Chief Delphi - The speed of light is NOT a constant?! A milestone in Physics?

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Re: The speed of light is NOT a constant?! A milestone in Physics?

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some subatomic particle is lost in the conversion - at the moment I cannot find the equations

This is true as subatomic energies can be represented as particles, but the particles are not protons or neutrons.

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from Wikipedia:

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Then this E could be seen as the energy released or removed, corresponding with a certain amount of mass m which is lost, and which corresponds with the removed heat or light. In those cases, the energy released and removed is equal in quantity to the mass lost, times the speed of light squared....

and if you continue reading and search "binding energy" you will find:

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Because a bound system is at a lower energy level than its unbound constituents, its mass must be less than the total mass of its unbound constituents. For systems with low binding energies, this "lost" mass after binding, may be fractionally small. For systems with high binding energies, however, the missing mass may be an easily measurable fraction.

Since all forms of energy in a system (which has no net momentum) have mass, the question of where the missing mass of the binding energy goes is of interest. The answer is that this mass does not "disappear" into energy (a common misconception); rather, if transformed to heat or light, this mass may move away to another location. The mass "deficit" from binding energy is therefore only mass which has moved. However, it remains mass, because mass is conserved in systems for any given single observer, so long as the system remains closed. Thus, if binding energy mass is transformed into heat, the system must be cooled (the heat removed) before the mass-deficit appears in the cooled system. In that case, the removed heat (which has mass itself when measured in the original inertial frame) represents exactly the mass "deficit."

For example, when two large objects (such as the earth and a meteor) are attracted by a gravitational field and collide, the energy for the heat of impact is extracted from the gravitational field of the objects. However, the system does not lose mass (which represents its binding energy) until this heat is radiated into space, and this space is no longer counted as part of the original system (equivalent to opening the original system).

Closely analogous considerations apply in chemical and nuclear considerations. However, in nuclear reactions, the fraction of mass which may be removed as light or heat, and which then appears as binding energy, is often a much larger fraction of the system mass. This is because nuclear forces are comparatively stronger than other forces.

In nuclear reactions, the "light" which must be radiated to remove binding energy may be in the form of direct gamma radiation. Again, however, no mass-deficit can in theory appear until this radiation has been emitted and is no longer part of the system.

The energy given off during either nuclear fusion or nuclear fission is the difference between the binding energies of the fuel and the fusion or fission products. In practice, this energy may also be calculated from the substantial mass differences between the fuel and products, once evolved heat and radiation have been removed.

Note that M in the equation is not matter, it is mass. The mass converted in a nuclear reaction is from the energy holding the matter of the nucleus together.

Re: The speed of light is NOT a constant?! A milestone in Physics?

Instead of starting a new thread, i'm just giong to pop this question right here as its related to E=mc^2.

What happens to the mass of an object, when it travels @ speed of light?
I tried to search around, but i got multiple-mixed answers.

Re: The speed of light is NOT a constant?! A milestone in Physics?

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Originally Posted by RoboMadi

I remember reading that the mass of an object grows when it approaches the speed of light and becomes infinite(or irrelevant) when it reaches the speed of light.

You can check that though by googling around.

Re: The speed of light is NOT a constant?! A milestone in Physics?

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Originally Posted by RoboMadi

What happens to the mass of an object, when it travels @ speed of light?
I tried to search around, but i got multiple-mixed answers.

The simple answer (as posted above) is that as an object increases in speed, approaching the speed of light, its mass increases, and size is also altered by time/space dilation (the faster you go, the smaller your length).

If it were to reach the speed of light then its mass would be infinite. This must be impossible, right? That would require an infinite amount of energy to accelerate the mass up to that speed!

Ok, now sit down and grab a box of Kleenex incase blood starts gushing from your nose in the next few minutes.

What if, you are converting that mass to energy? what if you are using that same mass in some kind of fusion or matter/antimatter engine? That matter is being converted to energy at the rate of E=MC^2

if the mass of that matter is increasing towards infinity as its speed approaches c, then you will have an infinte amount of mass available to convert in to energy - which is what you need to reach the speed of light.

In fact, not only do you have an infinte amount of energy, you have an infinte amount * C^2

so what does that mean? can you reach the speed of light, by converting the mass to energy as you go? can you go faster than the speed of light, since you will have C^2 * infinitity energy available to you?

Due to space/time dilation, when you reach the speed of light your size will have dilated to zero in the direction of travel, and time will have stopped completely (the the reference frame).

Re: The speed of light is NOT a constant?! A milestone in Physics?

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Originally Posted by thegathering

You can check that though by googling around.

I did and i got multiple answers, as I've mentioned before.
Looking at the fact that its hard to satisfy a geek like me :p .

OK now lets think at two scenarios. Most of the theories we know, by now are really not tested. At least i was not able to find any solid answers; there is still a lot of maybes. But it really doesn't make sense to me.........yes I'm a whinny little kid :p .
If an object travels @ speed of light within an atmosphere, it for sure will burn itself even before catching that speed, plus why one would do such thing.
Now lets look at the second scenario. If an object has to travel @ the speed of light in a vacuum, lets say space, does the mass will act the same as predicted before. Most of the theories have stated that it will be infinite........ Lets think about it once again. If I'm in space and i throw a ball to wards Pluto with the speed of light, there is NO resistance or any kind of friction that will make it lose its mass, or change it in anyway. Most of the people have argued that it will change its shape; but still......how? and why? there is NO resistance.

And yes KenWittlief, my nose will definitely bleed in that kind of a situation. Not to mention that thats the main reason a lot of testing can't be done on this issue. Pretty much there is no way to test it on earth, as one might end up blowing something. Creating that amount of Energy.....just WOW.

But before we go further in where to get the energy to throw a ball @ the speed of light, we must figure out what can/will happen to it and why?

Re: The speed of light is NOT a constant?! A milestone in Physics?

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Originally Posted by RoboMadi

I did and i got multiple answers, as I've mentioned before.

OK now lets think at two scenarios. Most of the theories we know, by now are really not tested. At least i was not able to find any solid answers; there is still a lot of maybes. But it really doesn't make sense to me.........yes I'm a whinny little kid :p .
If an object travels @ speed of light within an atmosphere, it for sure will burn itself even before catching that speed, plus why one would do such thing.

Problem with this scenario is that it's impossible for any matter to obtain the speed of light outside of a vacuum not only because of the heat from friction in the air, but from the friction constantly slowing the object down. It would be like a magnified difference between firing a bullet through the air and firing it underwater. You'd need thrust faster than the speed of light to push you to compensate for the difference caused by friction.

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Now lets look at the second scenario. If an object has to travel @ the speed of light in a vacuum, lets say space, does the mass will act the same as predicted before. Most of the theories have stated that it will be infinite........ Lets think about it once again. If I'm in space and i throw a ball to wards Pluto with the speed of light, there is NO resistance or any kind of friction that will make it lose its mass, or change it in anyway. Most of the people have argued that it will change its shape; but still......how? and why? there is NO resistance.

There is also the (what I call) spagetti theory that the difference in speed (or at that point time) due to acceleration of the ball would stretch matter. (a 100ft rocket ship would stretch to infinite as it approached the SoL boundary)

Re: The speed of light is NOT a constant?! A milestone in Physics?

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Originally Posted by dlavery

OK, so if the speed of light is not a constant, then that means that the speed of other forms of electromagnetic radiation are also not constant. Thus, radar - both emitted and reflected - does not travel at a constant speed. Therefore, radar cannot really be calibrated against a known constant - because there is no known constant.

I think I just found a defense for my next speeding ticket...

-dave

But when you are THAT far over the limit Dave, I'm not sure a minute calibration means too much ;).

Re: The speed of light is NOT a constant?! A milestone in Physics?

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Originally Posted by RoboMadi

RoboMadi,
There is a lot of miss-information out there on this.
A good reference is http://en.wikipedia.org/wiki/Rest_mass
The concept of "relativistic mass" is rather one-dimensional.
It is best to stick with the rest mass and
work out the specific situation at hand.