Jump to content

Interference vs. Lensing


Recommended Posts

3 minutes ago, swansont said:

You did, in the first sentence of the OP.

Yes, but only to in mentioning it as not being a factor in the explanation. Really, I do believe in gravitational lensing, but I do not believe that it is the whole story. I'm not presenting a new idea, I'm only applying an old one in a new way. Really I should be defending Young's Double slit, wave theory, and string theory, because that is what's being dismissed by SF members.

34 minutes ago, beecee said:

Your table is solid from your scale of perspective. But if you could shrink yourself down to the size of a  proton, you would witness the electron repulsion that actually stops your hand falling through the table. They are both real situations and not unsupported crap that you do seem to make up quite often.

Science does not actually seek reality: It constructs models that describe and match the observational and experimental data that we have. If it happens to hit on this "reality"all well and good. Here is a short video: I hope you take the time to watch it and understand what I mean...... https://www.youtube.com/watch?v=MO0r930Sn_8

So what your saying is that they are both true... like 2+2=4 but 2x2=4 as well? I wonder who mentioned that earlier...? I hope you understand what I mean.

Link to comment
Share on other sites

15 minutes ago, AbnormallyHonest said:

Yes, but only to in mentioning it as not being a factor in the explanation. Really, I do believe in gravitational lensing, but I do not believe that it is the whole story. I'm not presenting a new idea, I'm only applying an old one in a new way. Really I should be defending Young's Double slit, wave theory, and string theory, because that is what's being dismissed by SF members.

:) You don't believe it is the whole story? Well once again, at the risk of sounding like a broken record, give us some evidence that leads you to this "belief" and your many other "beliefs"while at the same time, seemingly ignoring all the evidence for current incumbent theories like the BB and GR. You know the score, re any Tom, Dick and Harry. 

Quote

So what your saying is that they are both true... like 2+2=4 but 2x2=4 as well? I wonder who mentioned that earlier...? I hope you understand what I mean.

Yes both true and relative to the scale of perspective. But I certainly do not see that in anyway invalidating gravitational lensing.But did you watch the video...only 7 minutes long.

Link to comment
Share on other sites

24 minutes ago, beecee said:

:) You don't believe it is the whole story? Well once again, at the risk of sounding like a broken record, give us some evidence that leads you to this "belief" and your many other "beliefs"while at the same time, seemingly ignoring all the evidence for current incumbent theories like the BB and GR. You know the score, re any Tom, Dick and Harry. 

Yes both true and relative to the scale of perspective. But I certainly do not see that in anyway invalidating gravitational lensing.But did you watch the video...only 7 minutes long.

Excuse me if you please... yet you have empirical evidence of dark matter, or is just a dark area of understanding due to the disparity between the concepts we believe and observation. Rather than inventing something just to validate a concept that doesn't work, why not apply real science, such as Young's Double Slit, which is a reality, and should be applied to other situations. I'm not invalidating it, observation does, unless, of course, applying some real science to the dark areas of understanding might shed some light on the dark areas of science.

P.S. Yes I enjoyed the video very much, but what do you care what other people think?

Edited by AbnormallyHonest
Link to comment
Share on other sites

57 minutes ago, AbnormallyHonest said:

Yes, but only to in mentioning it as not being a factor in the explanation. Really, I do believe in gravitational lensing, but I do not believe that it is the whole story. I'm not presenting a new idea, I'm only applying an old one in a new way. Really I should be defending Young's Double slit, wave theory, and string theory, because that is what's being dismissed by SF members.

No it's not. If you did a double-slit experiment with white light, you would get colored fringes, because the interference is wavelength-dependent. IOW, not what we see. We can rule it out.

There's also the matter of scale. Two reasons I asked for you to present some calculations.

 

Link to comment
Share on other sites

24 minutes ago, swansont said:

No it's not. If you did a double-slit experiment with white light, you would get colored fringes, because the interference is wavelength-dependent. IOW, not what we see. We can rule it out.

There's also the matter of scale. Two reasons I asked for you to present some calculations.

 

If you get colored fringes, isn''t that different than what you would see in diffraction? I'm pretty sure a diffraction crystal projects a rainbow pretty uniformaly, it isn't just the fringes... so we can rule it out.

The double slit experiment produces an interference pattern... it has interference, it interferes with itself, and yes interference behaves differently depending on differing wavelengths. At the fringes, the probability changes, as does the probability of both constructive and destructive interference dependent on the wavelength of light. Amplifying some and destroying others with discretion because it is, as you say, on the fringes of a non-discrete distribution of probability.

Yes there is a matter of scale, but wouldn't anything presented on scales of that magnitude really just speculation... I mean, unless we've been there to observe, or at least from a displacement of equal magnitude.

Edited by AbnormallyHonest
Link to comment
Share on other sites

1 hour ago, AbnormallyHonest said:

If you get colored fringes, isn''t that different than what you would see in diffraction? I'm pretty sure a diffraction crystal projects a rainbow pretty uniformaly, it isn't just the fringes... so we can rule it out.

No, colored fringes are exactly what you would see in diffraction if you used a wide spectrum source. But people don't generally do this. They use monochromatic light.

spalt1.png

1 hour ago, AbnormallyHonest said:

The double slit experiment produces an interference pattern... it has interference, it interferes with itself, and yes interference behaves differently depending on differing wavelengths. At the fringes, the probability changes, as does the probability of both constructive and destructive interference dependent on the wavelength of light. Amplifying some and destroying others with discretion because it is, as you say, on the fringes of a non-discrete distribution of probability.

And do we observe this?

1 hour ago, AbnormallyHonest said:

Yes there is a matter of scale, but wouldn't anything presented on scales of that magnitude really just speculation... I mean, unless we've been there to observe, or at least from a displacement of equal magnitude.

No, it's physics.

Link to comment
Share on other sites

8 hours ago, AbnormallyHonest said:

Well, I would agree with you, but the diffraction patters are due to the different wavelengths of light, which all enter a changing medium differently causing disparity in the angles of diffraction for varying colors. This isn't the case with gravitational lensing, because there is no change in medium and therefore none in velocity. If you check out TUB's post there's a link to Fermat's Principle which helps explain this.

You would agree with me if you knew what you were talking about; specifically if you understood the difference between refraction and diffraction.

Both generally cause dispersion.

Only one of then needs more than 1 medium through which the light is transmitted 

No pretty colours means no refraction or diffraction.

 

But gravitational lensing is independent of wavelength.

\theta ={\frac  {4GM}{rc^{2}}}

from 

https://en.wikipedia.org/wiki/Gravitational_lens

8 hours ago, AbnormallyHonest said:

I'm only applying an old one in a new way. Really I should be defending Young's Double slit,

Well, the double slit image using white light looks like this

https://en.wikipedia.org/wiki/Double-slit_experiment#/media/File:Double_slit_interference.png

lots of pretty colours.

So, we know that the image attributed to gravitational lensing can't be due to anything like the double slit experiment.

You can stop now.

Link to comment
Share on other sites

9 hours ago, AbnormallyHonest said:

Excuse me if you please... yet you have empirical evidence of dark matter, or is just a dark area of understanding due to the disparity between the concepts we believe and observation. Rather than inventing something just to validate a concept that doesn't work, why not apply real science, such as Young's Double Slit, which is a reality, and should be applied to other situations. I'm not invalidating it, observation does, unless, of course, applying some real science to the dark areas of understanding might shed some light on the dark areas of science.

We have an outstanding amount of observational and experimental evidence validating GR. One anomaly such as "galactic rotational curves" was not going to invalidate such a near certain powerful theory of gravity when other possibilities were possible. DM certainly was a fudge factor, resurrected by Vera Rubin in those early days, but since then, reasonable empirical evidence has been forthcoming, not the least being  the Bullet cluster observation... http://chandra.harvard.edu/press/06_releases/press_082106.html

Quote

P.S. Yes I enjoyed the video very much, but what do you care what other people think?

I always care about what reasonable, logical, sane people without any underlying agenda think: 

Edited by beecee
Link to comment
Share on other sites

On 9/14/2017 at 10:09 AM, swansont said:

No, colored fringes are exactly what you would see in diffraction if you used a wide spectrum source. But people don't generally do this. They use monochromatic light.

spalt1.png

And do we observe this?

No, it's physics.

Yes, diffraction of white light, now what if you removed the boundaries of the slits? There would only be the center blockage, but the diffraction would only occur toward the center because at the extremes, there would be a direct view of the light. Now place your perspective between the rainbow fringes and what do you see?

Also, wouldn't gravitational lensing be considered refraction because the light passes through a gravitational field with variable strength? Only it does not have discrete manipulation of wavelength so it is a diffraction. Having the same object appear in more than one place seems like we do observe exactly that.

Link to comment
Share on other sites

1 hour ago, AbnormallyHonest said:

Yes, diffraction of white light, now what if you removed the boundaries of the slits? There would only be the center blockage, but the diffraction would only occur toward the center because at the extremes, there would be a direct view of the light. Now place your perspective between the rainbow fringes and what do you see?

What does theory predict you will see (I ask, for abut the third time)?

1 hour ago, AbnormallyHonest said:

Also, wouldn't gravitational lensing be considered refraction because the light passes through a gravitational field with variable strength? Only it does not have discrete manipulation of wavelength so it is a diffraction. Having the same object appear in more than one place seems like we do observe exactly that.

Refraction occurs due to a difference in index of refraction (such a coincidence with those names), which is a function of optical properties of a material. So no, gravitational lensing is not refraction.

Link to comment
Share on other sites

and what medium is present where yoy have lensing in regions with average density less than 15 protons per cubic metre?

 

Perhaps you should actually study a dataset taken from a radio telescope that records the different frequencies via a spectrum analyzer.

Its quite easy to distinquish diffraction due to Weins displacement law and that due to gravity.

In the intergalactic medium the refractive index is effectively zero, NOT ENOUGH DENSITY

Edited by Mordred
Link to comment
Share on other sites

Well, since it seems unlikely that "abnormally honest" is going to answer the question I will have a go.
If you have a small source of light  obscured behind an opaque circular object, you get this.
https://en.wikipedia.org/wiki/Arago_spot

The important thing is that it's surrounded by fringes  whose spacing depends on wavelength. 

Now, in the case in point, the  centre dot is obscured by light from the intervening object.

But the rings round it ought to be coloured- and they are not.

 

Link to comment
Share on other sites

On 9/14/2017 at 3:30 PM, John Cuthber said:

You would agree with me if you knew what you were talking about; specifically if you understood the difference between refraction and diffraction.

Both generally cause dispersion.

Only one of then needs more than 1 medium through which the light is transmitted 

No pretty colours means no refraction or diffraction.

 

But gravitational lensing is independent of wavelength.

\theta ={\frac  {4GM}{rc^{2}}}

from 

https://en.wikipedia.org/wiki/Gravitational_lens

Well, the double slit image using white light looks like this

https://en.wikipedia.org/wiki/Double-slit_experiment#/media/File:Double_slit_interference.png

lots of pretty colours.

So, we know that the image attributed to gravitational lensing can't be due to anything like the double slit experiment.

You can stop now.

I do understand, the difference being refraction separates the colors because of the change in velocity through another medium, this causes the oscillations from different wavelengths to change directions which is both a factor of the angle in which it enters the medium and proportional to wavelength. (e.g. some light gets refracted more than others, or it is a discrete influence proportional to wavelength...) This separates the colors producing all those pretty colors.

Diffraction produces all those pretty colors in a much different way, it does this through interference. Diffraction is what happens in G-lensing because there is no change in medium, (although you might argue that the gravitational field or the curvature of spacetime could be considered a change of medium, but as it does not have a discrete influence proportional to wavelength is doesn't produce all those pretty colors) but if the surface is not flat, (which space hardly ever is, especially in gravitational fields) it causes the light to interfere with itself, producing, as you state so eloquently, all those pretty colors... but only at the fringes.

Also, I don't believe that a double slit caused this affect, but a double slit is a reproducible experiment here on Earth, with measurable results that can also make predictions. Could you please reproduce gravitational lensing in a laboratory? Hmmm... well if that's not possible, how about using G-lensing to explain all these validating observations that don't require something we can't see, can't explain, and don't even know if it is real?

I am not the one chasing the Easter Bunny.

Link to comment
Share on other sites

8 minutes ago, AbnormallyHonest said:

Diffraction is what happens in G-lensing

Then you claim that GR is wrong. 

Therefore you need to find an alternative explanation for all the things that are explained by GR.

9 minutes ago, AbnormallyHonest said:

Could you please reproduce gravitational lensing in a laboratory?

Yes. But the effects would be too small to measure.

9 minutes ago, AbnormallyHonest said:

Hmmm... well if that's not possible, how about using G-lensing to explain all these validating observations that don't require something we can't see, can't explain, and don't even know if it is real?

I have no idea what you are asking. Gravitational lensing is caused by matter. I think we can agree that matter is real?

Is this a reference to the fact that we can detect dark matter by gravitational lensing? That is one of the strongest pieces of evidence that dark matter is some form of matter rather than just the fact our theory of gravity is wrong. But it is always possible that some alternative explanation will explain that as well.

Link to comment
Share on other sites

13 hours ago, AbnormallyHonest said:

I do understand, the difference being refraction separates the colors because of the change in velocity through another medium, this causes the oscillations from different wavelengths to change directions which is both a factor of the angle in which it enters the medium and proportional to wavelength. (e.g. some light gets refracted more than others, or it is a discrete influence proportional to wavelength...) This separates the colors producing all those pretty colors.

Diffraction produces all those pretty colors in a much different way, it does this through interference. Diffraction is what happens in G-lensing because there is no change in medium, (although you might argue that the gravitational field or the curvature of spacetime could be considered a change of medium, but as it does not have a discrete influence proportional to wavelength is doesn't produce all those pretty colors) but if the surface is not flat, (which space hardly ever is, especially in gravitational fields) it causes the light to interfere with itself, producing, as you state so eloquently, all those pretty colors... but only at the fringes.

Also, I don't believe that a double slit caused this affect, but a double slit is a reproducible experiment here on Earth, with measurable results that can also make predictions. Could you please reproduce gravitational lensing in a laboratory? Hmmm... well if that's not possible, how about using G-lensing to explain all these validating observations that don't require something we can't see, can't explain, and don't even know if it is real?

I am not the one chasing the Easter Bunny.

Yes, you are. You are chasing an Easter bunny who is also a yeti and a unicorn.

The appearance here is that you know diffraction bends light — but that's it. No understanding of the details. No working through the details. IOW, not actually doing any science. You are doing pattern recognition. Stopping after the first step necessary to do science.

Here's what I wanted you to think through:

Diffraction only works when the features causing diffraction are within a certain size relationship to the wavelength of the light. You can see diffraction of ~1 micron light from a ~1mm slit, but when you scale this up to cm or meter size, you don't. You can extend the range a little with coherent light, but you don't see interference fringes from e.g. light going through a doorway.  

I have a counter-example, too. I mentioned Poisson's spot (aka Arago's spot; John Cuthber provided a link). If we could see diffraction on the scale you want, we should see that effect during an annular eclipse, where a little bit of light makes it past the moon. People notice the effect, if it happened. But we don't see it. The features on the moon are much too large (i.e. the edge is not sharp enough) and the scale of the system is way too big for us to see any interference. And you are proposing that it's happening on an even larger scale. 

 

Link to comment
Share on other sites

21 hours ago, AbnormallyHonest said:

Diffraction is what happens in G-lensing

Diffraction is wavelength dependent.

Gravitational lensing is not.

The observed ring-shaped images of the distant star are not coloured.

So there's only one option; here's a hint- it's not diffraction.

 

I don't need to set up a gravitational lensing experiment in the lab. I can set up a diffraction experiment, show that the outcome doesn't look like the images we see of stars and conclude that- whatever it is that's making those images- it's not diffraction.

 

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.