Freke1
23rd October 2006 - 02:35 PM
QUOTE (NeoDude+Oct 16 2006, 04:35 AM)
Light is not affected by gravity because it has mass. It is affected by gravity due to the fact that is travelling through a mass-induced-curved space-time. Or something.
Does this mean that a straight line in space-time bends too? Lets say You shine a flash into space - if You are unlucky with the positions of the masses You might illuminate Your own behind. Just wondering!
besttech01
25th October 2006 - 03:37 AM
Light cannot escape a black hole's gravitational field..
bigjbird82
25th October 2006 - 05:27 PM
Light has to have mass that is why it is classified as having particle and wavelike characteristics (dual wave particle theory). the particles of the light do have a mass. which is also why if light is shined (in a vacume) toward a wheel the wheel will rotate. i forget what this experiment is called or who did it but it is true. and it can bend because of this.
AlphaNumeric
25th October 2006 - 05:45 PM
Having momentum is not the same as having rest mass. The photon has momentum but no rest mass.
bigjbird82
25th October 2006 - 06:03 PM
it does have particles whch is considered to be energy which in the e=mass times the speed of light squared. therfore light does have mass but it is a type called realitivistic mass which can be argued upon but the fact does stand that light does have mass.
Zephir
25th October 2006 - 09:42 PM
QUOTE (AlphaNumeric+Oct 25 2006, 08:45 PM)
Having momentum is not the same as having rest mass.
Having rest mass in not the same as having mass.
AlphaNumeric
25th October 2006 - 09:49 PM
That doesn't mean you can replace the p in E^2 = (mc^2)^2 + (pc)^2 because the m in that equation IS rest mass.
If you're going to start talking about photon relativistic mass you have to make sure you're replacing the right things in equations with the correct equivalents or you end up mixing up rest and relativistic masses, as you did if you think you replace p with mc in E^2 = (mc^2)^2 + (pc)^2 .
bigjbird82
25th October 2006 - 10:29 PM
OH, ok I see what you are saying.
but the question is then still does light have mass?
i will do some reserch and get back on tomarow with experiments and theorys to prove weather or not it really does have mass.
dyosh
19th November 2006 - 12:30 AM
but momentum is a force and can't a force only be exerted on something with a mass
VertCoach
10th May 2007 - 11:42 AM
dyosh has a point, though wether you can really jump higher in the dark is probably something we shouldn't be worried too much about. No use in jumping high if no one can see you!
Precursor562
10th May 2007 - 03:39 PM
QUOTE
is there any particle with less mass than a light particle
If the graviton particle exists then it would most likely be smaller than a photon.
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