Miles Davis

MILES DAVIS

Sun, Jan 13, 12:31 Am

to me

Dr John D (Why do you bother with the Dr in a non-professional setting? Just curious)

Sadly I cannot travel to the south-east to be involved. I am truly sad about this as I was an undergraduate in Brighton and have many happy memories.

I will have a look at the design in detail, but having had a quick look I already see some potential problems.

  1. The aim of the experiment. The experiment should be designed to test a hypothesis. Your stated aim does not set out to test a hypothesis. It is therefore only an observation which may help you form a hypothesis that you can test properly later. Making an observation more complex does not make it an experiment.

Presumably, you hope to be able to come to some sort of conclusion about the shape of the Earth from your observation. If that is true why not formulate a hypothesis about the shape of the Earth and then design a good experiment, or even just an observation, that will actually test it. Which brings me to the next point.

  1. The distance involved is not sufficient to come to any reliable conclusion about the shape of the Earth. So many flat Earth tests operate at what I call the margin. They seek to show that a few meters of the expected curve is “absent” when in fact a small amount of refraction can easily account for it. Your proposed experiment seems set-up to do the same thing. I haven’t had time to search the south coast for locations, but I’m sure that I could come up with locations and an experimental design that would give definitive results rather than one that will inevitably lead to endless debate about refraction, beam divergence, reflection on waves, laser passage through wave troughs etc.
  2. I don’t see how the copper pipe will have any significant effect to limit beam divergence.

I have a number of other concerns, but this will do for now.

As I say, I will look at this in more detail and respond again, but given what I have already said I suggest a complete rethink. Have you conducted any preliminary testing of the lasers and torch? Can they be seen over a distance of 20, 25,30,35,40km?  If you know the maximum range it would be easy to design an experiment that would give a conclusive answer. If the maximum range for the “experiment” is 15-20km I fear you are doomed to get results that are inconclusive, but I have seen claims that such lasers have a range of 40km.

Anyway, I thought I should send you my preliminary thoughts as quickly as possible since you seem quite far down the planning process and also seem doomed to ambiguity.

Miles

Sun, Jan 13, 9:20 AM

to Miles

Dear Miles

Thank you for your reply.

My plan is to do a series of experiments which increase in distance.  Obviously, with distance comes added complexities.

The point of this experiment is to keep it simple, clear and understandable, which is why I am using a simple aim and method.

If you would be so good, please could you evaluate the equipment and method and give your opinion on whether it will achieve the aim of the experiment.

A Yes or No statement would be appreciated, that the equipment and method will achieve the aim and if a no, why not and what modification you would recommend, in order for it to achieve the aim.

Regards

Dr John

Miles Davis

Sun, Jan 13, 10:07 AM

John,

Do you have beam divergence information (in mrad) for the lasers? Also the diameter at the aperture?

I am very confused by what you expect the copper pipe to achieve in terms of limiting beam divergence. Surely the effect will be minimal.

Miles

Sun, Jan 13, 9:54 PM

Evening Miles

The laser in the pipe and the cap at the end with the hole in is just to minimise divergence.  Divergence will still happen, we have done a short range test.  The main focus of the experiment is the central intense source of the laser  – it is the observation or non-observation of the source of the laser source that counts, observing the green hazy divergence cannot count, no matter what anyone says, wouldn’t you agree?

Best

John

Miles Davis

Sun, Jan 13, 11:27 PM

“The main focus of the experiment is the central intense source of the laser  – it is the observation or non-observation of the source of the laser source that counts”

How can you know you are observing the source of the laser?

“observing the green hazy divergence cannot count, no matter what anyone says, wouldn’t you agree?    ”    No, I would not agree.  The divergence of the beam tracks back to the source of the laser.

I requested details of the laser divergence in mrad and the diameter of the aperture. Can you provide them?

As I suspected, the copper pipe is simply a prop to make it appear that you are doing something about divergence. It will have almost zero effect.

What subject is your doctorate? I’m finding it hard to believe it was a science subject.

Miles

Sun, Jan 13, 11:58 PM

Evening Miles

We have run some short range trials:

This is sighting the actual “intense source” of the laser with a P1000.  That is how you know you are observing the source of the laser.

Compare to: Here the beam is going off to the observers (P1000) diagonal top right.

In this photograph you can follow the beam down to where you can image the source may be, but it is not possible to confirm if the source (laser) is where it is said to be and whether that is the actual source.  The top picture on the other hand clearly shows the observer is sighting the source directly.

If the source is being directly sighted then, in the parameters of this experiment, the divergence of the beam is irrelevant, thus, the copper pipe does not have a significant effect, but that is not particularly relevent, in the parameters of this experiment, as long as the intense laser source can be sighted.

Would you agree that a P1000 recording the intense laser source (as shown in the first picture above), under the parameters in the Aim of the experiment (below), would give a positive.

Aim:  Can a light source horizontal (or close to horizontal) to the ground and no more than 1 metre above tide level, be observed 15.3 km away over the sea in the evening, by a camera horizontal (or close to horizontal) to the ground and no more than 1 metre above tide level?

Thanks for your time

Best

John

Miles Davis

Jan 14, 2019, 7:04 AM

The P1000 would record something similar to the first photo from anywhere within the diverged laser beam.   The second shot is taken from well away from the diverged laser beam.

You are repeatedly demonstrating that you do not have any of the necessary knowledge to even attempt “experiments” of this sort.

Miles

Jan 14, 2019, 11:32 PM

to Miles

Evening Miles

Please could you confirm your statement:

“The main focus of the experiment is the central intense source of the laser  – it is the observation or non-observation of the source of the laser source that counts”

How can you know you are observing the source of the laser?

“observing the green hazy divergence cannot count, no matter what anyone says, wouldn’t you agree?    ”    No, I would not agree.  The divergence of the beam tracks back to the source of the laser.

I do not understand why you said that that you would not agree that the main focus is the central source of the laser.  You said “No, I would not agree.”  “the divergence of the beam tracks back to the laser.”

So, the aim of the experiment is to determine:

Can a light source horizontal (or close to horizontal) to the ground and no more than 1 metre above tide level, be observed 15.3 km away over the sea in the evening, by a camera horizontal (or close to horizontal) to the ground and no more than 1 metre above tide level?

Your statement is implying that sighting the intense laser source is not necessary to give a positive that the laser has been sighted according to the above parameters, just the sighting of a diverging beam (as “the divergence of the beam tracks back to the laser”).  I myself think just seeing the diverging beam is not enough – the source of the laser must be sighted, so I take it you are satisfied that the experimental method and equipment will be able to test the simple aim of the experiment?

Best

John

Miles Davis

Wed, Jan 16, 1:05 PM

John,

You seem to have absolutely no idea what is meant by divergence. Perhaps you are explaining yourself poorly.

My point is this.    At the location of the camera, the laser has become a large circle due to the divergence of the beam. (I don’t know how large that circle will be because you won’t tell me the divergence properties of the laser you are using.)  If the camera is anywhere within that circle of divergence then the camera will see the source of the laser.

 

You seemed to be saying that the divergence circle of the laser was not coming directly from the source of the laser.

It is also true that light that is refracted on its path from the laser to the camera will appear to come directly from the laser.

It will also be impossible to distinguish between light that comes directly from the laser to the camera and light that is reflected from the surface of the water/waves.

Perhaps the attached diagram will illustrate the issues you will be facing.  It is only a rough diagram, it is not meant to be to scale and obviously, the divergence is somewhat exaggerated, but without knowing the divergence properties of your lasers I cannot do a scale diagram.

Miles

Jan 16, 2019, 11:56 PM

Evening Miles

Thanks for the email.

I understand about divergence.  It is the aim of the experiment that is important to me and the role divergence plays.

 

If the camera is in the circle of divergence and looking at the correct angle towards the laser, the intense laser source will be observed.

As shown above.  If the laser and camera are both 1 metre above tide level (15.3 km away) and horizonal to the ground, the camera should not be able to observe the intense laser source no matter how much divergence is occuring.  The light will diverge as it leaves the laser.  The lower part of the diverging beam would strike the water curvature of the water and be reflected (diffuse) upwards toward the sky.

The top section of the diverging laser light will travel over the curvature of the water and keep travelling and will go over the top of the camera and will not be observed – that is the most important part for this experiment.

If the intense laser source can be seen.  Then this must be due to one of two factors:

  1. The course of the beam of light between Brighton and Worthing is not as expected.

or

  1. The profile of the sea between Brighton and Worthing is not as expected.

The only way it could be number 1, is if the diverging laser beam was refracted in a downwards direction.

But, light is not refracted in a downwards direction over the sea in the evening/night under normal, everyday, non-specialised conditions between 0 – 2 metres above tide level, it is refracted in an upwards direction.  Due to the specific heat capacity of the water etc. and the layer of air directly above the water being warmed and then expanding and rising (and having a higher relative humidity than the air above it), makes the air above this bottom layer of air more dense, which casuses light at low elevations to be refracted upwards.  I have explained this fully in my videos and land and sea breezes are based on this – this is common knowledge.

Temperature measurements and relative humidity readings from 0 – 2 metres above tide level can be taken and they will indicate the air density profile between the measured elevations, which will indicate if and in what direction refraction will occur.

Check the pictures below.

 

 

I have not taken a picture that shows light refracting in a downward direction (over the sea in the evening/night under normal, everyday, non-specialised conditions).

There isn’t a picture on the internet that I can find that shows light refracting in a downward direction (over the sea in the evening/night under normal, everyday, non-specialised conditions).  If you could please provide me one, if you have one, I would appreciate that.

If the diverging beam of light is either not refracting or refarcting in an upward direction and can be seen, this leads to the conclusion that the profile of the sea is not expected.

If you believe that light refracts in a downward direction (over the sea in the evening/night under normal, everyday, non-specialised conditions), between 0 – 2 metres above tide level,  please send me the empirical evidence that supports this and we can continue the refraction discussion.

So, if the intense laser source is observed, the observations, temperature and relative humidity readings should lead us through a series of logical deductions leading to either:

  1. The course of the beam of light between Brighton and Worthing is not as expected.

or

  1. The profile of the sea between Brighton and Worthing is not as expected.

It’s that simple and to the point….   the scientific principles behind this can’t be proved wrong.

If the bottom of the diverging laser beam was “cut off” by the curvature, what would the picture look like?  Your thoughts?

I look forward to discussing this with you further

Best

John

 

Status:  Still waiting a reply………