Does gravity have mass?

[inocente]

My, my, comptemptuous as well. Well, every dog to his bone. I can’t judge his " theory " since those things are admittely beyond my kin. But he had a PhD in Astrophysics and was employed in the field for some time. And since I don’t understand the physics and math of the various modes of Relativity and Quantum Mechanics, I acknowledge that they work, but reject the various interpretations offered as to their reliability as an explanation of the nature of things like space, time, light, and gravity. And since I don’t follow anyone’s parade, it makes no difference to me what the religion, ethnicity, etc. of the one making the interpretations.

Contrary to your rash judgment (to which you are so often prone ) I did not cite him as an authority figure but as a qualified kindred spirit . And speaking of authority figures, you yourself often make use of them. So, good for the goose but not the gander?

The lesson might be that when advocating for your opinion, do enough research up front to make sure your chosen authorities/spirits are credible or it will rebound on you.

But advocacy isn’t appropriate to some subjects. In science the final arbiter is always the empirical evidence. If a theory doesn’t agree with experiment, it goes in the trash, no matter whether Einstein or the Queen of Sheba herself said it.

You are free to believe in the Queen’s theory if you wish, you can shout it from the rooftops, you can advocate it and get the whole world on her side, but it still won’t be true. If people want to believe things which have be ruled out by evidence, even after that’s been explained to them, then let them, in science they are free to believe whatever they want, because what they believe can’t change the truth of the evidence.

So when we refer to Einstein or Newton, it should just be taken as referring back to a source, never that it must be believed because a famous guy said it.

 

[inocente]

And since I don’t understand the physics and math of the various modes of Relativity and Quantum Mechanics, I acknowledge that they work, but reject the various interpretations offered as to their reliability as an explanation of the nature of things like space, time, light, and gravity.

On that point, it’s important to separate what a theory says from how it could be interpreted. If a theory agrees with experiment, you can’t cherry pick unless you can show that the parts of the theory you like would still agree with experiment when the parts you don’t like are removed.

On the other hand, an interpretation is an opinion on what a theory might mean, and that’s outside the science, it’s metaphysics. For example, there are dozens of interpretations on what quantum mechanics might mean. None of them cherry pick, they all start by accepting the whole theory, and then philosophize about what that might mean.

 

[inocente]

This does not make sense to me, in my opinion.

What does it sound like to you? (If you would like to give your ideas, thanks)

At one extreme there are those who think that we can know everything by sitting in a windowless room and thinking really hard. They think that math and the laws preexist (otherwise they couldn’t know them just by thinking really hard). These guys are “extreme rationalists”.

At the other extreme are those who say we can only know anything by getting out of the room and experiencing the world. They think that math and the laws are just ways of describing what we experience. These guys are “extreme empiricists”.

Your question is very deep though, have a look at the Allegory of the Cave for Plato’s opinion.

 

[Linusthe2nd]

The lesson might be that when advocating for your opinion, do enough research up front to make sure your chosen authorities/spirits are credible or it will rebound on you.

One could make the same observations about those " authorities/spirits " who suggest the universe created itself or that there are multiverses. By your view these would have to be excluded from the conversation.

But advocacy isn’t appropriate to some subjects. In science the final arbiter is always the empirical evidence. If a theory doesn’t agree with experiment, it goes in the trash, no matter whether Einstein or the Queen of Sheba herself said it.

I can consturct a four dimensional graph with the aid of mathematics, that does not mean the universe is actually four dimensional, even if Einstein’s camp followers or the Queen of Sheba, shout it " from the rooftops. "

You are free to believe in the Queen’s theory if you wish, you can shout it from the rooftops, you can advocate it and get the whole world on her side, but it still won’t be true. If people want to believe things which have be ruled out by evidence, even after that’s been explained to them, then let them, in science they are free to believe whatever they want, because what they believe can’t change the truth of the evidence.

The point is that the evidence does not speak to the nature of things, it speaks to a model that gives the " correct " answer. " Correct " in the provisional sense used by science. But nature is not provisional and that is the point, nature is the same as it was since the beginningt of time ( if one believes in such a beginning ) or eternally so ( if one does not believe in a beginning. ).

So when we refer to Einstein or Newton, it should just be taken as referring back to a source, never that it must be believed because a famous guy said it.

Well, my guy certainly wasn’t famous . But I agree. Of course, most of us ordinary folk are in the position that we cannot, on our own, know whether such men or their camp followers are correct or not. But if we unerstand Aristotle’s concept of nature, we can judge the validity of what modern cosomologists say what these theories mean. And when what they say violates the nature of things, then we can reject their interpretations as contrary to reason .

Well, the tone was more moderate than usual. Congratulations.

Linus2nd

 

[Jim_Baur]

richca innocente bahman et al

THANKS!

 

[inocente]

Well, the tone was more moderate than usual. Congratulations.

Why the condescension? I wasn’t trying to win an argument, only to explain a point of view.

If I understand, you’re saying that Aristotle’s physics is closer than modern physics to your intuitions about the world and so is more satisfying to you.

But Aristotle argues that intuitions and emotions are governed by the appetitive soul, and that it must be trained by the rational soul to be in harmony with the ways of wisdom. (Incidentally, I think he says his analysis is provisional, just like science still is ).

We learn that our intuitions are often wrong, and we must get past them to see the world as it really is. So sure, modern physics will test your intuitions, and if you don’t want that then stay away from it.

Now brighten up bro, lets turn that frown upside down!

 

[Linusthe2nd]

Why the condescension? I wasn’t trying to win an argument, only to explain a point of view.

If I understand, you’re saying that Aristotle’s physics is closer than modern physics to your intuitions about the world and so is more satisfying to you.

But Aristotle argues that intuitions and emotions are governed by the appetitive soul, and that it must be trained by the rational soul to be in harmony with the ways of wisdom. (Incidentally, I think he says his analysis is provisional, just like science still is ).

We learn that our intuitions are often wrong, and we must get past them to see the world as it really is. So sure, modern physics will test your intuitions, and if you don’t want that then stay away from it.

Now brighten up bro, lets turn that frown upside down!

But the nature of things is not an " intuition, " even to Aristotle .

Fun as always.

Linus2nd

 

[inocente]

But the nature of things is not an " intuition, " even to Aristotle .

I don’t think you could argue that his ideas became so widely accepted, in the absence of any testing, because they are counter-intuitive. His notions such as heavier weights fall faster are intuitive, but wrong when tested.

Fun as always.

Psalm 133

 

[Jim_Baur]

Humanity and Christianity and Judaism could all use a lot more of Ps. 133.

 

[Linusthe2nd]

I don’t think you could argue that his ideas became so widely accepted, in the absence of any testing, because they are counter-intuitive. His notions such as heavier weights fall faster are intuitive, but wrong when tested.

That is not the point at all, the point is that he was the first ( as far as I know ) who explained that all substances have a nature from which flow all their physical attributes, behaviors, and powers, etc. It as self evident truth upon which all science depends. Wasn’t aware that he thought disparate weights fell at the different speeds. I’ve read Physics but can’t remember everything, and some of it is pretty obtuse, I’ll take your word for it…

Psalm 133

" Behold, bless the Lord, all ye servants of the Lord
who stand in the house of the Lord during the hours
of the night…? " The numbering varies.

Linus2nd

 

[inocente]

That is not the point at all, the point is that he was the first ( as far as I know ) who explained that all substances have a nature from which flow all their physical attributes, behaviors, and powers, etc. It as self evident truth upon which all science depends.

I don’t believe that’s the case in modern science. The notion of natures, although intuitive, turns out to be false. The properties of carbon (or any other element) don’t exist in the particles from which it is made. The properties of a cell don’t exist in the chemicals from which it is made. The properties of an elephant don’t exist in the cells from which it is made.

Even the notion of substance comes into question as virtually all of an atom is space.

" Behold, bless the Lord, all ye servants of the Lord
who stand in the house of the Lord during the hours
of the night…? " The numbering varies.

You are a stickler for tradition. Here’s the RSV (Catholic Edition)

 

[Bahman]

I don’t believe that’s the case in modern science. The notion of natures, although intuitive, turns out to be false. The properties of carbon (or any other element) don’t exist in the particles from which it is made. The properties of a cell don’t exist in the chemicals from which it is made. The properties of an elephant don’t exist in the cells from which it is made.

Even the notion of substance comes into question as virtually all of an atom is space.

That is the meaning of complexity. A combination being is more than simple sum of beings.

 

[Linusthe2nd]

I don’t believe that’s the case in modern science. The notion of natures, although intuitive, turns out to be false. The properties of carbon (or any other element) don’t exist in the particles from which it is made. The properties of a cell don’t exist in the chemicals from which it is made. The properties of an elephant don’t exist in the cells from which it is made.

I think you have the wrong idea of a nature or essence ( or substance ). The nature or essence cannot be seen. What is seen is material structure ( external and interior ), behavior, powers, etc. The nature of an elephant is known by the latter notes from which they flow, it is their sourse. The nature is inerior to everything else. The behavior and powers of a substance are not and cannot be determined by the interior cells, atoms, etc. because they are clearly organized for a different purpose in every substance in which they exist. In some substances they give rise to horses, in others cows, in others trees, etc. So there must be an organizing factor, a controlling factor which directs the same cells, atoms, etc to form a different type of substance. This controlling factor Aristotle calls a nature/essence/substance. " Horseness " is the nature or controlling factor of a horse. Human nature is the controlling factor of man.

All sciences assume the existence of these controlling factors which account for the distinction between the substances which exist in their system of categorizing. They do not often refer to the nature of these substances - atoms, animals, vegatables, etc… they just take them for granted. Science would be impossible if they did not exist.

Even the notion of substance comes into question as virtually all of an atom is space.

Aristotle defined a substance as that which did not exist in another - essentially. We may have two substances in a compoud, but the compound would not be a substance in the proper sense. Even if most of an atom is " empty " space ( " empty " because we don’t actually know this is so ), the atom still has a recognizable nature or essence or substance. Each atom on the periodic table is different from every other.

• I have used nature, essence, substance as synonomous terms because Aristotle often used them that way. But in this discussion nature is emphasized as being in most common useage in non-philosophical, non-theological circles.

You are a stickler for tradition. Here’s the RSV (Catholic Edition)

It is # 132 in my My Daily Psalm Book.U].

Linus2nd

 

[bmonk]

Thanks, that guy [Dr. T. Van Flandern] is hilariously kooky. Apparently he became disenchanted at the lack of interest in his notion of exploding planets. He reckoned humans come from Mars, which used to be a moon of an exploded planet. That comets and asteroids come from another exploded planet. That various bits of landscape on Mars were carved by extra-terrestrials from another exploded planet.

I love it. Where’s his evidence? Oh sorry, it exploded, all gone. Just take his word for it.

Another of his many kooky ideas was that gravity comes from “a flux of invisible ultra-mundane corpuscles”. Limitless energy! Perpetual motion!

(sources for above: the website you linked and Wikipedia)

I still can’t decide whether it’s all a prank for comedic value, or whether he was serious. Anyway, RIP oh strange doctor.

I’m assuming you weren’t taken in. You weren’t were you?

PS: I didn’t think there was anything left to say on your other points so shout if I didn’t answer anything.

As Wolfgang Pauli used to say, “That idea is not even wrong!” That it, it makes no predictions and has no evidence by which it can be shown to be false–and so it is not science.

 

[bmonk]

Nope, photons are mass-less. Been proven down to itsy bitsy levels. See here.

Are they speaking of the “rest mass” of the photon? According to Relativity, if a photon has energy (as it does, related to its wavelength), then that energy is equivalent to a mass, albeit very small. So any actual photon does have energy, and also mass.

 

[Linusthe2nd]

Are they speaking of the “rest mass” of the photon? According to Relativity, if a photon has energy (as it does, related to its wavelength), then that energy is equivalent to a mass, albeit very small. So any actual photon does have energy, and also mass.

That is what I have been insisting all along. And it is that mass that allows the bending of light. It is therefore not true to say that space curves and/or that time curves. These are mathematical conveniences only, they do not represent the true nature of things ( i.e. light, space, time, gravity ).

P.S. I do not believe in U.F.Os, little green men, or multiverses. It has always seemed odd to me that those who insist on multiverses, should view my own convictions as odd .
As Peter Whimsy might say, " very odd indeed. "

Linus2nd

 

[Richca]

I don’t believe that’s the case in modern science. The notion of natures, although intuitive, turns out to be false. The properties of carbon (or any other element) don’t exist in the particles from which it is made. The properties of a cell don’t exist in the chemicals from which it is made. The properties of an elephant don’t exist in the cells from which it is made.

Even the notion of substance comes into question as virtually all of an atom is space.

You are a stickler for tradition. Here’s the RSV (Catholic Edition)

The notion of natures as understood by Aristotle is just as valid today as it was in Aristotle’s day. Nobody denies that things have natures such as human beings, lions, tigers, oak trees, or elements. Although Aristotle thought that natures apply more to living things, it can be used in a wide sense to apply to inanimate things. The nature of something is simply the essence of something which is equivalent to the definition of a thing.
Aristotle held that material substances are composed of two essential principles, i.e., form and matter. It is the form of things that determines the nature or essence of things while the matter is what individuates things. For example, the element of carbon would have the form of carbon while its matter is composed of a certain number of protons, nuetrons, and electrons. The union of form and matter is what makes up a substance. Carbon has other qualities or properties as well which are derived from the form or matter of carbon and which are called accidents such as what science calls electrical charges or electromagnatism, strong and weak forces, and gravity. Protons, neutrons, and electrons are not the substance of carbon per se, but its proper quantitative accident for quantity, which is the first accident of a material substance, extends matter into parts and three dimensional space.

 

[Linusthe2nd]

The notion of natures as understood by Aristotle is just as valid today as it was in Aristotle’s day. Nobody denies that things have natures such as human beings, lions, tigers, oak trees, or elements. Although Aristotle thought that natures apply more to living things, it can be used in a wide sense to apply to inanimate things. The nature of something is simply the essence of something which is equivalent to the definition of a thing.
Aristotle held that material substances are composed of two essential principles, i.e., form and matter. It is the form of things that determines the nature or essence of things while the matter is what individuates things. For example, the element of carbon would have the form of carbon while its matter is composed of a certain number of protons, nuetrons, and electrons. The union of form and matter is what makes up a substance. Carbon has other qualities or properties as well which are derived from the form or matter of carbon and which are called accidents such as what science calls electrical charges or electromagnatism, strong and weak forces, and gravity. Protons, neutrons, and electrons are not the substance of carbon per se, but its proper quantitative accident for quantity, which is the first accident of a material substance, extends matter into parts and three dimensional space.

Very well said.

Linus2nd

 

[hecd2]

That is what I have been insisting all along. And it is that mass that allows the bending of light. It is therefore not true to say that space curves and/or that time curves. These are mathematical conveniences only, they do not represent the true nature of things ( i.e. light, space, time, gravity ).

I don’t think this is right. The invariant mass which is used in calculating the dynamics of moving objects is the rest mass of the body not its relativistic mass. This is necessarily so, otherwise the calculation would give different results in different frames of reference - in other words you would calculate different trajectories depending on which frame of reference you are working in. But the body has only one trajectory and you have to be able to calculate it correctly independent of frame of reference. (The general Special Realtivity formula relating the energy of particle moving with respect to particular frame is E^2=m^2c^4 + p^2c^2 where p is its momentum - if the velocity of the particle is zero then this reduces to E=mc^2; in the case of light m=0 so E=pc where p is the momentum of the photon - p=hc/lambda where h is Planck’s constant and lambda its wavelength.)

So the mass of a body in a classical dynamical calculation is its rest mass and the rest mass of the photon is zero. The fact that the path of a photon is deflected by a gravitational field can be predicted even in Newtonian mechanics and even with a rest mass of zero - the acceleration of a particle caused by the gravitational field of a body depends only on the mass of the attracting body and the location of the particle with respect to it (a=GM/r^2) - it does not depend on the mass of the particle. In other words all particles experience the same acceleration in the gravitational field of a massive body, independent of their own mass (this principle refutes the erroneous Aristotlean notion that the rate of fall of bodies depends on their mass).

But here’s the kicker. Classical mechanics and Special Relativity predict a certain deflection of light by gravity. General Relativity, which starts with the concept that space is not necesssarily Euclidean and can be curved by gravity, predicts that light will be deflected by twice as much by treating light as travelling on geodesics (locally straight lines) in curved spacetime. And experiment shows that the General Relativity prediction is the correct one.

It seems to me odd that Linus can say, quite seriously, “I think I’ll stick with Newton” (versus Einstein’s GR), because this is saying, in effect: “I reject a physical theory (GR) which predicts everything that we can currently observe about gravity and the nature of spacetime in favour of one (Newtonian mechanics) which demonstrably fails to predict some observations correctly and which is therefore a less accurate description of reality”. That seems to me to be profoundly irrational.

 

[Linusthe2nd]

Hecd2 has rejected my explanation of the bending of light near a gravitational mass saying, " It seems to me odd that Linus can say, quite seriously, ’ I think I’ll stick with Newton’ (versus Einstein’s GR), because this is saying, in effect: ’ I reject a physical theory (GR) which predicts everything that we can currently observe about gravity and the nature of spacetime in favour of one (Newtonian mechanics) which demonstrably fails to predict some observations correctly and which is therefore a less accurate description of reality ’ . That seems to me to be profoundly irrational. "

First, to say, " I reject a physical theory (GR) which predicts everything that we can currently observe about gravity and the nature of spacetime in favour of one (Newtonian mechanics) which demonstrably fails to predict some observations correctly and which is therefore a less accurate description of reality " is not my position at all. As regards the theory of ( GR ) I make no more judgment than scientists make, it seems to work. So I do not reject the theory, I reject its interpretation - that space and time curve and that photons have no mass…

Hecd2 has made a is a value judgment without merit. Are we to think then that the " bending of space, the bending of time " are applicable only to light? If so that would leave us in a very confused universe. One in which space and time curve for light but not for all the other objects in space. But if it applies to all objects in space, then it would seem that every solar system would have its own pecular system of curved space and time. Would this mean that all curved space-time is purely local? As Lord Whimsy might say, " Very odd indeed. " And wouldn’t there be, somewhere in the universe, conflicting paths of this curved space-time, as between solar systems or between galaxies?

Under Hecd2’s explanation, we would have to discard the notion that gravitational bodies, such as any object larger than a photon, are governed not by the attraction and repelling of gravitaty but by the bending of space-time!!

It is more consistent with the nature of things to recognize that we can have a mathematical formula which gives the correct outcome but does not reflect the nature of things. .

So it is more logical to say that nature always remains the same, irregardless of a particular mathematical formula, that space does not bend and that time does not bend and that photons have mass like every other body in space, and that the mass of photons is overcome by the gravitational mass of other greater gravitational masses?.

Furthermore, are space and time real substances like a stick or a fishing rod that can bend? I don’t see how they can be regarded as actually existing things. Show me an object you call space, another that you call time. Put them under a microscope, or show them to me on an oscilloscope.

And did Einstein actually say that space curves and that time curves? If it wasn’t him, who first made that philosophical interpretation?

Linus2nd