Extraordinary claims require extraordinary proof

[robinson]

The photon will not "change because of gravity". As far as it is concerned it is moving along a straight line with no forces acting on it (see Newton's First Law). But space-time is warped by gravity so that line is actually bent. Thus the direction of travel of the photon is bent.

Exactly. Photons are not effected by gravity, just as they don't effect gravity. The path of photons can be deflected by warped spacetime, due to very strong gravity, but to the photon nothing has changed, it just takes a straight path through.

Black holes warp spacetime so much photons essentially follow spacetime and never are seen, but they don't lose or gain energy. Or change frequency, or change in any way.

Maybe. This is mostly theory, because nobody really knows. Just like we don't know how gravity works. Yet.

Gravitational lensing is just light following warped spacetime, the photons are not effected by gravity. Which is why sol is just being silly. Photons don't change a bit, no matter how much gravity there is. Which is weird. As weird as gravity not being effected by anything else.

Maybe. This stuff about magnetism changing gravity is dang interesting.

 

[ynot]

You are right - a 2D balloon has only a surface. If that seems incredible to you then what about the mobius strip - it is a surface with inly 1 side!

Converting reality to abstract math means that we can predict things.

Are you saying that a mobius band (it’s not a strip) proves (or supports in any way) that a 2D balloon can have actual existence? I hope not.

I have no problem with math being used to making abstract predictions.

 

[robinson]

Math can also be used to make real predictions. We do this all the time. At the Quantum level, it used to be agreed that while the models and math didn't actually describe what was really happening, because it worked well enough to predict stuff, we would all agree to go along with it, even though it couldn't possibly be what was really happening.

 

[Reality Check]

Exactly. Photons are not effected by gravity, just as they don't effect gravity. The path of photons can be deflected by warped spacetime, due to very strong gravity, but to the photon nothing has changed, it just takes a straight path through.

Black holes warp spacetime so much photons essentially follow spacetime and never are seen, but they don't lose or gain energy. Or change frequency, or change in any way.

Maybe. This is mostly theory, because nobody really knows. Just like we don't know how gravity works. Yet.

Gravitational lensing is just light following warped spacetime, the photons are not effected by gravity. Which is why sol is just being silly. Photons don't change a bit, no matter how much gravity there is. Which is weird. As weird as gravity not being effected by anything else.

Maybe. This stuff about magnetism changing gravity is dang interesting.

You needed to insert "directly" into your sentences, e.g "Photons are not directly effected by gravity".
Photons have energy. Energy is mass. Mass causes gravity. Therefore photons affect gravity.
The reverse is true: Gravity affects mass. Mass is energy. Photons have energy. Therfore gravity affects photons.

"mostly theory" and a lot of observations, e.g. a dozen black hole candidates in our galaxy, the observed supermassive black hole at the center of our galaxy and the even bigger one in M87, etc.

What do you mean by "we don't know how gravity works. Yet"? Do you have a refutation of General Relativity? You state how gravity works yourself - mass bends space-time.

 

[ynot]

Math can also be used to make real predictions. We do this all the time. At the Quantum level, it used to be agreed that while the models and math didn't actually describe what was really happening, because it worked well enough to predict stuff, we would all agree to go along with it, even though it couldn't possibly be what was really happening.

Sorry - the word abstract was meant to go before the word math, not predictions.

 

[ynot]

At the Quantum level, it used to be agreed that while the models and math didn't actually describe what was really happening, because it worked well enough to predict stuff, we would all agree to go along with it, even though it couldn't possibly be what was really happening.

This sound uncomfortably similar to believers justifying their beliefs by saying “it seems to work”.

 

[Reality Check]

This sound uncomfortably similar to believers justifying their beliefs by saying “it seems to work”.

QM does not "seem to work" - it produces predictions that match experiments and so actually works. If you doubt that QM works then just look at your PC which depends on semiconductors, i.e. quantum effects.

It is not a belief - it is a theory backed up by a massive body of evidence.

 

[sol invictus]

Exactly. Photons are not effected by gravity, just as they don't effect gravity. The path of photons can be deflected by warped spacetime, due to very strong gravity, but to the photon nothing has changed, it just takes a straight path through.

OK robinson. Whatever you say.

 

[Klimax]

Robinson,I will go out of my way to tell you,that you should not visit this subforum anymore.Your knowledge is flawed and/or warped beyond all limits.

You are no longer sceptic,but a fool of BAC-Zeuss magnitude.

Gravity affects light.That is why for example gravity is "ruling" on tha large scale.That is why we cannot see black holes.That is why there is nice effect during sun eclipse caused by planet/moon.

When something predicts stuff,which has been confirmed,then the theory is corret and model is good.And since we observed predicted things,underlying math thus describes reality...

ETA:
Path of light is curved due to gravity all the time.And that is in fact DIRECT effect.

 

[Dancing David]

This sound uncomfortably similar to believers justifying their beliefs by saying “it seems to work”.

Not really, it does more than seem to work, it makes accurate predictions of th ebehavior of objects.

Do you really understand what science is?

In brief human thoughts are maps of the behavior of reality. We make theories that try to model the behavior of the reality. The ability to predict the behavior or describe the behavior of reality with precision is what makes a thoey valid.


Now what you said was a real muddle of maps:

Wishful thinking, confimation bias and selective sample are equatable to huge sample, mathematical rigour (like chemistry is explained by QM) and huge amounts of accurate predictions.

 

[sol invictus]

The photon will not "change because of gravity". As far as it is concerned it is moving along a straight line with no forces acting on it (see Newton's First Law). But space-time is warped by gravity so that line is actually bent. Thus the direction of travel of the photon is bent.

To add to this: the fundamental insight of general relativity is that gravity can be thought of not as a force, but rather as a warping of spacetime. In this way of thinking of things all particles propagate along "straight lines" - or rather their curved space analogs, which are called geodesics - unless acted on by a (non-gravitational) force. If you're observing a body moving in such a warped spacetime and aren't aware of the curvature, its path looks curved - much as the path a jet takes across the Atlantic looks curved when drawn on a flat map.

Everything I've just said holds for all particles and free bodies, from photons to cosmic rays to the earth. The only difference is that massless particles follow a special kind of geodesic called null, which the same as the geodesic a massive body would follow after you accelerated it for a very long time (so that it was moving very close to the speed of light).

If you launch a projectile from a gravitational well, for example up from the surface of the earth, its kinetic energy will decrease as it ascends. It will escape if its initial velocity was high enough, otherwise it will reach a highest point and fall back to the surface.

If you shoot a laser beam up from the surface of the earth, the wavelength of the light will increase and the beam will lose energy in essentially the same way and for the same reason. It will escape from the earth because its initial velocity is very high, but would not if the gravity well were deep enough (i.e. a black hole).

Gravity acts on photons in just the same way it acts on you. The only difference is that photons move really fast, but they are still significantly deflected by gravity, as is seen every day by astronomers looking for gravitational lensing.

 

[robinson]

This sound uncomfortably similar to believers justifying their beliefs by saying “it seems to work”.

Well, then I did a bad job of describing it, or you didn't understand what I meant. While it may be extreme topic drift, it would be worthwhile to explain, so you don't get the wrong idea.

QM does not "seem to work" ..

Considering the word "work", that might be the stumbling block. Work, in physics, has a different meaning than all the other meanings we associate with "work". To say something works, in regards to science, can be confusing.

How about this. The theories involving Quantum Mechanics, are useful to predict events that occur in realms the human senses can not detect. They are the best theories based on the evidence. The evidence is based on perception of what occurs.

Since we can't actually detect or see sub-atomic particles or events, we have theories about them, and because they actually describe and predict behaviors, we agree that they are wise and good, even if we are not sure about what is really going on.

For example, we can't observe a black hole, too much light and energy around it, so we theorize what is going on. We can never know what is really going on, but we might agree that a theory describes what we can observe, so at that point we say the theory "works". But nobody would mistake the theory for the actual event.

The interior of the sun may be another case. We will never actually know what is occurring, but theories allow us to imagine we do.

It is not a belief - it is a theory backed up by a massive body of evidence.

A theory, not a belief. This is a common sticking point in discussing science. Somebody came up with a thread about having a new word. I'm starting to understand why.

 

[robinson]

Bottom line, a good theory allows accurate predictions about future events. Belief will not change what occurs, but a good theory allows one to change the future, and know with certainty what will be the result of such actions.

OK maybe that wasn't the bottom line. But belief only plays a small part in a theory.

 

[Reality Check]

Well, then I did a bad job of describing it, or you didn't understand what I meant. While it may be extreme topic drift, it would be worthwhile to explain, so you don't get the wrong idea.

Considering the word "work", that might be the stumbling block. Work, in physics, has a different meaning than all the other meanings we associate with "work". To say something works, in regards to science, can be confusing.

How about this. The theories involving Quantum Mechanics, are useful to predict events that occur in realms the human senses can not detect. They are the best theories based on the evidence. The evidence is based on perception of what occurs.

Since we can't actually detect or see sub-atomic particles or events, we have theories about them, and because they actually describe and predict behaviors, we agree that they are wise and good, even if we are not sure about what is really going on.

For example, we can't observe a black hole, too much light and energy around it, so we theorize what is going on. We can never know what is really going on, but we might agree that a theory describes what we can observe, so at that point we say the theory "works". But nobody would mistake the theory for the actual event.

The interior of the sun may be another case. We will never actually know what is occurring, but theories allow us to imagine we do.

A theory, not a belief. This is a common sticking point in discussing science. Somebody came up with a thread about having a new word. I'm starting to understand why.

Once again you are missing the "directly" word.
QM applies to small scales not just sub-atomic particles. Electrons are not sub-atomic particles. The bucky-balls (carbon 60) used to test the limits of QM in two-slit experiments are not sub-atomic particles.

 

[MattusMaximus]

Sure. The neutron/proton mass splitting is in part due to the difference in charge (i.e. the energy in the EM field of the proton). That difference is overwhelmed by other factors (which is why the proton is lighter), but nevertheless it contributes to measurable mass differences in elements. There are other examples like that in particle physics - charged versus neutral pion mass splitting, kaons etc. - but it's a little harder to weigh those particles gravitationally.

Theoretically speaking, gravity acts on all forms of energy including EM. For example you could make a black hole out of photons, or out of a big region containing an electric or magnetic field.

Thanks for the clarification Sol - I feel like a dope for missing this. That's what I get for posting on the run.

I suppose what I was thinking of when I critiqued robinson's question was the forces of interactions themselves and how they tie together in a hypothetical unified theory of physics.

Of course, it doesn't seem that robinson is capable of understanding what he's even asking, so I guess I cannot blame myself too much for not knowing either

 

[MattusMaximus]

Gravity acts on photons in just the same way it acts on you. The only difference is that photons move really fast, but they are still significantly deflected by gravity, as is seen every day by astronomers looking for gravitational lensing.

To add one point of clarification for others, photons will still travel at the speed of light even if they're climbing out of a gravity well (recall that in relativity theory the speed of light is invariant). The energy loss of the photon (analogous to a massive object slowing down and losing kinetic energy) as it climbs up the well comes in with the shift in photon wavelength that Sol mentioned. This effect is called gravitational redshift and has been observed innumerable times.

 

[MattusMaximus]

Since we can't actually detect or see sub-atomic particles or events, we have theories about them, and because they actually describe and predict behaviors, we agree that they are wise and good, even if we are not sure about what is really going on.

Robinson must be high... we observe and detect sub-atomic particles all the time. I just had some of my students detect electrons via the Millikan Oil Drop experiment a few weeks ago.

And later this year, my AP students will perform an experiment where they detect muons as a test of relativistic time dilation.

Not to mention, I think I can safely say that I'm one of the few people on the JREF Forum who has actually seen individual atoms. I did this in graduate school using a device called an atomic force microscope.

But none of those things are "real" according to robinson - he says all we have is "just theories". Good grief

For example, we can't observe a black hole, too much light and energy around it, so we theorize what is going on. We can never know what is really going on, but we might agree that a theory describes what we can observe, so at that point we say the theory "works". But nobody would mistake the theory for the actual event.

Yup, and the wind isn't real either because robinson can't see it with his eyes. That goes the same for infrared & ultraviolet radiation, X-rays, etc.

The interior of the sun may be another case. We will never actually know what is occurring, but theories allow us to imagine we do.

More of robinson's nonsense. Try reading up on this...

http://en.wikipedia.org/wiki/Sun#Structure

"The solar interior is not directly observable, and the Sun itself is opaque to electromagnetic radiation. However, just as seismology uses waves generated by earthquakes to reveal the interior structure of the Earth, the discipline of helioseismology makes use of pressure waves (infrasound) traversing the Sun's interior to measure and visualize the Sun's inner structure. Computer modeling of the Sun is also used as a theoretical tool to investigate its deeper layers."

A theory, not a belief. This is a common sticking point in discussing science. Somebody came up with a thread about having a new word. I'm starting to understand why.

No matter what you call it, robinson is quickly displaying that he'd screw it up regardless

 

[MattusMaximus]

Exactly. Photons are not effected by gravity, just as they don't effect gravity. The path of photons can be deflected by warped spacetime, due to very strong gravity, but to the photon nothing has changed, it just takes a straight path through.

Black holes warp spacetime so much photons essentially follow spacetime and never are seen, but they don't lose or gain energy. Or change frequency, or change in any way.

Maybe. This is mostly theory, because nobody really knows. Just like we don't know how gravity works. Yet.

Gravitational lensing is just light following warped spacetime, the photons are not effected by gravity. Which is why sol is just being silly. Photons don't change a bit, no matter how much gravity there is. Which is weird. As weird as gravity not being effected by anything else.

Maybe. This stuff about magnetism changing gravity is dang interesting.

Robinson really needs to take this advice...

 

[robinson]

Today, 05:13 PM

MattusMaximus
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Today, 05:18 PM

MattusMaximus
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Today, 05:29 PM

MattusMaximus
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Today, 05:32 PM

MattusMaximus
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4 posts in 19 minutes. I think I'll keep on ignoring the troll.

 

[robinson]

Once again you are missing the "directly" word.

Where would you add the word?