Think about it: If light had mass...

x(

That would be wierd.

Without using some sort of handwavium cheat, that is. :o :crazy:

Then I never would have been born to go back in time and kill my Grandfather. :silly: Or something.

paradoxes can be paradoctored.

(Professor, to Fry): "Oho, a lesson in not changing history from Mr. I'm My Own Grandfather!!"

Where an 1g-accelerating elevator is indistinguishable from a Earth mass? Doesn't the experimenter shine a light beam on the wall, and it bends downward due to the accleration/"gravity"?

(this memory is from 20 years ago, so I'm obviously confused. Can you set me straight?)

we would be equally dead.

if barbara bush's ass had less mass, she'd STILL be a disturbingly ugly cow.

I need a cockpunch smiley. I already posted and everything.

...but too late, sucka!

:thumbsup:

:bounce:

nt

9.1093826 × 10?31 kg / electron =
0.00000000000000000000000000091093826 g

Question
How does gravity alter the trajectory of light?

Answer
According to Einstein's General Relativity Theory,light will be affected in the same way matter is affected by gravity. This is because under this theory, we should think of gravity not in terms of vector like forces, but as a consequence of the "shape" of the universe.

From Newton's point of view, gravity was a linearly directed force with which all objects with mass pulled on all other objects with mass. His analysis showed that the strength of the force was proportional to the product of the 2 masses attracting one another, and inversely proportional to the square of the distance between them. Thus an apple and the earth would pull toward each other, and the apple "falls" from the tree. Since light (whether perceived as a ray or a photon) has no mass, Newton's equation predicts that it will not be attracted by gravity towards anything, no matter how massive.

In order to construct a theoretical framework that would be consistent to all observers and that did not rely on some independent fixed reference frame, Einstein had to discard this perception of how gravity works and devise a new understanding. According to this theory, all object with mass alter the curvature of spacetime, the 4 dimensional fabric of the universe. Objects moving through spacetime then simply follow the curves that have been created.

http://www.physlink.com/Education/AskExperts/ae661.cfm

Thats a true statement, a box confining photons through use of perfect mirrors would have more mass with photons in it. Light undeniably has relatavistic mass. Further, it has momentum and can impart momentum to that which it strikes.

So it depends what the definition of "mass" is.

which have REAL mass and cannot travel at the speed of light.

Clinton's testimony?

:P

:rofl:

...(m)ass...

Poster with batchelor's degree in physics (i.e. me) says photons do not have mass.

"Does light have mass?", his answer was (after a pause) "It has no rest-mass."

Is that true?

As an object increases its speed, it mass becomes 1 / (1 - (v / c)^2) times greater, where v is its velocity. You can see that when v = c, the coefficient becomes infinite, which is why nothing else can travel that fast.

Photons can do it precisely because they have zero rest mass, so their relativistic mass becomes 0 * (1 / 0) which is a bit of a mathematical grey area. ;)

(not my opinion--Paris Hilton's)

:rofl: