Would light speed be faster with no virtual particles

[Meatbot]

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?

[Shooting Star]

Would there be light, as we know it, without the virtual particles?

[kanzure]

Light travels slower in mediums like water than it does in the vacuum.

Nope (http://www.physicsforums.com/showpost.php?p=1558381&postcount=2). Virtual particles are *virtual* and therefore not physical and therefore not an impediment to anything moving in our universe.

- Bryan

[Shooting Star]

Nope (http://www.physicsforums.com/showpost.php?p=1558381&postcount=2). 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.)

[Meatbot]

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.

[Shooting Star]

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

[Meatbot]

Nope (http://www.physicsforums.com/showpost.php?p=1558381&postcount=2). 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?

[Mute]

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.