Speed of Light

[Cheeto]

How is it considered that anything with mass cannot acheive the speed of light, or break it?

How does galaxies moving away from each other faster than light not considered an object of mass breaking the speed of light?

A galaxy definitely has mass, and its definitely moving through space faster than light driven by dark(Unkown) energy. So why do these two seem to contradict eachother, yet both considered truth? Am i missing or not understanding something?

When first heard, i figured it had something to do with atoms breaking down at the speed of light, but have read nothing stating that.

Just as dark energy is forcing the galaxies to accelerate which have acheived faster than light and still speeding up, why could you not assume that a rocket you built could travel faster than light given enough time and energy? Surely if theres no problem of break down of atoms and there is no friction than there would be a caculatable energy required to get an object to travel faster than light, being that something with mass(Galaxy) is already abserved to do so by not infinite energy, surely theres even a limit to dark energy, its got to run out sometime or be converted to other forms of energy.

 

[The Traveler]

When you speed up your mass increases, with every increase of mass more energy is needed to go faster, the more energy you put in for speed the more mass you get. You probably get my drift.

So when nearing the speed of light you need enormous amounts of energy to get faster and every time you get a bit nearer to the speed of light you need exponentially more energy, in the end you can get nearer to the speed of light but never break it because of the ever increasing amount of energy needed to go just a tad faster.


On to the galaxies that seperate from each other faster then light:

To state it simply: both galaxies originated from the same point of origin (the big bang) and each moves away from that point of origin at a near light speed. However, both are moving away in an exact different direction. So the galaxies still move below light speed away from their point of origin but relative to eachother they move at almost twice the speed of light.


I hope this clears things up a bit.


Kind regards,

The Traveler

 

[Cheeto]

Wow! Thanx.

Its i missleading statement then, looking from there start point, only looking at one galaxy, it does not travel faster than light.

 

[The Traveler]

Its i missleading statement then, looking from there start point, only looking at one galaxy, it does not travel faster than light.

Well, it's true that they move away from eachother faster then light but seperately they don't move away faster as light from their point of origin. A bit confusing but both are right to say so.

 

[Cheeto]

Yes i get it. Like two cars traveling away from each other, each car going 60mph = them moving away from each other at 120mph.

I also now understand the can't break light thing, some what. I understand that the mass gain and energy needed equal out kinda, as in the object will just gain more mass and need that extra energy. But what i don't understand now is how does an object moving near light speed cause it to gain mass, where is it getting the mass from. To my understanding you need atoms, or atleast particals added to gain mass, so whats going on there causeing the object to gain mass?

 

[The Traveler]

When you add more energy to increase speed this energy is stored into the object as mass. All this according to the famous E=mc2.


(shamelessly copied from this source)
Well, actually, it's mass is governed by the "gamma" equation. Gamma (γ) is equal to the inverse of the square root of the difference between c2 and the square of the object's velocity:

γ = 1/√(c2-v2)

If you always express velocity (v) as a fraction of the speed of light (for example, 0.1c), then the equation simplifies to this:

γ = 1/√(1-v2)

For an object going 0.1c, gamma is 1.00503782.

An object's mass in motion is equal to its mass at rest multiplied by its gamma. A 10-kg ball moving at 0.1c would then have a mass of 10.0503782 kg. A 10-kg ball moving at 0.9c would have a mass of nearly 23 kg.


Kind regards,

The Traveler

 

[polytrip]

Although everything stated above is true, it is possible for galaxies to move faster then the speed of light.

The speed of light is defined as the speed at wich a photon moves through empty space.
The rule does not apply to space itself.

Space itself can expand at every speed. And the expansion of the universe is mostly the expansion of empty space.

The accumulation of this effect over large distances, wich is exactly what the traveler described above, makes it possible for objects to be seen as moving faster then the speed of light, but the total expansion of the universe makes it possible to see the boundaries of space move faster then the speed of light from any imaginary fixed point of the universe as well. As long as the distance to that point is great enough.

So this takes us to the question on what space is made of. Showing that the original question is a very good question since it directly leads to the greatest mystery in the known universe.

 

[Cheeto]

i have a better understanding now of light speed, thanx Traveler.


Why wouldn't everyone consider that space is expanding at near the spead of light, since its actually true. Like in the example above, two cars moving away from each other at 60mph = them moving away from each other at 120, but you could not say either car is going 120mph, because its not true of course. So to say that space expands faster than light is bad wording, because it leads people to thinking that space actually can move faster than light, when truly its only going near speed of light, which is very common.