions light behaves similarly (but not identically) to classical waves.


DM

Pseudoscience makes Baby Jesus cry.
ronjanec
Graduate

Usergroup: Members
Joined: Sep 04, 2008
Total Topics: 6
Total Posts: 139
Posted 09/09/08 - 08:25 AM:
quote post
#3
DM would you say the light in the room that I am writing this is particles or waves?
ronjanec
Graduate

Usergroup: Members
Joined: Sep 04, 2008
Total Topics: 6
Total Posts: 139
0 of 1 people found this post helpful
Posted 09/09/08 - 11:30 AM:

quote post
#4
I personally believe that light is a stream of particles traveling in a wavelike pattern. The particles are moving so fast that they appear to man as a wave. (The experiments man conducts actually destroy the wave and only show the particle nature) Everyone please feel free to criticize this post and try to pick it apart in every way you possibly can. I guess philosophy is only for people who agree with the conventional wisdom and cynics need not apply.
Death Monkey
Tenured Poster
Avatar

Usergroup: Members
Joined: Sep 18, 2003
Location: Eindhoven, The Netherlands
Total Topics: 7
Total Posts: 2430
Posted 09/09/08 - 01:28 PM:
quote post
#5
ronjanec,

DM would you say the light in the room that I am writing this is particles or waves?

No, I would not.

As I said in my previous post, particles and waves are classical descriptions. Neither of these descriptions is completely accurate.

I personally believe that light is a stream of particles traveling in a wavelike pattern. The particles are moving so fast that they appear to man as a wave. (The experiments man conducts actually destroy the wave and only show the particle nature) Everyone please feel free to criticize this post and try to pick it apart in every way you possibly can.

What you believe is not consistent with the scientific evidence.

I guess philosophy is only for people who agree with the conventional wisdom and cynics need not apply.

This isn't philosophy. It is physics. And physics, like philosophy, is for anybody willing to make the effort to understand what he is discussing. Conventional wisdom is not the issue here. Empirical evidence is.


DM

Pseudoscience makes Baby Jesus cry.
swstephe
Tenured Poster
Avatar

Usergroup: Moderators
Joined: Apr 20, 2006
Location: borneo island
Total Topics: 22
Total Posts: 2124
Posted 09/09/08 - 10:10 PM:
quote post
#6
It would be more correct to say: sometimes light behaves in a way that is similar to the way we would expect a stream of particles to behave, but there are times when light behaves in a way similar to what is observed in waves traveling through a medium, (like water or air). There are properties which would indicate that it isn't either, if treated like a particle, it has no mass and travels at the speed of light. As a wave, it doesn't seem to depend on any fixed media -- about 100 years ago, some people thought there was an invisible "ether" which is what was vibrating to these waves. Quantum mechanics tries to unify these models. String theory tries some multi-dimensional approaches.

The philosophical problem is that there are these things which are neither truly particles, (matter), nor truly waves, (energy), which doesn't behave like anything else we can easily perceive or describe and what does this do to our understanding of reality ... if that makes a difference.

"There are only two industries that refer to their customers as 'users'." -- Edward Tufte
Kwalish Kid
Tenured Poster
Avatar

Usergroup: Members
Joined: Sep 26, 2004
Total Topics: 22
Total Posts: 2973
Posted 09/10/08 - 03:50 AM:
quote post
#7
ronjanec wrote:
I guess philosophy is only for people who agree with the conventional wisdom and cynics need not apply.

Again you bring the wisdom of the crackpot. Philosophy is not the practise of spouting out grand claims to make yourself feel better. Your actions are insulting to people who actually take the time to do scientific research.

"Scientific truth is always paradox, if judged by everyday experience, which catches only the delusive nature of things." - KM, V, P and P

"A fishnet is made up of a lot more holes than strings, but you can't therefore argue that the net doesn't exist. Just ask the fish." - Jeffrey Kluger

"…Love of God and compassion and empathy leads you to a very glorious place, and science leads you to killing people." -Ben Stein [This is included for the irony.]
ragus
Tenured Poster
Avatar

Usergroup: Members
Joined: Apr 23, 2006
Total Topics: 16
Total Posts: 1513
Posted 09/10/08 - 11:03 AM:
quote post
#8
What sort of person would be insulted by a crackpot?

feeling cheerful
ragus
Tenured Poster
Avatar

Usergroup: Members
Joined: Apr 23, 2006
Total Topics: 16
Total Posts: 1513
Posted 09/10/08 - 11:09 AM:
quote post
#9
Death Monkey wrote

Light is the propogation of fluctuations of the electromagnetic field.


Does the electromagnetic field fill space and the fluctuations move through this?

feeling cheerful
Death Monkey
Tenured Poster
Avatar

Usergroup: Members
Joined: Sep 18, 2003
Location: Eindhoven, The Netherlands
Total Topics: 7
Total Posts: 2430
Posted 09/11/08 - 12:43 PM:
quote post
#10
ragus,

Does the electromagnetic field fill space and the fluctuations move through this?

It is a function of position that takes on values at all positions, so in that sense you could say that it "fills space".

I am not sure what the "this" you are referring to is when you say "move through this". When the field changes at some position, for example due to an accellerating electric charge, the change propagates through space at the speed of light.


DM

Pseudoscience makes Baby Jesus cry.
Download thread as

Page: 1 2 3 4



You don't have permission to post.

Please login or register.

4 total queries
This page was created in 1.28 seconds
Memory used: 3056536 bytes
Server Status: time since last reboot is 246 days, 21:34, load average: 2.38, 3.48, 3.54