# The Naked Scientists Forum

### Author Topic: Does light have mass?  (Read 76472 times)

• Neilep Level Member
• Posts: 1451
##### Does light have mass?
« Reply #150 on: 01/11/2009 20:12:27 »
You know, instead of posting several times in the space of 5 minutes, it is possible to edit your post and add to it.

#### ezgoinguy1964

• First timers
• Posts: 1
##### Does light have mass?
« Reply #151 on: 07/11/2009 05:21:26 »
The way I understand it, GRAVITY is defined as an effect between two bodies that have mass.  Therefore as light is affected by massive objects it too must have mass.  This seems to contain a paradox of sorts as according to Einstien's theory of relativity nothing with mass can ever travel at the speed of light.  If this is true then even light shouldn't be able to travel at the speed of light.  Can someone explain this to me?  I know there must be a simple answer, or maybe its a dumb question, but its been perplexing me lately.

#### Vern

• Neilep Level Member
• Posts: 2072
##### Does light have mass?
« Reply #152 on: 07/11/2009 07:10:07 »
This problem comes up because we have not yet admitted that we know just exactly what is mass. We have it well established in our equations and we can use the equations to solve problems every day. But for some reason we just don't admit that we know exactly what mass is. Well, we do know. Mass is electromagnetic change. M = hv / c2.

It is the rate of change of electromagnetic fields in a local area that give us the measure of the amount of mass in that local area. When the amount is enough to give us atoms and molecules we need to use a different magnitude of measure but we know at the most elemental level it is still the change that produces the effect.

So, when we admit that we know that mass is electromagnetic change we see that light does not have mass. Light is mass. And not only is light mass, but light is the only kind of mass that there is.

These are my speculations; don't take these to class. Just use this notion in your quest to understand how nature works.

« Last Edit: 07/11/2009 07:26:00 by Vern »

#### Mr. Data

• Sr. Member
• Posts: 275
##### Does light have mass?
« Reply #153 on: 29/06/2011 12:32:22 »
If you want, I can show you all why light does not have a mass... in fact... I could explain symmetry breaking for you all. Takes a bit of time using this system since it does not use latex for mathematics, so before I make any statements, I would like to know if people want to learn first.

#### The Naked Scientists Forum

##### Does light have mass?
« Reply #153 on: 29/06/2011 12:32:22 »