Would light speed be faster with no virtual particles

AI Thread Summary
Light travels slower in mediums like water compared to a vacuum, but the presence of virtual particles does not impede its speed in a vacuum. Virtual particles are considered non-physical and do not affect the movement of real particles, despite their interactions in quantum electrodynamics (QED). The discussion touches on concepts like Hawking radiation, suggesting that the behavior of particles near black holes does not necessarily require the existence of virtual particles. Some participants argue that virtual particles are essential for understanding phenomena like Lamb's shift, while others maintain they do not influence light speed. Overall, the connection between light and virtual particles remains a complex topic in quantum physics.
Meatbot
Messages
146
Reaction score
1
Light travels slower in mediums like water than it does in the vacuum. Would it be even faster in the vacuum if the vacuum were "true" and there were no virtual particles popping into existence? Shouldn't light be slowed by them?
 
Science news on Phys.org
Would there be light, as we know it, without the virtual particles?
 
Light travels slower in mediums like water than it does in the vacuum.

Nope. Virtual particles are *virtual* and therefore not physical and therefore not an impediment to anything moving in our universe.

- Bryan
 
kanzure said:
Nope. Virtual particles are *virtual* and therefore not physical and therefore not an impediment to anything moving in our universe.

- Bryan

The *virtual* particles interact with *real* particles, and so it seems they are as physical as real particles. Refer Lamb's shift, one of the first phenomenon of this kind to be understood.

My initial post was to point out to the OP that photons, as we know them, and virtual particles are intimately connected by QED. (I made no comment about the speed of photons, which was the OP's query.)
 
Shooting star said:
My initial post was to point out to the OP that photons, as we know them, and virtual particles are intimately connected by QED. (I made no comment about the speed of photons, which was the OP's query.)

Can you explain or point me somewhere to read up on it? Thanks.
 
I'll just give you two links chosen at random almost, with very little material in them actually. After that, you can simply search for "virtual particles" and there are numerous sites.

http://www.sciam.com/physics/article/id/are-virtual-particles-rea
http://cr4.globalspec.com/blogentry/2784/Real-and-Virtual-Particles-Part-II
 
kanzure said:
Nope. Virtual particles are *virtual* and therefore not physical and therefore not an impediment to anything moving in our universe.

How is Hawking radiation explained if they are not physical, or do they only become physical when one is captured? Even if the original pair aren't physical, the particle that is not caught by the hole should interfere and light should be slowed by those. Should we see light moving slower near black holes from the buildup of the orphan particles? A black hole with no matter originally in orbit should eventually accumulate orbiting orphaned virtual aprticles, should it not?
 
Last edited:
Meatbot said:
How is Hawking radiation explained if they are not physical, or do they only become physical when one is captured?

Well, you could interpret Hawking radiation as being due to particles tunneling through the potential barrier to escape. That doesn't need to invoke virtual particles.
 
Back
Top