Americans Discover Time Travel

[Indio no.9]

Also light has little to no mass. Pushing things something with mass up to a 1% speed, say a solar system, must be alot of energy. If we could find a way to remove the orbital energy from a small amount of mass could we keep the energy and send the mass in whatever direction?

No because you see light is not made up of phisical particles, they are waves, but unlike normal waves they dont need particals to vibrate in order to travel. Otherwise they wouldn't travel from the sun to the eart due to the fact that theres nothing there.

[Meh]

Then why is light responsive to gravity?

[Indio no.9]

umm its not. And if you have any evidence that says it is id like to hear it.

[Meh]

Now if someone from the USA had said that you would be all like "your schools do suck over there".

http://www.iam.ubc.ca/~newbury/lenses/research.html

[Indio no.9]

No your schools still suck. You see over here we do maths and over there you do math, that Meh is because we do more than one sum. (we usually get passed the 1+1 solution and go on to harder stuff)

[Meh]

Your evading the issue.

An insult is not the way to accept new knowledge.

I am wrong lots of times.

Learn to suck it up.

Is light effected by gravity?

[The Hunter]

Light IS responisve to gravitey, evidence: Black holes... So much gravity is even sttracts light. (And "Sucks" it up).

So yes, light has a mass...

[Mitch]

the researchers noticed some spinning gray fog in the sky over the pole on January 27 which they believed to be just ordinary sandstorm.

Lot of sand in Antartica, ey? It's like the sandy desert of the ice.

Time travel happens all the time. We're all stuck in a loop of someone elses time travling accident. He died in the past and is reborn in the future only to die again in the past...

[kroner]

fact: all forms of energy have both the inertial and gravitational properties of mass of their equivalent amount of matter. in other words, all forms of energy are responsive to gravity and exert gravity, and can have momentum (inertial properties).

technically light has mass of zero, but it has momentum proportional to its energy (E/c, I think, but I don't remember exactly).

[ephiroll]

And for something to really blow your mind, look up the "membrane theory" of the birth of the universe...I'm still having problems getting my head around that one, it's a new theory that will probly replace the "big bang" theory in a few years as the accepted way that the universe was created.

Membrane theory is basically been disproved. Each time they come up with a model the field effects cannot be detected. Tehn they revise the model so that it would be harder to detect. And then it is still not detected.

If membrane theory has been disproved it's been within the last two months because as of two months ago (lastest info I have on the subject) the membrane theory was very viable and about to kick the big bang's butt (over the years the big bang theory has been "tweeked" to include all the info we have until it's gotten to the point that people are starting to realize that it doesn't really fit with what we now know). New discovery's are pointing to the big bang as being impossible, because for the universe to have been created by the big bang then at some point in the past things would have to had moved FTL, but there is no evidence of any energy source that could have caused it.

Membrane theory explains the creation of the universe without causing any problems with relativity (the universe would have been created in "waves" and the FTL rule remains unbroken). The membrane theory also gives an explantion as to where all the "darkmatter" in the universe is, so far we can only observe 1/3 of what is in the universe, the other 2/3 is there because we can see it's effects on things (galaxies wouldn't hold together if they consisted of only their visible mass) but is completly undetectable to every instrument that humans have used to observe the cosmos with so far.

But, in 2020 a very important experiment should be completed. That experiment involves satillites that are searching for "gravity waves", which Einstein predicted, but til now are unproven to exist. Wether gravity waves exist or not will basically prove or disprove that the big bang theory or the membrane theory is correct. Gravity waves=big bang (inflation), no gravity waves=membrane theory (ekpyrosis).

Adn I just want to point out that it's been known for almost a century now that light is affected by gravity. It was proved by observing a star with a known position and then observing it during a solar eclipse, there was a very noticable difference in the stars position.

Light doesn't really have a clear cut distinction anyway, light is photons (so light does have mass, although it's so close to zero that it may as well not, but that small amount of mass is why gravity affects it) yet light acts as a wave and the exact reason it's able to travel through a vacum is not fully understood.

[kroner]

no, light has no mass. it has momentum and is effected by gravity (the properties of mass), but it has no rest mass and therefore no mass. if it did, its energy content and relativistic mass would both be infinite.

[ephiroll]

Okay, I as wrong in saying that light is affected by gravity because of it's mass, I looked some things up and I know what I got confused now. Here is something interesting I found while looking for my mistake.


Does light have mass?

by Philip Gibbs

The short answer is "no", but it is a qualified "no" because there are odd ways of interpreting the question which could justify the answer "yes".

Light is composed of photons so we could ask if the photon has mass. The answer is then definitely "no": The photon is a massless particle. According to theory it has energy and momentum but no mass and this is confirmed by experiment to within strict limits. Even before it was known that light is composed of photons it was known that light carries momentum and will exert a pressure on a surface. This is not evidence that it has mass since momentum can exist without mass.

Sometimes people like to say that the photon does have mass because a photon has energy E = hf where h is Planck's constant and f is the frequency of the photon. Energy, they say, is equivalent to mass according to Einstein's famous formula E = mc2. They also say that a photon has momentum and momentum is related to mass p = mv. What they are talking about is "relativistic mass", an outdated concept which is best avoided. Relativistic mass is a measure of the energy E of a particle which changes with velocity. By convention relativistic mass is not usually called the mass of a particle in contemporary physics so it is wrong to say the photon has mass in this way. But you can say that the photon has relativistic mass if you really want to. In modern terminology the mass of an object is its invariant mass which is zero for a photon.

If we now return to the question "Does light have mass?" this can be taken to mean different things if the light is moving freely or trapped in a container. The definition of the invariant mass of an object is m = sqrt{E2/c4 - p2/c2}. By this definition a beam of light, is massless like the photons it is composed of. However, if light is trapped in a box with perfect mirrors so the photons are continually reflected back and forth in the box, then the total momentum is zero in the boxes frame of reference but the energy is not. Therefore the light adds a small contribution to the mass of the box. This could be measured - in principle at least - either by an increase in inertia when the box is slowly accelerated or by an increase in its gravitational pull. You might say that the light in the box has mass but it would be more correct to say that the light contributes to the total mass of the box of light. You should not use this to justify the statement that light has mass in general.

It might be thought that it would be better to regard the relativistic mass as the actual mass of photons and light, instead of invariant mass. We could then consistently talk about the light having mass independently of whether or not it is contained. If relativistic mass is used for all objects then mass is conserved and the mass of an object is the sum of the masses of its part. However, modern usage defines mass as the invariant mass of an object mainly because the invariant mass is more useful when doing any kind of calculation. In this case mass is not conserved and the mass of an object is not the sum of the masses of its parts. For example the mass of a box of light is more than the mass of the box and the sum of the masses of the photons (the latter being zero). Relativistic mass is equivalent to energy so it is a redundant concept. In the modern view mass is not equivalent to energy. It is just that part of the energy of a body which is not kinetic energy. Mass is independent of velocity whereas energy is not.

Let's try to phrase this another way. What is the meaning of the equation E=mc2? You can interpret it to mean that energy is the same thing as mass except for a conversion factor equal to the square of the speed of light. Then wherever there is mass there is energy and wherever there is energy there is mass. In that case photons have mass but we call it relativistic mass. Another way to use Einstein's equation would be to keep mass and energy as separate and use it as an equation which applies when mass is converted in energy or energy is converted to mass as in nuclear reactions. The mass is then independent of velocity and is closer to the old Newtonian concept. In that case only total of energy and mass would be conserved but it seems better to try to keep conservation of energy. The interpretation most widely used is a compromise in which mass is invariant and always has energy so that total energy is conserved but kinetic energy and radiation does not have mass. The distinction is purely a matter of semantic convention.

Sometimes people ask "If light has no mass how can it be deflected by the gravity of a star?" One answer is that any particles such as photons of light, move along geodesics in general relativity and the path they follow is independent of their mass. The deflection of star-light by the sun was first measured by Arthur Eddington in 1919. The result was consistent with the predictions of general relativity and inconsistent with the Newtonian theory. Another answer is that the light has energy and momentum which couples to gravity. The energy-momentum 4-vector of a particle, rather than its mass, is the gravitational analogue of electric charge. The corresponding analogue of electric current is the energy-momentum stress tensor which appears in the gravitational field equations of general relativity. A massless particle can have energy E and momentum p because mass is related to these by the equation m2 = E2/c4 - p2/c2 which is zero for a photon because E = pc for massless radiation. The energy and momentum of light also generates curvature of space-time so according to theory it can attract objects gravitationally. This effect is far too weak to have been measured. The gravitational effect of photons does not have any cosmological effects either (except perhaps in the first instant after the big bang). There are far too few with too little energy to make up any noticeable proportion of dark matter.

[Meh]

ephiroll - OK. There have been experiments on membrane theory over the years and they have failed. They then tweak membrane theory. Any experiment is a good experiment. I prefer to stay with inertial experiments. The longer I stay at rest the longer I want to be a rest.

kroner - Yeah. It's when I get off the simple concepts like mass is mass that I don't quite remember the rules. So what is the explaination for our 1% light speed not having any measurable effect? Because I don't get that either.

[new.vogue.nightmare]

*head explodes*

[new.vogue.nightmare]

It is possible that out time awareness is skewed since we are travelling near 1% of the speed of light.

speed of light c = ~299'792 k/s

speed of sun around galatic core = ~220 k/s

This is not to mention and speed the whole galaxy may have. I don't know if that is know. It is hard to measure since you only know the realtive speed of everything else and the fact that much of the observed speed is not speed but rather more universe being created between two points.

Another thing I'm not clear on is that if we are already travelling at at least 1% the speed of light does that mean there is a direction in which light can only travel the remaining 99% of the speed. They would have figured that out long ago if there was.

Also light has little to no mass. Pushing things something with mass up to a 1% speed, say a solar system, must be alot of energy. If we could find a way to remove the orbital energy from a small amount of mass could we keep the energy and send the mass in whatever direction?

There's alot of this I just don't understand anymore if I ever really did understand it.

Of course, that's only our time awareness between us and the locations we use as a point of reference, since all motion is relative to a point assumed to be stationary. Different points of reference mean different rates of movemnt.