# Light and Time Dilation?

G

#### Guest

One of the many things that bothers me is this...

If matter begins to cause the effect of time dilation the faster it gets (ie time surrounding goes by relatively faster) Then how come this does not apply to light and EM in general?

This would then mean from an outside point of view the speeding object is actually relatively slowing down the faster it gets!! Of course, light travels at c, but there mustn't be any time dilation as the light does not 'slow down' to us. Is this simply because light is an energy wave and not matter?

And what about gravity, I wonder? This is something I have *never* read or heard of being discussed or explained - Do the effects of gravity take place instantaneously across a distance, or does the effect of gravity travel at c also?

For instance, let's assume the sun and it's matter suddenly disappeared (Casting aside all unlikeliness for a minute), so now there is next to zero mass where the sun once was.

If gravity *does* abide by staying at the universal 'speed limit' of c, this would mean that not only would it take 8 minutes for us to see the sun vanish but also 8 minutes until the Earth suddenly would lose the feel of the sun's gravity and slingshot linearly off into space?

Whether or not c limits gravity forces as well, obviously this speed is the key to much, if not all of the universe's scientific secrets, the famous equation Energy=mass*lightspeed^2 being a classic example.

-Raze

Wonderful questions! No one will take this on - as far as modern physicists go. They all tell us that light is both a particle and a wave. It can be either one or the other, but not both. It is as if light makes the "choice" as to what it will be when we try to test for waves or particles (there is no way to test for both). Like you, I feel that this sort of thing hides a fundamental problem that "they" are having with general or special relativity. Again, you are dead right about the time effect. We are told that light is "massless" and that this is why it can race up to "c" and not face the same constraints as ordinary matter. Seems like an inadequate answer.

In answer to your question about gravity's effects being limited by "c", the answer is it is not. Steal the sun, and the earth immediately spins off on its own. The only way physicists can explain this is what they call "action at a distance." I'll translate the phrase: "We have no clue as to why we assign a speed limit to even 'massless' particles and yet gavity can thumb its nose at the speed limit and at us."

You pose great questions. My guess is that the "Ether" must be resurrected. The Ether - as an unseen fabric upon which all propagates. Tug one end of this fabric and you immediately effect the distant edge.

Yeah, that light being matter and a wave confused me heaps back in highschool... You see it as either a photon or an EM wave -- But surely, it can only be one!!

This gravity thing is really interesting... I actually thought it must be under the 'c speed limit', but like you said, this really does make us have to re-consider the existance of an 'ether' of some sort!

Well this being the case, it does go to show that effects can take place instantaneously over a distance. So since gravity is instant, does this imply gravity is not exactly a 'wave'? You often hear reference to gravity 'waves', ie as a means of vehichle propulsion. Maybe 'wave' isn't an entirely accurate term...

Well, this must open the door to the possibility of connecting two separate points of space/time instantaneously somehow (Not having to 'wait' for one point to affect another).

I'm thinking a 'wormhole' is probably *not* exactly the way to go about it (in the sense of connecting two singularities), rather we may have to go about it some entirely different way. It just seems hardly practical, or possible to open and maintain something based on the anatomy of a black hole, and safely pass matter through. But then again, maybe it can be done...

-Raze

"If matter begins to cause the effect of time dilation the faster it gets (ie time surrounding goes by relatively faster) Then how come this does not apply to light and EM in general?"

It is important to remember that it is not matter that is causing time dilation, but the speed of travel. If you were riding on a photon, time for you would be unchanged. However, if you obseved clocks at a different location they would appear to be slowing down.

"And what about gravity, I wonder? This is something I have *never* read or heard of being discussed or explained - Do the effects of gravity take place instantaneously across a distance, or does the effect of gravity travel at c also?"

Albert Einstein ask this same question. He answered this with the general theory of relativity.

Dear all,

I have an idea that might answer the questions, but it requires some time to learn the theory of that idea in order to observe how I came the conclusions as to how gravity, and other physical components of the universe work. Let us begin...

(pi)r^2=1/4(pi)r^2*4

=4<1/4(pi)r^2>

=1(pi)r^2

=(pi)r^2, also

=2<1/4(pi)r^2>2<1/4(pi)r^2>

Now=2<1/4(pi)r^2>2<4/(pi)r^2> if second set of quadrants have a reverse time component that is joined in conjunction with the first set of quadrants in the x,y,z gragh that have a positive time component.

2<1/4(pi)r^2>2<4/(pi)r^2>

=4<1/4(pi)r^2><4/(pi)r^2>

=4(1)

=4

...Therfore, the correct answer is infinity^4/4 as revolution approaches 360 degrees.

Please feel free to double check the math. I have not described the context that this math is based on. But I will be transmitting a full description of the context so that you may see step for step how I built the mathematical description. I will include in this work, graphs, and proofs to support each item. This will show that if one accelerates along a straight path to arrive at a point on that line that is located at a position on that line that is four times an infinite length along that line, the point will be located exactly at the point at which the person started from. I already have the graghical proofs that prove this, I am now converting those proofs into mathematical statements to describe these proofs. Also, this particular version is non-relativistic; But, purely mathematical. If we added the elements of time dialation that are associated with the suerluminal velocities that would be present in actual physical representations of these kinds of models at work(if such were possible), then a reverse time component would occurr at a point short of an infinite distance along the path. This would change the outcome of the final entity from some intertial frames, but the initial proof should remain conserved in at least one of the inertial frames due to the independant time components at each of the inertial frame. I will have to do the math to see what the actual outcome of this model is in terms of relativity....then I will post the results.

Regards

Edwin G. Schasteen

I will post more...but please feel free to critique. But note: there is much to the idea that I am describing above, therefore the above post is not complete. I will continue to post more and will draw the conclusion of how the universe works during the forecoming posts.

Best Regards,

EGS

C does not limit gravity as gravity is in a catagory all by itself.

C is corospondant to what frequency realm that particular light packet is assigned to.

C is only slowed or speededup by the structure of the universe and the forces that m exerts.

I read somewhere recently that supposedly the speed 'c' has slightly changed in the universe (or this part of it anyway), although I'm not sure if that is literally what was meant.

The speed of light mustn't travel at c for its own sake, surely there is some relatively unknown aspect that governs this (ie an 'ether' or something along the lines of what we interpret as one?)

Just like when an object falls from a great height (e.g a skydiver) it will accelarate to a certain speed and then reach terminal velocity, in other words the fastest that object can be pulled through the atmosphere by gravity alone due to air friction. Of course if there were no air, a skydiver would continue accelarating at what is it .. 9.8ms^2? Until it hits the surface (hits not lands -- He tried opening his chute but there was no air for it to drag with *l*)

-Raze

Great questions, some stuff there that would take years of study to learn about... but I can try and make comments...

Light speed is indeed an important quantity. But it is misleading to think of photons 'accelerating' up to c . Rather, view it this way: things with no mass *must* go at c, they cannot, by the rules of the universe, go any slower. Thing with mass, on lthe other hand, must always move at v < c , never faster.

Take care when you think about time dilation. It takes a lot of careful math to figure out which quantities are which, and in which reference frames. Velocity is different in different inertial reference frames.

The gravitational force is propagated at the speed of light. Look up 'graviton' to learn about the theory. No spooky action at a distance here.

C is not the only physical constant, though. Much more important to our daily lives is the fine structure constant. A small change in that would make the Universe uninhabitable.

Have you heard of Bob Lazar? That guy who supposedly worked at the S-4 installation at Papoose Lake Nevada, back in 1988-89?

Whether you beleive his story about reverse-engineering a recovered ET vehichle or not, what he has to say is often quite credible and interesting.

One thing that caught my interest is how he has said that gravity is not only a wave, but actually part of the EM spectrum that we have not dealt with. To be honest, I didn't know what to think of this at first (and I'm still not sure either!) Gravity is quite a different thing to EM radiation altogether. It arguably IS a wave, but...

What you said makes perfect sense about particles of no mass being able to meet the universal speed limit of c without accelaration and time dilation. After all, both these things are related to mass which in this case is not involved.

Of course the existance of photons and gravitons is debated and I am not quite sure myself where my belief stands. I myself have always beleived the theory that a photon is not a particle as such, but rather a small energy packet released which gives off EM radiation in the visible light spectrum.

As for gravity, I've always stuck to the idea that gravity's similarities with matter of any kind exist only with the mass that causes gravity, and other parts of space/time that are influenced by that force. I beleive the force of gravity itself manifests in a way common present-day science cannot yet grasp.

-Raze

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I also recommend reading the research information on
"The The Light Cone"
an illuminating introduction to relativity
Website: http://www.phy.syr.edu/courses/modules/LIGHTCONE
Email:<[email protected]>

http://www.phy.syr.edu/courses/modules/LIGHTCONE/pics/lightcone-sm.jpg
These documents comprise an elementary introduction to the Theory of Relativity. The intended audience is a class of nonscience undergraduates in (PHY 105) Science for the 21st Century a course offered by the Department of Physics at Syracuse University. (Eventually, these documents will be expanded to include more technical explanations for more advanced audiences.)

Admittedly, this is an ambitious plan to explain the Theory of Relativity in three one-hour lectures. Comments and criticisms are welcome. Rob Salgado ([email protected])

Spacetime, The Theory of Relativity is really a physical theory about time and space. In fact, it actually says that there is no such thing as time and there is no such thing as space. Instead, it is a theory of "a new thing called Spacetime". Spacetime is the history of an entire universe, that is, the set of all of the events that happened in that universe.
Our plan is to follow a pseudo-historical development of how we came to understand "Spacetime", the spacetime of General Relativity. We do so by considering a sequence of models for spacetime. Each model represents "how we understood space and time" at various stages in our human history. Specifically, we will consider:

Aristotle's view
Galileo's view
Einstein's view
Each model recovers the notions of "space" and "time" in slightly (but quite significantly) different ways. At issue:

How is the nature of space and of time to be viewed?

"Absolutely" ("Universally", "Publicly")
<or>
"Relatively" ("Personally", "Privately")
???

"It is not philosophy, but physical experiment, that decides which one models the real world best. Indeed, it has been our gradual understanding of the Laws of Physics that has forced us to replace one model with another."

Causal Structure and the Light Cone
In general, a causal structure provides each event in spacetime its own notion of ordering events into "those events to its past", "those events in its present", and "those events to its future". Each model for spacetime has a different causal structure.
At the root of Einstein's Spacetime is a particular causal structure. Unfortunately, the nature of the causal structure of Spacetime and its (experimentally verified) consequences are often beyond our everyday experience. Hence, it may appear quite counterintuitive. This is the source of much of the confusion in this subject.

The Light Cone is a mathematical model that very neatly encodes this causal structure of Einstein's Spacetime. Each event in Spacetime has a double-cone attached to it, where the vertex (i.e., the tip) corresponds to the event itself. By convention, "time" runs vertically in all of our diagrams. The upward-directed cone opens to enclose the directions pointing towards events to the future of this event. The downward-directed cone directions pointing towards events to the past of this event.

In my opinion, understanding the Light Cone is an important first step towards understanding the Theory of Relativity. (Some mathematics is a necessary crutch to clarify and correct our physical intuition.)

Flat and Curved Spacetimes
An important second step will be understanding how the Light Cones are arranged throughout Spacetime.

If the Light Cones are arranged in a neat grid in a uniform manner, we say that "Spacetime is flat". The spacetime of Special Relativity is a flat spacetime.

If the Light Cones are arranged in a non-uniform manner, we say that "Spacetime is curved". The spacetime of General Relativity is generally a curved spacetime.

Einstein's Theory of Gravity relates the curvature of Spacetime to the presence of matter. As an interesting example, we will consider the Spacetime around a Black Hole.

Credit where credit is due
The causal past:
This presentation of the spacetime-models is heavily based on Geroch (General Relativity from A to B, which was based on a course for nonscience undergraduates). The presentation of the Schwarzschild black hole is based on Geroch and on Ellis/Williams (Flat and Curved Space-Times)

The causal future:
The next planned revision of these web documents will include "Track-2" material. In particular, I will try to further develop "Galilean geometry" and "Minkowski geometry" based on Yaglom (A Simple Non-Euclidean Geometry and Its Physical Basis.) and introduce "4-vectors and -tensors", with much inspiration from Burke (Spacetime, Geometry, Cosmology) and (Applied Differential Geometry). For now, follow the "Technical Comments" links for the Track 2 material.
Of course, I am solely responsible for any errors in the contents of these documents.

Below are additional references on "The Light Cone"
http://www.phy.syr.edu/courses/modules/LIGHTCONE/references.html
<hr size="1" width="80%" color="#000099" align="left">"Everything you know,...is Wrong!
soon we shall all discover the truth."
http://profiles.yahoo.com/vosstech

I have done lots of research in that area and have many of my own theories. I will tell you what I think. What is time exactly? Time is the speed at which events occur. Since all events and reactions can only occur in the presence of energy in the form of light, light is essentially "time". The speed of light determines the speed at which reactions and movement occur. If light were accelerated to 100 times the speed of light, matter would receive photons 100 times as fast, therefore reactions would occur 100 times as fast, and therefore time would be passing 100 times as fast. That would make it the carrier of time, and thus technically immune to its effects. Time dilation has to do much with this concept. It occurs when you start catching up to the photons of light. Imagine a stream of photons in space, travelling at 300,000 km/s. If you are moving at 1/2 the speed of light, relatively the speed of light has slowed to 50 percent for you. (Speed of light)-(Your Speed)=(relative speed of light(time))

About gravity, gravity has been shown to affect light, bending it or pulling it in. Therefore, it must be faster than light, in order to guide it the way it does. I think research is pointing to the speed of gravity being about 310 times the speed of light. The inexplicable effect of electron tunneling occurs at this speed, and scientists were able to send light at that speed through a cesium chamber. I think it is the most probable answer for now.

Interesting concept... But what you're saying is that time can only be present where there's light? There are places where there is practically zero light (I experienced this for myself once on a school camp, going deep down in a long, windy cave, at night so there was no ambient light whatsoever. And man, that was blacker than black)... But despite any light, time still flows.

As for the relative velocity of ourself compared to a light stream (e.g your example of travelling at half the speed of light in the same direction as the actual light) Doesn't relativity come to the conclusion that no matter how fast we travel, light from a relatively stationary object is still at c relative to us?

I myself donot believe in photons as such (Unless a photon is seen as an energy packet that releases EM as visible light instead of a particle).

If light is photon particles of zero mass travelling at light speed, we must remember that light is merely part of the whole EM spectrum that our eyes respond to, this would mean the whole EM spectrum, even microwaves are particles of some kind too.
Of course this contradicts because EM is an energy wave, not a particle of any kind! The only photons I believe exist are the car model.

Of course there are kinds of nuclear radiation (alpha, beta but not gamma) that are particles travelling at extremely fast speeds (but not as fast as c). If I recall correctly one is an electron and the other is a hydrogen or helium particle. However alpha and beta do not fall under the EM spectrum because of the fact they are particles, but the term radiation still applies because of the'yre overall nature and how they are the by-product of a nuclear reaction. Only gamma is an actual EM wave.

-Raze

More interesting stuff. I don't understand what you think is the difference between a photon and an energy packet. That's pretty much the definition of a photon - a quantum of energy in the form of an oscillating electric and magnetic wave. Your statement that EM is an energy wave and not a particle is only half correct. Quantum Mechanics teaches us that all particles are also waves, and all waves can be looked at as particles. I mean, if an electron is wavelike, then any EM frequency can be looked at as particlelike. There are some really neat experiments thaat you can do to show this.

And just a note: time dilation effects go like \gamma=(1-(v/c)^2)^(1/2) (hate that ascii math notation), not just linearly. Here v is the relative velocity of what you're looking at, and \gamma tells you how much slower their time is going than yours. Light always travels at c relative to you, no matter what its source.

Onomato' I am for you, I must touch you.

The locus lines of transets A. to B.

One beam of light is passed from points A to B.However must transend a distance, that takes this light beam, close to the outside of the edge of this galixy.

If the time clock starts at zero and transends the time necessary for the beam of light to travel hundreds of thousands of light years,is a delay of time ever realized, since the lenz effect bends the light away.

This would be away from the course this beam would have taken, if no galixy were there.

Light at time, light at distance.

You forgot to say, C at relative values in m modified, or the structure of the universe, of which we only are looking through one frequency.

I am for Onomato, please I must touch him.

>One of the many things that
>bothers me is this...
>
>If matter begins to cause the
>effect of time dilation the
>faster it gets (ie time
>surrounding goes by relatively faster)
>Then how come this does
>not apply to light and
>EM in general?

Time dilation occurs because with an increase in speed you increase the energy of an object. By increasing the kinetic energy you increase the total energy, and therefore increase the equivalent mass of the object. This increases the curvature of surrounding space-time (the key equation of GR basically just says mass is proportional to curvature). If you increase curvature, time passes more slowly. The photon is a massless particle, and therefore does not affect curvature, hence no time dilation.

>And what about gravity, I wonder?
>This is something I have
>being discussed or explained -
>Do the effects of gravity
>take place instantaneously across a
>distance, or does the effect
>of gravity travel at c
>also?
>
>For instance, let's assume the sun
>and it's matter suddenly disappeared
>(Casting aside all unlikeliness for
>a minute), so now there
>is next to zero mass
>where the sun once was.
>
>
>If gravity *does* abide by staying
>at the universal 'speed limit'
>of c, this would mean
>that not only would it
>take 8 minutes for us
>to see the sun vanish
>but also 8 minutes until
>the Earth suddenly would lose
>the feel of the sun's
>gravity and slingshot linearly off
>into space?
>
>Whether or not c limits gravity
>forces as well, obviously this
>speed is the key to
>much, if not all of
>the universe's scientific secrets, the
>famous equation Energy=mass*lightspeed^2 being a
>classic example.

Gravity does propagate at c. Technically we don't orbit the sun, but the position that the sun was in 8 minutes ago (if the sun is 8 light-minutes from the earth, I don't remember if that is the correct figure). So we would continue to orbit the sun for 8 minutes even though it wasn't there anymore

Here's a thought:
Suppose you were in a spaceship that could reach 99.99% of the speed of light, and flew towards the sun at maximum speed. The sun's gravitational pull is 28 times that of earth. As you fall towards the star at 99.99% of the speed of light, you will be further accelerated by the gravity at a rate of 274 m/s^2. Since mass is irrelevant to gravity, the ship would be accelerated torwards the star no matter how much mass and energy it accumulated. Using the constant acceleration of an external gravity source, would it be possible to achieve or even excede the speed of light?

Nah, you can't accelerate faster than light. Trust me, it works out that gravity doesn't give a _constant_ acceleration in some reference frame outside of the ship-sun system. Rather, the gravitational field comtributes to the overall energy of the ship, and this can only lie below infinity, thus v<c.

Creedo, I really don't understand you. Something about gravity bending light? I don't see what you're saying. SOmething about the variability of c in matter? I could talk about that...

Before the period.

He she'always like to come to the studio dressed in a blue pastel, to match her blue eyes, however her hair was bright red.

Her hair was long on one side,short on the other and would always in some fashionb of motion, slosh against the microphone.

The other musicians did not care, as they were either eating,or tuning their insturments.

There was a recording to beand they had better not scrw this one up; a lot of money was involved..

>No' the measure could come after the whole note is played.

So what we have, say for example with the group Supertramp, is a blending of a saxiphonal values, right into the value of the vocal song!

So what that value acts as, is a clair within vocal and harmonic ranges.

This is why Supertramp so pld coppies, on their first cut, like they were going out of stile.

Tonnal range, is,--- harmioc value? It's just you have to look at the quality of variance vibration, which in the platten of what is being played?

"I hate this alarm clock"! I can never figure out how to turn it off, alarm clock is tossed in the trash, by the bedside, only to be used naother day>M is universe, however m in universe, as it sits, is stringed.

So therfor one can not really express the equation E=mc2, as m in cosmi modified, is some particles, but is also expressed as matter-particle force.

So with the factors of acceleration in m+, or cosmi altered state by accel now realized, light as light is an expression of joules by force, or presure.This factor is corospondant to the structure of m+, or the structure of the universe, as realized modified?

So from transient points from A. to B., C always contracts to the locus for gravity, as exerted on any similar force and matter.

eg light bends!?

Give a little bit of your light tome.
Give a little bii-a'it, give a little bit of your love to me.

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