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Re: Einstein Was Right - It Has Been Measured And Found To Be True.

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Posted by Thed/">Thed on June 23, 1998 04:43:41 UTC

: : : Formula is : : : Energy=Mass*MassSpeed2 : : : C is Materialspeed. : : : C is not light speed.

: : : : There is one major problem with this. If the mass is not moving it has no energy, if it is moving backwards it will have negative energy. This is blatantly wrong.

: I think your not looking at the formula. The speed of the object we are talking about is in regard to a certain origin that we have deemed to be standing still when compared to us. Even if the speed is negative, relative to our origin, the formula squares it, making it positive.

Joe

First off, apoogies if this gets long winded and covers what you know already and sounds snotty. My style of writing has been criticised before for being didactic, pedantic and "superior sounding", it is not to be.

You are tight in saying that Human I. Scientists formula is always positive but that does not make it any more correct. The problem is, as you say, in defining a point of origin to measure the speed (velocity) against. In physics this is a problem of frames of reference and is one of the underlying principles that led to Relativity.

Look at it this way. let us say you are in a room and have a ball in your hand. You define the origin to be yourself and the ball has zero speed. By the equation above E=m*0^2 = 0. So the ball has no energy. Now let us consider an observor stationary with respect to the Earths rotation. He defines the point of origin to be himself, he is stationary, and the Earth rotates at several hundred hundred kilometers an hour. (Can't remember the value but lets assume 300 Km/h). In this frame of reference the ball has a speed of several hundred Km/h. By above E=m*300^2=900,000 units. Quite obviously 900,000 !=0. But it gets worse. Let us consider an observor stationary with respect to the Earths rotation around the Sun. In this frame of reference the speed of the ball is thousands of kilometers per hour and E ~ 3,000,000 units of energy. Now let us consider an observor stationary with respect to the Suns motion through the Galaxy. In this frame the Ball has a speed of hundreds of kilometers per _second_ and E ~ 10,000,000,000,000 units. Let us consider an observor stationary with respect to the Galaxies rotation. In this frame the ball has a speed of thousands of kilometers per second and E ~ 1,000,000,000,000,000 units of energy.

I'll admit my figures are probably a little out but the point is that depending on the frame you choose the speed of the ball is different and so the energy is different. Who measures the correct speed and the correct energy?

This is the classical Newtonian way of doing things where the speed of object is assumed to be relative to some fixed point in space. Basically there is assumed to be an observor who is stationary with respect to the universe and he can measure the absolute speed of anything.

How does this relate to light speed? If we measure the speed of light in a lab we can take our point of origin to be the Sun. So we measure the speed of light c, to be the speed in the lab v plus the speed of the Earth around the sun u. c=u+v. 6 months later the Earth is going in the opposite direction around the sun and the speed of light is c=u-v. All you need do is measure the speed of light every day for a few years and you will see a pattern where the speed changes by a factor of u every 6 months. Two guys called Michelson and Morley done this and they measured the speed of light to be c, and only ever c. It did not change depending on the Earths position and speed. Hence, the speed of light is constant independant of the observor. This then leads us to E=Mc^2 where the energy of an object depends on a constant and not a variable that depends on an arbitrary choose of coordinates.

So, the only constant is light speed.

:And your wrong about measuring the speed of light.

How so? Please provides cites, references, papers in physics journals and any other evidence that 100 years of Physics is wrong.

:When they : realized that they had the technology to try to measure the speed of light, which they believed to be the same no matter what, they attempted to try to do it.

Minor historical note. It was originally thought the speed of light was variable. It was generally believed that light travelled in the Aether which was a massless material of infinite tensile stress permeating the universe. Michelson and Morley set out to measure the properties of the Aether. They did not believe (at first) that the speed of light was a constant. The result was rather shocking when it was found as it went against all accepted Physics in the day.

:I don't understand it very well myself, but I'll do my best to explain it to you.

Not a problem. The background to this is not easy to understand at the best of times.

:We know that we are moving through the universe (Possibly not, it might revolve around us)

If the Universe moves around us then we are Special in some way. The whole point behind Einsteins ideas is that there is no Special observor, everyhting is Relative. The precepts behind Relativity and Cosmology is that the Universe is Homogeneous and Isotropic, the same wherever you are and looks the same to all observors.

:They found that light had the same speed "going :east or west". And : here is where the Theory of Relativity is :taking over and I don't really understand it.

Perfectly correct. The trick is to realise that the frame of reference you choose is arbitrary and you can define a set of rules (Lorentz Ttransformations) that explain differences in how people see things. The only thing that is constant is the speed of light. This leads to the rather daft idea that time and space are also relative concepts that depend on your frame of reference, your speed if you will.

: I hope some people who are more knowledgeable, and better spellers, can shed some more light on this.

Bad pun, really bad pun.

Now let us consider a real problem that was tackled. Let us say that you are travelling at the speed of light and have a torch. You turn the torch on and point it in the direction you are travelling. What speed does the light from the torch come out at? The speed of light or twice the speed of light?

To help understand this first consider a simpler problem. Take a man (observor O) sitting beside a railway track when a train goes past. In a train carriage is another man (observor O1) who turns a light on. This light travels out from the light bulb and hits the ends of the carriage at the same time, assuming the light bulb was in the middle of the carriage.

For the man outside the carriage sees the light goes on but as the light wave moves out the train is moving forward with velocity v. So the light hits the front of the carriage in time c-v and the back of the carriage at time c+v. It hits the back of the carriage first in other words. But according to the guy in the carriage it hits both ends at the same time! This is a paradox as both people measure something completely different for the same event. To solve the paradox _assume_ the speed of light is a constant and construct a transformation that allows both people to agree on the same thing. I'll point out that if you do not assume light speed is constant both people can never agree on the same thing.

I am deliberately missing out the maths as it gets a little hairy if you have not done vector calculus, 3 and 4 vector transformations and a healthy dose of Newtonian physics.

At this point I'll stop lecturing, don the flame proof armour and arm myself with a BFG!

  • Set of lecture notes on transforms, frames and Relativity for the sado-masochistic.

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