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Thread: does light have a gravitational effect?

  1. #1 does light have a gravitational effect? 
    Forum Senior Booms's Avatar
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    Gravity affects light (see black holes) is this because of the Wave-Particle duality of light? photon packets have mass, and therefore can be affected by mass


    does this then mean these photon packets have their own gravitational influence? and how great is it? (microscopic I'm assuming, if all the mass of earth only exerts 9.81Mps a single photon is probably not even going to register)



    BONUS QUESTIONS

    A. how far is the reach of gravity, I know it lessens with distance, but is there a point where the gravitational pull of any object becomes 0, or does every atom in the universe slightly affect every other atom in the universe?.


    B. Could gravity affect non-material particles? (tachyons, dark matter etc)


    C. why does the W-P duality exist? if light is affected by gravity, surely this grounds it as having a mass, regardless of wave-like qualities.


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  3. #2 Re: does light have a gravitational effect? 
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    Quote Originally Posted by Booms
    Gravity affects light (see black holes) is this because of the Wave-Particle duality of light? photon packets have mass, and therefore can be affected by mass
    Light has energy, not mass, and yes, gravity acts on light.

    Quote Originally Posted by Booms
    does this then mean these photon packets have their own gravitational influence? and how great is it? (microscopic I'm assuming, if all the mass of earth only exerts 9.81Mps a single photon is probably not even going to register)
    Yes.

    Quote Originally Posted by Booms
    A. how far is the reach of gravity, I know it lessens with distance, but is there a point where the gravitational pull of any object becomes 0, or does every atom in the universe slightly affect every other atom in the universe?.
    Never zero, it's an ass.

    Quote Originally Posted by Booms
    B. Could gravity affect non-material particles? (tachyons, dark matter etc)
    Yip.

    Quote Originally Posted by Booms
    C. why does the W-P duality exist? if light is affected by gravity, surely this grounds it as having a mass, regardless of wave-like qualities.
    Because light can behave as a particle and a wave. Energy and mass are two of the same. Don't you read anything on this forum?

    Your riding the Donkey with a carrot on the end of a branch


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    Although a photon of light has zero rest mass, it also has a momentum which is easily calculated. Gravitational lensing is usually associated with Einstein's General Relativity but a similar effect is predictable from Newtonian gravitation. Interestingly, the angle of deflection derived from using Newtonian notions of gravitation is exactly half that predicted by General Relativity.

    In relativity, the path of a photon is subject to the constraint that the space-time interval between the events of its emission and reception is zero, i.e., ds = 0. This is a very odd result. It implies that when you look at a star in the sky, the space-time distance between the event of light being emitted from the star and the event of you seeing it is exactly zero, even when the star is light years away. When space-time is curved, as it is assumed to be close to massive objects, the shortest path will be a curve rather than what we would otherwise consider to be a straight line. So the massive object will bend the ray of light.
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    Light--of nearly any physical manifestation, certainly has energy density, tension or pressure, as well as momentum. See the Wiki on "stress energy tensor", and "Kumar" mass. The bookkeeping value we always see for the mass of light, as zero, is just that, an entry in a table that enbles equations to be developed about the real things.

    The intrinsic mass of quantized electromagnetic radiation, and how it affects the curvature of space, and how the curvature of space acts back upon it, is a function of energy density, tension, and momentum, and solutions to these equations do not obtain values of zero intrinsic mass.

    There are mythologies that develop, even within the educated community, and massless light is one of them.
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  6. #5  
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    Simply put. Yes

    They have energy which means it has equivalent mass as given by E =mc^2 (squared)

    Light can twist the spacetime continuum as a result giving it a very small fractional gravitational field.
    "If you wish to make an apple pie from scratch, you must first invent the universe". - Carl Sagan
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    Quote Originally Posted by Quantime
    Simply put. Yes

    They have energy which means it has equivalent mass as given by E =mc^2 (squared)

    Light can twist the spacetime continuum as a result giving it a very small fractional gravitational field.
    Good thing that. Then it's obvious it can't escape a black holes schwarschild radius while gravitons can.
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    Gravitons aren't proven to exist yet. Even if they do they are massless and as a result must be energyless as given by E=mc^2.

    Perhaps the reason that it does not get pulled into a black hole and photons do. There can be much speculation about that.
    "If you wish to make an apple pie from scratch, you must first invent the universe". - Carl Sagan
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    Quote Originally Posted by Quantime
    Gravitons aren't proven to exist yet. Even if they do they are massless and as a result must be energyless as given by E=mc^2.

    Perhaps the reason that it does not get pulled into a black hole and photons do. There can be much speculation about that.
    Shouldn't gravitons have negative energy, I mean they drag the mass closer to rest speed, don't they? Shouldn't that give them less mass actually? since the mass in the black holes doesn't seem totally infinite?
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  10. #9  
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    Quote Originally Posted by LeavingQuietly
    Quote Originally Posted by Quantime
    Simply put. Yes

    They have energy which means it has equivalent mass as given by E =mc^2 (squared)

    Light can twist the spacetime continuum as a result giving it a very small fractional gravitational field.
    Good thing that. Then it's obvious it can't escape a black holes schwarschild radius while gravitons can.
    Actually, gravitons can't.

    You are making an error that is common among laymen when it comes to gravitons.

    Gravitons are to gravity as photons are to the electromagnetic force. So just as photons are quanta of electromagnetic radiation, gravitons are quanta of gravitational radiation.

    And just like the electromagnetic force is mediated by virtual photons, the gravitational force is meditated by virtual gravitons. So while gravitons and photons cannot escape a black hole's event horizon, their virtual counterparts still mediate their respective forces. Not only do black holes have gravity, but they can have an electric charge, and the electrostatic force that goes along with it.

    One way to look at it is that photons and gravitons carry information about changes in their respective fields. So when a mass shrinks inside its event horizon, any further information about changes in its field cannot get out. So the only information anyone outside the field knows is from just before the mass falls inside the event horizon. The gravity field is "frozen" in the state it was in at that instant. This is why black holes were sometimes called "frozen stars".
    "Men are apt to mistake the strength of their feelings for the strength of their argument.
    The heated mind resents the chill touch & relentless scrutiny of logic"-W.E. Gladstone


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  11. #10  
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    Quote Originally Posted by Quantime
    Gravitons aren't proven to exist yet. Even if they do they are massless and as a result must be energyless as given by E=mc^2.
    E=mc˛ is a only a special case equation only valid for objects with a rest mass (It can't even be used for photons). The general formula which also works for "massless" particles is:



    Where p is momentum. Both photons and gravitons have momentum, so they both have energy.
    "Men are apt to mistake the strength of their feelings for the strength of their argument.
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  12. #11  
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    Quote Originally Posted by LeavingQuietly
    Quote Originally Posted by Quantime
    Gravitons aren't proven to exist yet. Even if they do they are massless and as a result must be energyless as given by E=mc^2.

    Perhaps the reason that it does not get pulled into a black hole and photons do. There can be much speculation about that.
    Shouldn't gravitons have negative energy, I mean they drag the mass closer to rest speed, don't they? Shouldn't that give them less mass actually? since the mass in the black holes doesn't seem totally infinite?
    Lets think about this one.

    I haven't got a model for gravitons because I don't believe they exist. I never believed that gravity is a quantum effect because it is a very prominent force in the macro universe and isn't really bound by many quantum rules.

    If it is negative energy then it has negative mass as given by the equation E=mc^2..... That means that it can have a negative gravitation field in which mass and energy in this universe would be repelled by this negative mass and energy.

    Only if there were an equal force of negative mass and 'positive' mass equally acting on some matter would that matter reach rest speed. In which case I think may be impossible because positive mass is everywhere in the universe and it would be knocking the poor negative mass around the shop anyway.

    Even if you timelocked a particle it would still remain relative to the universe and its velocity. By removing speed and wanting rest speed that creates a huge problem because what you are suggesting is removing every dimension from that particle all the way down to the 3rd dimension. Basically severing it from ALL 4th, 5th 6th dimensions. Not only would it have no time, or alternate or paralell, it would be completley dead and void.


    I'm not sure how gravitons can have negative energy because they were created 'supposedly' from positive mass simply exisitng and twisting the spacetime continuum to create a spacetime field.

    This is what I mean leaving quietly, the 'gravitons' are products of spacetime, gravitons themselves create ripples in spacetime if they are from the mass of the gravitaional field, which means that they carry with them the force that pulls objects towards that source of gravity.

    Which means that they are pulling objects towards the source of the gravitaional field. If they had negative energy and brought objects to rest speed the force of gravity would not exist.

    I am theorising here because I do not understand what you mean by rest velocity.

    Its best not to use black holes to model behaviour in this universe because black holes aren't the same space as our space, nor do the rules of physics hold true beyond the event horizon.

    If you want to create something with rest speed, isolate a vaccuum that repels all known matter from the universe , create a body that will create 'positive' gravity (anything in our universe that has mass) then create an object that has negative mass, which actually takes mass away from something (maybe a Higgs boson repelling device or something).

    OK I've got it:


    Positive mass = Planet, Star, Black hole
    Neutral mass = Photon, gluon (that rings a bell with why they travel at 1c)
    Negative mass = Negative planet, negative star, negative black hole.

    Here's a mind boggler. Maybe light travels at rest speed and the whole universe travels at 1c

    The negative mass would in my most wildest fantasy be the Anti-Higgs boson. Now even anti-protons and positrons have regular what you would call 'Positive Higgs Bosons.

    That would suggest that there is a Positive Pro and Anti Universe here. And also a pro and anti universe of negative matter wihtin the same spacetime as us but unobservable because of that.

    It probably exists all around us this negative mass which causes rest speed, except it wouldnt cause rest speed at all, it would be moving our mass around without any idea where the gravitational effect is coming from because although the negative mass is effecting our mass in the universe, it itself is equally being distrubed by our positive mass....

    Why exactly do you want rest speed anyway? I am interested where this is going.


    PS. That was all spontaneous theorising, do with it what you will. I'll have forgotten it by tonight after a few bevvies :wink:
    "If you wish to make an apple pie from scratch, you must first invent the universe". - Carl Sagan
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  13. #12  
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    Quote Originally Posted by Quantime

    Lets think about this one.

    I haven't got a model for gravitons because I don't believe they exist. I never believed that gravity is a quantum effect because it is a very prominent force in the macro universe and isn't really bound by many quantum rules.
    That's not a very persuasive argument. Electromagnetism is very prominent in the macro universe, and it's quantization has resulted in the most accurate theory ever produced in Quantum Electrodynamics.
    "Men are apt to mistake the strength of their feelings for the strength of their argument.
    The heated mind resents the chill touch & relentless scrutiny of logic"-W.E. Gladstone


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  14. #13  
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    It is. I was talking about gravity however.
    "If you wish to make an apple pie from scratch, you must first invent the universe". - Carl Sagan
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    sorry, I couldn't see my post.
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    Quote Originally Posted by Quantime
    Gravitons aren't proven to exist yet. Even if they do they are massless and as a result must be energyless as given by E=mc^2.

    Perhaps the reason that it does not get pulled into a black hole and photons do. There can be much speculation about that.
    So all solely attractive forces have zero or negative mass in their interacting particles?
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  17. #16 For the negative mass! 
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    Quote Originally Posted by Quantime

    Positive mass = Planet, Star, Black hole
    Neutral mass = Photon, gluon (that rings a bell with why they travel at 1c)
    Negative mass = Negative planet, negative star, negative black hole.

    Here's a mind boggler. Maybe light travels at rest speed and the whole universe travels at 1c

    The negative mass would in my most wildest fantasy be the Anti-Higgs boson. Now even anti-protons and positrons have regular what you would call 'Positive Higgs Bosons.

    That would suggest that there is a Positive Pro and Anti Universe here. And also a pro and anti universe of negative matter wihtin the same spacetime as us but unobservable because of that.

    It probably exists all around us this negative mass which causes rest speed, except it wouldnt cause rest speed at all, it would be moving our mass around without any idea where the gravitational effect is coming from because although the negative mass is effecting our mass in the universe, it itself is equally being distrubed by our positive mass....
    For the negative mass!
    http://www.thescienceforum.com/Dark-...%21-21177t.php


    Quote Originally Posted by icarus2
    1-3)The law of motion of negative mass and negative mass

    ----------

    - m1 ------ - m2
    fig03. Ngative mass - m1 and negative mass - m2 (initial velocity =0, m1>0, m2> 0)









    In this case, momentum conservation is valid.




    , because, let's view to the acceleration term.
    , is opposite direction(spherical coordinate +r direction). So, velocity direction is opposite direction.

    In the spherical coordinate

    In the rectangular coordinate



    Negative mass and negative mass: Both two objects are accelerated in the direction of + r which extends distance r, so as time passes, the distance between them is greater than initially given condition, and the force between them is attraction, but the effect is repulsive.

    The force is attraction(-Gm1m2/r^2), thus the potential energy between them has negative value.

    If negative mass and positive mass were born together at the beginning of universe, positive mass has attractive effect each other, so it forms star and galaxy structure now, but negative mass has repulsive effect each other, so they cannot make massive mass structure like star or galaxy.

    =========
    Hypothesis of Dark Matter and Dark Energy with Negative Mass :
    http://vixra.org/abs/0907.0015
    If negative mass and positive mass were born together at the beginning of universe, positive mass has attractive effect each other, so it forms star and galaxy structure now, but negative mass has repulsive effect each other, so they cannot make massive mass structure like star or galaxy.

    http://www.thescienceforum.com/Dark-...%21-21177t.php
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    If gravity brings matter closer to rest velocity, their mass will decrease according to relativity and relativistic mass.

    That's what I get. Back to the question: if a force is solely positive, does its thought transporting particles have negative or zero mass?
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    Posts are getting bent in here, and the forum is getting hush-hushed because I can't see my posts or anything new for that matter, how many get that?
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  20. #19  
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    Quote Originally Posted by LeavingQuietly
    Quote Originally Posted by Quantime
    Gravitons aren't proven to exist yet. Even if they do they are massless and as a result must be energyless as given by E=mc^2.

    Perhaps the reason that it does not get pulled into a black hole and photons do. There can be much speculation about that.
    So all solely attractive forces have zero or negative mass in their interacting particles?
    Not neccisarily, W & Z bosons the guage bosons and interaction carrying particles for the weak nuclear force have mass.

    The gluon (strong nuclear force mediator) and the photon (electromagnetic mediator) don't have mass, but they have a relative mass given by their energy. The equation for that was provided by Janus earlier on. This one:



    Don't forget that all forces aren't always attractive. To electrons the electromagnetic force of the proton can repel.

    If gravity brings matter closer to rest velocity, their mass will decrease according to relativity and relativistic mass.
    How can gravity bring matter closer to rest velocity? Gravity is a curvature in the sapcetime continuum. A combination of the 3rd and 4th dimension. If there was no speed for anything there could be no time, thus gravity would not exist. What you are stating is paradoxical.

    If you create a model to explain that paradox by all means it won't be paradoxical, i just don't see where this is going.

    I get the feeling what you are saying is that velocity of a particle creates mass. Photons travel at the speed of light and go past stars and they don't have mass when they do pass them.

    It may be true, according to my model of physics particles vibrate at certain positions and oscillate in various dimensions not neccisarily at the same time, but can give the impression of mass. I suppose it would be theorectical if you could break down the vibration (speed if you will) to disable it having any effect on our dimension, thus omiiting its velocity, and making it at 'rest'.

    Doing that however would stop the particle from even exisiting (actually being observeable in this universe). Still unable to Quantify any result from it as effect.

    Posts are getting bent in here, and the forum is getting hush-hushed because I can't see my posts or anything new for that matter, how many get that?
    I never get that. The only explanation is deletion of your posts perhaps.

    To be frank, this entire thread is entirley theoretical hog wash to which I don't understand. Its all very hypothetical. I wouldn't class it as pseudo science because there is some verifable logical deductions that can be made, however I must know....

    What are you asking about rest velocity for? What purpose does it suit? Do you want to remove mass? Do you want to go beyond the speed of light? Is this a time travel theory?

    I admire and praise your theory, it would be nice to know if it has a purpose however.
    "If you wish to make an apple pie from scratch, you must first invent the universe". - Carl Sagan
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    This is not a theory, it's a question.

    Rest mass is mass moving at a velocity zero.

    This does not defy logic; there must be a rest velocity in order for einsteins special relativity theory to work. A related argument is that we move through space in a velocity. So we must know for a fact that there is a still system thereby, no matter how little a given mass we are comparing with.

    Q.E.D. Mass at rest is less then one traveling in relativistic speed.

    {Planets travel slower the bigger they are. You deny that?
    {Mass decrease the slower it moves

    Q.E.D gravitons carry negative or zero mass.
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  22. #21  
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    Quote Originally Posted by LeavingQuietly
    This is not a theory, it's a question.
    An incredible theoretical one.


    Rest mass is mass moving at a velocity zero.
    Relativley speaking, I am sat at my computer with very little motion. Relative to the earth I have velocity zero. There is a big differernce between that and saying a particle has no velocity at all all on its own.

    This does not defy logic; there must be a rest velocity in order for einsteins special relativity theory to work.
    Yes, objects in the universe move however and all are moving at different velocities to one another. If an object did have zero velocity you could never say that it was totally still relatively to yourself because when using special relativity you use other objects to give a relative perception of events (lightning and the moving train for instance)


    A related argument is that we move through space in a velocity. So we must know for a fact that there is a still system thereby, no matter how little a given mass we are comparing with.
    Where is this still system then? Mass does not govern velocity as mass is only interactive with other particles in as so far as the strength of gravity, which compared to the other 3 known fundemental forces of the universe is very weak.

    Q.E.D. Mass at rest is less then one traveling in relativistic speed.
    Don't get QED on me, I've theorised more on this stuff to know that there will never be a QED, not as long as I exist.

    Yes mass is less at much lower than relativistic speeds, only relative to outside observors though, we have no proof that relative to anyone travelling at relativistic speeds this holds true.

    {Planets travel slower the bigger they are. You deny that?
    Don't imply I mean that unless I explicity say "planets don't travel slower the bigger they are". If you check, I never said anything of the sort. Never quote something I haven't said to swing favour to your side of the discussion.

    Planets don't travel slower the bigger they are, NOW I deny it. Black holes are massive and they move faster than the earth. Some don't.

    What does mass have to do with slowing things down? Timewise maybe with gravitational time dilation, that is however a different effect.

    {Mass decrease the slower it moves)
    If it is travelling at close to relativistic speeds yes. At ordinary speeds no.

    Q.E.D gravitons carry negative or zero mass.
    I'll discuss that if and when gravitons are proven to exist, negative mass to be proven to exist. Right now thats like saying a new colour makes this colour when it is mixed with blue. We can't tell until we get the new colour.
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    Quote Originally Posted by Quantime
    Quote Originally Posted by LeavingQuietly
    Q.E.D gravitons carry negative or zero mass.
    I'll discuss that if and when gravitons are proven to exist, negative mass to be proven to exist. Right now thats like saying a new colour makes this colour when it is mixed with blue. We can't tell until we get the new colour.
    Basically you can, but it's true what you're saying, we need to have evidence for it being the truth.

    Basically, if it was true, gravity fields would be lower at high velocities, since it wouldn't put masses landing on it closer to rest speed.
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