"Ed Lake" wrote in message
news:c1f0b118-1bb2-41fe-9776-891f1fbd6fbdn@googlegroups.com...

>We also know that a photon has no mass.

This is a misnomer.

Light has

mass = E/c^2

E=hf.

p=h/lamda

"no mass" essentially means "if a photon were to travel at zero velocity it
would have no mass"

A photon always at c thus the pop media description "massless" is
misleading.

Mass is any object that has inertia and gravitates. Light does both, thus
must have mass

Many are confused on energy.

All energy is mass in motion. Energy is a real physical object, it is not
ectoplasm, its mass. All physical real objects must have mass.

The motion of mass can be rearranged to appear as a physical material
particle or a physical non material particle.

Unfortunately, many have the nonsensical view that one can convert one
substance into another. One can make many things with Lego, but they are all
plastic.

Kevin Aylward

https://www.kevinaylward.co.uk/gr/index.html
http://www.anasoft.co.uk/ SuperSpice
http://www.kevinaylward.co.uk/ee/index.html

On 7/13/22 10:57 AM, Kevin Aylward wrote:
> "no mass" essentially means "if a photon were to travel at zero
> velocity it would have no mass"

No, it doesn't. "No mass" for a photon means that the norm of a photon's
4-momentum is zero. The mass of any object is the norm of its 4-momentum.

> A photon always at c thus the pop media description "massless" is
> misleading.

No, it isn't. You simply don't know what the word "mass" means and have
misled yourself.

> Mass is any object that has inertia and gravitates. Light does both,
> thus must have mass

That is not what the word "mass" means -- see above. But it is true that:
a) light has inertia in that in the absence of any applied
force it follows a (null) geodesic path through spacetime.
b) light responds to the mass of other objects by following
a (null) geodesic path through spacetime.
c) light generates gravity in that its energy-momentum tensor
contributes to the "source" of spacetime curvature.
These statements also apply to any object with nonzero mass.

> [... further nonsense ignored]

Tom Roberts

On 7/14/22 8:20 AM, Tom Roberts wrote:
> But it is true that:
> a) light has inertia in that in the absence of any applied
> force it follows a (null) geodesic path through spacetime.

I forgot:
a') light has inertia in that it will transfer momentum to
any object it hits.

> b) light responds to the mass of other objects by following
> a (null) geodesic path through spacetime.
> c) light generates gravity in that its energy-momentum tensor
> contributes to the "source" of spacetime curvature.
> These statements also apply to any object with nonzero mass.
>
>> [... further nonsense ignored]
>
> Tom Roberts

On 7/13/22, Kevin Aylward wrote:
> Many are confused on energy.
> All energy is mass in motion. Energy is a real physical object, it is not
> ectoplasm, its mass. All physical real objects must have mass.
> The motion of mass can be rearranged to appear as a physical material
> particle or a physical non material particle.
> Unfortunately, many have the nonsensical view that one can convert one
> substance into another. One can make many things with Lego, but they are all
> plastic.

Did you escape from the same institution as Ross Finlayson?

--
Rich