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No the laws don't break down for massive objects at that speed, they show that you can never GET to that speed, as has already been pointed out.Soul Intent said:Only if the object has a predetermined mass.
No the laws don't break down for massive objects at that speed, they show that you can never GET to that speed, as has already been pointed out.Soul Intent said:Only if the object has a predetermined mass.
Yeah but something like a photon could get to that speed. The only reason a massive object can't accelerate to the speed of light is being it has mass.phinds said:No the laws don't break down for massive objects at that speed, they show that you can never GET to that speed, as has already been pointed out.
Yes. Your point being?Soul Intent said:Yeah but something like a photon could get to that speed. The only reason a massive object can't accelerate to the speed of light is being it has mass.
Monsterboy said:I think you are right , what the OP asked is that , if any object( spacecraft in this case) is accelerated continuously in space without running out of fuel , why can't that object reach or exceed the speed of light ?
I found this when I googled http://physics.about.com/od/relativisticmechanics/f/SpeedofLight.htm
So, according to this link , you can travel at the speed of light but you will need infinite amount of energy to do so.
The universe itself has finite amount of energy (first law of thermodynamics) hence you can't travel at the speed of light.
I hope someone with a background in this subject validates the information in this link.
phinds said:That would better be interpreted as "because there is no such thing as an infinite amount of energy, objects with mass cannot travel at the speed of light".
DaveC426913 said:Agent Smith, this is a misleading argument. It implies that the reason we cannot reach the speed of light is a limitation of the propulsion. This is not so.
Even a "magical" propulsion system that had unlimited thrust, unlimited fuel and unlimited time will never reach c.
In fact, it is the laws of the universe itself that prevent us from reaching the speed of light. The nature of the limit is time dilation.
From post #33?Monsterboy said:So the article i provided is wrong ?
If you mean the article posted just above, the article is right, but you have misunderstood it.Monsterboy said:So the article i provided is wrong ?
Yes ... http://physics.about.com/od/relativisticmechanics/f/SpeedofLight.htmDaveC426913 said:From post #33?
Er... Any specific part?
Slower Than the Speed of Light
The next major set of particles (so far as we know, all of the ones that aren't bosons) move slower than the speed of light. Relativity tells us that it is physically impossible to ever accelerate these particles fast enough to reach the speed of light.
Why is this? It actually amounts to some basic mathematical concepts
Since these objects contain mass, relativity tells us that the equation on the top right of this page determines the kinetic energy of the object, based upon its velocity. Notice the denominator which contains the variablev (for velocity). As the velocity gets closer and closer to the speed of light (c), that v2/C2term will get closer and closer to 1 ... which means that the value of the denominator ("the square root of 1 - v2/C2") will get closer and closer to 0.
As the denominator gets smaller, the energy itself gets larger and larger, approaching infinity. Therefore, when you try to accelerate a particle nearly to the speed of light, it takes more and more energy to do it. Actually accelerating to the speed of light itself would take an infinite amount of energy, which is impossible.
DaveC426913 said:Even a "magical" propulsion system that had unlimited thrust, unlimited fuel and unlimited time will never reach c.
As the denominator gets smaller, the energy itself gets larger and larger, approaching infinity. Therefore, when you try to accelerate a particle nearly to the speed of light, it takes more and more energy to do it. Actually accelerating to the speed of light itself would take an infinite amount of energy, which is impossible.
phinds said:Yes, this says exactly what WE have been saying. If you think otherwise then you are somehow misinterpreting it.
Shouldn't this be the reason for doubt about interpretations of special relativity? At one point we are saying mass is not dependent on velocity because that would make all objects to have no definite mass. Then we turn around and say mass increases with velocity.phinds said:Think about it this way: if mass were actually dependent on speed, then an object would have to have an infinite number of different values for its mass, all at the same time, because it has an infinite number of different speeds, depending on the infinite number of reference frames that one can choose to look at it from. Clearly doesn't work.
I don't have any idea who that "we" is that you are talking about. I'm not aware of any knowledgeable physicists who says any such thing and you will not find any such members of this forum saying so. There are HUNDREDS of threads on this forum pointing out that objects do NOT gain mass in that manner, they gain energy.Neandethal00 said:. Then we turn around and say mass increases with velocity.
rootone said:Since energy and mass are equivalent in relativity, the object's greater energy can be considered as greater mass.
We do that with light because there is no "medium" required for it to propagate through - no "ether". This might not always be the case with other phenomenona.Neandethal00 said:there are 'fish scientists' in the ocean, the fish scientists formulate theories of physics to explain everything to other 'fish' totally ignoring the 'water'.
That's right. This is best demonstrated using a force 4-vector: ##F_μ = γ\frac{∂p_μ}{∂t}##. This implies that the force required to accelerate an object at a constant value tends to infinity over time (for rectilinear motion).Neandethal00 said:My thinking is it is not mass that increases, it is the inertia that increases requiring larger energy to move through space.