Originally Posted by SCollins
Originally Posted by lordikon
What has less mass than a photon (which has no rest mass)?
Its been proven photons have mass, about 20 years ago actually.
Small things are able to move faster because E=mc^2, anything with a rest mass (m, in this formula) will need infinite energy to move the speed of light, so only things with no rest mass may travel the speed of light.
massive assumption on their part, it just worked for what they needed it to.
patently aware of the speed of light, what it is and how it has been treated as a unproven constant
Of course, it's possible scientists are currently wrong, but there is no evidence of anything travelling faster than light so far.
scientists have been wrong for a long time, how do you observe things which travel faster then your data collection abilitys ?
I've yet to see any evidence that photons have mass (rest mass). It's not known for sure that they're absolutely massless, but if there aren't then there would be issues with the math.
E=mc^2 is a scientific theory, not an "assumption". There's a huge difference, as a scientific theory, in this case, has thousands of predictions that it has gotten correct and many attempts to verify it have all proven correct. Light is actually a proven constant thus far, unless you have some evidence to the contrary.
I'm open to the things you're talking about, if you're willing to provide some evidence.
Originally Posted by Stilldawn
Sorry to jump in here but I have a stupid question that just burns in my brain regarding this time dilation etc stuff, mainly directed at lordikon, and others in the know regarding physics.
You say a few pages back about the 4 year travel to alpha at near the speed of light, saying that the traveler would experience 4 days, yet earth would experience 4 years...
My question is regarding the aging part... Are you telling me that the cells/organs/whatever in the bodies of the travelers would only age 4 days, while the bodies of those on earth would age 4 years... So expanding the example, say we take a trip near the speed of light and experience 40 days of travel, 20 days there and 20 days back to earth... When we arrive on earth will the travelers look 40 days older (so not noticeably older) and would the people on earth look 40 years older (grey hair, deaths, births, childhoods, etc included)?
That's what I don't get lol.
Yes, the cells and atoms in the bodies of the travelers would only age a few days while the people on Earth's would age 4+ years. The things that cause aging (and the passage of time) would actually slow down. If you and a friend were 20 years old and you left on a near speed of light round trip for 40 days (for the travelers), when you got back to Earth your friend would see you as 20 years and 40 days old, and your friend would be 60 years and 0 days old.Edited by lordikon - 11/12/12 at 7:48pm