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View Full Version : The speed limit of light....

marv
07-29-2010, 02:36 PM
Anybody believe it? I don't.

Anybody want to discuss it? I'd like to.

FlaGator
07-29-2010, 02:37 PM
Why don't you believe it?

marv
07-29-2010, 08:03 PM
Einstein maintained that as a body approaches the speed of light, its mass approaches infinity. With an infinite mass, it requires an infinite amount of energy to propel it beyond the speed of light. That's the very simple explanation of his "speed limit".

His error is in confusing gravitational (or rest) mass and inertial (or momentum) mass. Inertial mass is not mass at all, but stored energy. He also forgot about photons.

His own observations of the gravitational bending of light waves disprove his theory. His observations would seem to prove that light cannot travel at the speed of light!

This is not to diminish Einstein's great accomplishments, but even brilliant minds once thought the world to be flat.

Articulate_Ape
07-29-2010, 08:09 PM
That silly Einstein, what a fool.

Sonnabend
07-29-2010, 09:02 PM
Think of it this way

Here it is, the Holy Grail of science where e = mc2.

. <=====

That's it right there. The speed of light. Now relativity states that the closer you approach the speed of light, the more energy becomes mass.

So you get .5 C (where c = lightspeed) to .9 C

And this is where the issue starts. You are standing close to a wall. Take a step closer. Then half that step. then half again. The closer you approach the apex of the acceleration curve , the more energy bleeds off at mass, so what you get at .99999999 C is a tradeoff of energy and mass to almost infinite mass.

What is needed is a burst of energy so intense as to make the tradeoff between energy and mass, to offset the counterbalancing forces

http://www.globalusers.org/relativeng.files/relativity_graph.gif

The energy needed is that of a fair sized star. Not in our lifetimes :(

marv
07-29-2010, 11:31 PM
Think of it this way

Here it is, the Holy Grail of science where e = mc2.

. <=====

That's it right there. The speed of light. Now relativity states that the closer you approach the speed of light, the more energy becomes mass.

So you get .5 C (where c = lightspeed) to .9 C

And this is where the issue starts. You are standing close to a wall. Take a step closer. Then half that step. then half again. The closer you approach the apex of the acceleration curve , the more energy bleeds off at mass, so what you get at .99999999 C is a tradeoff of energy and mass to almost infinite mass.

What is needed is a burst of energy so intense as to make the tradeoff between energy and mass, to offset the counterbalancing forces

http://www.globalusers.org/relativeng.files/relativity_graph.gif

The energy needed is that of a fair sized star. Not in our lifetimes :(
The problem is that this argument says that not even photons (the particle of light) cannot even travel at the speed of light.

Some physicists say that photons have no rest mass. Some say that photons acquire rest mass when only in motion (the conversion of inertial mass to rest mass?). Still others claim, as I do, that photons do have rest mass. But no matter which you chose, Einstein observed the curving of light from a distant star during a total eclipse when the star was still behind the eclipsed sun. Only particles with rest mass can be affected by gravity, in this case the photons being affected by the gravity of the sun.

The quandary then becomes how much energy is needed to propel that photon at its "speed of light" if its mass, no matter how acquired, has now become infinite? Einstein says it must be infinite, but I don't think he thought this through.

BTW, my disclaimer: I am not a physicist, just a humble school dropout who reads a lot.

Articulate_Ape
07-30-2010, 01:00 PM
The problem is that this argument says that not even photons (the particle of light) cannot even travel at the speed of light.

Some physicists say that photons have no rest mass. Some say that photons acquire rest mass when only in motion (the conversion of inertial mass to rest mass?). Still others claim, as I do, that photons do have rest mass. But no matter which you chose, Einstein observed the curving of light from a distant star during a total eclipse when the star was still behind the eclipsed sun. Only particles with rest mass can be affected by gravity, in this case the photons being affected by the gravity of the sun.

The quandary then becomes how much energy is needed to propel that photon at its "speed of light" if its mass, no matter how acquired, has now become infinite? Einstein says it must be infinite, but I don't think he thought this through.

BTW, my disclaimer: I am not a physicist, just a humble school dropout who reads a lot.

Gravitational and inertial mass are, in fact, the same; a physical fact confirmed by, eg, the Eötvös experiment, which tested the Equivalence Principle (which can be framed as a statement that inertial and gravitational mass are the same). Also, photons are have no mass, which is precisely why they travel at the speed of light (which massive items cannot, because it takes an infinite amount of kinetic energy added to the object to get it to light speed; this behaves in some sense like getting an infinite mass, because energy has mass). Light is bent by gravity not because photons have mass, but because the gravitational field curves space itself, and photons (like everything else) travel in space.

marv
07-30-2010, 05:53 PM
Gravitational and inertial mass are, in fact, the same; a physical fact confirmed by, eg, the Eötvös experiment, which tested the Equivalence Principle (which can be framed as a statement that inertial and gravitational mass are the same).
False. Consider a 55 grain .22 (.223) bullet fired from a rifle. A 55 grain bullet weighs .12595 ounces at rest. But when fired at 3000 feet per second, it has the inertial mass of 1097.8 pounds. Obviously, that 55 grain bullet does NOT weigh 1097.8 pounds. Therefore gravitational mass and inertial mass are not the same. Rest and inertial mass each have their own unique properties and characteristics, but they are not the same.

Also, photons are have no mass, which is precisely why they travel at the speed of light (which massive items cannot, because it takes an infinite amount of kinetic energy added to the object to get it to light speed; this behaves in some sense like getting an infinite mass, because energy has mass).
If you have to claim that rest and inertial mass are the same, you contradict yourself as Einstein did, which leads to an incorrect conclusion.

Light is bent by gravity not because photons have mass, but because the gravitational field curves space itself, and photons (like everything else) travel in space.
I give no credence to that tired two dimentional "trampoline space-time" example used to describe a three dimentional space.

Articulate_Ape
07-30-2010, 06:41 PM
False. Consider a 55 grain .22 (.223) bullet fired from a rifle. A 55 grain bullet weighs .12595 ounces at rest. But when fired at 3000 feet per second, it has the inertial mass of 1097.8 pounds. Obviously, that 55 grain bullet does NOT weigh 1097.8 pounds. Therefore gravitational mass and inertial mass are not the same. Rest and inertial mass each have their own unique properties and characteristics, but they are not the same.

Energy has mass. The energy need to propel the bullet (i.e. the cartridge load) is added to the mass of the bullet. The finite distance the bullet can travel is dictated by the energy available to propel it and the effect of gravity on that mass. You have essentially backed the E=mc2 formula by this example.

If you have to claim that rest and inertial mass are the same, you contradict yourself as Einstein did, which leads to an incorrect conclusion.

The mass of the matter (i.e. bullet) is the same at rest as in motion. The mass added by the energy has less impact at low velocities. If you fix a rifle upon a tripod so that the bullet in the chamber is precisely 6' off a perfectly level plane and also fixed bullet of the same mass and at the same elevation to an apparatus that would drop it the moment the rifle's trigger is pulled, both bullets would hit the ground (i.e. plane's surface) at precisely the same time.

I give no credence to that tired two dimentional "trampoline space-time" example used to describe a three dimentional space.

The gravitational effect on space has been proven by observation of that effect.

But, I guess I'll have to take your word over that of a good friend of mine at Cornell who happens to have a PhD in physics. I don't know WHAT I was thinking.

SarasotaRepub
07-30-2010, 10:44 PM
Easy guys, keep it friendly. I don't want to have to Force Choke anyone tonight... ;):D

Articulate_Ape
07-30-2010, 10:48 PM
Easy guys, keep it friendly. I don't want to have to Force Choke anyone tonight... ;):D

http://i531.photobucket.com/albums/dd359/JamesSavant/LOSTME.jpg

Sonnabend
07-30-2010, 11:07 PM
Either way, whatever drive can or could be considered, what is needed is a power source at least 200 years away from us. Like owning a Ferrari and having a cat to pull it..

Articulate_Ape
07-30-2010, 11:11 PM
Either way, whatever drive can or could be considered, what is needed is a power source at least 200 years away from us. Like owning a Ferrari and having a cat to pull it..

True that.

Gingersnap
07-30-2010, 11:17 PM
Easy guys, keep it friendly. I don't want to have to Force Choke anyone tonight... ;):D

Yeah, these theoretical physics discussions alway seem to get out of hand. The shouting, the punching, the spilled beer - it's disgraceful. :p

Big Guy
07-30-2010, 11:20 PM
My thoughts;

http://www.youtube.com/watch?v=4Gj8bin3vlQ

Articulate_Ape
07-30-2010, 11:57 PM
My thoughts;

My carefully considered rebuttal:

http://www.youtube.com/watch?v=qVE60zwXx1k

Big Guy
07-31-2010, 12:04 AM
My carefully considered rebuttal:

http://www.youtube.com/watch?v=qVE60zwXx1k

You are a sick Bastard. :eek::D:D

Articulate_Ape
07-31-2010, 12:09 AM
What. :D